Control method and device of wind turbine generator and electronic equipment

Abstract

The invention provides a control method of a wind turbine generator. The method comprises the steps that the voltage of a grid-side converter corresponding to the wind turbine generator is acquired; when the voltage is greater than or equal to a preset voltage threshold value, controlling the grid-side converter to enter the low-voltage ride-through state; the reactive current output quantity of the wind turbine generator is obtained, so that the wind turbine generator is controlled to carry out reactive output according to the reactive current output quantity; and in response to the condition that the grid-side converter is recovered from the low-voltage ride-through state to a normal state, obtaining an active current output quantity of the wind turbine generator, so as to control the wind turbine generator to carry out active output according to the active current output quantity, the reactive power output capability of the grid-side converter can be controlled during the voltage drop period, the active power output capability of the grid-side converter can be controlled during the voltage recovery period, the power grid voltage recovery can be quickly supported, the normal operation of the power system can be ensured, and the safety and reliability of the power system can be ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of power generation, and in particular to a control method, device and electronic equipment for a wind turbine generator set. Background Art

[0002] At present, wind turbines have been widely used in power generation. In order to ensure the safety and reliability of the power system, low voltage ride-through capability has become a technical indicator that wind farms must meet. Relevant regulations (standards) have put forward specific requirements for the fault voltage ride-through capability of wind turbines. This standard not only requires wind turbines to have the ability to operate continuously without disconnecting from the grid when the grid voltage drops, but also to provide reactive current to the system to support system voltage recovery.

[0003] However, in the related technology, the grid-side converter often adopts the grid-side voltage-oriented vector control technology, but it often cannot achieve rapid support for grid voltage recovery. Therefore, how to control the reactive output capacity of the grid-side converter during voltage drop and control the active output capacity of the grid-side converter during voltage recovery to quickly support grid voltage recovery and ensure the normal operation of the power system has become a problem that needs to be solved urgently. Summary of the invention

[0004] The present application provides a control method for a wind turbine group, which is used to control the reactive output capacity of the grid-side converter during voltage drop and control the active output capacity of the grid-side converter during voltage recovery, so as to quickly support grid voltage recovery and ensure the normal operation of the power system.

[0005] According to the first aspect of the present application, a control method for a wind turbine group is provided, comprising: obtaining the voltage of a grid-side converter corresponding to the wind turbine group; in response to the first voltage being greater than or equal to a preset voltage threshold, controlling the grid-side converter to enter the low voltage ride-through state; obtaining the reactive current output of the wind turbine group to control the wind turbine group to perform reactive output according to the reactive current output; in response to the grid-side converter recovering from the low voltage ride-through state to a normal state, obtaining the active current output of the wind turbine group to control the wind turbine group to perform active output according to the active current output.

[0006] According to a second aspect of the present application, a control device for a wind turbine group is provided, comprising: a first acquisition module, used to acquire the voltage of a grid-side converter corresponding to the wind turbine group; a first control module, used to control the grid-side converter to enter the low voltage ride-through state in response to the first voltage being greater than or equal to a preset voltage threshold; a second acquisition module, used to acquire the reactive current output of the wind turbine group to control the wind turbine group to perform reactive output according to the reactive current output; and a second control module, used to acquire the active current output of the wind turbine group in response to the grid-side converter recovering from the low voltage ride-through state to a normal state to control the wind turbine group to perform active output according to the active current output.

[0007] In order to achieve the above-mentioned purpose, the third aspect of the present application proposes an electronic device, characterized in that it includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, and when the processor executes the program, it implements the control method of the wind turbine group as described in the first aspect.

[0008] In order to achieve the above-mentioned purpose, the fourth aspect of the present application proposes a non-transitory computer-readable storage medium storing computer instructions, wherein the computer instructions are used to enable the computer to execute the control method of the wind turbine set described in the first aspect.

[0009] In order to achieve the above-mentioned purpose, the fifth aspect of the present application proposes a computer program product, including a computer program, which implements the control method of the wind turbine generator system according to the first aspect when executed by a processor.

[0010] The technical solution provided by the embodiments of the present application includes at least the following beneficial effects:

[0011] The present application provides a control method for a wind turbine group, which can control the reactive output capacity of the grid-side converter during voltage drop and control the active output capacity of the grid-side converter during voltage recovery, quickly support grid voltage recovery, ensure the normal operation of the power system, and ensure the safety and reliability of the power system.

