WO2015182157A1 - Hybrid propulsion system for mobile object, and method for controlling said system - Google Patents

Abstract

A hybrid propulsion system (10) for a mobile object is provided with an motor generator (19), a first power converter (25a), a second power converter (25b), and a controller (14), the controller including a first power command value output unit (140), a second power command value output unit (141), a mode selection unit (144), and a droop control unit (145). On the basis of a power command value, the droop control unit performs a control such that the frequency of a power system (18) and the generated power or electrical power from the motor generator is one point on a droop characteristic curve showing the relationship between a frequency target value of the power system, and a target value for the generated power or electrical power from the motor generator. The controller is configured so as to control the second power converter so that the voltage of a direct-current intermediate unit is fixed.

Description

Hybrid propulsion system for moving body and control method thereof

The present invention relates to a hybrid propulsion system for a mobile body including a motor generator that performs an electric operation and a power generation operation and a bidirectional power conversion device, and a control method thereof.

As a conventional marine hybrid propulsion system including a motor generator that performs an electric operation and a power generation operation, for example, a configuration of a first conventional technique shown in Patent Document 1 is known. As a method for controlling the motor generator, a second prior art method shown in Non-Patent Document 1 is disclosed. In the method of Non-Patent Document 1, control with a droop characteristic equivalent to a generator (hereinafter referred to as “droop control”) is performed on the power conversion device, thereby performing interconnection operation and independent operation. In either case, the motor generator can be controlled.

German Patent No. 10-2005-059-760

G. Marina & E. Gatti, “Large Power PWM IGBT Converter for Shaft Alternator Systems”, 35th Annual IEEE Power Electronics Specialists Conference, 2004

In the prior arts shown in Patent Document 1 and Non-Patent Document 1, there is still room for improvement regarding seamless switching of the control of the bidirectional power converter. Such a problem is not limited to the marine hybrid propulsion system disclosed in Patent Document 1, but is common to a hybrid propulsion system for a moving body such as an automobile or a railway vehicle.

The present invention has been made to solve such a problem, and an object thereof is to provide a mobile hybrid propulsion system capable of seamlessly switching the control of the bidirectional power converter.

A hybrid propulsion system for a moving body according to an aspect of the present invention includes a motor generator connected to a drive shaft that drives a propulsion device that propels the moving body by a rotational force so that power can be transmitted, and an AC terminal connected to an electric power system. A first power converter having a DC terminal connected to the DC intermediate part, a second power converter having a DC terminal connected to the DC intermediate part and an AC terminal connected to the motor generator, A command value can be set, a first power command value output unit that outputs a power command value based on a deviation of the rotation speed of the motor generator from the set rotation speed command value, and a power command value can be set Yes, selecting a second power command value output unit that outputs a set power command value, a power command value from the first power command value output unit, and a power command value from the second power command value output unit Mode selection unit for outputting A droop control unit that droop-controls the first power converter based on a power command value output from the de-selection unit, and the second power converter is controlled so that the voltage of the DC intermediate unit is constant. A configured second power converter control unit.

According to this configuration, the power command value based on the rotation speed command value from the first power command value output unit and the power command value from the second power command value output unit are selected, and the selected power command value is selected. Based on this, the first power converter is droop controlled. Thereby, droop control can be performed in both the rotation speed control mode and the power control mode. Therefore, even when the rotation speed control mode and the power control mode are switched, the control can be switched seamlessly.

Also, the power command value based on the rotation speed command value from the first power command value output unit and the power command value from the second power command value output unit are selected. Thereby, the rotation speed control mode and the power control mode can be appropriately used according to the state of the system.

In the hybrid propulsion system for a mobile object, the droop control unit generates power of the motor generator that is given to or received from the power system by the frequency of the power system and the first power converter based on the power command value. The power or the electric power (hereinafter referred to as “system transmission / reception power”) is controlled so as to be one point on the droop characteristic line indicating the relationship between the frequency target value of the power system and the target value of the system transmission / reception power. May be.

In the mobile hybrid propulsion system, the droop characteristic line is set to a power command value for a standard frequency of the power system, and the motor generator is smaller than a power command value for a frequency higher than the standard frequency. The generated power or the electric power larger than the electric power command value is set, and the electric power lower than the standard frequency is set to the electric power smaller than the electric power generation value or the electric power command value larger than the electric power command value. Also good. According to this configuration, the droop characteristic line indicating the relationship between the frequency target value of the power system and the target value of the power exchanged to the system of the first power converter is preferably set in order to link with the main generator. Can do.

In the mobile hybrid propulsion system, the droop control unit may be configured to control the frequency of the power system so as to be a frequency obtained from the actual transmission / reception power of the system and the droop characteristic line. . According to this configuration, the frequency of the first power converter can be controlled by droop control.

In the mobile hybrid propulsion system, the droop control unit is configured to control the pair power transmission / reception power to be the pair power transmission / reception power obtained from the actual frequency of the power system and the droop characteristic line. It may be. According to this configuration, the first power converter can be power controlled by droop control.

In the hybrid propulsion system for a moving body, the power command value output from the mode selection unit is obtained by calculating a power command value from the first power command value output unit and a power command value from the second power command value output unit. When switching between them, you may comprise so that the said electric power command value input into the said droop control part may change continuously. According to this configuration, when the rotation speed control mode and the power control mode are switched, the power command value does not change abruptly, thereby preventing a sudden change in the thrust of the ship or the supplied power.

The mobile hybrid propulsion system may further include a rate limiter that limits the change of the power command value output from the mode selection unit to the droop control unit. According to this configuration, since the rapid change in the power command value is further suppressed by the rate limiter, it is possible to prevent a sudden change in the thrust of the ship or the supplied power.

The hybrid propulsion system for a moving body further includes a prime mover connected to the drive shaft that drives the propulsion unit so that power can be transmitted, and when the prime mover is operated and the number of revolutions is controlled, the mode selection unit includes: You may be comprised so that the electric power command value from a 2nd electric power command value output part may be selected and output. According to this configuration, when the number of revolutions of the prime mover is controlled, the motor generator is controlled in electric power, so that overloading of the prime mover and the motor generator is prevented.

In the mobile hybrid propulsion system, when no other device that supplies power to the power system is connected, the mode selection unit selects and outputs the power command value from the second power command value output unit. It may be configured to. According to this configuration, power control of the motor generator can prevent a power failure or an overload of the motor generator.

In the hybrid propulsion system for a mobile body, the mobile body has a power management system that outputs a power generation request to each power generation facility so that the power supply satisfies power demand, and the mode selection unit is configured to output the power management system from the power management system. When a power generation request is received, the power command value from the second power command value output unit may be selected and output. According to this configuration, power control of the motor generator can prevent a power failure or an overload of the motor generator.

When the hybrid propulsion system for a mobile body detects a load that acts on the drive shaft that drives the propulsion unit or a periodic variation of the rotation speed of the propulsion unit, and the amplitude of the variation is equal to or greater than a predetermined threshold value The mode selection unit may be configured to select and output a power command value from the first power command value output unit. According to this configuration, when the load on the drive shaft or the rotational speed of the propulsion device has a large amplitude of periodic fluctuation, the rotational speed of the propulsion device is prevented from exceeding by controlling the rotational speed of the motor generator. be able to.

The hybrid propulsion system for a moving body detects a rotational speed of the drive shaft that drives the propulsion device, and when the rotational speed is equal to or greater than a predetermined threshold, the mode selection unit is configured to output the first power command value output unit. It may be configured to select and output a power command value from. According to this configuration, when the rotational speed of the drive shaft is high, the rotational speed of the propulsion device can be prevented from exceeding by controlling the rotational speed of the motor generator.

The hybrid propulsion system for a moving body further includes a lever, the first power command value output unit sets the rotation speed command value based on an operation amount of the lever, and the second power command value output unit includes: The power command value may be set based on an operation amount of the lever. According to this configuration, since the rotation speed command value and the power command value can be input with one lever, the operability is excellent.

In the hybrid propulsion system for a moving body, the power command value output from the mode selection unit is obtained by calculating a power command value from the first power command value output unit and a power command value from the second power command value output unit. When switching between, the setting of the rotation speed command value or the power command value by operating the lever is invalidated, and the actual rotation speed of the motor generator immediately before the switching is set to a temporary rotation speed command value. Then, until the rotation speed command value from the first power command value output unit corresponding to the operation amount of the lever matches the temporary rotation speed command value, or the lever gives a discrete operation amount. In this case, the invalidation is canceled at the time when the lever is operated up to the position corresponding to the value corresponding to the value closest to the temporary rotational speed command value, or at the time immediately before the switching. Until the power command value from the second power command value output unit corresponding to the amount of operation of the lever matches the temporary power command value. Or when the lever gives a discrete operation amount, the invalidation is canceled when the lever is operated to a position where the operation amount corresponds to a value closest to the temporary power command value. It may be. According to this configuration, it is possible to prevent a command value not intended by the operator from being input by disabling the lever when switching the control mode.

