JP7769465B2 - Power generation control device - Google Patents

Description

The present invention relates to a power generation control device.

Patent Document 1 discloses an electrically driven vehicle equipped with an engine-driven generator unit, in which a generator switch is provided on the instrument panel as an operating means for requesting operation of the generator unit.

In the electrically driven vehicle described in Patent Document 1, when the power generation switch is ON, there is a request to operate the power generation device.

International Publication No. 2011/089726

However, in the electrically driven vehicle described in Patent Document 1, when the power generation switch is ON, the power generation device generates electricity, but this does not reflect the driver's wishes, such as wanting to maintain a high state of charge in the battery or wanting to travel to a power supply facility while conserving fuel.

The present invention was made in consideration of the above-mentioned circumstances, and aims to provide a power generation control device that can perform charging in accordance with the wishes of the occupant.

The present invention provides a power generation control device for an electric vehicle including a driving motor, a battery that supplies power to the motor, a generator that generates power to charge the battery, and an internal combustion engine that drives the generator, the device comprising: a control unit that controls the operating state of the internal combustion engine in either an automatic power generation mode that controls the operating state of the internal combustion engine in accordance with the remaining capacity of the battery, or a manual power generation mode that starts operation of the internal combustion engine in accordance with an operation that requests power generation by the generator; and a power generation state setting unit that allows a driver to set the power generation state in the manual power generation mode, the generator, the internal combustion engine, the control unit, and the power generation state setting unit are integrated into one generator unit that is detachable from the electric vehicle and can be removed from the electric vehicle and used as a standalone power generation device that supplies power to electrical equipment other than electrical equipment provided on the electric vehicle, and the power generation state setting unit sets S as an index corresponding to a target power generation amount. The power generation state in the manual power generation mode can be set by the occupant by specifying one or more of OC, charging time, driving distance, and the amount of power generation required to reach the destination, and the power generation state setting unit is configured to allow the occupant to set the power generation state in the manual power generation mode by the occupant setting in stages the target value for the output power to be output by the generator.

This invention provides a power generation control device that can perform charging in accordance with the occupant's wishes.

FIG. 1 is a diagram showing the configuration of a vehicle according to an embodiment of the present invention. FIG. 2 is a structural diagram of a vehicle according to an embodiment of the present invention, showing a state in which the generator unit has been removed. FIG. 3 is a diagram showing an example of a display on an operation panel of a vehicle according to an embodiment of the present invention. FIG. 4 is a diagram showing an example of a power generation termination condition setting screen on the operation panel of the vehicle according to the embodiment of the present invention. FIG. 5 is an example of a timing chart when the power generation in the vehicle according to the embodiment of the present invention is changed. FIG. 6 is an example of a timing chart when the power generation mode is switched in a vehicle according to an embodiment of the present invention. FIG. 7 is a flowchart illustrating the operation of the GCU according to one embodiment of the present invention. FIG. 8 is a flowchart illustrating the flow of the gradual change process of output power executed by the GCU according to one embodiment of the present invention. FIG. 9 is a flowchart illustrating the flow of power generation stopping processing executed by a GCU according to an embodiment of the present invention. FIG. 10 is a flowchart illustrating the flow of a power generation stimulation process executed by a GCU according to an embodiment of the present invention. FIG. 11 is a flowchart showing a modified example of the power generation evacuation process executed by the GCU according to an embodiment of the present invention.

A power generation control device according to one embodiment of the present invention is a power generation control device for an electric vehicle equipped with a traction motor, a battery that supplies power to the motor, a generator that generates power to charge the battery, and an internal combustion engine that drives the generator. It is characterized by including a control unit that controls the operating state of the internal combustion engine in either an automatic power generation mode that controls the operating state of the internal combustion engine depending on the remaining battery capacity, or a manual power generation mode that starts operation of the internal combustion engine in response to an operation that requests power generation by the generator, and a power generation state setting unit that allows the occupant to set the power generation state in the manual power generation mode. This allows the power generation control device according to one embodiment of the present invention to perform charging that reflects the occupant's intentions.

An electric vehicle according to one embodiment of the present invention will be described below with reference to the accompanying drawings.

As shown in FIG. 1, the vehicle 10 includes wheels 12, a motor generator (hereinafter referred to as "MG") 20 for propelling the vehicle, a battery 30 for propelling the vehicle, a generator unit 40, and an ECU (Electronic Control Unit) 100. The vehicle 10 is an electric vehicle that runs on power from the MG 20.

MG20 is a rotating electric machine that functions as both an electric motor and a generator, and is connected to wheels 12 via drive shaft 11. MG20 is provided with INV21. MG20 is connected to battery 30 via INV21. Under the control of ECU 100, INV21 converts DC power output from battery 30 into AC power and outputs it to MG20.

The battery 30 is a secondary battery such as a lithium-ion battery, and supplies power to the MG 20, the generator 42 (described below), and electrical components (not shown). The battery 30 also stores the power generated by the generator 42 and the MG 20.

The ECU 100 is composed of a computer unit equipped with a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), flash memory for storing backup data, input ports, and output ports.

The ROM of this computer unit stores various constants, maps, etc., as well as programs that cause the computer unit to function as ECU 100. In other words, the CPU uses RAM as a working area to execute the programs stored in ROM, causing this computer unit to function as ECU 100 in this embodiment.

The ECU 100 controls the MG 20 via the INV 21. The ECU 100 is connected to the INV 21, various sensors such as the battery sensor 31, and various devices such as the car navigation device 80. The ECU 100 is connected to a GCU (Generator Control Unit) 45 (described below) via a CAN communication line 101, and exchanges data with the GCU 45.

The battery sensor 31 detects the amount of charge stored in the battery 30, i.e., the state of charge (SOC). The battery sensor 31 outputs a signal indicating the detection result to the ECU 100.

