A wind farm wake control system based on external controller

Abstract

The present invention provides a wind farm wake control system, comprising: an external controller and a sector control management subsystem, wherein the external controller is used to receive a wake control instruction from the sector control management subsystem and enter the following active yaw process: obtaining wind condition information of the current wind turbine; traversing and comparing the wind condition information of the current wind turbine with the pre-stored yaw angle correction table information to obtain the optimal yaw angle adapted to the wind condition of the current wind turbine; calculating the target wind direction input value according to the optimal yaw angle and the wind direction angle of the current wind turbine and sending it to the original controller, so that the original controller performs an active yaw action according to the target wind direction input value. The yaw angle correction calculation is completed by adding an external controller to replace the original controller, and the calculated adjustment value is sent to the original controller, so that the original controller performs an active yaw action according to the adjustment value, thereby improving the influence of the wake on the wind turbine and increasing the power generation.

Description

Technical Field

[0001] The present invention relates to the technical field of wind farms, and in particular to a wind farm wake control system based on an external controller and an implementation method thereof. Background Art

[0002] As an important factor affecting the economic benefits of wind farms, the wake effect can easily cause the wind speed in the wake area to decrease and the turbulence to increase, leading to power loss and fatigue load increase of downstream wind turbines, resulting in vibration and mechanical damage of the units. Optimizing the yaw angle of the units in the wind farm and changing the spatial and speed distribution of the wind blowing to the rear row of units can achieve a certain degree of wake improvement.

[0003] Under different inflow wind directions, the front-row units in the wind farm may have a wake effect on the rear-row units, and in specific wind direction scenarios, the wake of the front-row units will still reach the downstream units when it fails to fully diffuse, affecting the load characteristics and causing power generation losses in the rear-row units. Actively changing the yaw angle of each unit is an important way to reduce the wake effect. my country currently lacks active yaw control for large wind farms, and the unit control strategy is relatively simple. Therefore, it is necessary to complete the manual correction of the wind direction signal according to the offline yaw angle optimization table before the wind direction signal enters the main controller, so that the unit can actively yaw, capture more wind energy under the influence of the wake, and increase the power generation of the entire wind farm. Summary of the invention

[0004] The purpose of the present invention is to provide a wind farm wake control system based on an external controller. The system can complete the yaw angle correction calculation by adding an external controller to replace the original controller without changing the operation logic of the original controller of the wind turbine set, and send the calculated target wind direction input value to the original controller, so that the original controller performs active yaw action according to the target wind direction input value, thereby improving the influence of the wake on the wind turbine set.

[0005] In order to achieve the above object, the present invention provides a wind farm wake control system, the system comprising:

[0006] The external controller and the sector control management subsystem are two parts; wherein the external controller is set in the wind turbine and is connected to the station sector control management subsystem and the original controller of the current wind turbine respectively, and is used to receive the wake control instruction of the sector control management subsystem and enter the active yaw process, and the active yaw process includes:

[0007] Obtain the current wind condition information of the wind turbine;

[0008] The wind condition information of the current wind turbine generator set is compared with the pre-stored yaw angle correction table information, the group corresponding to the wind condition information is determined, and the optimal yaw angle adapted to the wind condition of the current wind turbine generator set is obtained;

[0009] Calculating a target wind direction input value according to the optimal yaw angle and the wind direction angle currently received by the wind turbine generator set; and

[0010] The target wind direction input value is sent to the original controller, so that the original controller performs an active yaw action according to the target wind direction input value.

[0011] Optionally, the external controller is also connected to a wind speed and wind direction measuring device of the current wind turbine generator set, and obtaining the wind condition of the current wind turbine generator set includes receiving the wind speed and wind direction provided by the wind speed and wind direction measuring device.

[0012] Optionally, the wind speed and wind direction include wind speed and wind direction information detected by two anemometers, and the two anemometers include: an ultrasonic anemometer and a mechanical anemometer.