In the hybrid propulsion system for a moving body, the first power command value output unit includes an integration element, and the power command value output from the mode selection unit is determined from the power command value from the second power command value output unit. When switching to the power command value from the 1 power command value output unit, the integration element so that the power command value from the first power command value output unit coincides with the actual power transfer to and from the grid immediately before the switching. It may be configured to set the value of. According to this configuration, it is possible to prevent an abrupt change in the actual system power transmission / reception by appropriately setting the value of the integral element.

The hybrid propulsion system for a mobile body further includes a display unit, and displays the invalidation on the display unit while the setting of the rotation speed command value or the power command value by the operation of the lever is invalidated. It may be configured. According to this configuration, it is possible to notify the operator of the invalidation by displaying the invalidation of the lever.

The moving body hybrid propulsion system may further include a lever, and the moving body may be a ship.

In the hybrid propulsion system for a moving body, the lever may further serve as a rotational speed command or a fuel supply amount command for a prime mover connected to the drive shaft so that power can be transmitted. According to this configuration, since the engine speed command or the fuel supply amount command can be further input by the lever, the operability is excellent.

In the mobile hybrid propulsion system, the propulsion device may be a variable pitch propeller, and the lever may further serve as a blade angle command for the variable pitch propeller. According to this configuration, since the lever angle command of the variable pitch propeller can be further input by the lever, the operability is excellent.

In the hybrid propulsion system for a moving body, the propulsion device is a variable pitch propeller, and the lever receives a rotational speed command of a prime mover connected to the drive shaft so that power can be transmitted and a blade angle command of the variable pitch propeller. It may further have a function of simultaneously instructing along a predetermined combination curve. According to this configuration, since the rotational speed command of the prime mover and the blade angle command of the variable pitch propeller can be simultaneously input by the lever along the combination curve, the operability and fuel efficiency are excellent.

A control method of a hybrid propulsion system for a moving body according to an aspect of the present invention includes a motor generator connected to a drive shaft that drives a propulsion unit that propels the moving body by a rotational force so that power can be transmitted, A first power converter connected to the grid and having a DC terminal connected to the DC intermediate part; a second power converter having a DC terminal connected to the DC intermediate part and an AC terminal connected to the motor generator; , A rotational speed command value is set, and a power command value is output based on a deviation of the rotational speed of the motor generator with respect to the set rotational speed command value A first power command value output step, a second power command value output step for setting the power command value and outputting the set power command value, a power command value for the first power command value output step, and the second Power finger A mode selection step of selecting and outputting a power command value of a value output step, a droop control step of drooping controlling the first power converter based on the power command value output by the mode selection step, and the direct current And a second power converter control step for controlling the second power converter so that the voltage at the intermediate portion becomes constant.

In the control method of the hybrid propulsion system for a mobile object, in the droop control step, the motor power generation that is given or received by the frequency of the power system and the first power converter to or from the power system based on the power command value The generated power or the electric power of the machine (hereinafter referred to as “system transmission / reception power”) is controlled so as to be a point on the droop characteristic line indicating the relationship between the frequency target value of the power system and the target value of the system transmission / reception power. May be.

The present invention has the above-described configuration, and provides an effect that it is possible to provide a hybrid propulsion system for a moving body that can seamlessly switch the operation of the bidirectional power converter.

The above object, other objects, features, and advantages of the present invention will become apparent from the following detailed description of preferred embodiments with reference to the accompanying drawings.

1 is a block diagram schematically showing a hybrid propulsion system for a moving body according to Embodiment 1 of the present invention. FIG. 2A is a droop characteristic line that is set when controlling a motor generator that performs a power generation operation. FIG. 2B is a droop characteristic line that is set when controlling a motor generator that operates electrically. FIG. 3A is a droop characteristic line during frequency control. FIG. 3B is a droop characteristic line during power control. It is a block diagram which shows the structural example of the controller of the hybrid propulsion system of a moving body. It is a block diagram which shows roughly the controller of the hybrid propulsion system of the mobile body which concerns on Embodiment 2 of this invention. It is a block diagram which shows roughly the hybrid propulsion system of the moving body which concerns on Embodiment 3 of this invention. It is a figure which shows the operation mode of the hybrid propulsion system of FIG. FIG. 7 is a block diagram schematically showing the controller of FIG. 6. It is a block diagram which shows roughly the hybrid propulsion system of the moving body which concerns on Embodiment 5 of this invention. It is a block diagram which shows roughly the controller of the hybrid propulsion system of the moving body which concerns on Embodiment 6 of this invention. It is a table | surface which shows each control method of the 1st power converter and the 2nd power converter in each operation mode of 1st and 2nd prior art, and this invention.

(Knowledge that became the basis of the present invention)
The inventors of the present invention have studied the seamless switching of the control of the bidirectional power conversion apparatus with respect to the mobile hybrid propulsion system. For example, in a system including a motor and a power system generator in addition to a motor generator, the bidirectional power conversion device includes a self-sustained operation in which the motor generator generates power alone, and the motor generator and the power system generator. It is necessary to perform grid-connected operation in which both sides generate electricity. On the other hand, as shown in FIG. 11, there are four operation modes as operation modes of the prime mover, the generator, and the motor generator. Examples of the operation mode include an electric propulsion mode, a propulsion boost mode, a parallel mode, and a shaft start mode.

For example, in the electric propulsion mode, the prime mover stops and the motor generator operates electrically. In this case, since there is no other power source for controlling the rotation speed of the propulsion device, it is necessary to control the rotation speed of the motor generator. This motor generator is controlled by a bidirectional power converter. The bidirectional power conversion device is provided between the power system and the motor generator, and includes a system side power converter, a motor generator side power converter, and a direct current intermediate unit that connects the two.

In the electric propulsion mode of the first prior art, the motor generator is subjected to motor drive control (for example, vector control) by the motor generator side power converter, thereby controlling the rotation speed of the motor generator and the system side power converter. The DC intermediate voltage constant control is performed. On the other hand, in operation modes other than the electric propulsion mode (propulsion boost mode, parallel mode, and axial mode), the system side power converter performs droop control on the power system, thereby maintaining power while maintaining the system frequency. While adjusting supply and demand, DC intermediate voltage constant control is performed by the motor-generator-side power converter. For this reason, when making a transition from the electric propulsion mode to another operation mode, the control method of the bidirectional power converter must be switched.

For example, when a heavy object is towed while operating in the electric propulsion mode, the electric propulsion mode is shifted to the propulsion boost mode with a large supplyable thrust. At this time, the system side power converter switches the control method from DC intermediate voltage control to droop control, and the motor generator side power converter switches the control method from motor drive control to DC intermediate voltage constant control. Here, the fact that both the system-side power converter and the motor-generator-side power converter perform constant DC intermediate voltage constant control simultaneously causes a destabilization of the control. For this reason, there has been a problem that the hybrid propulsion system has to be stopped once despite the situation where the thrust must be maintained.

In the electric propulsion mode of the second prior art, the motor drive control is performed by the motor drive control by the motor generator side power converter, and the DC intermediate voltage constant control is performed by the system side power converter. ing. In the propulsion boost mode, the motor drive is controlled by the motor generator side power converter to control the power of the motor generator, and the DC intermediate voltage constant control is performed by the system side power converter. In contrast, in the parallel mode and the axial mode in which the motor generator generates power, the system side power converter performs droop control on the power system, and the motor generator side power converter performs DC intermediate voltage constant control. ing. For this reason, when switching between electric operation and power generation operation, the control method of the bidirectional power converter must be switched.

On the other hand, in a marine hybrid propulsion system, for example, load fluctuations such as waves are absorbed, thereby minimizing the fuel consumption of the generator. For this reason, the electric operation and the power generation operation of the motor generator are frequently switched every several seconds. However, the hybrid propulsion system has to be stopped once when the operation is switched, and it takes time to change the control method, so that there is a problem that fuel consumption cannot be improved.

From the above analysis, the present inventors have paid attention to the fact that the above-mentioned problems can be solved by making both the droop control for the system-side power converter, the rotation speed control of the motor generator, and the power control compatible.

