A wind power reactive power reserve setting method and device based on high-voltage ride-through control

Abstract

The application provides a wind power reactive reserve setting method and device based on high-voltage penetration control, first, the relevant transient characteristic parameters of synchronous units and wind farms in the system are obtained, the internal topology structure of the wind farm is analyzed, and the inherent impedance of the whole wind farm on the grid side is derived; then, the high-voltage penetration control link is impedance converted in combination with the voltage regulation mechanism of the wind power; then, the network admittance matrix is obtained from the power flow result, and the modified network admittance matrix is constructed in combination with the transient characteristic parameters of the synchronous units and the inherent impedance and the converted impedance of the wind power; finally, the reactive power reserve demand of the wind farm is quantitatively set in combination with the reactive power margin boundary, the transient overvoltage safety threshold and the steady-state constraint condition of the admittance matrix. The application can accurately quantify the reactive power reserve demand of the wind farm, thereby improving the voltage stability level of the sending end grid under the DC blocking fault and the reliability of the wind power grid operation.

Description

Technical Field

[0001] This invention relates to the field of power system control technology, and in particular to a method and device for setting reactive power reserve of wind power based on high voltage ride-through control. Background Technology

[0002] Ultra-high voltage direct current (UHVDC) transmission boasts significant economic and technological advantages in long-distance power transmission and large-scale power dispatch. UHVDC converter stations are typically equipped with large-scale AC filter devices and parallel capacitor banks to meet their reactive power requirements. When the DC system is blocked due to a fault, the reactive power regulation equipment cannot be shut down immediately, causing a large amount of surplus reactive power to flow back into the sending-end AC grid, resulting in a significant increase in the grid's transient voltage.

[0003] Sending-end AC systems are often adjacent to or directly connected to large-scale wind power clusters, and wind power is highly sensitive to voltage fluctuations. Under the aforementioned transient overvoltage conditions, wind turbines are prone to grid disconnection due to overvoltage protection triggering, which can induce secondary faults such as power imbalance and frequency fluctuations, seriously threatening the safe and stable operation of the system. To mitigate the adverse effects of transient overvoltages on wind power, it is necessary to fully explore the reactive power voltage support potential of wind power itself. Existing research mainly focuses on reactive power control strategies for wind power during steady-state or fault periods, lacking a systematic setting method for the reactive power reserve capacity of wind farms under extreme disturbances such as DC blocking. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a method and apparatus for setting reactive power reserve in wind power based on high-voltage ride-through control.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical method: a wind power reactive power reserve setting method based on high-voltage ride-through control, which is used in the power system after wind power participates in grid voltage regulation, the method includes: Step S1: Collect the subtransient impedance of the synchronous machine in the system and the relevant transient characteristic parameters of the wind farm, and calculate the overall grid-side inherent impedance of the wind farm; Step S2: Based on the voltage regulation mechanism of wind power, analyze the interaction between the reactive power regulation of wind power and the voltage change at the grid connection point, and perform impedance conversion on the high voltage ride-through control link of the wind farm. Step S3: Obtain the network admittance matrix from the system power flow results, and then combine the subtransient impedance of the synchronous machine, the inherent impedance of the grid side of the wind farm as a whole, and the converted impedance of the high voltage ride control link of the wind farm to construct the modified network admittance matrix. Then, based on the modified network admittance matrix, derive the formula for calculating the peak voltage of the wind farm outlet after the fault. Step S4: Quantitatively adjust the reactive power reserve requirement of the wind farm by taking into account the reactive power margin boundary, transient overvoltage safety threshold and admittance matrix steady-state constraints.

[0006] Furthermore, in step S1, based on the relevant transient characteristic parameters of the wind farm in the system, including the overall magnetic flux leakage ratio of the wind farm, stator transient reactance, relaxation time constant of the DC component of the stator and rotor windings, excitation coupling inductance, stator inductance and leakage inductance, and rotor inductance and leakage inductance, an expression for the short-circuit current after a wind farm fault is constructed. Then, the short-circuit current expression is simplified based on the fact that the fault time is zero, to obtain an expression for calculating the inherent impedance of the grid side of the wind farm as a whole.