[0013] Optionally, the wind direction information detected by the two anemometers includes wind direction A and wind direction B;

[0014] Among them, the wind direction A and wind direction B are both the actual measured wind directions of the current wind turbine and participate in the correction calculation to obtain the corresponding target wind direction input value A1 and target wind direction input value B1; the target wind direction input value A1 participates in the execution of the yaw action process in the main controller, and the target wind direction input value B1 is only used for comparison with A1.

[0015] Optionally, the external controller is also used to send the wind condition information of the current wind turbine to the site sector control and management subsystem.

[0016] Optionally, the external controller is further used to exit the active yaw process according to the wake control exit instruction sent by the station sector control management subsystem, and perform the following operations when exiting the active yaw process:

[0017] The wind condition currently being experienced by the wind turbine generator set is acquired, and the wind condition currently being experienced by the wind turbine generator set is forwarded to an original controller of the current wind turbine generator set.

[0018] The wind farm wake control system provided by the present invention includes the station sector control management subsystem, which is used to perform the following operations:

[0019] Obtain wind condition information of corresponding wind turbine generator sets sent by each external controller;

[0020] According to the wind condition information, determine whether the wind direction at the corresponding wind turbine location is in a stable state, and the current average wind direction D n Whether it is located within the sector management wind direction setting area Ω, and sending the wake control instruction to the external controller.

[0021] Optionally, based on the average downwind direction values ​​D1, D2, ..., D in time period t1 n , calculate the difference between the average values ​​ΔD and the reference difference D ref If ΔD<D ref , it indicates that the wind direction of the unit is in a stable state during time period t1;

[0022] Where, ΔD=|D n -D n-1 |+…+|D2-D1|.

[0023] Optionally, before the sector control management subsystem sends the wake control instruction to the external controller, the method further includes determining a current average wind direction D in a stable state. n Whether it is located within the sector management wind direction setting area Ω, if so, sending a wake control start instruction to the external controller;

[0024] The sector management wind direction setting area Ω is the wind direction area where the unit is affected by the wake.

[0025] Optionally, the station sector control management subsystem is further configured to calculate the current wind direction average value D n When the wind direction does not fall within the sector management wind direction setting area Ω, a wake control exit instruction is sent to the external controller.

[0026] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present invention but do not constitute a limitation of the present invention. In the accompanying drawings:

[0028] Figure 1 It is a structural schematic diagram of a wind farm wake control system provided by the present invention;

[0029] Figure 2 It is a connection diagram of the wind farm wake control system provided by the present invention;

[0030] Figure 3 It is a schematic diagram of the wake control flow of the external controller provided by the present invention.

[0031] Description of Reference Numerals

[0032] 10 External controller 20 Station sector control management subsystem DETAILED DESCRIPTION

[0033] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0034] Figure 1 The structure diagram of the wind farm wake control system provided by the present invention is shown in FIG. Figure 1 As shown, the present invention connects an external controller 10, such as a PLC, in front of the main controller without changing the control logic algorithm in the main controller (original controller) of each unit in the wind farm. The wind speed and direction signals transmitted to the main controller are actively changed through the logic calculation of the external PLC, so as to obtain the desired yaw angle of each wind turbine, and finally realize the active yaw action. First, the external PLC is installed in the nacelle of each wind turbine in the wind farm, and the external PLC is respectively connected to the site sector control management subsystem and the original controller of the current wind turbine, so as to communicate with the original controller of the current wind turbine and the site sector control management subsystem. Specifically, the external PLC can enter the active yaw process according to the wake control start instruction sent by the site sector control management subsystem, and then execute the following active yaw process:

[0035] Get the current wind conditions of the wind turbine;

[0036] The wind condition information of the current wind turbine generator set is compared with the pre-stored yaw angle correction table information, the group corresponding to the wind condition information is determined, and the optimal yaw angle adapted to the wind condition of the current wind turbine generator set is obtained (the yaw angle correction table includes multiple groups of data, each group of data includes wind condition data such as wind speed and direction and its corresponding yaw angle correction value data);

[0037] According to the optimal yaw angle and the wind direction angle currently received by the wind turbine generator set, a target wind direction input value, i.e., an actual received value of the wind direction angle of the main controller of the wind turbine generator set, is obtained by summing the two; and

[0038] The target wind direction input value is sent to the original controller, so that the original controller performs an active yaw action according to the target input value.