The car navigation device 80 includes a display unit that displays map information, etc., a touch panel input unit that allows the occupant as the operator to input information such as a destination, a current position detection unit that detects the current position of the vehicle 10, a route search unit that searches for a route from the current position of the vehicle 10 to the destination, a distance calculation unit that calculates the distance from the current position of the vehicle 10 to the destination, a charging facility search unit that searches for charging facilities on the route from the current position to the destination based on map information, etc., and a memory unit that stores history information, etc. The car navigation device 80 sets the destination input by the occupant via the input unit as the destination of the vehicle 10.

The car navigation device 80 is connected to the ECU 100 for two-way communication and is configured to be able to acquire various information from the ECU 100, such as vehicle speed, SOC, and past electricity consumption, and is also configured to be able to transmit to the ECU 100 information such as the distance from the current location to the destination calculated by the distance calculation unit, and charging facilities located on the route to the destination. In this embodiment, the destination set in the car navigation device 80 and the charging facilities located on the route to the destination are collectively referred to as the target point.

The generator unit 40 includes an engine 41 as an internal combustion engine, a starter (not shown) that is a starting device for starting the engine 41, a generator 42, an INV 43, a fuel tank 44, and a GCU 45 as a control unit.

The generator unit 40 is configured as an integrated unit that integrates the engine 41, starter, generator 42, INV 43, fuel tank 44, and GCU 45. The generator unit 40, with these various components integrated, is configured to be detachable from the vehicle 10 using pull-out rails 14 fixed to the vehicle 10, as shown in FIG. 2. In this embodiment, the generator unit 40 is provided at the rear of the vehicle and is configured to be pulled out from the rear toward the rear of the vehicle. The generator unit 40 is not limited to being provided at the rear of the vehicle, but may also be provided at the front or side of the vehicle, and the direction in which it is pulled out from the vehicle is not limited to being at the rear of the vehicle, but may also be toward the front or side of the vehicle.

When the generator unit 40 is mounted on the vehicle 10, it is secured to the vehicle 10 by a locking mechanism (not shown). When removed from the vehicle 10, the generator unit 40 functions as a power generation device that supplies power to electrical equipment other than the electrical equipment installed on the vehicle 10.

The generator unit 40 has a converter that converts the DC power output from the INV 43 or the AC power output from the generator 42 into power that conforms to a commercial power source, an outlet for supplying the commercial power source-conforming power to the outside, and an operation panel 70A that functions in the same way as the operation panel 70 described below. The generator unit 40 may also have a USB port for charging electrical devices that comply with the USB (Universal Serial Bus) standard, and a cigarette lighter socket. The generator unit 40 is also provided with an emergency stop button for emergency stopping the operation of the engine 41 and generator 42.

Engine 41 has at least one cylinder. In this embodiment, engine 41 is configured to perform a series of four strokes for each cylinder: an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke.

The generator 42 is connected to the crankshaft of the engine 41 via driving members such as gears, and functions as a generator that generates electricity using the power of the engine 41. In other words, the generator 42 is an internal combustion engine-driven generator. The generator 42 is equipped with an inverter (hereinafter referred to as "INV") 43. The generator 42 is connected to the battery 30 via the INV 43.

Under the control of the GCU 45, the INV 43 converts the AC power output from the generator 42 into DC power and outputs it to the battery 30. The fuel tank 44 is a tank that stores fuel consumed by the engine 41. The fuel tank 44 is provided with a fuel filler opening. This fuel filler opening is exposed to the outside of the vehicle when the generator unit 40 is pulled out to the outside of the vehicle. Refueling is performed by pulling the generator unit 40 out of the vehicle. For this reason, in this embodiment, a fuel filler opening is not provided on the vehicle 10.

The GCU 45 is composed of a computer unit equipped with a CPU, RAM, ROM, flash memory for storing backup data, input ports, and output ports.

The ROM of this computer unit stores various constants, maps, etc., as well as a program that causes the computer unit to function as GCU 45. In other words, the CPU uses RAM as a working area to execute the program stored in ROM, causing this computer unit to function as GCU 45 in this embodiment.

The GCU 45 controls the engine 41 via an injector and throttle valve (not shown). The GCU 45 controls the generator 42 via the INV 43.

The GCU 45 controls the operating state of the engine 41 in either an automatic power generation mode, in which the operating state of the engine 41 is controlled in accordance with the detection results of the battery sensor 31 obtained from the ECU 100, or a manual power generation mode, in which the operation of the engine 41 is started in response to an operation by the occupant requesting power generation by the generator 42.

An operation panel 70 is connected to the GCU 45. The operation panel 70 is provided in a location that is easy for the driver to operate and that is easily visible, such as the instrument panel or center console of the vehicle 10. The operation panel 70 may also be provided as one aspect of the display screen of the car navigation device 80.

In this embodiment, the operation panel 70 is configured as a touch panel consisting of a liquid crystal display device and a touchpad. The operation panel 70 in this embodiment constitutes the power generation state setting unit of the present invention.

In FIG. 3, the operation panel 70 has a remaining fuel amount display area 71, a generated power display area 72, an SOC display area 73, a power generation switch 74, power generation control switches 75a and 75b, a power generation control status display area 76, and a setting switch 77.

The remaining fuel display area 71 displays the remaining amount of fuel stored in the fuel tank 44. The generated power display area 72 displays the output power [kW] of the generator 42. The SOC display area 73 displays the SOC [%] of the battery 30. Note that the SOC display area 73 may display the SOC of the battery 30 as is, or may display a value normalized by the lower limit SOC and upper limit SOC described below.

The power generation switch 74 is a switch that allows the occupant to operate the generator 42 to request power generation in manual power generation mode. In other words, when the power generation switch 74 is turned on in manual power generation mode, power generation by the generator 42 begins. The power generation control switches 75a and 75b are switches that switch between automatic power generation mode and manual power generation mode.

When the power generation control switch 75a is pressed, the automatic power generation mode switches to manual power generation mode (non-power generation state). In manual power generation mode, when the power generation control switch 75a is pressed again, the target value (also called "target power") for the output power of the generator 42 increases in stages, and cyclical selection is made, such as returning from manual power generation mode to automatic power generation mode.