[0007] Furthermore, in step S2, the method for calculating the impedance of the high-voltage ride-through control loop in the wind farm is as follows: First, the wind farm is set up. shaft current Equal to the entire wind farm Shaft stator current The reactive current of the wind farm under different states is obtained as follows: (1) In the formula: This refers to the output voltage of the wind farm. and These are the high-voltage ride-through control parameters. This represents the reactive current prior to the fault. This is the nominal voltage of the wind farm. For the active power output of the wind farm For the power angle of the wind farm, The voltage threshold for whether a wind farm can undergo high-voltage ride-through; Next, combining the voltage regulation mechanism of wind power and formula (1), the high-voltage ride-through control of the wind farm is converted into impedance as shown in formula (2). The voltage regulation mechanism of wind power is: when the system encounters a fault leading to More than 1.1 times At that time, wind power needs to be controlled By changing its reactive power output, voltage regulation can be achieved. (2) (3) In the formula: The equivalent impedance for high-voltage ride-through control in wind farms; and These represent the wind farm outlet voltage before the fault and the wind farm outlet voltage increment after the fault, respectively. Then, the interaction between the reactive power regulation of wind power and the voltage change at the grid connection point is analyzed to determine the change in reactive power output of the wind farm during high-voltage ride-through. Normalized representation: (4) In the formula, , , , , , They are respectively , , , , , The normalized value; Finally, the equivalent impedance for high-voltage ride-through control in wind farms is derived. Normalized representation: (5) In the formula, , They are respectively , The normalized value.

[0008] Furthermore, in step S3, the method for calculating the peak value of the wind farm outlet voltage after the fault is as follows: First, obtain the normalized value of the network admittance matrix from the system power flow results. Its expression is: (6) Where n represents the number of system nodes, and f represents the node where the converter station is located; Represents a node With nodes The normalized value of the mutual admittance between them. Represents a node The normalized value of the auto-admittance, ; Then, the corrected self-admittance expressions for the synchronous generator units and wind farms in the system are determined respectively; 1) The self-admittance of the synchronous generator is corrected based on the normalized value of the subtransient impedance of the synchronous generator, as shown in the following formula: (7) In the formula: This indicates the node where the synchronous generator unit is located. and The first The normalized values ​​of the self-admittance and modified self-admittance of each node. and These are the base capacity and normalized subtransient reactance of the synchronous generator unit, respectively. This serves as the baseline value for system capacity. 2) The self-admittance of the wind farm is corrected based on the inherent impedance of the grid side of the wind farm as a whole and the equivalent impedance of the high-voltage ride-through control link of the wind farm, as shown in the following formula: (8) In the formula: Indicates the node where the wind farm is located. and The first The normalized values ​​of the self-admittance and modified self-admittance of each node. This is the baseline capacity located in the wind farm; The magnetic flux leakage ratio is located throughout the wind farm. This represents the normalized value of the stator transient reactance for the entire wind farm. This is the normalized value of the converted impedance for high-voltage ride-through control in the wind farm; Next, based on the DC blocking condition being approximated as injecting an equivalent current source at the fault location, the relationship between the current and voltage change vectors of the converter station after the fault is determined, and the corrected network admittance matrix is ​​constructed. (9) (10) In the formula: , and These are the short-circuit capacity of the converter station nodes, and the normalized values ​​of reactive power and voltage changes caused by DC blocking at the converter station, respectively. and This is a normalized vector of the changes in current and voltage at each node after a fault. According to The corrected network admittance matrix; Finally, based on the corrected network admittance matrix, the expression for the voltage change at each node in the network is determined: (11) In the formula, This is the normalized value of the current change at the converter station node after the fault. The corrected self-admittance for converter station nodes; Simplifying equation (11) yields: (12) In the formula: The corrected self-impedance of node f in the system. This is the corrected mutual impedance between node n and node f in the system; Based on this, the normalized value of the voltage change of any wind farm in the network is derived as follows: (13) In the formula: For nodes in the system Corrected mutual impedance between node f; Combining equations (3) and (13), the normalized value of the peak value of the wind farm outlet voltage after the fault is obtained. Characterized as: (14)

[0009] Furthermore, in step S4, a model is established with the goal of minimizing the total reactive power reserve requirement provided by the high voltage ride-through control of the wind farm under DC blocking conditions, taking into account the reactive power margin boundary, the transient overvoltage safety threshold and the steady-state constraint of the admittance matrix. The reactive power reserve requirement of the wind farm is then quantitatively tuned. (15) In the formula: Represents a collection of wind farms; and These represent the normalized values ​​of reactive power output and reactive power output change during the high-voltage ride-through process of the wind farm, respectively. This represents the reactive power reserve requirement of a normalized wind farm. This is the upper limit for reactive power in wind farms; This is the normalized threshold for the wind farm's outlet voltage. For the corrected network impedance matrix; It is an identity matrix.