[0039] Select a PLC of the same model as the original wind turbine main controller to ensure consistency in indicators such as data scanning speed and data refresh frequency. Keep the original wind farm equipment communication connection framework, and use the original data communication interface for data transmission. On this basis, the external PLC and the station sector control management subsystem 20 are used to achieve data interaction through Ethernet communication, and the wind turbine lower computer and the station upper computer are connected to the wind farm optical fiber through an Ethernet loop to ensure centralized monitoring and data transmission within the wind farm.

[0040] In an embodiment of the present invention, the external PLC is also connected to the wind speed and wind direction measuring device of the current wind turbine group to obtain the wind speed and wind direction of the current wind turbine group provided by the wind speed and wind direction measuring device. Further, the external PLC determines the wind conditions of the current wind turbine group through the wind speed and wind direction of the current wind turbine group. The wind speed and wind direction information can be collected from real-time data measured by sensors such as mechanical anemometers and ultrasonic anemometers, including wind speed and wind direction information detected by two anemometers. The wind direction information includes a wind direction signal A and a wind direction signal B, wherein the wind direction signal A can be a wind direction signal provided by a mechanical anemometer, and the wind direction signal B can be a wind direction signal provided by an ultrasonic anemometer. The wind direction signal A and the wind direction signal B are both actual wind direction signals of the current wind turbine group and participate in the correction calculation of the external controller to obtain the target wind direction input value A1 and the target wind direction input value B1. The target wind direction input value A1 participates in the execution of the yaw action process in the main controller, and the target wind direction input value B1 is used for comparison with A1 to ensure the reliability of the wind direction signal obtained by the measuring device.

[0041] The external PLC installed in each wind turbine group sends the current wind conditions to the site sector control management subsystem when obtaining the current wind conditions of the wind turbine group, so that the site sector control management subsystem can grasp the wind conditions of each wind turbine group in real time and perform corresponding wake control operations.

[0042] Figure 2 The figure shows a connection diagram of the wind farm wake control system provided by the present invention. Figure 2 As shown, the system includes a station sector control management subsystem 20 and multiple wind turbine external controllers. The station sector control management subsystem 20 is used to obtain the wind conditions of the corresponding wind turbine positions sent by the multiple wind turbine external controllers connected to it, and then determine the wind direction information according to the wind conditions, and determine whether to control the corresponding wind turbine to start wake control according to the wind direction information at the location of each wind turbine. Specifically, the station sector control management subsystem 20 determines that the wind direction at the location of the wind turbine is in a stable state within the time period t1, and according to the current average wind direction D obtained by sliding average filtering nIf the wind direction is within the sector management wind direction setting area Ω, a wake control start instruction is sent to the external controller.

[0043] Figure 3 The following is a schematic diagram of the wake flow control process of the external controller provided by the present invention. Figure 3 As shown, before the station sector control management subsystem 20 sends a wake control start instruction to the external controller, the station sector control management subsystem 20 is also used to perform the following operations:

[0044] By collecting wind condition information of corresponding wind turbine generator sets sent by each external controller in real time;

[0045] By performing minute-level sliding average filtering on the wind direction signal of the unit in time period t1, the average wind direction values ​​D1, D2, ..., D n (Where t1 is set to 5 minutes, the wind direction data of the unit is collected in seconds, the wind direction data of 1 minute is calculated, and the filtering operation is performed on a 5-minute time scale, so the value of n is 5);

[0046] By comparing the difference between the average values ​​ΔD with the reference difference D ref The size relationship between them is, if ΔD<D ref , it is determined that the wind direction of the unit is in a stable state during the time period t1;

[0047] Where, ΔD=|D n -D n-1 |+…+|D2-D1|.