[0012] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present application, nor is it intended to limit the scope of the present application. Other features of the present application will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The accompanying drawings are used to better understand the present solution and do not constitute a limitation of the present application.

[0014] Figure 1 A schematic flow chart of a control method for a wind turbine generator set provided in an embodiment of the present application;

[0015] Figure 2 A schematic flow chart of another wind turbine control method provided in an embodiment of the present application;

[0016] Figure 3 A schematic flow chart of another wind turbine control method provided in an embodiment of the present application;

[0017] Figure 4 A schematic diagram of the structure of a control device for a wind turbine generator set provided in an embodiment of the present application;

[0018] Figure 5 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0019] The following is a description of exemplary embodiments of the present application in conjunction with the accompanying drawings, including various details of the embodiments of the present application to facilitate understanding, which should be considered as merely exemplary. Therefore, it should be recognized by those of ordinary skill in the art that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present application. Similarly, for the sake of clarity and conciseness, the description of well-known functions and structures is omitted in the following description.

[0020] The control method of the wind turbine generator system of the present application is described in detail below using an embodiment.

[0021] Figure 1 A schematic flow chart of a control method for a wind turbine generator system provided in an embodiment of the present application.

[0022] like Figure 1 As shown, the control method of the wind turbine set proposed in this embodiment specifically includes the following steps:

[0023] S101. Obtain the voltage of the grid-side converter corresponding to the wind turbine generator system.

[0024] Among them, the grid-side converter is composed of a controllable inverter bridge composed of insulated gate bipolar transistors.

[0025] Optionally, the grid-side converter can maintain the stability of the DC-side capacitor voltage, transmit the active power output by the machine-side converter to the grid, and output a given reactive power according to a reactive power reference value.

[0026] It should be noted that the present application does not limit the specific method for obtaining the voltage of the grid-side converter corresponding to the wind turbine generator set, and it can be selected according to actual conditions.

[0027] Optionally, the voltage of the grid-side converter corresponding to the wind turbine generator system may be obtained through a voltage measuring device.

[0028] S102: In response to the voltage being greater than or equal to a preset voltage threshold, controlling the grid-side converter to enter a low voltage ride-through state.

[0029] Among them, the low voltage ride-through state refers to the state in which the wind turbine can remain connected to the grid and even provide a certain amount of reactive power to the grid when the voltage at the wind turbine grid-connected point drops.

[0030] The voltage threshold can be set according to actual conditions.

[0031] It should be noted that after the voltage and the preset voltage threshold are obtained, when the voltage is greater than or equal to the preset voltage threshold, the grid-side converter is controlled to enter a low voltage ride-through state.

[0032] S103: Acquire the reactive current output of the wind turbine generator set to control the wind turbine generator set to perform reactive output according to the reactive current output.

[0033] It should be noted that the specific method for obtaining the reactive current output of the wind turbine is not limited in the present application and can be set according to actual conditions.

[0034] Optionally, a reactive current acquisition device may be used to acquire the reactive current output of the wind turbine generator set.

[0035] Optionally, the reactive current output of the wind turbine generator set may be obtained using a reactive current output calculation formula.

[0036] Furthermore, after the reactive current output is acquired, the wind turbine generator set may be controlled to perform reactive output according to the reactive current output.

[0037] S104, in response to the grid-side converter recovering from the low voltage ride-through state to the normal state, obtaining the active current output of the wind turbine generator set to control the wind turbine generator set to perform active power output according to the active current output.

[0038] It should be noted that during the low voltage ride-through state (fault period), it is necessary to prioritize the ability of wind turbines to provide reactive power output to the grid. Therefore, a reactive power priority control strategy is adopted, that is, under the premise of inverter capacity constraints, reactive current control is prioritized, and then active current output is performed to control the wind turbines to output active power according to the active current output.

[0039] It should be noted that the specific method for obtaining the active current output of the wind turbine generator system is not limited in the present application and can be set according to actual conditions.

[0040] Optionally, an active current acquisition device may be used to acquire the active current output of the wind turbine generator set.

[0041] Optionally, the active current output calculation formula may be used to obtain the active current output of the wind turbine generator set.