In this embodiment, the target output power is set in stages of 1.0 kW (power saving), 2.0 kW (high speed), and 3.0 kW (emergency). In other words, each time the power generation control switch 75a is pressed, the mode switches in the following order: automatic power generation mode, manual power generation mode (non-power generation state), power saving (output power = 1.0 kW), high speed (output power = 2.0 kW), emergency (output power = 3.0 kW), and then returns to automatic power generation mode.

The smallest target value for the generator 42 output power is set to the output power of the generator 42 when the engine 41 is operating in a state with the highest fuel efficiency. When the power generation control switch 75a is pressed to switch from automatic power generation mode to manual power generation mode, it may be assumed that an operation to request power generation by the generator 42 has also been performed, just as when the power generation switch 74 is pressed.

When the power generation control switch 75b is pressed, a cyclical selection is made in the opposite direction to when the power generation control switch 75a is pressed. The power generation control switches 75a and 75b can be operated even while the generator 42 is generating power. Therefore, even while the generator 42 is generating power, the power generation mode and the target power of the generator 42 can be changed by operating the power generation control switches 75a and 75b.

The operation panel 70 may be provided with either a power generation control switch 75a or 75b. The power generation control status display area 76 displays the selected status of the power generation control switch 75a or 75b.

In the automatic power generation mode, when the vehicle 10 is powered on, if the SOC of the battery 30 falls below the lower limit SOC, the engine 41 is started to start charging the battery 30, and if the SOC of the battery 30 rises above the upper limit SOC, the engine 41 is stopped to end charging the battery 30. The lower limit SOC and upper limit SOC are values adapted to the specifications of the battery 30 and are stored in the ROM of the ECU 100.

In manual power generation mode, regardless of whether the vehicle 10 is powered on or off, when the power generation switch 74 is pressed, the engine 41 starts, power generation by the generator 42 begins, the battery 30 is charged, and when a power generation termination condition is met as an indicator corresponding to the target power generation amount, the engine 41 is stopped and charging of the battery 30 is terminated.

The power generation termination condition is one or more conditions selected from the following: a first condition that is met when the SOC of the battery 30 reaches the target SOC; a second condition that is met when the charging time reaches a set time; a third condition that is met when the amount of power generated is sufficient to allow the vehicle 10 to travel a set distance; and a fourth condition that is met when the amount of power generated is sufficient to reach the target point obtained from the car navigation device 80.

If multiple conditions are selected as the power generation termination condition, the power generation termination condition will be met if any of the selected conditions is met. Furthermore, if the SOC of the battery 30 becomes equal to or greater than the upper limit SOC, the engine 41 will be stopped and charging of the battery 30 will end, even if the selected power generation termination condition is not met.

The power generation termination condition is selected on the power generation termination condition setting screen shown in Figure 4. The power generation termination condition setting screen is displayed on the operation panel 70 when the setting switch 77 is pressed on the display screen shown in Figure 3. The power generation termination condition setting screen is provided with selection buttons 88a, 88b, 88c, and 88d for selecting each of the first through fourth conditions, and switches 89a, 89b, 89c, and 89d for setting the target value for each condition.

In this embodiment, switch 89a can select the target value for the first condition between the lower limit SOC and the upper limit SOC, or between 0% and 100% normalized between the lower limit SOC and the upper limit SOC. Switch 89b can select the target value for the second condition, for example, at 1 minute intervals from 10 minutes or at 10 minute intervals.

Switch 89c allows the user to select the target value for the third condition, for example, from 10 km in 1 km or 10 km intervals. Switch 89d allows the user to select a target point as the target value for the fourth condition from among the destination set in the car navigation device 80 and charging facilities located on the route from the current location to the destination. The power generation amount for the third and fourth conditions can be determined, for example, from past driving history and the SOC history of the battery 30.

In FIG. 3, the power generation switch 74 and power generation control switches 75a and 75b may be configured as mechanical switches provided on the instrument panel, center console, or steering wheel of the vehicle 10. In this case, the power generation switch 74 and power generation control switches 75a and 75b may be configured as push switches, for example. The power generation control switches 75a and 75b may also be configured as a single rotary switch.

The power generation switch 74 may also be provided on the remote control key of the vehicle 10, or may be provided as a touch icon on the display screen of an application on a mobile device such as a smartphone.

As shown in Figure 5, if the target power is not being output from the generator 42, the GCU 45 controls the operating state of the engine 41 by gradually changing the output power (also called "generated power") of the generator 42 so that the output power of the generator 42 becomes the target power. Figure 5 shows an example where the target power is higher than the current output power.

During the period in which the output power of the generator 42 is gradually changed, the GCU 45 controls the operating state of the engine 41 so that a first period T1 in which the output power of the generator 42 changes toward the target power and a second period T2 in which the output power of the generator 42 changes less than in the first period T1 are continuously repeated.

In this embodiment, during the first period T1, the GCU 45 controls the operating state of the engine 41 so that the output power of the generator 42 changes by a fluctuation of 1 kW per second. During the second period T2, the GCU 45 controls the operating state of the engine 41 so that the output power of the generator 42 does not change. In this embodiment, the first period T1 and the second period T2 are both set to 1 second, but this is an example and is not limited to 1 second; any time can be set, and the first period T1 and the second period T2 may also be set to different times.

In addition, during the second period T2, the GCU 45 may control the operating state of the engine 41 so that the output power of the generator 42 changes with a smaller fluctuation amount than during the first period T1, or may control the operating state of the engine 41 so that the output power of the generator 42 changes away from the target power with a smaller fluctuation amount than during the first period T1.

In this way, when changing the output power of the generator 42, the GCU 45 changes the output power of the generator 42 gradually, thereby preventing sudden changes in engine noise and providing a sense of security to the occupants.

In addition, the GCU 45 suppresses overshoot in the output power of the generator 42, which occurs due to a delay in response between controlling the operating state of the engine 41 and the change in the output power of the generator 42, thereby reducing fluctuations in the operating state of the engine 41.

Note that while Figure 5 illustrates an example in which the output power of the generator 42 is lower than the target power, the GCU 45 gradually changes the output power of the generator 42 even when the output power of the generator 42 is higher than the target power.