[0048] When the wind direction is in a stable state, by determining the current average wind direction D n Whether it falls within the sector management wind direction setting area Ω (Ω consists of multiple wind direction intervals), and whether the unit meets the wake control start conditions under the wind direction in this time period;

[0049] The current average wind direction D n When the wind direction falls within the sector management wind direction setting area Ω of the current wind turbine generator set, an operation of sending a wake control start instruction to the external controller is triggered.

[0050] Specifically, the wake control start / exit function logic includes:

[0051] The operating data of the first row of wind turbines are obtained, wherein the operating data includes wind condition information of the corresponding wind turbines, including wind speed, wind direction, etc.

[0052] A minute-level sliding average filtering operation is performed based on the wind direction data of the first row of units in time period t1. Time period t1 is set to 5 minutes. Since the wind direction signal collected by the unit is a second-level signal, the second-level data is first preprocessed at the minute level.

[0053] According to the sliding average filtering method, the average wind direction D1, D2, ..., D in time period t1 is calculated. n (In this example, the value of n is 5), and the difference is calculated to obtain ΔD and compared with the reference difference D ref For comparison. If ΔD<D ref , it is judged that the wind direction of the unit is in a stable state during this time period, and the prerequisite for executing wake control is met; if ΔD>D ref , it is determined that the wind direction of the unit is unstable during this time period and does not meet the prerequisite for executing wake control. In this case, wake control is not executed and the process operation of updating time period t1 is continued.

[0054] When the wind conditions of the unit are stable, determine the current average wind direction D n Whether it is within the sector management wind direction setting area Ω, that is, D n If it is within the range, it is judged that the sector management conditions are met, the active yaw process is started, and the station sector control management subsystem 20 sends a wake control start instruction to the external controller of the corresponding wind turbine; if it is not within the range, it is judged that the sector management conditions are not met, that is, the wake control is not performed, and the wind turbine still acts according to the original main controller logic.

[0055] When wake control is completed within the time period t1 and the unit completes the active yaw action, the time period t1 is updated. If the wind direction is still stable and the average wind direction D is still stable within the updated time period, n If the sector management wind direction threshold range is still met, wake control will continue to be executed; if the threshold range setting is not met or the wind direction is unstable, wake control will not be executed, and a wake control exit command will be sent to the corresponding external controller to make the corresponding wind turbine of the external controller exit the active yaw process.

[0056] After the external controller receives the wake control start instruction, the external controller 10 traverses and compares the wind condition information of the current wind turbine with the pre-stored yaw angle correction table information, determines the group corresponding to the wind condition information, and obtains the optimal yaw angle suitable for the wind condition of the current wind turbine.

[0057] Among them, the yaw angle correction table can be made in advance, and specifically, the optimization algorithm is used to determine the field-level optimal yaw angle for tabulation. First, the optimal yaw angle is determined based on the historical data of the unit, the wake model and the optimization algorithm, and a table is made in the form of data, and the table is stored in the external PLC. The table contains the correspondence between the wind conditions (wind speed, wind direction) that meet the sector management and the optimal yaw angle. The external PLC performs interval processing on the table and reads the table, and selects the optimal yaw angle to achieve wake control.

[0058] Due to the complexity of the actual turbulent wind conditions, the amount of wind speed and wind direction data corresponding to a certain moment is very large, and these data need to be sorted into intervals in the external PLC. According to the actual wind conditions, the intervals are divided based on the inflow wind direction. The wind direction is -180° to 180°, and 15° is set as an interval, such as 0 to 15°, 16 to 30°, 166 to 180°, etc., so that the corresponding optimal yaw angle is divided into intervals, saving table search time.

[0059] The logical operation of the active yaw action includes: reading the measured current wind speed and direction signal against the interval-processed table to obtain the optimal yaw angle corresponding to the wind condition; then, using the optimal yaw angle and the wind direction angle currently received by the unit to perform logical operations, reversely calculate the target wind direction input value to be input into the main controller of the wind turbine unit, and transmit it and the original wind speed signal to the main controller, so that the wind turbine unit can complete the active yaw action and realize wake control based on the table lookup method.

