WO2017034051A1 - System and method for controlling wind farm composed of various wind turbines - Google Patents

Abstract

A system and a method for controlling a wind farm composed of various wind turbines are provided. According to one embodiment of the present invention, the method for controlling a wind farm comprises: allocating active power, to be outputted from wind turbines, by adding up/referring to the loss of wind turbine units; allocating reactive power, to be outputted from the wind turbines, by adding up/referring to the loss of wind turbine array units; and controlling the wind turbines according to the allocation results. Therefore, since a wind farm composed of various wind turbines can be optimally controlled, ultimately, generation efficiency is maximized and maintenance costs can be minimized.

Description

Wind farm control system and method consisting of multiple wind turbines

The present invention relates to a wind farm control technology, and more particularly, to a system and method for controlling a wind farm consisting of multiple wind turbines.

A wind farm is a place where many wind turbines are installed to obtain energy from natural wind on land or at sea. It is widely researched / utilized in Germany, USA, Denmark, etc. all over the world, and there are small wind farms in our country.

Wind farms must not only produce and provide the power required by the grid operator, but also operate to meet grid linkage criteria, and it is important to maximize the amount of power produced by the grid operator.

Furthermore, it is also necessary to minimize the energy load reduction of the power plant to minimize energy production costs and reduce maintenance costs.

At present, the wind turbines constituting the wind farm are composed of various types. Therefore, the search for an optimal control method of a wind farm composed of multiple wind turbines is required.

The present invention has been made to solve the above problems, an object of the present invention is to provide a wind farm control system and method consisting of multiple wind turbines.

According to one embodiment of the present invention, a wind farm control method includes: a first allocation step of allocating effective powers to be output from wind turbines constituting a wind farm; A second allocating step of allocating reactive powers to be output from the wind turbines; And controlling the wind turbines in accordance with assigned active powers and reactive powers, wherein the first allocation step refers to summing losses in wind turbine units to allocate the active powers, and The second allocating step refers to summing losses in wind turbine array units and allocating the reactive powers.

The wind turbines may include heterogeneous wind turbines and may be modeled as heterogeneous wind turbines.

The wind turbine model may be a model that outputs at least one of wind, active power command, and reactive power command, and outputs at least one of active power, reactive power, thrust factor, rotor speed, generator torque, pitch, and thrust. Can be.

The first allocating step includes the active power such that the sum of the active powers output from the wind turbines satisfies the total active power output from the wind farm, and the sum of the loads in the wind turbines is minimized. Can be assigned.

Further, the second allocating step may allocate the reactive powers such that the sum of the loss coefficients due to the reactive power in the wind turbine arrays is minimum.

And, the control step, it is possible to control each wind turbine to generate power according to the assigned active powers and reactive powers at a time corresponding to the position of each wind turbine.

Further, the control step, the distance between the point where the measurement of the wind incident on the wind farm is performed and the position of the target wind turbine, the measured wind speed, the wind speed of the wind at the position of the target wind turbine and the wind Using the measurement time point of, the time point at which the measured wind reaches the position of each wind turbine can be calculated.

On the other hand, the wind farm control system according to another embodiment of the present invention, the processing unit for allocating the active power and the reactive power to be output from the wind turbines constituting the wind farm; And a communication unit configured to transmit a control command of the wind turbines to the wind turbines according to allocated active powers and reactive powers, wherein the processing unit allocates the active powers by summing a loss in a wind turbine unit. Reference is made to reference, and the losses in the wind turbine array unit are added to allocate the reactive powers.

According to various embodiments of the present invention, it is possible to optimally control a wind farm composed of multiple wind turbines, ultimately maximizing power generation efficiency and minimizing maintenance costs.

1 is a view showing a wind farm control system according to an embodiment of the present invention,

2 is a detailed view of a wind turbine model;

3 to 6 is a flow chart provided in the description of the wind farm control method according to another embodiment of the present invention,

7 is a view provided for further explanation of the reduction factor calculation;

8 to 10 are views provided for further explanation of the wind turbine control process by the synchronization process;

11 is a view showing the wind turbine and wind turbine array arrangement in the wind farm, and,

12 and 13 are diagrams illustrating the state and the output screen of the wind turbines.