As shown in Figure 6, when the target power is changed, the GCU 45 temporarily stops the engine 41 and then controls the operating state of the engine 41 so that the power output from the generator 42 becomes the target power.

For example, in the example shown in FIG. 6, when the power generation mode is switched from the automatic power generation mode to the manual power generation mode (time t1), and when the power generation mode is switched from the manual power generation mode to the automatic power generation mode (time t2), the GCU 45 temporarily stops the engine 41 and then controls the operating state of the engine 41 so that the output power of the generator 42 becomes the target power.

In this way, in this embodiment, when the target power is changed, for example, by switching the power generation mode, the GCU 45 temporarily stops the engine 41, which has the following effects:

In other words, the change in engine sound can inform the occupants that the target power output of the generator 42 has been changed or that the power generation mode has been switched. Also, by temporarily stopping the engine 41, engine operation can be restarted, reducing engine speed and engine load.

In this embodiment, an example has been described in which the engine 41 is temporarily stopped when the power generation mode is switched, but the engine 41 may also be stopped for a predetermined period of time when the power generation mode is switched. Furthermore, when the target power is changed, the GCU 45 may reduce the output of the engine 41 for a certain period of time (for example, to an idle operating state) to reduce engine noise, and then control the operating state of the engine 41 so that the output power of the generator 42 becomes the target power. In this case, shocks or the like do not occur when the engine 41 is restarted, improving the ride comfort for occupants.

In addition, in manual power generation mode, the GCU 45 prompts the user to request power generation by the generator 42 at two or more prompting levels depending on the SOC of the battery 30. For example, when the SOC of the battery 30 changes from greater than 15% to less than 15% but greater than 10%, the GCU 45 outputs a message such as "The battery charge is decreasing. Would you like to generate power?" as a first prompting level, using audio and/or visual means via the operation panel 70, car navigation device 80, etc., to lightly prompt the user to generate power.

Furthermore, when the SOC of the battery 30 changes from a state where it is greater than 10% to a state where it is less than 10% but greater than 5%, the GCU 45 outputs a message such as "Please generate electricity" as a second level of prompting to strongly urge the user to generate electricity by voice and/or image via the operation panel 70, car navigation device 80, etc.

Furthermore, when the SOC of the battery 30 drops from above 5% to below 5%, the GCU 45 outputs a message such as "Power generation will begin" via the operation panel 70, car navigation device 80, etc., via audio and/or image to prompt the user to begin power generation, as a third level of prompting, and switches the power generation mode from manual power generation mode to automatic power generation mode.

In this embodiment, an example has been described in which, in manual power generation mode, the GCU 45 prompts the generator 42 to generate power at a prompting level corresponding to the current SOC of the battery 30. However, the GCU 45 may also prompt the generator 42 to generate power at a prompting level corresponding to the SOC of the battery 30 estimated at the time the target point is reached.

In this case, the GCU 45 prompts the generator 42 to generate electricity, taking into account the route conditions from the current position to the destination point obtained from the car navigation device 80. The route conditions from the current position to the destination point include distance, gradient, road surface conditions (e.g., asphalt, gravel, etc.), whether it is a public road or expressway, weather (weather, temperature, wind speed, etc.), time of day, etc.

For example, if it is estimated that the destination will be reached in the evening, the use of lights is predicted, and the GCU 45 will prompt the generator 42 to generate electricity, taking into account the amount of power consumed by the lights.

Furthermore, for example, if the air temperature is determined to be low or high, use of the air conditioner is predicted, and the GCU 45 takes into account the amount of power consumed by the air conditioner and prompts the generator 42 to request power generation.

Next, the operation of the GCU 45 in this embodiment will be described with reference to Figure 7. The operation of the GCU 45 shown in Figure 7 is repeatedly executed at predetermined intervals.

As shown in FIG. 7, the GCU 45 determines whether the power supply to the vehicle 10 is off (step S11). If the GCU 45 determines in step S11 that the power supply to the vehicle 10 is off, it determines whether the power generation switch 74 is on (step S12).

If the GCU 45 determines in step S12 that the power generation switch 74 is not on, it stops the engine 41 (step S23) and ends the current operation. If the GCU 45 determines in step S12 that the power generation switch 74 is on, it generates power in manual power generation mode (step S20) and ends the current operation.

If the GCU 45 determines in step S11 that the power supply to the vehicle 10 is not off, i.e., that the power supply to the vehicle 10 is on, it determines whether the power generation mode is the automatic power generation mode (step S13).

If the GCU 45 determines in step S13 that the power generation mode is not the automatic power generation mode, it determines whether the power generation switch 74 is on (step S15). If the GCU 45 determines in step S15 that the power generation switch 74 is not on, and if the engine 41 was running up until then, it stops the engine 41 regardless of the SOC value of the battery 30 (step S21), and ends the current operation. Note that if the engine 41 is not running at the time of step S15, the engine 41 remains stopped in step S21.

If the GCU 45 determines in step S15 that the power generation switch 74 is on, it generates power in manual power generation mode (step S17) and proceeds to processing in step S18.

If the GCU 45 determines in step S13 that the power generation mode is the automatic power generation mode, it determines whether the SOC of the battery 30 is equal to or lower than the lower limit SOC (step S14). The lower limit SOC is an SOC that has fallen to a level that may interfere with the driving of the vehicle 10, and is an SOC that has fallen to a level (e.g., SOC = 5%) that prevents the MG 20 from outputting a driving force commensurate with the driver's accelerator pedal operation.

If the GCU 45 determines in step S14 that the SOC of the battery 30 is not below the lower limit SOC, it terminates the current operation. If the GCU 45 determines in step S14 that the SOC of the battery 30 is below the lower limit SOC, it generates power in automatic power generation mode (step S16) and proceeds to processing in step S18.

In automatic power generation mode, power generation may be performed with a predetermined target power generation amount (e.g., upper limit SOC, emergency SOC, etc.), or power generation may be performed until the power generation end condition set in manual power generation mode is met.