[0060] The sector management and control subsystem monitors and analyzes the wind speed and direction data and judges the wind conditions (inflow wind direction, wind speed) of the first row of units, and issues wake control start / exit instructions to complete active / passive yaw actions. When the wind conditions meet the conditions and are in the wake control start mode, the actual wind speed and direction signals are transmitted to the external PLC, where the analog signals are converted into digital signals and correction logic operations are performed. The corrected wind speed and direction signals are transmitted to the unit main controller via Ethernet using the TCP / IP protocol. Finally, the main controller transmits the yaw command to the yaw actuator through the original control logic settings to achieve active yaw action.

[0061] When the wind condition does not meet the conditions, that is, the external controller is in the wake control stop mode, the control process is consistent with the original process. The external PLC receives the actual wind speed and direction signal, does not make correction calculations internally, and directly transmits the analog quantity to the unit main controller through the analog output module for logical operation, and finally realizes passive yaw through the yaw actuator. The yaw action is determined by the actual wind speed and direction currently acting on the wind turbine, and does not contain external intervention optimization operations.

[0062] The protection logic of wind turbines includes:

[0063] Each unit's cabin is equipped with an ultrasonic anemometer and a mechanical anemometer. Without the addition of an external controller, both wind direction signal A and wind direction signal B are transmitted to the main controller, of which only wind direction signal A is used for logical calculations, and wind direction signal B is used to compare with wind direction signal A to determine whether the anemometer and wind direction are working properly. For example, when the wind speed is greater than 9m / s, the deviation between wind direction signal A and wind direction signal B is greater than 40°; or when the wind speed is less than 9m / s, the deviation between wind direction signal A and wind direction signal B is greater than 30°, indicating that the wind vane signal is inaccurate or the wind vane is accidentally damaged. At this time, for safety reasons, the wind turbine is shut down.

[0064] After installing an external controller, wind direction signal A and wind direction signal B are transmitted to the external controller. When the external controller fails, both signals cannot be transmitted to the main controller. The main controller determines that wind direction signals A and B are interrupted and takes shutdown measures. If the external controller is normal, the situation is similar to that when the two signals are directly connected to the main controller. When the difference between the two signals exceeds the set value of the wind turbine, it means that there is a problem with the anemometer and wind direction meter, and shutdown measures are taken.

[0065] When the external controller logic operation fails, the error signal is transmitted to the main controller, indicating that the active yaw control command is incorrect. Since the control logic of the original yaw system of the wind turbine has not changed, the unwinding function of the unit can still work. The wind turbine can be unwound when necessary, and can be shut down in an emergency in serious cases.

[0066] The present invention studies the realization of the wake control technology of a wind farm, installs an external controller 10 in the wind farm, realizes the communication connection between the unit level and the station level, realizes the active yaw action and completes the wake control by manually correcting the wind direction signal for the wind speed and direction of a single unit. Its advantage is that it can comprehensively consider the performance differences between different units in the wind farm and the same unit under different wind conditions, consider the active yaw action of multiple units from the hardware implementation aspect, and realize the coordinated control of the wake of the wind farm.

[0067] In field applications, the optimized yaw signal from the wind farm level to the unit level is transmitted to each external controller 10 and acts on each unit, which can ensure that each unit can achieve sufficiently fast, stable and accurate tracking when performing active yaw actions, thereby optimizing and improving the yaw control quality of the unit.

[0068] like Figure 3The schematic diagram of the wake control process of the external controller is shown. When the wind farm wake control device is in the self-control state, the external controller 10 (external PLC) forwards the acquired wind conditions of the current wind turbine to the original controller of the wind turbine and the station sector control management subsystem 20. When the wake control start command sent by the station sector control management subsystem 20 is received, the active yaw process is entered to control the current wind turbine to perform the above-mentioned active yaw operation, and the active yaw process is exited when the wake control exit command is received.

[0069] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included within the scope of the claims of the present application.