Then, the inventors perform droop control on the power converter on the system side, and perform droop control by providing selectable motor speed control and power control above the droop control. It was found that the rotational speed control and power control of the motor generator can be performed while being always effective. According to this knowledge, it is possible to seamlessly switch between the autonomous operation and the grid interconnection operation of the bidirectional power converter, and to perform the rotational speed control and power control of the motor generator, and to seamlessly perform both. You can switch to That is, the hybrid propulsion system does not stop at any transition between the electric propulsion mode and the propulsion boost mode, the propulsion boost mode and the parallel mode, and the parallel mode and the axial mode.

The present invention has been made based on this finding.

Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. In the following description, the same or corresponding elements are denoted by the same reference symbols throughout all the drawings, and redundant description thereof is omitted.

(Embodiment 1)
FIG. 1 is a block diagram schematically showing a mobile hybrid propulsion system 10 according to the first embodiment. As shown in FIG. 1, the mobile body includes a hybrid propulsion system 10 and a propulsion device 11. The hybrid propulsion system 10 includes a motor generator 19, a power converter 25, and a controller 14. One or more motor generators 19 are provided on the moving body. The moving body is an object that moves due to the thrust generated by the propulsion device 11, and examples thereof include ships, automobiles, and railway vehicles.

The propulsion device 11 is a device that propels a moving body, and examples thereof include a propeller and a drive wheel (tire, caterpillar, etc.). The propulsion unit 11 has a drive shaft connected to the motor generator 19 of the hybrid propulsion system 10 and converts the power input from the motor generator 19 into thrust of the moving body.

The motor generator 19 has an electric function for converting AC power into power and a power generation function for converting power into AC power. The motor generator 19 is connected to a drive shaft that drives the propulsion device 11 by rotational force so as to be able to transmit power. For example, the motor generator 19 is connected to the drive shaft of the propulsion device 11 by a power transmission mechanism such as a speed reducer and a detachable clutch. It is connected. In addition, the electric terminal of the motor generator 19 is connected to the power system 18 via the bidirectional power converter 25 and also connected to the power load via the bus. When the motor generator 19 functions (electric operation) as a motor, the motor generator 19 converts electric power input from the power system 18 via the power converter 25 into rotational power and transmits the power to the propulsion device 11. On the other hand, when the motor generator 19 functions (power generation operation) as a generator, the motor generator 19 converts the rotational power input from the propulsion device 11 into electric power, and outputs the electric power to the bus via the power converter 25.

The electric power system 18 is composed of other power sources such as a bus (not shown), a power load (not shown) connected to the bus, and a generator (not shown).

The bidirectional power converter 25 converts alternating current power into direct current power, converts the direct current power obtained by the conversion into alternating current power, and converts the alternating current frequency and voltage between the power system 18 and the motor generator 19 to each other. It is a device to convert to. The power converter 25 has one terminal connected to the power system 18 and the other terminal connected to the motor generator 19. Specifically, the power conversion device 25 includes a first power converter 25a, a second power converter 25b, and a DC link capacitor 25c. The 1st power converter 25a and the 2nd power converter 25b are connected by the DC link (direct current intermediate part) comprised by a pair of wiring. The DC link capacitor 25c is connected to the DC link, and smoothes fluctuations in the DC link voltage (DC intermediate voltage).

1st power converter 25a is a system side power converter, and is constituted by a bidirectional inverter, for example. The AC terminal of the first power converter 25a is connected to the power system 18, and the DC terminal is connected to the DC link. The first power converter 25 a converts the DC power input from the DC link into AC power and outputs the AC power to the power system 18. The AC power input from the power system 18 is converted into DC power and output to the DC link.

The second power converter 25b is a motor-generator-side power converter, and is composed of, for example, a bidirectional inverter. The direct current end of the second power converter 25 b is connected to the DC link, and the alternating current end is connected to the motor generator 19. The second power converter 25b converts AC power input from the motor generator 19 into DC power and outputs the DC power to the DC link. Also, the DC power input from the DC link is converted into AC power and output to the motor generator 19.

The controller 14 controls the motor generator 19 by performing the droop control on the first power converter 25a and controlling the second power converter 25b so that the DC intermediate voltage becomes constant. The “droop control” is a control in which the first power converter 25a has characteristics corresponding to the generator by building a governor model for controlling the generator inside the controller 14. As a result of the first power converter 25a having characteristics corresponding to a generator, it is possible to seamlessly switch between independent operation and grid-connected operation.

“Droop control” is a well-known technique, so a detailed explanation is omitted. For details of the “droop control”, refer to Non-Patent Document 1 and the like. In the “droop control”, the frequency of the power system 18 and the power (active power) transmitted and received by the first power converter 25a to the power system 18 are detected by respective sensors (not shown). The signal is input to the controller 14 (more precisely, a droop control unit 145 (see FIG. 4) described later) and used for these controls in the droop control.

In the present embodiment, the rotational speed control and power control of the motor generator 19 are provided so as to be selectable above the “droop control”. Specifically, in the present embodiment, in the droop control, the droop characteristic line is set based on the standard frequency of the power system 18 and the power command value Pc. And the frequency of the electric power grid | system 18 or the electric power of the 1st power converter 25a is controlled so that it may become the target value on a droop characteristic line. This droop characteristic line shows the relationship between the frequency target value of the electric power system 18 and the target value of “electric power supplied / received” of the first power converter 25a. In the present embodiment, the power that the first power converter 25a gives (outputs) to the power system 18 corresponds to the generated power of the motor generator 19, and the first power converter 25a receives from the power system 18 ( The input power corresponds to the electric power of the motor generator 19. Therefore, for the sake of convenience, the generated power of the motor generator 19 that the first power converter 25a gives to the power system 18 or the motor power of the motor generator 19 that the first power converter 25a receives to the power system 18 is used. This is called “vs. Note that “power exchanged with the grid” means active power out of the power exchanged with the power grid 18 by the first power converter 25a.

Next, a method for setting the droop characteristic line will be described with reference to FIGS. 2A and 2B. 2A and 2B are graphs showing droop characteristic lines. FIG. 2A is a droop characteristic line that is set when the motor generator 19 that performs a power generation operation is controlled. FIG. 2B is a droop characteristic line set when controlling the motor generator 19 that is electrically operated. The vertical axis of each graph shows the frequency of the power system 18, and the horizontal axis shows the power exchanged with the system. As shown in FIGS. 2A and 2B, in the droop characteristic line, the generated power increases and the electric power decreases as the frequency of the power system 18 decreases.

The droop characteristic line is determined by the standard frequency Fs of the power system 18, the power command value Pc for the motor generator 19, and the slope. The standard frequency Fs of the power system 18 is predetermined for each power system 18, and for example, the standard frequency of a power source in a ship: 60 Hz or the standard frequency of a power source in Japan: 60 Hz or 50 Hz is used. The power command value Pc is set based on operation information input by an operator or the like, as will be described later. The slope of the droop characteristic line is a predetermined value. For this reason, the droop characteristic line is set so as to pass through a point determined by the standard frequency Fs and the power command value Pc. Thereby, a droop characteristic line can be changed according to electric power command value Pc. Here, the standard frequency Fs is set to the frequency of the electric power system 18, but the standard frequency Fs is set as appropriate.

Next, the droop control method will be described with reference to FIGS. 3A and 3B. 3A and 3B are graphs showing droop characteristic lines. As described above, the droop characteristic line is set based on the standard frequency Fs of the power system 18 and the power command value Pc. FIG. 3A is a droop characteristic line during frequency control. FIG. 3B is a droop characteristic line during power control. The vertical axis of each graph shows the frequency of the power system 18, and the horizontal axis shows the power exchanged with the system.

The frequency (actual value) f of the actual power system 18 and the actual power transmission / reception power (actual value) P are indicated by X in each graph. In the frequency control of FIG. 3A, the actual value f of the frequency of the power system 18 indicated by X is smaller than the frequency target value f ^{* obtained} from the actual value P of the power exchanged with the system indicated by X and the droop characteristic line. For this reason, the first power converter 25a is controlled so that the actual value f of the frequency of the power system 18 becomes the frequency target value f ^* . Further, in the power control of FIG. 3B, the actual value P of the power exchanged with respect to the grid indicated by X is smaller than the power target value P ^* obtained from the actual value f of the frequency of the power grid 18 indicated by X and the droop characteristic line. . For this reason, the 1st power converter 25a is controlled so that the actual value P of power transmission / reception power becomes the power target value P ^* .

Next, a specific configuration of the controller 14 will be described with reference to FIG. FIG. 4 is a block diagram illustrating a configuration example of the controller 14 of the mobile hybrid propulsion system 10.

The controller 14 includes an arithmetic device and includes a first power converter control unit and a second power converter control unit 130. The first power converter control unit includes a first power command value output unit 140, a second power command value output unit 141, a mode selection unit 144, and a droop control unit 145. The first power command value output unit 140 includes a second power command value output unit 141 and a PID control unit 143. Each unit of the controller 14 is a function realized by executing a built-in program by the arithmetic device.