[0042] Furthermore, after the active current output is acquired, the wind turbine generator set may be controlled to perform active output according to the active current output.

[0043] It should be noted that for the grid-side converter, the grid-side voltage-oriented vector control technology is generally used to coincide the d-axis of the synchronous rotating coordinate system with the grid voltage comprehensive vector. At this time, the projection of the grid voltage on the q-axis is 0, that is,

[0044]

[0045] Where: u gd is the d-axis component of the grid voltage, u gq is the q-axis component of the grid voltage, e g is the comprehensive vector of grid-side voltage.

[0046] Among them, the active power and reactive power exchanged between the grid-side converter and the grid can be expressed as:

[0047]

[0048] Where: P g is the active power exchanged between the grid-side inverter and the grid, Q g is the reactive power exchanged between the grid-side inverter and the grid, i gd is the grid-side d-axis current, i gq is the grid-side q-axis current.

[0049] In the embodiment of the present application, in response to the grid-side converter being in a normal state, it is determined that the reactive current output of the wind turbine is zero.

[0050] It should be noted that when the grid-side converter is in a normal state, that is, when the grid-side converter operates normally, the grid-side converter determines the reference value i of the d-axis current by controlling the DC side voltage in order to maintain the DC side capacitor voltage stable. gdref In addition, in order to achieve unity power factor operation of wind turbines, the reactive current output is usually set to 0. At this time, the reference value of the q-axis current i gqref Also 0.

[0051] The control method of the wind turbine group provided in the present application obtains the voltage of the grid-side converter corresponding to the wind turbine group; in response to the voltage being greater than or equal to a preset voltage threshold, the grid-side converter is controlled to enter a low voltage ride-through state, and the reactive current output of the wind turbine group is obtained to control the wind turbine group to perform reactive output according to the reactive current output; in response to the grid-side converter recovering from the low voltage ride-through state to the normal state, the active current output of the wind turbine group is obtained to control the wind turbine group to perform active output according to the active current output. The present application can control the reactive output capacity of the grid-side converter during voltage drop and control the active output capacity of the grid-side converter during voltage recovery to normal, quickly support grid voltage recovery, ensure the normal operation of the power system, and ensure the safety and reliability of the power system.

[0052] The following explains the process of obtaining the reactive current output and the active current output respectively.

[0053] As a possible implementation method for the first reactive current output, Figure 2 As shown, based on the above steps, the specific process of obtaining the reactive current output of the wind turbine generator set in the above step S103 to control the wind turbine generator set to perform reactive output according to the reactive current output includes the following steps:

[0054] S201. Obtain the current grid fault voltage and the rated current of the wind turbine generator set.

[0055] Optionally, the current grid fault voltage may be obtained by a voltage measuring device.

[0056] It should be noted that the rated current of the wind turbine is the current of the wind turbine under normal working conditions. The current of the wind turbine under normal working conditions can be measured to obtain the rated current I of the wind turbine. N .

[0057] S202. Obtain a reactive output coefficient according to the rated current of the wind turbine generator set.

[0058] It should be noted that, due to the limitation of the output capacity of the wind turbine generator set, the reactive output coefficient can be obtained according to the rated current of the wind turbine generator set.

[0059] Optionally, the reactive output coefficient may be obtained by querying a mapping relationship between the rated current of the wind turbine generator set and the reactive output coefficient, for example, the K value is 2.

[0060] S203: Obtain reactive current output according to the current grid fault voltage, the rated current of the wind turbine generator set and the reactive output coefficient.

[0061] It should be noted that the reactive current output I can be obtained according to the reactive current output formula:gqref :

[0062] I gqref =K×(0.9-U T )I N ,(0.2≤U T ≤0.9)

[0063] Among them, I gqref is the reactive current output, K is the first reactive output coefficient, U T is the current grid fault voltage, I N is the rated current of the wind turbine.

[0064] In the embodiment of the present application, after the reactive current output of the wind turbine generator set is acquired, the wind turbine generator set may be controlled to perform reactive output according to the reactive current output.

[0065] Furthermore, after controlling the wind turbine to perform reactive output according to the reactive current output, the grid-side converter recovers from the low voltage ride-through state to a normal state.