[0010] Preferably, in step S4, the steady-state constraint condition of the admittance matrix is ​​replaced by the following constraint: (16) In the formula: and Represent matrices respectively and The List.

[0011] As another aspect of the present invention, a wind power reactive power reserve setting device based on high voltage ride-through control includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the aforementioned wind power reactive power reserve setting method based on high voltage ride-through control.

[0012] As another aspect of the present invention, a computer-readable storage medium is provided, on which a computer program is stored, which, when executed by a processor, implements the aforementioned wind power reactive power reserve setting method based on high voltage ride-through control.

[0013] As another aspect of the present invention, a computer program product includes a computer program that, when executed by a processor, implements the aforementioned wind power reactive power reserve setting method based on high voltage ride-through control.

[0014] This invention proposes a method and apparatus for setting reactive power reserve in wind power based on high-voltage ride-through control. By establishing a converted impedance model of the high-voltage ride-through control characteristics of wind power, it reveals the intrinsic correlation between reactive power reserve in wind farms and the transient voltage response of the system. This method eliminates the need for simulation calculations, thus significantly shortening the setting time. First, by equating the high-voltage ride-through control characteristics of the wind farm to impedance form, the complexity of system analysis is simplified. Second, the network matrix required for voltage calculation is corrected based on this equivalent impedance. This process effectively improves the calculation accuracy of the peak voltage at the wind farm outlet, thereby achieving high-precision setting of the reactive power reserve requirements of the wind farm. It also effectively suppresses transient overvoltages during high-voltage ride-through, ensuring they remain below the safe threshold. Furthermore, it does not rely on a specific simulation platform, demonstrating good adaptability and practical engineering value. Attached Figure Description

[0015] Figure 1 This is a flowchart of the wind power reactive power reserve setting method based on high voltage ride-through control involved in this invention; Figure 2 The IEEE 39-node system topology diagram modified in the simulation experiment of the embodiment of the present invention; Figure 3 The following are comparison charts of the peak output voltage curves of each wind farm before and after the activation of high voltage ride-through control in the simulation test of the embodiment of the present invention (wherein, (a) is a comparison chart of the peak output voltage curves of wind farm W1 before and after the activation of high voltage ride-through control; (b) is a comparison chart of the peak output voltage curves of wind farm W2 before and after the activation of high voltage ride-through control; (c) is a comparison chart of the peak output voltage curves of wind farm W3 before and after the activation of high voltage ride-through control; and (d) is a comparison chart of the peak output voltage curves of wind farm W4 before and after the activation of high voltage ride-through control). Detailed Implementation

[0016] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to embodiments and accompanying drawings. The content mentioned in the embodiments is not intended to limit the present invention.

[0017] like Figure 1 As shown, a wind power reactive power reserve setting method based on high voltage ride-through control is used in power systems after wind power participates in grid voltage regulation. The method specifically includes the following steps.

[0018] Step S1: Collect the subtransient impedance of the synchronous machine in the system and the relevant transient characteristic parameters of the wind farm, and calculate the overall grid-side inherent impedance of the wind farm.

[0019] Based on the relevant transient characteristic parameters of the wind farm in the system, including the overall magnetic flux leakage ratio of the wind farm, stator transient reactance, relaxation time constant of the DC component of the stator and rotor windings, excitation coupling inductance, stator inductance and leakage inductance, and rotor inductance and leakage inductance, an expression for the short-circuit current after a wind farm fault is constructed.