In the first power conversion control unit, the first power command value output unit 140 can set the rotation speed command value, and the power command based on the deviation of the rotation speed of the motor generator 19 with respect to the set rotation speed command value. Output the value. The second power command value output unit 141 can set a power command value and outputs the set power command value. The mode selection unit 144 selects and outputs the power command value from the first power command value output unit 140 and the power command value from the second power command value output unit 141 based on the mode command. The droop control unit 145 performs the droop control on the first power converter 25a based on the power command value output from the mode selection unit 144. Here, the droop control unit 145 performs control so that the frequency of the power system 18 and the power supplied to and received from the system become one point on the droop characteristic line based on the power command value. In addition, the second power converter control unit 130 controls the second power converter 25b so that the voltage of the DC intermediate part is constant.

Next, the operation (control method) of the mobile hybrid propulsion system 10 will be described with reference to FIG. Here, the motor generator 19 has a rotation speed control mode and a power control mode. This rotational speed control mode or power control mode is switched according to the operation mode of the motor generator 19 shown in FIG. FIG. 1 shows a configuration in which only the motor generator 19 is connected to the propulsion device 11. In this configuration, the mobile hybrid propulsion system 10 has only an electric propulsion mode.

On the other hand, the motor generator 19 and a prime mover (not shown) may be connected to the propulsion device 11 via a power transmission mechanism (not shown). In this configuration, the mobile hybrid propulsion system 10 has an electric propulsion mode, a propulsion bias mode, a parallel mode, and an axial mode. For example, in the electric propulsion mode, the motor generator 19 is controlled in rotational speed. In the propulsion boost mode, the parallel mode, and the axial mode, the prime mover is generally controlled in rotational speed, and the motor generator 19 is generally controlled in electric power. However, it is theoretically possible to use the rotational speed control mode when the motor generator 19 performs a power generation operation (parallel mode and axial mode). Hereinafter, the operation mode in which the motor generator 19 is controlled in rotation speed is referred to as “rotation speed control mode”, and the operation mode in which the motor generator 19 is subjected to power control is referred to as “power control mode”.

When controlling the rotational speed of the motor generator 19, a mode command indicating that the rotational speed control mode is set is received from the input unit 29 (see FIG. 8), and the mode selection unit 144 selects the rotational speed control mode. Thus, when the operator operates a lever or the like to adjust the thrust, the operation information is output to the rotation speed command value generation unit 142 of the first power command value output unit 140. The rotation speed command value generation unit 142 generates a rotation speed command value nc corresponding to the input operation information, based on a lookup table indicating the relationship between the built-in operation information and the rotation command value. In the PID control unit 143, a deviation Δn between the input rotational speed command value nc and the actual rotational speed (actual value) n of the motor generator 19 is obtained, and the rotational speed deviation is proportionally processed, integrated, and differentiated. By doing so, the electric power command value Pc is generated.

Here, since it is the rotational speed control of the motor generator 19, the mode selection unit 144 outputs the power command value Pc from the first power command value output unit 140 to the droop control unit 145. The droop control unit 145 sets a droop characteristic line as shown in FIG. 2A or 2B based on the power command value Pc. By this droop characteristic line, the frequency target value f ^* of the electric power system 18 or the target value P ^{* of the} power supplied / received to the system corresponding to the operation information is determined.

When the droop control unit 145 controls the frequency of the first power converter 25a, as shown in FIG. 3A, the frequency target value f ^* is obtained from the actual value P of the power supplied to the system and the droop characteristic line. Then, the deviation Δf of the actual frequency value f with respect to the frequency target value f ^* is output to the first power converter 25a. Accordingly, the first power converter 25a is droop-controlled so that the actual frequency value f becomes the frequency target value f ^* .

When the droop control unit 145 controls the power of the first power converter 25a, the power target value P ^* is obtained from the actual frequency f of the power system 18 and the droop characteristic line as shown in FIG. 3B. . And deviation (DELTA) P of the actual value P of the transmission / reception power with respect to electric power target value P ^* is output to the 1st power converter 25a. Thereby, the first power converter 25a is droop-controlled so that the actual value P of the power exchanged with the system becomes the power target value P ^* .

Thus, when the frequency of the power system 18 or the power exchanged with the system is controlled, the DC intermediate voltage fluctuates accordingly. In response to this, the second power converter control unit 130 controls the second power converter 25b so that the DC intermediate voltage is constant. Then, according to this control, the motor generator 19 performs a power generation operation or an electric operation. The rotational speed of the motor generator 19 in the power generation operation of the motor generator 19 is determined by the difference between the power supplied from the prime mover and the power given to the power system 18 from the first power converter 25a. The rotational speed of the motor generator 19 in the motor operation of the motor generator 19 is determined by the sum of the power transmitted to the propulsion device 11, that is, the power supplied from the prime mover and the power received by the first power converter 25a from the power system. Determined. The rotation speed of the motor generator 19 determined in this way is input to the first power command value output unit 140. By the above control, the droop control for the first power converter 25a is performed, and the rotation speed of the motor generator 19 is feedback-controlled.

On the other hand, when power control is performed on the motor generator 19, the mode selection unit 144 selects a power control mode upon receiving a mode command indicating that it is in the power control mode from the input unit 29 (see FIG. 9). Thus, when the operator operates a lever or the like to adjust the thrust, the operation information is output to the second power command value output unit 141. The second power command value output unit 141 generates a power command value Pc corresponding to the input operation information based on a lookup table indicating the relationship between the built-in operation information and the power command value.

Here, since it is power control of the motor generator 19, the mode selection unit 144 outputs the power command value Pc from the second power command value output unit 141 to the droop control unit 145. The droop control unit 145 is controlled in the same manner as in the above-described rotation speed control mode, and accordingly, the DC intermediate voltage varies. In response to this, the second power converter control unit 130 controls the second power converter 25b so that the DC intermediate voltage is constant. Then, according to this control, the motor generator 19 performs a power generation operation or an electric operation. The power generated by the motor generator 19 in the power generation operation of the motor generator 19 is determined by the power given to the power system 18 from the first power converter 25a, and the power necessary for power generation is supplied from the prime mover. Further, the power consumption of the motor generator 19 in the motor operation of the motor generator 19 is determined by the power received by the first power converter 25 a from the power system 18. With the above control, droop control is performed on the first power converter 25a, and power (generated power or consumed power (negative generated power)) of the motor generator 19 is feedback-controlled in this droop control.

As described above, according to the above-described configuration, it is possible to seamlessly switch between the self-sustaining operation and the grid interconnection operation of the bidirectional power conversion device 25, and to perform the rotational speed control and power control of the motor generator 19. Can be switched seamlessly. As a result, for example, in the marine hybrid propulsion system 10, when the electric propulsion mode is changed to the propulsion boost mode in which the thrust that can be supplied is large, it is not necessary to stop the system once. Moreover, since the electric operation and the electric power generation operation of the motor generator can be frequently switched every several seconds, it is possible to improve the fuel efficiency of the generator by absorbing load fluctuations such as waves.

(Embodiment 2)
In the mobile hybrid propulsion system 10 according to Embodiment 2, the controller 14 further includes a rate limiter 146 as shown in FIG. FIG. 5 is a block diagram schematically showing the controller 14 of the mobile hybrid propulsion system 10 according to the second embodiment.

The rate limiter 146 is connected to the mode selection unit 144 and the droop control unit 145 in the controller 14. When the power command value Pc input to the droop control unit 145 changes suddenly, the rate limiter 146 smoothes the change. For example, when the rotation speed control mode and the power control mode are switched, the input source of the power command value Pc is changed from the first power command value output unit 140 to the second power command value output unit 141, so that the power command value Pc Changes rapidly. At this time, the difference between the power command value and the previous power command value is obtained every predetermined time (calculation cycle), and when the difference exceeds a predetermined range, the difference is limited by a predetermined upper limit value and lower limit value. The power command value is continuously changed by adding the differences. Thereby, the change rate of electric power command value Pc is restrict | limited.

Here, the rate limiter 146 is used to limit the rate of change of the power command value Pc. However, the power command value input to the droop control unit 145 when switching between the power command value Pc from the first power command value output unit 140 and the power command value Pc from the second power command value output unit 141. As long as Pc is changed continuously, it is not limited to the rate limiter 146, and may be a first-order lag filter, for example.