[0066] As a possible implementation method for active current output, Figure 3 As shown, based on the above steps, the specific process of obtaining the active current output of the wind turbine generator set in the above step S104 to control the wind turbine generator set to perform active output according to the active current output includes the following steps:

[0067] S301. Obtain an active current reference value.

[0068] Among them, the active current reference value is the active current reference value I obtained by controlling the DC side voltage. gd1 .

[0069] S302: Determine the active current output of the wind turbine generator system from the upper limit value of the active current output and the active current reference value.

[0070] It should be noted that the present application does not limit the specific method for obtaining the upper limit value of the active current output, which can be selected according to actual conditions.

[0071] Optionally, the current upper limit value of the grid-side converter may be obtained, and the upper limit value of the active current output of the wind turbine generator system may be determined according to the reactive current output and the current upper limit value.

[0072] For example, the following formula can be used to determine the upper limit value I of the active current output of the wind turbine: dmax :

[0073]

[0074] Among them, I dmaxis the upper limit of active current output, I max is the current upper limit of the grid-side converter, I gqref Reactive current output.

[0075] In the application embodiment, after the upper limit value of the active current output and the active current reference value are obtained, the active current output of the wind turbine generator set can be determined from the upper limit value of the active current output and the active current reference value.

[0076] For example, a smaller value can be selected from the upper limit value of the active current output and the active current reference value as the active current output, that is, I gdref =min{I gd1 , I dmax}.

[0077] It should be noted that when the fault is eliminated, that is, the grid-side converter recovers from the low voltage ride-through state to the normal state, if the active power has not recovered to the level before the low voltage ride-through when the voltage returns to normal, the active current should be controlled to recover to the normal value according to the specified slope, so that the active current can be controlled according to the recovery slope to reduce the impact of the sudden change in active power on the wind turbine during the voltage recovery period.

[0078] The present application provides a control method for a wind turbine group, which can control the reactive output capacity of the grid-side converter during voltage drop and control the active output capacity of the grid-side converter during voltage recovery, quickly support grid voltage recovery, ensure the normal operation of the power system, and ensure the safety and reliability of the power system.

[0079] In order to implement the above embodiment, this embodiment provides a control device for a wind turbine generator set. Figure 4 A schematic structural diagram of a control device for a wind turbine set provided in an embodiment of the present application.

[0080] like Figure 4 As shown, the control device 1000 of the wind turbine generator system includes: a first acquisition module 110 , a first control module 120 , a second acquisition module 130 and a second control module 140 .

[0081] A first acquisition module 110 is used to acquire the voltage of the grid-side converter corresponding to the wind turbine generator set;

[0082] A first control module 120, configured to control the grid-side converter to enter the low voltage ride-through state in response to the first voltage being greater than or equal to a preset voltage threshold;

[0083] A second acquisition module 130 is used to acquire the reactive current output of the wind turbine generator set, so as to control the wind turbine generator set to perform reactive output according to the reactive current output;

[0084] The second control module 140 is used to obtain the active current output of the wind turbine generator set in response to the grid-side converter recovering from the low voltage ride-through state to the normal state, so as to control the wind turbine generator set to perform active output according to the active current output.

[0085] According to one embodiment of the present application, the second acquisition module 120 is used to: obtain the current grid fault voltage and the rated current of the wind turbine set; obtain the reactive output coefficient based on the rated current of the wind turbine set; obtain the reactive current output based on the current grid fault voltage, the rated current of the wind turbine set and the reactive output coefficient.

[0086] According to one embodiment of the present application, the device 1000 is further used to: obtain the current upper limit value of the grid-side converter; and determine the upper limit value of the active current output of the wind turbine according to the reactive current output and the current upper limit value.

[0087] According to an embodiment of the present application, the second control module 140 is used to: obtain an active current reference value, and determine the active current output of the wind turbine from the upper limit value of the active current output and the active current reference value.

[0088] According to an embodiment of the present application, the device 1000 is further used to: in response to the grid-side converter being in a normal state, determine that the reactive current output of the wind turbine is zero.