[0020] After a wind farm failure Short-circuit current at any moment The calculation formula is: (16) In the formula: This represents the effective value of the wind farm's outlet voltage before the fault. The synchronization angular frequency; 、 , , These are the overall flux leakage ratio of the wind farm, the stator transient reactance, and the relaxation time constant of the DC component of the rotor winding, respectively. With stator transient inductance The calculation formula is as follows: (17) (18) In the formula: , , , , These are the excitation coupling inductance, stator inductance, stator leakage inductance, rotor inductance, and rotor leakage inductance of the entire wind farm. and The calculation formula is as follows: (19) (20) Because when When =0, Therefore, the inherent impedance of the entire wind farm on the grid side can be taken as... .

[0021] Step S2: Based on the voltage regulation mechanism of wind power, analyze the interaction between the reactive power regulation of wind power and the voltage change at the grid connection point, and perform impedance conversion on the high voltage ride-through control link of the wind farm.

[0022] First, the wind farm is set up. shaft current Equal to the entire wind farm Shaft stator current The reactive current of the wind farm under different states is: (1) In the formula: This refers to the output voltage of the wind farm. and These are the high-voltage ride-through control parameters. This represents the reactive current prior to the fault. This is the nominal voltage of the wind farm. For the active power output of the wind farm For the power angle of the wind farm, This is the voltage threshold for whether a wind farm can undergo high-voltage ride-through.

[0023] When the system encounters a malfunction, leading to More than 1.1 times At that time, wind power needs to be controlled By altering its reactive power output, voltage regulation can be achieved. Therefore, the high-voltage ride-through control of a wind farm can be converted into impedance: (2) In the formula: This is the equivalent impedance for high-voltage ride-through control in wind farms.

[0024] The formula for calculation is: (3) In the formula: and These represent the wind farm outlet voltage before the fault and the increase in wind farm outlet voltage after the fault, respectively.

[0025] The reference values ​​for voltage and current in the system satisfy the following relationship: (twenty one) In the formula: , and These are the reference values ​​for voltage, current, and capacity in the system, respectively.

[0026] The formula for calculating the reactive power output of a wind farm is: (twenty two) In the formula: and These are the reactive power output and stator voltage of the wind farm, respectively.

[0027] Combined , and The calculation formula can be used to obtain the change in reactive power output of the wind farm during the high-voltage ride-through process. Normalized representation: (4) In the formula, , , , , , They are respectively , , , , , The normalized value.

[0028] From this, the equivalent impedance of the high-pass control of the wind farm can be obtained. Normalized representation: (5) In the formula, , They are respectively , The normalized value.

[0029] Step S3: Obtain the network admittance matrix from the system power flow results, and then combine the subtransient impedance of the synchronous machine, the inherent impedance of the grid side of the wind farm as a whole, and the converted impedance of the high voltage ride control link of the wind farm to construct the modified network admittance matrix. Based on the modified network admittance matrix, derive the formula for calculating the peak voltage of the wind farm outlet after the fault.

[0030] First, obtain the normalized value of the network admittance matrix from the system power flow results. Its expression is: (6) Where n represents the number of system nodes, and f represents the node where the converter station is located; Represents a node With nodes The normalized value of the mutual admittance between them. Represents a node The normalized value of the auto-admittance, .

[0031] and According to Correcting its own self-admittance, The self-admittance of the synchronous generator is corrected based on the normalized value of the subtransient impedance of the synchronous generator, as shown in the following equation: (7) In the formula: This indicates the node where the synchronous generator unit is located. and The first The normalized values ​​of the self-admittance and modified self-admittance of each node. and These are the base capacity and normalized subtransient reactance of the synchronous generator unit, respectively. This serves as the baseline value for system capacity.

[0032] The self-admittance of the wind farm is corrected based on the inherent impedance of the grid side of the wind farm as a whole and the equivalent impedance of the high-voltage ride-through control link of the wind farm, as shown in the following formula: (8) In the formula: Indicates the node where the wind farm is located. and The first The normalized values ​​of the self-admittance and modified self-admittance of each node. This is the baseline capacity located in the wind farm; The magnetic flux leakage ratio is located throughout the wind farm. This represents the normalized value of the stator transient reactance for the entire wind farm. This is the normalized value of the converted impedance for high-voltage ride-through control in wind farms.

[0033] The voltage change at the converter station can be expressed as: (9) In the formula: , and These represent the short-circuit capacity of the converter station nodes and the normalized values ​​of reactive power and voltage changes caused by DC blocking at the converter station, respectively.