According to the above configuration, the control mode of the motor generator 19 can be switched smoothly. That is, for example, in the rotational speed control mode, the electric power command value Pc is output based on the deviation Δn between the rotational speed command value nc corresponding to the operation information and the actual rotational speed value n of the motor generator 19. On the other hand, in the power control mode, a power command value Pc corresponding to the operation information is output. For this reason, the power command value Pc in the rotational speed control mode and the power command value Pc in the power control mode are greatly different. Therefore, when the power control mode and the rotation speed control mode are switched, the power command value Pc changes abruptly. Even in such a case, the change of the power command value input to the droop control unit 145 is smoothed by the rate limiter 146, so that the control mode can be switched smoothly.

In the above description, the change in the power command value is limited to a predetermined range by the rate limiter 146 other than when the control mode of the motor generator 19 is switched. However, the change of the power command value may be limited to a predetermined range by the rate limiter 146 only when the control mode of the motor generator 19 is switched.

(Embodiment 3)
The moving body hybrid propulsion system 10 according to the third embodiment is an example in which the moving body hybrid propulsion system 10 according to the first embodiment is applied to a ship. FIG. 6 is a block diagram schematically showing a mobile hybrid propulsion system 10 according to the third embodiment.

The hybrid propulsion system 10 further includes a thrust and power supply system 13 and a storage unit 15. The thrust and power supply system 13 is a system that is connected to the propeller 11 and the inboard power load 21 and supplies thrust (power) and power generated by the component devices 17, 18, and 19 to the loads 11 and 21. The component device is a device that generates rotational power or electric power, and includes a main machine 17, a main generator 18, and a motor generator 19. One or a plurality of main machines 17, main generators 18 and motor generators 19 are provided in the ship.

The main machine 17 is a main power source in the hybrid propulsion system 10, and for example, a prime mover such as an engine is used. The main machine 17 is connected to the propeller 11 and the motor generator 19 through a power transmission mechanism. The power transmission mechanism is constituted by, for example, a drive shaft of the propeller 11, a speed reducer 20, and a shaft of the main machine 17. The reduction gear 20 decreases the rotational speed of the power from the main engine 17 to increase the torque, and transmits the power to the propeller 11 and the motor generator 19.

The main generator 18 is a main power source that supplies electric power to the motor generator 19 and the inboard power load 21 of the ship, and is connected to the inboard bus 22. An inboard power load 21 and a motor generator 19 are connected to the inboard bus 22. Examples of the inboard power load 21 include a side thruster (not shown), an auxiliary machine (not shown), a console 23, an electric heater (not shown), and an electric lamp (not shown). The inboard power load 21 and the motor generator 19 are connected to a PMS (Power Management System) 24, and output a request for power required when the inboard power load 21 and the motor generator 19 operate to the PMS 24. The PMS 24 is connected to each device of the controller 14 and the supply system 13 in addition to the inboard power load 21 and the motor generator 19. The PMS 24 obtains the demand power for the hybrid propulsion system 10 based on the required power from each power load 19, 21 and outputs the demand power to the controller 14. The PMS 24 controls the stop and operation of each device in the supply system 13.

The motor generator 19 is connected to the propeller 11 and the main machine 17 through a power transmission mechanism. The power transmission mechanism includes a shaft of the motor generator 19, a drive shaft of the propeller 11, a speed reducer 20, and a shaft of the main machine 17. The motor generator 19 is connected to the main generator 18 and is connected to the inboard power load 21 via the inboard bus 22. When the motor generator 19 functions as an electric motor (electric operation), it receives electric power from the main generator 18 and generates rotational power. As a result, the rotational power is transmitted from the motor generator 19 to the propeller 11 via the speed reducer 20, and the propeller 11 rotates to generate thrust. On the other hand, when the motor generator 19 functions as a generator (power generation operation), the motor generator 19 generates power by receiving the rotational power of the main engine 17 and supplies the power to the inboard power load 21 via the inboard bus 22.

A power conversion device 25 is provided between the motor generator 19 and the main generator 18. The power converter 25 is a power converter that converts AC from the main generator 18 and the motor generator 19 bidirectionally. In other words, the power conversion device 25 includes the first power converter 25a and the second power converter 25b illustrated in FIG. The AC terminal of the first power converter 25 a is connected to the inboard bus 22, and the AC terminal of the second power converter 25 b is connected to the motor generator 19.

The storage unit 15 stores the operation mode of the hybrid propulsion system 10. There are a plurality of operation modes, which are set by a combination of the operation or stop of the main machine 17, the operation or stop of the main generator 18, and the motor operation, power generation operation or stop of the motor generator 19.

The propeller 11 is a propulsion device that imparts thrust to the ship, and one or more propellers 11 are provided in the ship. The propeller 11 is connected to the speed reducer 20. The propeller 11 receives the rotational power output from the main engine 17 and / or the motor generator 19 that is electrically operated via the speed reducer 20, and converts the rotational power into thrust. The thrust of the propeller 11 is controlled by the rotation speed of the propeller 11 adjusted by the speed reducer 20 and the pitch angle (blade angle) of the propeller 11 adjusted by a pitch angle adjusting mechanism (not shown).

The lever 12 is a control stick for the operator to input the demand thrust of the ship. For example, a throttle lever is used and is provided on the console 23. The lever 12 is connected to a PCS (Propulsion Control System) 26 and outputs an operation amount (operation information) of the lever 12 by the operator to the PCS 26. In addition to the lever 12, the PCS 26 is further connected to the controller 14, the control device of the main machine 17, and the pitch angle adjusting mechanism. The PCS 26 determines the demand thrust, the rotational speed of the main engine 17, and the pitch angle of the propeller 11 based on the operation amount of the lever 12. Then, the PCS 26 outputs the demand thrust to the controller 14, outputs the rotation speed of the main machine 17 to the control device of the main machine 17, and outputs the pitch angle of the propeller 11 to the pitch angle adjustment mechanism. The thrust of the propeller 11 is controlled by the rotation speed and pitch angle of the propeller 11.

The input unit 29 is connected to the controller 14 and is provided on the console 23 using, for example, a keyboard or a touch pad.

The controller 14, the PMS 24, and the PCS 26 may be configured with one control device or may be configured with three individual control devices. When these 14, 24 and 26 are constituted by one control device, the functions of the controller 14, the PMS 24 and the PCS 26 are realized by a program stored in the control device.

Next, the operation mode of the mobile hybrid propulsion system 10 will be described. 7A to 7E are block diagrams showing operation modes of the hybrid propulsion system 10 for a moving object. The operation mode has, for example, five modes shown in FIGS. 7A to 7E. Among these, the machine propulsion mode of FIG. 7A is an operation mode in which the motor generator 19 stops and the main engine 17 and the main generator 18 operate independently. The electric propulsion mode, the propulsion boost mode, and the parallel mode in FIGS. 7B to 7D are grid interconnection operation modes. The axis starting mode in FIG. 7E is a self-sustaining operation mode. Further, in the electric propulsion mode, it is necessary to control the rotational speed of the motor generator 19, and in the propulsion boost mode, the parallel mode, and the axial mode, it is necessary to control the electric power of the motor generator 19.

7A, the main engine 17 operates, the main generator 18 operates, and the motor generator 19 stops. In this machine propulsion mode, the main engine 17 supplies rotational power to the propeller 11 via the speed reducer 20. The main generator 18 supplies power to the inboard power load 21 (FIG. 1) via the inboard bus 22. As described above, the thrust of the propeller 11 is given by the rotational power of the main machine 17, and the power of the inboard power load 21 is given from the main generator 18.

7B, in the electric propulsion mode of FIG. 7B, the main machine 17 stops, the main generator 18 operates, and the motor generator 19 operates electrically. In this electric propulsion mode, the main generator 18 supplies power to the ship power load 21 via the ship bus 22 and supplies power to the motor generator 19 via the power converter 25. The motor generator 19 receives the electric power from the main generator 18 to generate rotational power, and supplies the rotational power to the propeller 11 via the speed reducer 20. For this reason, the thrust of the propeller 11 is given by the rotational power of the motor generator 19. Generally, since the output of the motor generator 19 is designed to be smaller than the output of the main engine 17, the supplyable thrust in the electric propulsion mode is smaller than that in the mechanical propulsion mode of FIG. 7A.

7C, the main engine 17 operates, the main generator 18 operates, and the motor generator 19 operates electrically. In the propulsion boost mode, the main generator 18 supplies electric power to the inboard power load 21 through the inboard bus 22 and also supplies electric power to the motor generator 19. The motor generator 19 and the main machine 17 supply rotational power to the propeller 11 via the speed reducer 20. Thus, since the thrust of the propeller 11 is given not only by the rotational power of the main engine 17 but also by the rotational power of the motor generator 19, the thrust that can be supplied in the propulsion bias mode is larger than that in the mechanical propulsion mode of FIG. 7A.