In step S18, the GCU 45 determines whether the power generation mode was switched during power generation in the automatic power generation mode or the manual power generation mode. If the GCU 45 determines in step S18 that the power generation mode was not switched during power generation in the automatic power generation mode or the manual power generation mode, it ends the current operation without performing the processing of step S19.

If the GCU 45 determines in step S18 that the power generation mode has been switched while power is being generated in the automatic power generation mode or the manual power generation mode, it stops the engine 41 (step S19), sets the target power (step S22), and then ends the current operation.

In step S22, for example, the target power at the destination of the power generation mode change is set. For example, when the power generation mode is changed from automatic to manual, the target value of the output power selected by the occupant in manual power generation mode is set as the target power. When the power generation mode is changed from manual to automatic, a predetermined output power is set as the target power. Note that when the power generation mode is changed from manual to automatic, the target value of the output power selected in manual power generation mode may be set as the target power.

Next, with reference to Figure 8, the output power gradual change process executed by the GCU 45 in this embodiment will be described. The output power gradual change process shown in Figure 8 is repeatedly executed at predetermined intervals.

The output power gradual change process shown in Figure 8 is a process that changes the output power of the generator 42 so that it gradually approaches the target power when the current output power and target power do not match, such as when the power generation mode is switched. When the power generation mode is switched, the engine 41 is temporarily stopped as shown in Figure 6, so after the power generation mode is switched, the current output power and target power do not match. Therefore, in such cases, the output power gradual change process gradually changes the output power (= 0 kW) after the power generation mode is switched to approach the target power.

As shown in FIG. 8, the GCU 45 determines whether the target power and the current output power match (step S31). If the GCU 45 determines in step S31 that the target power and the current output power match, it terminates this output power gradual change process.

If the GCU 45 determines in step S31 that the target power and the current output power do not match, it determines whether the target power is greater than the current output power (step S32).

If the GCU 45 determines in step S32 that the target power is greater than the current output power, it determines whether the value obtained by subtracting the current output power from the target power is greater than 1.0 (kW) (step S33).

If the GCU 45 determines in step S33 that the value obtained by subtracting the current output power from the target power is greater than 1.0 (kW), it adds 1.0 (kW) to the current output power, sets this value as the temporary target power for the generator 42 (step S34), and proceeds to step S36.

If the GCU 45 determines in step S33 that the value obtained by subtracting the current output power from the target power is not greater than 1.0 (kW), i.e., is equal to or less than 1.0 (kW), it sets the target power as the temporary target power of the generator 42 (step S35) and proceeds to step S36.

In step S36, the GCU 45 linearly changes the output power of the generator 42 toward the temporary target power over the course of one second. After that, when the output power of the generator 42 reaches the temporary target power, the GCU 45 maintains the output power of the generator 42 at the temporary target power for one second (step S37), and then terminates this gradual output power change process.

If the GCU 45 determines in step S32 that the target power is not greater than the current output power, i.e., that the target power is equal to or less than the current output power, it determines whether the value obtained by subtracting the current output power from the target power is less than "-1.0 (kW)" (step S43). The GCU 45 may also determine whether the absolute value of the value obtained by subtracting the current output power from the target power is greater than "1.0 (kW)".

If the GCU 45 determines in step S43 that the value obtained by subtracting the current output power from the target power is less than "-1.0 (kW)", it sets the value obtained by subtracting 1.0 (kW) from the current output power as the temporary target power for the generator 42 (step S44) and proceeds to step S46.

If the GCU 45 determines in step S43 that the value obtained by subtracting the current output power from the target power is not less than "-1.0 (kW)," i.e., is equal to or greater than "-1.0 (kW)," it sets the target power as the temporary target power of the generator 42 (step S45) and proceeds to step S46.

In step S46, the GCU 45 linearly changes the output power of the generator 42 toward the temporary target power over the course of one second. After that, when the output power of the generator 42 reaches the temporary target power, the GCU 45 maintains the output power of the generator 42 at the temporary target power for one second (step S47), and then terminates this gradual output power change process.

Next, the power generation stop process executed by the GCU 45 in this embodiment will be described with reference to Figure 9. The power generation stop process shown in Figure 9 is repeatedly executed at predetermined intervals during manual power generation mode.

In the power generation stop process shown in Figure 9, the values used for each power generation end condition (90%, 10 minutes, 10 km) are examples and are not limited to these. Note that if the power generation end condition set in manual power generation mode is used as the power generation end condition in automatic power generation mode, the power generation stop process shown in Figure 9 will be executed even in automatic power generation mode.

As shown in FIG. 9, the GCU 45 determines whether the power generation termination condition is the first condition (step S51). The first condition is a condition that is met when the SOC of the battery 30 reaches the target SOC.

If the GCU 45 determines in step S51 that the power generation termination condition is the first condition, it determines whether the SOC of the battery 30 is 90% or higher (step S52).

If the GCU 45 determines in step S52 that the SOC of the battery 30 is not 90% or higher, it returns to step S51. If the GCU 45 determines in step S52 that the SOC of the battery 30 is 90% or higher, it stops power generation by the generator 42 (step S53) and ends this power generation stop process.

If the GCU 45 determines in step S51 that the power generation termination condition is not the first condition, it determines whether the power generation termination condition is the second condition (step S54). The second condition is a condition that is met when the charging time reaches a set time.

If the GCU 45 determines in step S54 that the power generation termination condition is the second condition, it determines whether the charging time has exceeded 10 minutes (step S55).

If the GCU 45 determines in step S55 that the charging time has not exceeded 10 minutes, it returns to step S51. If the GCU 45 determines in step S55 that the charging time has exceeded 10 minutes, it stops power generation by the generator 42 (step S53) and terminates this power generation stop process.

If the GCU 45 determines in step S54 that the power generation termination condition is not the second condition, it determines whether the power generation termination condition is the third condition (step S56). The third condition is a condition that is met when the amount of power generated is sufficient for the vehicle 10 to travel a set distance.