[0034] The DC blocking condition can be approximated as injecting an equivalent current source at the fault location, and its matrix form can be expressed as: (10) In the formula: and This is a normalized vector of the changes in current and voltage at each node after a fault. According to The corrected network admittance matrix.

[0035] In the injected equivalent current source, the injected current is non-zero only at the DC blocking point, and zero at all other nodes. Therefore, the voltage change at each point in the network can be expressed as: (11) In the formula, This is the normalized value of the current change at the converter station node after the fault. This is the corrected self-admittance for the converter station node.

[0036] Simplifying equation (11) yields: (12) In the formula: The corrected self-impedance of node f in the system. This is the corrected mutual impedance between node n and node f in the system.

[0037] Based on this, the voltage change of any wind farm in the network is derived as follows: (13) In the formula: For nodes in the system The corrected mutual impedance between node f and node f.

[0038] Combining equations (3) and (13), the normalized value of the peak value of the wind farm outlet voltage after the fault is obtained. Characterized as: (14).

[0039] Step S4: Integrating the reactive power margin boundary, transient overvoltage safety threshold, and admittance matrix steady-state constraints, a model is established with the objective of minimizing the total reactive power reserve demand provided by the high-voltage ride-through control of the wind farm under DC blocking conditions, as shown in the following equation: (15) In the formula: Represents a collection of wind farms; and These represent the normalized values ​​of reactive power output and reactive power output change during the high-voltage ride-through process of the wind farm, respectively. This represents the reactive power reserve requirement of a normalized wind farm. This is the upper limit for reactive power in wind farms; This is the normalized threshold for the wind farm's outlet voltage. For the corrected network impedance matrix; It is an identity matrix.

[0040] Because the total number of system nodes is large, if directly using As a constraint, the model solution is quite burdensome. Given that the proportion of wind farms relative to the total number of nodes is not high, the following constraint can preferably replace the steady-state constraint condition of the admittance matrix in formula (15): (16) In the formula: and Represent matrices respectively and The List.

[0041] According to formula (15), the reactive power reserve requirements of wind farms can be quantitatively set.

[0042] On the other hand, based on the same principle as the wind power reactive power reserve setting method based on high-voltage ride-through control described in the above embodiments, the present invention also provides a wind power reactive power reserve setting device based on high-voltage ride-through control. This device includes a memory, a processor, and a computer program stored in the memory. The processor executes the computer program to implement the wind power reactive power reserve setting method based on high-voltage ride-through control described in the above embodiments. Specifically, the device can be an electronic computer or tablet computer, the processor can be a CPU, GPU, etc., and the memory can be RAM, ROM, EEPROM, CDROM, disk storage medium, or any other medium capable of carrying or storing the computer program and capable of being read by a computer; no limitation is made herein.

[0043] On the other hand, the present invention also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the wind power reactive power reserve setting method based on high-voltage ride-through control described in the above embodiments. Specifically, the computer-readable storage medium may be RAM, ROM, EEPROM, SSD, CDROM, DVD, USB flash drive, or any other medium capable of carrying or storing a computer program and capable of being read by a computer.

[0044] On the other hand, the present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the wind power reactive power reserve setting method based on high voltage ride-through control described in the above embodiments.

[0045] To demonstrate the effectiveness and accuracy of this invention, simulation experiments will be conducted on it below, such as... Figure 2 As shown, this simulation uses a modified IEEE 39-node system. In the figure, G1-G10 represent the ten synchronous generators in the system, R represents the receiving-end grid, and W1-W4 represent the four wind farms in the system. The system load peak is stable at 5849MW. A new DC transmission channel with a rated transmission capacity of 3000MW is added at node 23 to transmit power to the target grid. The locations and capacities of the wind farms are shown in the figure. Figure 2 The wind farm voltage threshold was selected as 1.3 pu. This experiment selected DC bipolar blocking as a typical system disturbance scenario, with a DC transmission power of 2350 MW. The high-voltage ride-through control parameters of the wind farm, tuned according to the method proposed in this invention, were substituted into the simulation system. The resulting peak output voltage and total reactive power reserve demand before and after the activation of high-voltage ride-through control are shown in Table 1. The peak output voltage curves are compared below. Figure 3 As shown.