Hereinafter, with reference to the drawings will be described the present invention in more detail.

1 is a view showing a wind farm control system according to an embodiment of the present invention. In order to be suitable for real-time control, the wind farm control system according to the embodiment of the present invention is implemented with a real-time object framework.

Wind farm control system according to an embodiment of the present invention, as shown in Figure 1, the CDM Manager (Common Data Model Manager) 121, Parallel Processing Manager (122), Communication Manager (Communication Manager) 123 and a data logging manager 124.

The CDM manager 121 has various wind turbine models and provides wind turbine models installed in the wind farm. In addition, the CDM manager 121 may generate a new wind turbine model based on parameters set by the manager. This is for the case that you do not have the wind turbine model.

The parallel processing manager 122 generates wind fields of the wind farm, predicts the state and output of the wind turbines based on the generated wind fields, and controls the wind turbines based on the prediction result.

The communication manager 123 communicates with the wind turbines to deliver control commands. In addition, the communication manager 123 is a module that manages data communication with an external server and a DB. The communication manager 123 may receive a model and parameters necessary for controlling the wind farm from the outside and transmit the control result to the outside.

2 is a view showing in detail the wind turbine model (Wind Turbine Model). The wind turbine model is a model that simulates a real wind turbine. The wind turbine model is configured to generate inputs and outputs in units of 10ms, which is very similar to a real wind turbine. In addition, the wind turbine model is separately provided according to the manufacturer, model and specifications.

As illustrated in FIG. 2, the wind turbine model receives wind, an active power command p_cmd, and a reactive power command q_cmd.

Here, the wind (wind) is a parameter for the wind incident to the wind turbine, the active power command (p_cmd) represents the active power to be output (produced) from the wind turbine, the reactive power command (q_cmd) is a wind turbine Indicates reactive power to be output (produced).

In addition, as shown in FIG. 2, the wind turbine model includes active power (p_out), reactive power (q-out), thrust factor (Ct), rotor speed (rot_spd), generator torque (gen_torq), and pitch (pitch). And thth as outputs.

Hereinafter, a process of controlling the wind farm by the system shown in FIG. 1 will be described in detail with reference to FIG. 3. 3 is a flowchart provided to explain a wind farm control method according to another embodiment of the present invention.

As shown in FIG. 3, first, the parallel process manager 122 initializes programs necessary for wind farm control (S210), and measures wind conditions of wind incident on the wind farm (S220). Wind measurements are made via Met Mast (not shown) in wind farms.

Next, the parallel process manager 122 allocates active powers to be output to the wind turbines based on the wind condition information measured in step S220 (S230). A detailed process of step S230 is shown in FIG.

In order to allocate the total active power to be output from the wind farm to each of the wind turbines, the parallel processing manager 122 first initializes the corresponding algorithm (S310) and calls the objective function (S320). The routine of the objective function is shown in FIG.

As shown in FIG. 5, through the objective function, the parallel processing manager 122 calculates the wake from the wind measured in step S220 of FIG. 3 to generate a wind field of the wind farm (S510).

In the wake calculation, a reduction factor indicating the degree of the wind decrease by the at least one wind turbine disposed in front is calculated, and the reduction factor is applied to the measured wind speed to calculate the wind speed of the wind incident on the wind turbines.

For example, if there are N wind turbines placed in front of a particular wind turbine, N reduction coefficients by each of the wind turbines placed in front are calculated, and the N reduction coefficients are summed (or multiplied) for that wind turbine. The reduction factor is calculated.

A process of obtaining the reduction factor will be described in more detail with reference to FIG. 7. 7 is a view provided for explaining the process of calculating the reduction coefficient according to the wake. In FIG. 7, the wind farm in which the wind turbine-1 710, the wind turbine-2 720, and the wind turbine-3 730 are arrange | positioned was assumed.