Claims

1. A wind farm wake control system, characterized in that: The system comprises: It consists of two parts: external controller and station sector control and management subsystem; The external controller is arranged in the wind turbine generator set, and is respectively connected to the station sector control management subsystem and the original controller of the current wind turbine generator set, and is used to receive the wake control instruction of the station sector control management subsystem, and enter the active yaw process, and the active yaw process includes: Obtain the current wind condition information of the wind turbine; The wind condition information of the current wind turbine generator set is compared with the pre-stored yaw angle correction table information, the group corresponding to the wind condition information is determined, and the optimal yaw angle adapted to the wind condition of the current wind turbine generator set is obtained; Calculating a target wind direction input value according to the optimal yaw angle and the wind direction angle currently received by the wind turbine generator set; and sending the target wind direction input value to the original controller so that the original controller performs an active yaw action according to the target wind direction input value, The station sector control management subsystem is used to perform the following operations: Obtain wind condition information of corresponding wind turbine generator sets sent by each external controller; According to the wind condition information, determine whether the wind direction at the corresponding wind turbine location is in a stable state, and the current wind direction average value D n Is it located in the sector management wind direction setting area? and sends the wake control instruction to the external controller, According to time period Downwind average , calculate the difference between the means Difference from reference If the relationship between , then it indicates the time period The wind direction of the unit is in a stable state; in, , Before the station sector control management subsystem sends the wake control instruction to the external controller, the station sector control management subsystem is further used to: Determine the current average wind direction in steady state Is it located in the sector management wind direction setting area? If yes, sending a wake control start instruction to the external controller; Among them, the sector management wind direction setting area is the wind direction area where the unit is affected by the wake, The station sector control management subsystem is also used to calculate the current wind direction average value Does not fall into the sector management wind direction setting area When the wake control exit instruction is sent to the external controller, the wake control exit instruction is sent to the external controller.

2. The system according to claim 1, characterized in that The external controller is also connected to a wind speed and wind direction measuring device of the current wind turbine generator set, and obtaining the wind condition of the current wind turbine generator set includes receiving the wind speed and wind direction provided by the wind speed and wind direction measuring device.

3. The system according to claim 2, characterized in that The wind speed and wind direction include wind speed and wind direction information detected by two anemometers, and the two anemometers include an ultrasonic anemometer and a mechanical anemometer.

4. The system according to claim 3, characterized in that The wind direction information detected by the two anemometers includes wind direction A and wind direction B; Among them, the wind direction A and wind direction B are both the actual measured wind directions of the current wind turbine and participate in the correction calculation to obtain the corresponding target wind direction input value A1 and target wind direction input value B1; the target wind direction input value A1 participates in the execution of the yaw action process in the main controller, and the target wind direction input value B1 is only used for comparison with A1.

5. The system according to claim 3, characterized in that The cabin of the wind turbine generator set is equipped with one ultrasonic anemometer and one mechanical anemometer.

6. The system according to claim 4, characterized in that If the external controller fails, the wind direction A and wind direction B are not transmitted to the main controller, and shutdown measures are taken; If the external controller is normal, when the difference between the wind direction A and the wind direction B exceeds the set value of the wind turbine generator set, shutdown measures are taken.

7. The system according to claim 1, characterized in that The external controller is also used to send the wind condition information of the current wind turbine generator set to the site sector control and management subsystem.

8. The system according to claim 1, characterized in that The external controller is further used to exit the active yaw process according to the wake control exit instruction sent by the station sector control management subsystem, and perform the following operations when exiting the active yaw process: The wind condition currently being experienced by the wind turbine generator set is acquired, and the wind condition currently being experienced by the wind turbine generator set is forwarded to an original controller of the current wind turbine generator set.

9. The system according to claim 1, characterized in that The pre-stored yaw angle correction table information includes the corresponding relationship between the wind condition of the wind turbine generator set that meets the site sector management and the optimal yaw angle.

10. The system according to claim 9, characterized in that The yaw angle correction table is prepared in advance.

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