7D, in the parallel mode, the main machine 17 operates, the main generator 18 operates, and the motor generator 19 generates power. In this parallel mode, the main generator 18 supplies power to the inboard power load 21 via the inboard bus 22. The main machine 17 supplies rotational power to the propeller 11 and the motor generator 19. The motor generator 19 receives the rotational power from the main engine 17 and generates power, and supplies the power to the inboard power load 21 via the power converter 25 and the inboard bus 22. Thus, since electric power is supplied from the motor generator 19 to the inboard power load 21 in addition to the main generator 18, the power that can be supplied in the parallel mode is larger than that in the mechanical propulsion mode of FIG. 7A.

7E, the main engine 17 operates, the main generator 18 stops, and the motor generator 19 generates power. In this axial mode, the main engine 17 supplies rotational power to the propeller 11 and the motor generator 19. The motor generator 19 receives the rotational power from the main engine 17 and generates power, and supplies the power to the inboard power load 21 via the power converter 25 and the inboard bus 22. Thus, electric power is supplied only from the motor generator 19. When the output of the motor generator 19 is designed to be smaller than the output of the main generator 18, the power that can be supplied in the axial mode is smaller than that in the mechanical propulsion mode in FIG. 7A.

Next, the control method in each operation mode will be described. FIG. 8 is a block diagram schematically showing the controller 14 of the mobile hybrid propulsion system 10 according to the third embodiment. In FIG. 8, the rate limiter 146 is provided in the controller 14, but may not be provided as in the first embodiment.

In the electric propulsion mode shown in FIG. 7B, the main machine 17 is stopped and the motor generator 19 is electrically operated. In this case, the motor generator 19 supplies power to the propeller 11 to obtain a propulsive force. Since the motor generator 19 is the only power source of the propeller 11, it is necessary to control the rotational speed of the motor generator 19 in order to prevent the speed of the propeller 11 from being exceeded. Therefore, the mode selection unit 144 in FIG. 8 selects the rotation speed control mode in accordance with the rotation speed control mode command. As a result, the power command value Pc from the first power command value output unit 140 is input to the droop control unit 145. Therefore, as shown in the table of FIG. 11, in the electric propulsion mode, the first power converter 25a is droop-controlled by the droop characteristic line based on the rotation speed control mode.

However, the power control mode can also be selected in the electric propulsion mode in situations where it is clear that there is no fear of exceeding the speed of the propeller 11, such as when the sea conditions are calm or the thrust of the propeller 11 is relatively small. . In general, since electric power control has smaller fluctuations in electric power than rotation speed control, fuel efficiency can be improved. In this case, the power command value Pc from the second power command value output unit 141 may be input to the droop control unit 145.

In the propulsion boost mode shown in FIG. 7C, the main machine 17 is operating and the motor generator 19 is operating. For this reason, the main machine 17 and the motor generator 19 supply power to the propeller 11 to obtain a propulsive force. When a plurality of prime movers (main engine 17 and motor generator 19) are connected to the drive shaft of propeller 11 in this way, if both main machine 17 and motor generator 19 are in the rotational speed control mode, the control interferes and excessive There are problems such as load. For this reason, the number of revolutions of the main engine 17 with large power is controlled, and the motor generator 19 is controlled in electric power. Therefore, the mode selection unit 144 in FIG. 8 selects the power control mode according to the power control mode command. Thereby, the power command value Pc from the second power command value output unit 141 is input to the droop control unit 145. Therefore, as shown in the table of FIG. 11, in the propulsion boost mode, the first power converter 25a is droop-controlled by the droop characteristic line based on the power control.

However, in the propulsion boost mode, it is theoretically possible for the main engine 17 to control the thrust and to control the rotational speed of the motor generator 19. In this case, the power command value Pc from the first power command value output unit 140 may be input to the droop control unit 145.

In the axial mode shown in FIG. 7E, no other device that supplies power to the power system is connected. In this case, the electric power of the motor generator 19 is controlled so as to cover the demand. For this reason, in the mode selection part 144 of FIG. 8, a power control mode is selected according to the mode command of power control. Thereby, the power command value Pc from the second power command value output unit 141 is input to the droop control unit 145. Therefore, as shown in the table of FIG. 11, in the axial mode, the first power converter 25a is droop controlled by the droop characteristic line based on the power control.

In the parallel mode shown in FIG. 7D and the axial mode shown in FIG. 7E, the PMS 24 outputs a power generation request to each of the power generation facilities 18 and 19 so that the power supply satisfies the power demand. The mode selection unit 144 selects a power control mode in response to a power generation request from the PMS 24 as a power control mode command. Then, the power command value Pc from the second power command value output unit 141 is input to the droop control unit 145. Thereby, as shown in the table of FIG. 11, in the parallel mode and the axial mode, the first power converter 25a is droop controlled by the droop characteristic line based on the power control.

Next, the control method at the time of operation mode transition will be described. The operation mode of the hybrid propulsion system 10 is set based on, for example, the supply capability of the operation mode, fuel consumption, and redundancy. For example, it is set to an operation mode that has a supply capability greater than demand, good fuel consumption, and satisfies required redundancy. For this reason, it changes to the driving mode with the best fuel consumption, or changes to the driving mode that covers the demand. The transition of the operation mode is executed by an operator operating the input unit 29 or based on a power generation request from the PMS 24 or the like. When the input unit 29 is operated, a mode command for the control mode of the motor generator 19 corresponding to the operation mode is input from the input unit 29 to the mode selection unit 144 of the controller 14. The mode selection unit 144 selects the rotation speed control mode or the power control mode according to the mode command.

For example, when the electric propulsion mode or the propulsion boost mode is changed to the parallel mode or the axial mode, the operation mode of the motor generator 19 is switched from the electric operation to the power generation operation. At this time, the mode selection unit 144 in FIG. 8 selects a power control mode according to a power generation request from the PMS 24 or a mode command from the controller 14 or the input unit 29, and causes the motor generator 19 to perform a power generation operation.

In the case of transition from the electric propulsion mode to the propulsion boost mode, the parallel mode, or the axial mode, the control mode of the motor generator 19 is switched from the rotation speed control mode to the power control mode. At this time, the mode selection unit 144 in FIG. 8 selects a power control mode in accordance with a mode command from the controller 14 or the input unit 29.

According to the above embodiment, the propulsive force can be controlled by controlling the motor generator 19 in the rotation speed control mode in the electric propulsion mode.

Further, when a plurality of prime movers supply power to the propeller 11 as in the propulsion boost mode, the main engine 17 is controlled in rotational speed and the motor generator 19 is controlled in electric power. Thereby, problems such as overload can be prevented.

Furthermore, when the electric power is covered by the motor generator 19 that generates electricity as in the axial mode, the electric power of the motor generator 19 is controlled. Thereby, a power failure or an overload of the motor generator 19 can be prevented. When a power request is output from the PMS 24, the motor generator 19 is controlled in power. Thereby, a power failure or an overload of the motor generator 19 can be prevented.

(Embodiment 4)
In the mobile hybrid propulsion system 10 according to the fourth embodiment, the control mode of the motor generator 19 is set based on the load acting on the drive shaft of the propulsion device 11 or the periodic fluctuation of the rotation speed of the propulsion device 11. To do.

Specifically, the controller 14 detects the load acting on the drive shaft of the propeller 11 or the rotation speed of the propeller 11 with an appropriate sensor (not shown), and detects the periodic fluctuation. Usually, in order for a ship to propel, the propeller 11 rotates while receiving a load. However, when sea conditions such as waves are bad, the propeller 11 is in a state of floating on the sea surface (propeller racing). Thereby, the load which acts on the propeller 11 falls, or the rotation speed of the propeller 11 becomes very large. Since this propeller racing occurs repeatedly when the hull sways, the load and the rotational speed fluctuate periodically.

Therefore, the controller 14 detects the periodic fluctuation of the load or the fluctuation of the rotation speed. When the periodic fluctuation amount (amplitude of fluctuation) is equal to or larger than a predetermined threshold, the mode selection unit 144 in FIG. 8 selects the rotation speed control mode and the power command from the first power command value output unit 140. The value Pc is selected and output to the droop control unit 145. As a result, the motor generator 19 is controlled in rotational speed, and the hybrid propulsion system 10 is operated in the electric propulsion mode.

Thus, the main machine 17 stops and the motor generator 19 is electrically operated, so that the motor generator 19 rotates the propeller 11. Since the rotational speed of the motor generator 19 is controlled, the rotational speed of the propeller 11 is kept constant. Therefore, excessive speed of the propeller 11 can be prevented.