If the GCU 45 determines in step S56 that the power generation termination condition is the third condition, it calculates the amount of power generation required to travel 10 km (the amount of power generation for traveling 10 km) from the past electricity consumption (step S57), and proceeds to step S58. The past electricity consumption can be, for example, the "number of kilometers traveled per kWh of output power (km/kWh)" calculated from the output power and number of kilometers traveled over the last 10 minutes.

In step S58, the GCU 45 determines whether the amount of power generated by the generator 42 exceeds the amount of power generated for traveling 10 km. If the GCU 45 determines in step S58 that the amount of power generated by the generator 42 does not exceed the amount of power generated for traveling 10 km, the process returns to step S51.

If the GCU 45 determines in step S58 that the amount of power generated by the generator 42 exceeds the amount of power generated for a 10 km drive, it stops power generation by the generator 42 (step S53) and terminates this power generation stop process.

If the GCU 45 determines in step S56 that the power generation termination condition is not the third condition, it determines that the power generation termination condition is the fourth condition, calculates the amount of power generation required to reach the destination based on the distance to the destination, the remaining driving distance, and the past electricity consumption (step S59), and proceeds to step S60.

The fourth condition is met when the amount of power generation required to reach the target point (destination) obtained from the car navigation device 80 is secured. The distance to the destination is the distance from the current position of the vehicle 10 to the target point (destination). The remaining driving distance is the distance that can be traveled with the current SOC of the battery 30, and is calculated based on past electricity consumption. The past electricity consumption is calculated in the same way as in step S57. The remaining driving distance is calculated, for example, by the car navigation device 80, and transmitted from the car navigation device 80 to the GCU 45 via the ECU 100.

In step S60, the GCU 45 determines whether the amount of power generated by the generator 42 exceeds the amount of power required to reach the destination. If the GCU 45 determines in step S60 that the amount of power generated by the generator 42 does not exceed the amount of power required to reach the destination, the process returns to step S51.

If the GCU 45 determines in step S60 that the amount of power generated by the generator 42 exceeds the amount of power required to reach the destination, it stops power generation by the generator 42 (step S53) and terminates this power generation stop process.

Next, with reference to Figure 10, the power generation prompting process executed by the GCU 45 in this embodiment will be described. The power generation prompting process shown in Figure 10 is executed repeatedly at predetermined intervals during manual power generation mode. Note that the messages output in this power generation prompting process are merely examples and are not intended to be limiting.

As shown in FIG. 10, the GCU 45 receives the remaining driving distance from the current location of the vehicle 10 to the destination from the car navigation device 80 via the ECU 100 (step S71). The GCU 45 determines whether the remaining driving distance received in step S71 is less than the distance from the current location to the destination (step S72).

If the GCU 45 determines in step S72 that the remaining driving distance received in step S71 is less than the distance from the current location to the destination, it outputs a message stating "You will not be able to reach your destination with the current remaining battery charge" by voice and/or image via the operation panel 70, car navigation device 80, etc. (step S73), and then proceeds to step S75.

If the GCU 45 determines in step S72 that the remaining driving distance received in step S71 is not less than the distance from the current location to the destination, i.e., is equal to or greater than the distance from the current location to the destination, it outputs a message stating "The remaining battery charge after arriving at the destination will be XX%" by voice and/or image via the operation panel 70, car navigation device 80, etc. (step S74), and proceeds to step S75.

In step S75, the GCU 45 determines whether the SOC of the battery 30 is greater than 10% and less than or equal to 15%. If the GCU 45 determines in step S75 that the SOC of the battery 30 is greater than 10% and not less than or equal to 15%, it outputs a message, "The battery charge is decreasing. Would you like to generate power?" by voice and/or image via the operation panel 70, car navigation device 80, etc. (step S76), and terminates the power generation prompting process.

If the GCU 45 determines in step S75 that the SOC of the battery 30 is greater than 10% and less than or equal to 15%, it determines whether the SOC of the battery 30 is greater than 5% and less than or equal to 10% (step S77). Note that the GCU 45 may make the determination in step S75 using the SOC value upon arrival at the destination, in addition to the current SOC value.

If the GCU 45 determines in step S77 that the SOC of the battery 30 is greater than 5% and less than or equal to 10%, it outputs the message "Please generate power" via audio and/or image via the operation panel 70, car navigation device 80, etc. (step S78), and terminates the power generation prompting process.

If the GCU 45 determines in step S77 that the SOC of the battery 30 is greater than 5% and not less than 10%, it determines whether the SOC of the battery 30 is less than 5% (step S79).

If the GCU 45 determines in step S79 that the SOC of the battery 30 is not 5% or less, it terminates the power generation prompting process. If the GCU 45 determines in step S79 that the SOC of the battery 30 is 5% or less, it outputs the message "Power generation will begin" by voice and/or image via the operation panel 70, car navigation device 80, etc. (step S80).

Then, the GCU 45 starts the engine 41 (step S81) and begins generating electricity using the generator 42 (step S82). This forcibly starts power generation even in manual power generation mode.

Next, the GCU 45 determines whether the SOC of the battery 30 is 10% or greater (step S83). The GCU 45 repeats the process of step S83 until the SOC of the battery 30 is 10% or greater.

If the GCU 45 determines in step S83 that the SOC of the battery 30 is 10% or higher, it stops power generation by the generator 42 (step S84), then stops the engine 41 (step S85), and terminates the power generation stimulation process.

As described above, the electric vehicle according to this embodiment is configured so that the generator unit 40, which integrates the engine 41, starter, generator 42, INV 43, fuel tank 44, and GCU 45, is detachable from the vehicle 10. Therefore, in the electric vehicle according to this embodiment, the generator unit 40 can be removed from the vehicle 10 as needed, allowing the generator 42 to be used as an independent generator. This makes it possible to supply power to other electrical equipment outside the vehicle, for example, and makes effective use of the generator 42.