[0089] The control device of the wind turbine group provided in the present application obtains the voltage of the grid-side converter corresponding to the wind turbine group; in response to the voltage being greater than or equal to a preset voltage threshold, controls the grid-side converter to enter a low voltage ride-through state, obtains the reactive current output of the wind turbine group, so as to control the wind turbine group to perform reactive output according to the reactive current output; in response to the grid-side converter recovering from the low voltage ride-through state to the normal state, obtains the active current output of the wind turbine group, so as to control the wind turbine group to perform active output according to the active current output. The present application can control the reactive output capacity of the grid-side converter during voltage drop and control the active output capacity of the grid-side converter during voltage recovery to normal, quickly support grid voltage recovery, ensure the normal operation of the power system, and ensure the safety and reliability of the power system.

[0090] In order to implement the above embodiment, the present application also proposes an electronic device 2000, such as Figure 5 As shown, it includes: a memory 210, a processor 220, and a computer program stored in the memory 210 and executable on the processor 220. When the processor executes the program, the control method of the wind turbine set as described in the first aspect is implemented.

[0091] In order to implement the above embodiment, the present application proposes a non-transitory computer-readable storage medium storing computer instructions, wherein the computer instructions are used to enable the computer to execute the control method of the wind turbine set described in the first aspect.

[0092] In order to implement the above embodiments, the present application also proposes a computer program product, including a computer program, which implements the control method of the wind turbine set described in the first aspect when executed by a processor.

[0093] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps recorded in this application can be executed in parallel, sequentially or in different orders, as long as the expected results of the technical solution disclosed in this application can be achieved, and this document is not limited here.

[0094] The above specific implementations do not constitute a limitation on the protection scope of this application. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of this application should be included in the protection scope of this application.

Claims

1. A control method for a wind turbine generator system, comprising: Obtaining the voltage of the grid-side converter corresponding to the wind turbine; In response to the voltage being greater than or equal to a preset voltage threshold, controlling the grid-side converter to enter the low voltage ride-through state; Acquiring the reactive current output of the wind turbine generator set to control the wind turbine generator set to perform reactive output according to the reactive current output; In response to the grid-side converter recovering from the low voltage ride-through state to a normal state, the active current output of the wind turbine generator set is obtained to control the wind turbine generator set to perform active power output according to the active current output.

2. The method according to claim 1, characterized in that: The obtaining of the reactive current output of the wind turbine generator set comprises: Obtaining the current grid fault voltage and the rated current of the wind turbine generator set; Obtaining a reactive output coefficient according to the rated current of the wind turbine generator set; The reactive current output is obtained according to the current grid fault voltage, the rated current of the wind turbine generator set and the reactive output coefficient.

3. The method according to claim 1, characterized in that Before obtaining the active current output of the wind turbine generator set, the method includes: Obtaining a current upper limit value of the grid-side converter; An upper limit value of the active current output of the wind turbine generator system is determined according to the reactive current output and the current upper limit value.

4. The method according to claim 3, characterized in that: The obtaining of the active current output of the wind turbine generator set comprises: Get active current reference value; The active current output of the wind turbine generator set is determined from the upper limit value of the active current output and the active current reference value.

5. The method according to claim 1, characterized in that The method further comprises: In response to the grid-side converter being in a normal state, it is determined that the reactive current output of the wind turbine group is zero.

6. A control device for a wind turbine generator system, comprising: A first acquisition module is used to acquire the voltage of the grid-side converter corresponding to the wind turbine generator set; A first control module, configured to control the grid-side converter to enter the low voltage ride-through state in response to the voltage being greater than or equal to a preset voltage threshold; A second acquisition module is used to acquire the reactive current output of the wind turbine generator set to control the wind turbine generator set to perform reactive output according to the reactive current output; The second control module is used to obtain the active current output of the wind turbine group in response to the grid-side converter recovering from the low voltage ride-through state to the normal state, so as to control the wind turbine group to perform active output according to the active current output.

7. The device according to claim 6, characterized in that The second acquisition module is used to: Obtaining the current grid fault voltage and the rated current of the wind turbine generator set; Obtaining a reactive output coefficient according to the rated current of the wind turbine generator set; The reactive current output is obtained according to the current grid fault voltage, the rated current of the wind turbine generator set and the reactive output coefficient.

8. An electronic device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the control method for the wind turbine set according to any one of claims 1 to 5 is implemented.

9. A non-transitory computer-readable storage medium storing computer instructions, wherein: The computer instructions are used to enable the computer to execute the control method for the wind turbine generator set according to any one of claims 1-5.

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