As shown in FIG. 7, the rear region is a region in which the wind is reduced by the wake, that is, the region to which the reduction factor is to be applied, based on the points where the wind turbines are disposed. In FIG. 7, the reduction coefficient by the wind turbine-1 710 is a1, the reduction coefficient by the wind turbine-2 720 is a2, and the reduction coefficient by the wind turbine-3 730 is a3. therefore,

1) Since the area-1 701 is an area affected only by the wake of the wind turbine-1 710, the reduction factor of the area-1 701 is a1,

2) Zone-2 702 is an area affected only by the wake of wind turbine-2720, so the reduction factor of zone-2 702 is a2,

3) Since the area-3 703 is an area that is simultaneously affected by the wakes of the wind turbine-1 710 and the wind turbine-2 720, the reduction factor of the area-3 703 is a1 + a2 (or, a1 * a2),

4) Since area-4 704 is an area affected simultaneously by the downstream of wind turbine-1 710 and wind turbine-3 730, the reduction factor of area-4 704 is a1 + a3 (or, a1 * a3),

5) Since the area-5 705 is an area affected simultaneously by the downstream of the wind turbine-2 720 and the wind turbine-3 730, the reduction factor of the area-5 705 is a2 + a3 (or, a2 * a3),

6) Zone-6 706 is an area that is simultaneously affected by the wakes of wind turbine-1 710, wind turbine-2 720 and wind turbine-3 730, thus reducing zone-6 706. The coefficient is a1 + a2 + a3 (or a1 * a2 * a3).

According to this method, since the wind turbine-2 720 is disposed in the area-1, the reduction factor is a1. And since the wind turbine-3 730 is arrange | positioned at the area-3, a reduction coefficient becomes a1 + a2 (or a1 * a2).

In this way, the parallel processing manager 122 can calculate the wind speed of the wind to be incident on the wind turbines by calculating the reduction coefficient and applying the reduction coefficient to the measured wind speed.

By this process, the wind condition of the wind incident on the respective wind turbines is determined. The parallel process manager 122 calculates the thrust of the wind turbines based on this to calculate the output expected effective power (S520), and calculates the cost functions of the wind turbines (S530).

Here, the expected load represents the mechanical load of the wind turbine generated by outputting the expected active power calculated in step S520. Meanwhile, steps S520 and S530 are performed in parallel with each of the wind turbines. To shorten the computation time.

It returns to FIG. 4 and demonstrates. The parallel process manager 122 determines whether optimal allocation is made in allocating effective powers to be output for each of the wind turbines based on the results in the steps S520 and S530 of FIG. 6 (S340). If not optimal allocation (S340-N), the parallel processing manager 122 performs again from step S320.

On the other hand, it is possible to limit the number of repetitions. This number limit can be determined based on the reduction factors by the wake of the wind turbines. Specifically, it is determined that the number of repeatable times is inversely proportional to the minimum value of the reduction coefficients.

For example, if the minimum reduction factor is 0.9, the maximum number of repetitions is limited to 30. If the minimum reduction factor is 0.8, the maximum number of repetitions is limited to 40. If the minimum reduction factor is 0.7, the maximum number of repetitions is limited to 50. It is.

The smaller the minimum reduction factor is, the more difficult it is to assign optimally, so that the number of repeatable times is set higher.

The optimal allocation is based on the active powers assigned to each of the wind turbines and the loads thereof, so that the sum of the loads is minimal when the sum of the wind turbines active powers is equal to the active power to be output at the wind farm. It is.

In other words, the optimal allocation is such that the sum of the loads placed on the wind turbines is minimal. The load to be applied to the wind turbine can be calculated by substituting the cost function for the wind condition to be input to the wind turbine and the effective power to be output.

5, the output ratio of the wind turbines is determined such that the sum of the loads of the wind turbines is minimized.

For example, if [wind turbine-1, 2, 3, 4] produces [40kW, 30kW, 20kW, 10kW] respectively, the total mechanical load is 100kJ, whereas [30kW, 30kW, 20kW, 20kW] is produced. If the total mechanical load is 90 kJ, the power generation requirements for the wind turbines are determined to be [30 kW, 30 kW, 20 kW, 20 kW].