In addition, the electric vehicle according to this embodiment has two power generation modes: an automatic power generation mode and a manual power generation mode. Therefore, for example, while the automatic power generation mode is primarily used, the driver can switch to the manual power generation mode as needed to generate power in accordance with their intentions. For example, if the driver wants to charge the battery 30 more at their discretion, or if they want to save gasoline and drive to a charging facility, they can switch to the manual power generation mode, thereby ensuring operation that respects the driver's judgment.

In addition, the electric vehicle according to this embodiment is equipped with an operation panel 70 that allows the occupant to set the power generation state in manual power generation mode, so that the occupant can control the power generation state to their intended state by operating the operation panel 70.

The electric vehicle according to this embodiment also allows the occupant to set the power generation state in manual power generation mode by having the occupant specify an index corresponding to the target power generation amount (e.g., SOC, charging time, driving distance, power generation amount required to reach the destination, etc.). This allows the electric vehicle according to this embodiment to present the power generation amount to the driver as a conceptual index, making it easier for the driver to recognize the power generation amount.

This allows the driver to easily select the amount of power generation they need. Furthermore, because the driver can quantitatively grasp the amount of power generation through the above indicators, they can select the amount of power generation that best suits their needs.

Furthermore, even when the generator unit 40 is removed from the vehicle 10 and used independently, using similar conceptual indicators makes it easier for the driver to respond to power generation, engine noise, power generation fuel efficiency, and urgency according to the situation of the power supply destination.

In addition, the electric vehicle according to this embodiment allows the occupant to set the power generation state in manual power generation mode by using the operation panel 70 to set the level of power to be output by the generator 42. As a result, for example, if the driver requests that the SOC of the battery 30 be urgently restored, the target value (emergency) with the highest output power can be set as a stepwise progression of the target output power value.

Also, for example, if the driver requests power generation with a good balance between fuel efficiency and noise, a medium target output power value (high speed) can be set as a stepwise change in the target output power value.

Furthermore, for example, if the operator requests that power generation be performed with an emphasis on low noise, the target output power value can be set to the lowest output power target value (power saving) as a stepwise scale of the target output power value.

Furthermore, in the electric vehicle according to this embodiment, when the SOC of the battery 30 falls below a limit value (e.g., 5%) in manual power generation mode, the power generation mode is changed to automatic power generation mode, so that the vehicle 10 will not run out of power and can be guaranteed to continue running.

Furthermore, in the electric vehicle according to this embodiment, if the target power is not being output from the generator 42, the operating state of the engine 41 is controlled by gradually changing the output power of the generator 42 so that the output power of the generator 42 becomes the target power.

This eliminates any sense of discomfort felt by occupants and users. For example, sudden changes in engine sound are suppressed, providing a sense of security to occupants. Furthermore, because the output power is gradually changed toward the target power while checking the engine state, excessively unstable operation of the engine 41 can be prevented. For example, fluctuations in the operating state of the engine 41, such as when the throttle opening is increased too much and then returned to its original position, can be suppressed.

Furthermore, since the electric vehicle according to this embodiment does not supply power directly from the generator unit 40 to the MG 20 but rather via the battery 30, a smooth transition in operation is preferable, without requiring sudden movement. Therefore, as described above, it is useful to gradually change the output power of the generator 42 and control the operating state of the engine 41 so that the output power of the generator 42 becomes the target power.

In addition, in the electric vehicle of this embodiment, during the period in which the output power of the generator 42 is gradually changed, the operating state of the engine 41 is controlled so that a first period T1 in which the output power changes toward the target power and a second period T2 in which the output power changes less than in the first period T1 are repeated consecutively.

In this way, by providing a relaxation period, such as the second period T2, where the change is gradual or no change occurs between consecutive first periods T1, it is possible to smooth out changes in the engine operating state during the period when the output power of the generator 42 is gradually changed. Changes in the engine operating state are adjusted using the throttle opening, injector injection amount, etc. In this case, providing an intermittent period to wait for a response rather than continuously changing the engine operating state allows for more accurate control when adjusting the throttle opening, injector injection amount, etc. Furthermore, by controlling the operating state of the engine 41 while checking the response of the exhaust gas control, it is possible to expect benefits such as avoiding unnecessary exhaust gas emissions when gradually changing the output power of the generator 42 and controlling the operating state of the engine 41 so that the output power of the generator 42 becomes the target power.

Furthermore, in manual power generation mode, the electric vehicle according to this embodiment prompts the driver to request power generation by the generator 42 at two or more prompting levels according to the SOC of the battery 30, thereby assisting the driver in making decisions about requesting power generation.

In this embodiment, an example of executing the process shown in Figure 10 as the power generation stimulation process has been described, but this is not limiting, and the power generation stimulation process shown in the following Figure 11 may also be executed.

With reference to Figure 11, a modified example of the power generation stimulation process executed by the GCU 45 of this embodiment will be described. The power generation stimulation process shown in Figure 11 is repeatedly executed at predetermined intervals during manual power generation mode.

As shown in FIG. 11, the GCU 45 determines whether there is a charging facility on the route to the destination set by the car navigation device 80 (step S101).

Specifically, the GCU 45 determines whether there is a charging facility on the route to the destination based on whether it has received information about charging facilities on the route to the destination from the car navigation device 80, i.e., whether it has detected a charging facility on the route to the destination. Note that the car navigation device 80 may search for multiple routes to the destination. In this case, for example, the GCU 45 may preferentially select a route that has charging facilities among the multiple routes.

If the GCU 45 determines in step S101 that there is no charging facility on the route to the destination, it determines whether it is possible to travel to the destination (step S105).

Specifically, if the remaining driving distance calculated from the current SOC of the battery 30 is longer than the distance from the current position to the destination, the GCU 45 can determine that it is possible to travel from the current position to the destination. If the remaining driving distance calculated from the current SOC of the battery 30 is shorter than the distance from the current position to the destination, the GCU 45 can determine that it is not possible to travel from the current position to the destination. As in this embodiment, the remaining driving distance is calculated in the car navigation device 80 and transmitted from the car navigation device 80 to the GCU 45 via the ECU 100.