(Embodiment 5)
The mobile hybrid propulsion system 10 according to the fifth embodiment selects the control mode of the motor generator 19 based on the rotational speed of the drive shaft of the propulsion unit 11. FIG. 9 is a block diagram schematically showing a mobile hybrid propulsion system 10 according to the fifth embodiment.

As shown in FIG. 9, the controller 14 detects the rotational speed of the drive shaft that drives the propulsion unit 11 by the rotational speed detector 11a. When the rotation speed is equal to or higher than a predetermined threshold, as shown in FIG. 8, mode selection unit 144 selects power command value Pc from first power command value output unit 140 and outputs it to droop control unit 145. . As a result, the motor generator 19 is controlled in rotational speed, thereby preventing the speed of the propeller 11 from being exceeded. However, when a plurality of prime movers supply power to the propeller 11 as in the propulsion boost mode, the main engine 17 may be controlled in rotational speed and the motor generator 19 may be controlled in electric power.

(Embodiment 6)
The mobile hybrid propulsion system 10 according to the sixth embodiment temporarily invalidates the rotational speed command or the power command from the lever 12 when the control mode is switched. FIG. 10 is a block diagram schematically showing the controller 14 of the mobile hybrid propulsion system 10 according to the sixth embodiment. In FIG. 10, the rate limiter 146 is provided in the controller 14, but it may not be provided as in the first embodiment.

The lever 12 is an input device for the rotational speed command value and the power command value. When the rotational speed of the motor generator 19 is controlled, the rotational speed command value generation unit 142 of the first power command value output unit 140 generates a rotational speed command value based on the operation amount of the lever 12. When the motor generator 19 is subjected to power control, the second power command value output unit 141 sets a power command value based on the operation amount of the lever 12. However, when the control mode of the motor generator 19 is switched, the rotation speed command and the power command input from the lever 12 are temporarily invalidated.

Specifically, for example, when an operation for changing the operation mode of the hybrid propulsion system 10 to the electric propulsion mode is performed on the input unit 29, a mode command is input from the input unit 29 to the mode selection unit 144. The mode selection unit 144 switches from the power control mode to the rotation speed control mode based on the mode command. As a result, the power command value Pc output from the mode selection unit 144 is switched from the power command value from the second power command value output unit 141 to the power command value from the first power command value output unit 140. Then, the lever position determination unit 147 sets “NO” in the first switching unit 149. As a result, the rotational speed command value nc from the rotational speed command value generation unit 142 is not input to the PID control unit 143, and the setting of the rotational speed command value nc based on the operation amount of the lever 12 is invalidated.

Further, when “NO” is set in the first switching unit 149, the actual value n of the rotational speed of the motor generator 19 at the time immediately before switching is set as a temporary rotational speed command value from the first memory 148 to the PID control unit. 143 is input. In the PID control unit 143, a temporary power command value is generated by a deviation between the temporary rotational speed command value and the actual rotational speed value from the motor generator 19, differentiation processing, and integration processing.

The first power command value output unit 140 includes an integration element. Thus, in the integration process of the PID control unit 143, when switching from the power control mode to the rotation speed control mode, the provisional power command value is set to the integration element so that it matches the actual power transfer to and received from the grid immediately before the switching. Set the value.

And the droop control part 145 sets a droop characteristic line based on the temporary electric power command value input from the PID control part 143, and controls the 1st power converter 25a using this droop characteristic line. Thereby, droop control is continued while preventing a sudden change in the power command value.

Thus, during the invalidation, the rotation speed command value nc based on the operation amount of the lever 12 is not output to the PID control unit 143 but is input to the lever position determination unit 147. Then, the lever position determination unit 147 compares the rotation speed command value nc with the temporary rotation speed command value in the first memory 148. Then, until the rotational speed command value nc matches the temporary rotational speed command value, or when the lever 12 gives a discrete operation amount, the lever 12 is the closest value to the temporary rotational speed command value. Is operated, the lever position determination unit 147 sets “YES” in the first switching unit 149. Thereby, the rotational speed command value nc from the rotational speed command value generation unit 142 is input to the PID control unit 143, and the invalidation of the lever 12 is released.

On the other hand, when an operation for changing the operation mode of the hybrid propulsion system 10 from the electric propulsion mode is performed on the input unit 29, a mode command is output from the input unit 29 to the mode selection unit 144. The mode selection unit 144 switches from the rotation speed control mode to the power control mode based on the mode command. As a result, the power command value Pc output from the mode selection unit 144 is switched from the power command value from the first power command value output unit 140 to the power command value from the second power command value output unit 141. Then, the lever position determination unit 147 sets “NO” in the second switching unit 151. Thereby, since the power command value Pc from the second power command value output unit 141 is not input to the droop control unit 145, the setting of the power command value Pc by the operation amount of the lever 12 is invalidated.

In addition, when “NO” is set in the second switching unit 151, the actual value P of the power supplied to and received from the system immediately before switching is input from the second memory 150 to the droop control unit 145 as a temporary power command value. The As a result, a droop characteristic line is set based on the provisional power command value Pc, and the first power converter 25a is controlled using the droop characteristic line, and droop control is performed while preventing a sudden change in the power command value. Will continue.

Thus, during the invalidation, the power command value Pc based on the operation amount of the lever 12 is not output to the droop control unit 145 but is input to the lever position determination unit 147. Then, the lever position determination unit 147 compares the power command value Pc with the temporary power command value in the second memory 150. When the lever 12 is operated until the power command value Pc matches the temporary power command value, or when the lever 12 gives a discrete operation amount, the lever 12 is operated to the value closest to the temporary power command value. The lever position determination unit 147 sets “YES” in the second switching unit 151. Thereby, the power command value Pc from the second power command value output unit 141 is input to the droop control unit 145, and the invalidation of the lever 12 is released.

According to the above configuration, the common lever 12 is used for the input of the rotational speed command value and the input of the power command value. Thereby, the operator can operate with one lever 12 without changing the lever 12 according to the operation mode of the hybrid propulsion system 10 or the control mode of the motor generator 19.

Also, the lever 12 is invalidated when the control mode of the motor generator 19 is switched. Thereby, it is possible to prevent a command value not intended by the operator from being input.

As shown in FIG. 10, the mobile hybrid propulsion system 10 may further include a display unit 28 provided on the console 23. In this case, the invalidation information is displayed on the display unit 28 while the lever 12 is invalidated. Thereby, it is possible to notify the operator that the lever 12 is invalidated.

Also, the lever 12 can be used as a device for inputting not only the motor generator 19 but also a rotational speed command or a fuel supply amount command of a prime mover (main machine 17). For example, the operation area of the lever 12 can be divided into a first part, a second part, and a third part in order from the stop position. When the lever 12 is in the first portion, the electric propulsion mode is set, and the motor generator 19 is electrically driven in the rotation speed control mode or the power control mode. When the lever 12 is in the second portion, the parallel mode is set, the main engine 17 is controlled in rotation speed or the fuel supply amount, and the motor generator 19 is caused to generate power in the power control mode. When the lever 12 is in the third portion, the propulsion boost mode is set, the main engine 17 is controlled in rotation speed or fuel supply amount, and the motor generator 19 is electrically driven in the power control mode.

Thus, as the operation position of the lever 12 is moved away from the stop position, the propeller thrust increases, and necessary mode transitions are simultaneously performed according to the thrust. For this reason, it is excellent in the operativity of an operator.

Also, the lever 12 can be used as a device for inputting the blade angle (pitch) of the propeller 11. The propeller 11 is a variable pitch propeller (CPP) 11. The rotational speed of the prime mover (main machine 17) is set to a predetermined value. Further, the relationship between the operation amount of the lever 12 and the blade angle of the propeller 11 is determined in advance. Based on this predetermined relationship, the blade angle of the propeller 11 corresponding to the amount of operation of the lever 12 by the operator is obtained. Then, the blade angle is output to a pitch angle adjusting mechanism (not shown), and the blade angle of the propeller 11 is controlled. Thus, since the blade angle of the propeller 11 can also be set by the lever 12, the operability of the operator is excellent.

Also, the lever 12 can be used as a device for inputting the rotational speed command value of the prime mover (main machine 17) and the blade angle (pitch) of the propeller 11. The propeller 11 is a variable pitch propeller 11. Further, the relationship (combination curve) between the operation amount of the lever 12 and the rotational speed of the prime mover and the blade angle of the propeller 11 is determined in advance. Based on this predetermined combination curve, the rotational speed of the prime mover and the blade angle of the propeller 11 corresponding to the operation amount of the lever 12 are obtained. Then, the blade angle is output to the pitch angle adjusting mechanism, and the blade angle of the propeller 11 is controlled. Further, the rotational speed of the prime mover is controlled by the rotational speed command value. As described above, the speed of the prime mover and the blade angle of the propeller 11 can be simultaneously set by the lever 12, so that the hybrid propulsion system 10 can be controlled in a state where the efficient rotation speed and blade angle are maintained. .