On the other hand, when [wind turbine-1, 2, 3, 4] produces [30kW, 20kW, 30kW, 20kW] respectively, if the total mechanical load is 85kJ, the power generation requirements for wind turbines are [30kW, 20kW, 30kW]. , 20 kW].

Again, the description will return to FIG. 3. When the effective power allocation is completed to the wind turbines by the step S230, the parallel processing manager 122 allocates reactive power to the wind turbines (S240). A detailed process of step S240 is shown in FIG. 6.

As shown in FIG. 6, first, the parallel processing manager 122 calculates expected reactive power of wind turbines (S410), and calculates a loss factor due to reactive power in units of wind turbine arrays (S420).

11 is a view showing an arrangement of wind turbines in a wind farm. As shown in FIG. 11, the wind turbines are cabled, with the cabled wind turbines making up the wind turbine array. As shown in FIG. 11, seven wind turbine arrays are formed in a wind farm.

Thereafter, the parallel processing manager 122 allocates reactive powers for the wind turbines (S430). The reactive power allocation in step S430 is performed by adjusting the reactive powers of the wind turbines such that the sum of the loss coefficients of the wind turbine arrays is minimum.

It should be noted that the reactive power allocation is in wind turbine units and the loss factor calculation is in wind turbine array units. When the step S430 is completed, the reactive power to be allocated for the wind turbines are determined (S440).

Again, the description will return to FIG. 3. When the effective power and the effective power allocation to the wind turbines are determined by the steps S230 and S340 (S250), the parallel processing manager 122 performs a synchronization process at each time point corresponding to the position of each wind turbine. The wind turbine controls to generate power according to the assigned active / reactive power (S260).

Since the timings at which the effective / reactive power required for the wind turbines should be applied depend on the position of the wind turbine, the parallel processing manager 122 assigns each wind turbine at a time corresponding to the position of each wind turbine. It is controlled to generate power according to the active and reactive power.

Specifically, the parallel processing manager 122 calculates the point in time when the measured wind reaches the position of each wind turbine. At this time, the parallel processing manager 122 measures the distance using the distance between the point where the measurement is performed and the position of the target wind turbine, the measured wind speed, the wind speed at the position of the target wind turbine, and the measurement time point of the wind. The time when the wind reaches the position of each wind turbine is calculated. In addition, the parallel process manager 122 controls each wind turbine to generate power according to the effective / reactive power for each wind turbine at the time point calculated for each.

A method of calculating a time point corresponding to the position of the wind turbine will be described in more detail with reference to FIGS. 8 to 10. 8 is a view provided to explain a method of calculating a time point corresponding to a position of a wind turbine.

8, wind turbine-1 (WT (1)) 810, wind turbine-2 (WT (2)) 820, and wind turbine-3 (WT (3)) 830 are shown. The distance between the wind turbine-1 810 and the wind turbine-2 820 is 5D (= 500 m), and the distance between the wind turbine-2 820 and the wind turbine-3 830 is 6D (= 600 m).

In such a situation, if the initial wind (u) incident on the wind turbine-1 (810) is 10 m / s, and the wind (u ') incident on the wind turbine-2 (820) is 9 m / s, the wind turbine- The time it takes for wind from 1 (810) to wind turbine-2 (820) is 500 / ((u + u ') / 2) = 52.632 seconds. Therefore, wind, such as wind incident to wind turbine-1 810, is incident to wind turbine-2 820 after about 52 seconds. Therefore, the time to apply the active / reactive power allocated to the wind turbine-2 (820) is about 52 seconds slower than the time to apply the active / reactive power allocated to the wind turbine-1 (810).

Accordingly, as shown in FIG. 9, the propagation time is recorded in the control table of the wind turbine-2 820, and the parallel processing manager 122 allocates the effective / reactive power allocated at the time of adding the propagation time to the input time. Will be applied.