If the GCU 45 determines in step S105 that it is possible to travel to the destination, it terminates the power generation stimulation process. If the GCU 45 determines in step S105 that it is not possible to travel to the destination, it performs power generation stimulation to encourage power generation by driving the engine 41 (step S106).

In step S106, the GCU 45 also prompts the occupant to adjust the power generation amount, informing them of the appropriate power generation amount based on the amount of power required to travel to the destination.

If the GCU 45 determines in step S101 that a charging facility is located on the route to the destination, it determines whether or not it is possible to travel to the charging facility (step S102).

If the GCU 45 determines in step S102 that it is possible to travel to a charging facility, it issues a charging prompt to urge the occupant to charge the battery 30 at the charging facility (step S103). At this time, if the engine 41 is already generating electricity, the GCU 45 issues a power generation stop prompt in step S103 to notify the occupant that power generation will be stopped. The method of the power generation stop prompt is the same as the method of the charging prompt and the power generation prompt. The GCU 45 terminates this power generation prompt processing after processing step S103.

If the GCU 45 determines in step S102 that it is not possible to travel to the charging facility, it performs a charging prompt and a power generation prompt (step S104). In step S104, the GCU 45 also performs a power generation adjustment prompt, which notifies the occupant of an appropriate power generation amount based on the amount of power required to travel to the charging facility. The GCU 45 terminates this power generation prompt process after processing step S104.

In the power generation prompting process shown in FIG. 11 , the GCU 45 preferably determines whether the vehicle 10 can travel from its current location to the destination or charging facility, for example, every predetermined time or every predetermined distance, after the vehicle 10 starts traveling. Even if the GCU 45 determines that the vehicle 10 can travel to the destination or charging facility without generating power when the vehicle 10 starts traveling, the vehicle 10 may not be able to travel to the destination or charging facility if subsequent traveling conditions change or the route to the destination or charging facility is changed to a route different from the originally set route. In such cases, by periodically determining whether the vehicle 10 can travel from its current location to the destination or charging facility as described above, the GCU 45 can prompt the occupant to charge the battery 30 when it determines that the vehicle 10 cannot travel to the destination or charging facility. This allows the GCU 45 to prompt the occupant to charge the battery 30 early.

According to this modification, if a charging facility is present on the route from the current location of the vehicle 10 to the destination, the occupant is prompted to charge at that charging facility, thereby preventing the occupant from unnecessarily driving the engine 41 to generate electricity even when charging at the charging facility is possible. Therefore, this modification can reduce fuel consumption by the engine 41.

In addition, this modified example notifies the driver whether or not power generation by driving the engine 41 is necessary, depending on the amount of power required to travel from the vehicle 10's current location to the charging facility. For example, if the vehicle 10 cannot travel from its current location to the charging facility due to insufficient SOC of the battery 30, a power generation prompt is issued to urge the occupant to drive the engine 41 and generate power using the generator 42. Therefore, this modified example can prevent the SOC of the battery 30 from decreasing to the point where the vehicle 10 is unable to travel. This prevents the vehicle 10 from coming to a standstill on the road due to insufficient SOC of the driving battery 30.

In addition, this modified example is configured so that when power is being generated by driving the engine 41, the occupant is prompted to generate the appropriate amount of power depending on whether or not there is a charging facility on the route from the current location of the vehicle 10 to the destination. As a result, this modified example can reduce fuel consumption by the engine 41 and prevent the battery 30 from running out of power, regardless of whether or not there is a charging facility on the route to the destination.

Furthermore, in this embodiment, the generator unit 40 is configured to be detachable from the vehicle 10, but the generator unit 40 may not be detachable from the vehicle 10 and may be pre-installed. In this case, the engine 41, starter, generator 42, INV 43, fuel tank 44, and GCU 45 do not need to be configured as an integrated unit.

While an embodiment of the present invention has been disclosed, it is clear that modifications may be made by those skilled in the art without departing from the scope of the present invention. For example, although the generator 42 and the starter, which is a device for starting the engine, are provided separately, the generator 42 may be a starter generator that functions as both a generator and a starter. All such modifications and equivalents are intended to be encompassed by the following claims.

10. Vehicles (electric vehicles)
14 Drawer rail 20 MG (motor)
21 INV
30 Battery 31 Battery sensor 40 Generator unit 41 Engine (internal combustion engine)
42 Generator 43 INV
44 Fuel tank 45 GCU (control unit)
70 Operation panel (power generation status setting section)
71 remaining fuel amount display area 72 generated power display area 73 SOC display area 74 power generation switch 75a, 75b power generation control switch 76 power generation control status display area 77 setting switch 80 car navigation device 88a, 88b, 88c, 88d selection buttons 89a, 89b, 89c, 89d switch 100 ECU
101 CAN communication line T1 First period T2 Second period

Claims (2)

A power generation control device for an electric vehicle including a driving motor, a battery that supplies power to the motor, a generator that generates power to charge the battery, and an internal combustion engine that drives the generator,
a control unit that controls the operating state of the internal combustion engine in either an automatic power generation mode that controls the operating state of the internal combustion engine in accordance with the remaining capacity of the battery, or a manual power generation mode that starts operation of the internal combustion engine in accordance with an operation that requests power generation by the generator;
a power generation state setting unit that allows a passenger to set a power generation state in the manual power generation mode;
the generator, the internal combustion engine, the control unit, and the power generation state setting unit are integrated into a generator unit that is detachable from the electric vehicle and that can be removed from the electric vehicle and used as a standalone power generation device that supplies electric power to an electric device other than an electric device provided on the electric vehicle,
the power generation state setting unit is configured so that the power generation state in the manual power generation mode can be set by the occupant by specifying one or more of SOC , charging time, mileage, and power generation amount required to reach the destination as an index corresponding to a target power generation amount;
The power generation control device is characterized in that the power generation state setting unit is configured so that the power generation state in the manual power generation mode can be set by the occupant by gradually setting a target value for the output power to be output by the generator. The power generation control device described in claim 1, characterized in that the control unit changes the power generation mode to the automatic power generation mode when the remaining capacity of the battery falls below a limit value in the manual power generation mode.