Note that all of the above embodiments may be combined with each other as long as they do not exclude each other.

From the above description, many modifications and other embodiments of the present invention are apparent to persons skilled in the art. Accordingly, the foregoing description should be construed as illustrative only and is provided for the purpose of teaching those skilled in the art the best mode of carrying out the invention. The details of the structure and / or function may be substantially changed without departing from the spirit of the invention.

The mobile hybrid propulsion system of the present invention is useful as a mobile hybrid propulsion system capable of seamlessly switching the control of the bidirectional power converter 25.

10 Hybrid propulsion system 11 Propeller (propulsion unit)
14 Controller 17 Main machine 18 Main generator (power system)
DESCRIPTION OF SYMBOLS 19 Motor generator 25 Power converter 25a 1st power converter 25b 2nd power converter 140 1st power command value output part 141 2nd power command value output part 144 Mode selection part 145 Droop control part

Claims (22)

A motor generator connected to a drive shaft for driving a propulsion device for propelling a moving body by a rotational force so that power can be transmitted;
A first power converter having an AC terminal connected to the power system and a DC terminal connected to the DC intermediate part;
A second power converter having a DC end connected to the DC intermediate portion and an AC end connected to the motor generator;
A first power command value output unit capable of setting a rotational speed command value and outputting a power command value based on a deviation of the rotational speed of the motor generator from the set rotational speed command value;
A power command value can be set, and a second power command value output unit that outputs the set power command value;
A mode selection unit that selects and outputs a power command value from the first power command value output unit and a power command value from the second power command value output unit;
A droop control unit that droop-controls the first power converter based on a power command value output from the mode selection unit;
And a second power converter control unit configured to control the second power converter so that the voltage of the DC intermediate unit is constant. The droop control unit generates, based on the power command value, the frequency of the power system and the generated power or electric power of the motor generator that is given or received by the first power converter to the power system (hereinafter referred to as a pair). The power supply / received power) is configured to be controlled so as to be one point on a droop characteristic line indicating a relationship between a frequency target value of the power system and a target value of the power supplied / received to the system. The mobile hybrid propulsion system described. The droop characteristic line is set to a power command value for a standard frequency of the power system, and is smaller than a power command value for a frequency higher than the standard frequency from a generated power or a power command value of the motor generator. The mobile body according to claim 2, wherein the moving body is set to a large electric power and is set to a power generated by the motor generator that is larger than a power command value or a motor power that is smaller than a power command value for a frequency lower than the standard frequency. Hybrid propulsion system. The movement according to claim 2 or 3, wherein the droop control unit is configured to control the frequency of the power system so as to be a frequency obtained from the actual power exchanged with the system and the droop characteristic line. Body hybrid propulsion system. The said droop control part is comprised so that the said system | strain transmission / reception power may be controlled so that it may become the said system | strain transmission / reception power calculated | required from the frequency of the said said power system and the said droop characteristic line. The hybrid propulsion system for mobile units described in 1. When the power command value output from the mode selection unit switches between the power command value from the first power command value output unit and the power command value from the second power command value output unit, the droop control The hybrid propulsion system for a moving body according to any one of claims 2 to 4, wherein the power command value input to the unit is configured to change continuously. The mobile hybrid propulsion system according to claim 6, further comprising a rate limiter that limits the change in the power command value output from the mode selection unit and inputs the command to the droop control unit. A prime mover connected to the drive shaft for driving the propulsion unit so as to be capable of transmitting power;
The mode selection unit is configured to select and output a power command value from the second power command value output unit when the prime mover operates and the rotation speed is controlled. The hybrid propulsion system for a moving body according to any one of the above. When no other device that supplies power to the power system is connected, the mode selection unit is configured to select and output a power command value from the second power command value output unit, The mobile hybrid propulsion system according to any one of claims 2 to 7. The mobile body has a power management system that outputs a power generation request to each power generation facility so that the power supply satisfies the power demand,
The mode selection unit is configured to select and output a power command value from the second power command value output unit when receiving the power generation request from the power management system. The hybrid propulsion system for a moving body according to any one of the above. When a load acting on the drive shaft that drives the propulsion unit or a periodic variation of the rotation speed of the propulsion unit is detected, and the amplitude of the variation is equal to or greater than a predetermined threshold, the mode selection unit The hybrid propulsion system for a moving body according to any one of claims 2 to 7, configured to select and output a power command value from a first power command value output unit. When the rotational speed of the drive shaft that drives the propulsion device is detected and the rotational speed is greater than or equal to a predetermined threshold, the mode selection unit selects a power command value from the first power command value output unit. The hybrid propulsion system for a moving body according to any one of claims 2 to 7, wherein the hybrid propulsion system is configured to output the A lever,
The first power command value output unit sets the rotation speed command value based on an operation amount of the lever,
The hybrid propulsion of the moving body according to any one of claims 2 to 12, wherein the second power command value output unit is configured to set the power command value based on an operation amount of the lever. system. When the power command value output from the mode selection unit switches between the power command value from the first power command value output unit and the power command value from the second power command value output unit, Invalidate the setting of the rotation speed command value or the power command value by operation,
The actual rotational speed of the motor generator at the time immediately before the switching is set to a temporary rotational speed command value, and the rotational speed command value from the first power command value output unit corresponding to the operation amount of the lever is The lever is moved until it coincides with the temporary rotational speed command value, or when the lever gives a discrete operational amount to a position where the operational amount corresponds to a value closest to the temporary rotational speed command value. Cancel the invalidation when operated, or
The actual transmission / reception power to / from the system immediately before the switching is set to a temporary power command value, and the power command value from the second power command value output unit corresponding to the lever operation amount is the temporary power command value. When the lever is operated until the command value is reached, or when the lever gives a discrete operation amount, the operation amount reaches the position corresponding to the value closest to the temporary power command value. The hybrid propulsion system for a moving body according to claim 13, which is configured to cancel the conversion. The first power command value output unit includes an integral element, and the power command value output from the mode selection unit is changed from the power command value from the second power command value output unit to the first power command value output unit. When switching to a power command value, the value of the integral element is set so that the power command value from the first power command value output unit coincides with the actual power supplied to the grid immediately before the switching. 15. The hybrid propulsion system for a moving body according to claim 14, wherein A display unit;
The invalidation is configured to be displayed on the display unit while the setting of the rotation speed command value or the power command value by the operation of the lever is invalidated. Mobile hybrid propulsion system. The hybrid propulsion system for a moving body according to any one of claims 13 to 16, wherein the moving body is a ship. 18. The mobile hybrid propulsion system according to claim 17, wherein the lever further serves as a rotational speed command or a fuel supply amount command for a prime mover connected to the drive shaft so as to be capable of transmitting power. The propulsion device is a variable pitch propeller,
The hybrid propulsion system for a moving body according to claim 17, wherein the lever further serves as a blade angle command of the variable pitch propeller. The propulsion device is a variable pitch propeller,
The lever further has a function of simultaneously commanding a rotational speed command of a prime mover connected to the drive shaft so that power can be transmitted and a blade angle command of the variable pitch propeller along a predetermined combination curve. Item 18. A mobile hybrid propulsion system according to Item 17. A motor generator connected to a drive shaft for driving a propulsion device for propelling a moving body by a rotational force so that power can be transmitted;
A first power converter having an AC terminal connected to the power system and a DC terminal connected to the DC intermediate part;
A second power converter having a direct current end connected to the direct current intermediate portion and an alternating current end connected to the motor generator, and a control method of a hybrid propulsion system for a moving body comprising:
A first power command value output step for setting a rotational speed command value and outputting a power command value based on a deviation of the rotational speed of the motor generator from the set rotational speed command value;
A second power command value output step for setting the power command value and outputting the set power command value;
A mode selection step of selecting and outputting the power command value of the first power command value output step and the power command value of the second power command value output step;
A droop control step for performing a droop control on the first power converter based on the power command value output by the mode selection step;
And a second power converter control step of controlling the second power converter so that the voltage of the DC intermediate part is constant. In the droop control step, based on the power command value, the frequency of the power system and the generated power or electric power of the motor generator that is given or received by the first power converter to the power system (hereinafter referred to as the pair The mobile hybrid according to claim 21, wherein control is performed so that a system transmission / reception power is a single point on a droop characteristic line indicating a relationship between a frequency target value of the power system and a target value of the power transmission / reception power. Propulsion system control method.

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