FIG. 10 is a diagram illustrating an example of a control table for each wind turbine at a specific time point. As shown in FIG. 10, the parallel processing manager 122 manages a table for application predicted wind speed and demand generation amount for each wind turbine at each time point. FIG. 10 shows a wind turbine-specific control table at t + 52.632 seconds, and at t + 52.632 seconds, the wind turbine-2 820 WT 2 has a predicted wind speed of 9 m / s and a required generation amount. It can be seen that it is 4MW.

Through this process, the parallel processing manager 122 can control each wind turbine to generate power according to the required power generation amount calculated for each wind turbine at a time corresponding to the position of each wind turbine. Accordingly, the parallel processing manager 122 can synchronize the plurality of wind turbines to an appropriate time point and allocate the required power generation amount to each.

Thereafter, the parallel processing manager 122 repeats the steps S220 to S260 for the next wind to be incident to the wind farm (S270), so that the wind farm control is made in real time.

In this process, the parallel processing manager 122 may provide information, either graphically or in data, about the status and output of the wind turbines, as shown in FIG. 12 or FIG. 13.

On the other hand, the technical idea of the present invention can be applied to a computer-readable recording medium containing a computer program for performing the functions of the apparatus and method according to the present embodiment. In addition, the technical idea according to various embodiments of the present disclosure may be implemented in the form of computer readable codes recorded on a computer readable recording medium. The computer-readable recording medium can be any data storage device that can be read by a computer and can store data. For example, the computer-readable recording medium may be a ROM, a RAM, a CD-ROM, a magnetic tape, a floppy disk, an optical disk, a hard disk drive, or the like. In addition, the computer-readable code or program stored in the computer-readable recording medium may be transmitted through a network connected between the computers.

In addition, although the preferred embodiment of the present invention has been shown and described above, the present invention is not limited to the specific embodiments described above, but the technical field to which the invention belongs without departing from the spirit of the invention claimed in the claims. Of course, various modifications can be made by those skilled in the art, and these modifications should not be individually understood from the technical spirit or the prospect of the present invention.

Claims (8)

A first allocating step of allocating effective powers to be output from the wind turbines constituting the wind farm; A second allocating step of allocating reactive powers to be output from the wind turbines; And Controlling the wind turbines in accordance with assigned real powers and reactive powers; The first allocation step, Refer to the allocation of the effective powers, summing the losses in wind turbine units, The second allocation step, A method for controlling a wind farm, comprising summing up losses in a wind turbine array unit and allocating the reactive powers. The method according to claim 1, The wind turbines, A wind farm control method comprising heterogeneous wind turbines, modeled as a heterogeneous wind turbine. The method according to claim 2, Wind turbine model, At least one of the wind, active power command, reactive power command as an input, A wind farm control method, characterized in that the model outputs at least one of active power, reactive power, thrust factor, rotor speed, generator torque, pitch, and thrust. The method according to claim 1, The first allocation step, Wherein the sum of the active powers to be output from the wind turbines satisfies the total active power to be output from the wind farm, while allocating the active powers such that the sum of the loads in the wind turbines is minimal. Control method. The method according to claim 1, The second allocation step, And assigning the reactive powers such that the sum of the loss coefficients due to the reactive power in the wind turbine arrays is minimum. The method according to claim 1, The control step, At a time corresponding to the position of each wind turbine, controlling each wind turbine to generate power in accordance with assigned active and reactive powers. The method according to claim 6, The control step, Using the distance between the point where the measurement of the wind incident on the wind farm is performed and the position of the target wind turbine, the measured wind speed, the wind speed at the position of the target wind turbine, and the measurement time point of the wind, And calculating a time point at which the measured wind reaches the position of each wind turbine. A processing unit for allocating active powers and reactive powers to be output from wind turbines constituting the wind farm; And a communication unit which transmits a control command of the wind turbines to the wind turbines according to the assigned real powers and reactive powers. The processing unit, Refer to the allocation of the effective powers, summing the losses in wind turbine units, A wind farm control system, characterized by summing up losses in a wind turbine array unit and allocating the reactive powers.

Images