[0046] Table 1 Reactive power reserve setting results for wind farms ; from Figure 3 As can be seen, the method proposed in this invention can accurately determine the reactive power required by the wind farm, thereby effectively suppressing the transient output voltage of the wind farm nodes during high-voltage ride-through and ensuring that it is always maintained below the preset safety threshold. The comparison results in Table 1 further verify the accuracy and engineering applicability of the method. Specifically, in wind farms W1 and W2, the actual absorbed reactive power is 328.19 Mvar and 430.78 Mvar, respectively, while the reactive power demand determined by this method is 353.7 Mvar and 439.86 Mvar, respectively, with relative errors of only 7.77% and 2.11%, respectively. The above results show that the method proposed in this invention can achieve high-precision determination of reactive power demand under different wind farm conditions, and has good adaptability and reliability.

[0047] The above embodiments are preferred implementations of the present invention. In addition, the present invention can be implemented in other ways. Any obvious substitutions without departing from the concept of the present technical solution are within the protection scope of the present invention.

[0048] To facilitate understanding by those skilled in the art of the improvements of this invention over the prior art, some of the accompanying drawings and descriptions have been simplified, and for clarity, some other elements have been omitted from this application. Those skilled in the art should realize that these omitted elements may also constitute the content of this invention.

Claims

1. A wind power reactive power reserve setting method based on high-voltage ride-through control, used in power systems after wind power participates in grid voltage regulation, characterized in that: Step S1: Collect the subtransient impedance of the synchronous machine in the system and the relevant transient characteristic parameters of the wind farm, and calculate the overall grid-side inherent impedance of the wind farm; Step S2: Based on the voltage regulation mechanism of wind power, analyze the interaction between the reactive power regulation of wind power and the voltage change at the grid connection point, and perform impedance conversion on the high voltage ride-through control link of the wind farm. Step S3: Obtain the network admittance matrix from the system power flow results, and then combine the subtransient impedance of the synchronous machine, the inherent impedance of the grid side of the wind farm as a whole, and the converted impedance of the high voltage ride control link of the wind farm to construct the modified network admittance matrix. Then, based on the modified network admittance matrix, derive the formula for calculating the peak voltage of the wind farm outlet after the fault. Step S4: Quantitatively adjust the reactive power reserve requirement of the wind farm by taking into account the reactive power margin boundary, transient overvoltage safety threshold and admittance matrix steady-state constraints.

2. The wind power reactive power reserve setting method based on high-voltage ride-through control according to claim 1, characterized in that: In step S1, based on the relevant transient characteristic parameters of the wind farm in the system, including the overall magnetic flux leakage ratio of the wind farm, stator transient reactance, relaxation time constant of the DC component of the stator and rotor windings, excitation coupling inductance, stator inductance and leakage inductance, and rotor inductance and leakage inductance, an expression for the short-circuit current after a wind farm fault is constructed. Then, the short-circuit current expression is simplified based on the fact that the fault time is zero, resulting in an expression for calculating the inherent impedance of the grid side of the wind farm as a whole.

3. The wind power reactive power reserve setting method based on high-voltage ride-through control according to claim 2, characterized in that: In step S2, the method for calculating the impedance of the high-voltage ride-through control loop in the wind farm is as follows: First, the wind farm is set up. shaft current Equal to the entire wind farm Shaft stator current The reactive current of the wind farm under different states is obtained as follows: (1) In the formula: This refers to the output voltage of the wind farm. and These are the high-voltage ride-through control parameters. This represents the reactive current prior to the fault. This is the nominal voltage of the wind farm. For the active power output of the wind farm For the power angle of the wind farm, The voltage threshold for whether a wind farm can undergo high-voltage ride-through; Next, combining the voltage regulation mechanism of wind power and formula (1), the high-voltage ride-through control of the wind farm is converted into impedance as shown in formula (2). The voltage regulation mechanism of wind power is: when the system encounters a fault leading to More than 1.1 times At that time, wind power needs to be controlled By changing its reactive power output, voltage regulation can be achieved. (2) (3) In the formula: The equivalent impedance for high-voltage ride-through control in wind farms; and These represent the wind farm outlet voltage before the fault and the wind farm outlet voltage increment after the fault, respectively. Then, the interaction between the reactive power regulation of wind power and the voltage change at the grid connection point is analyzed to determine the change in reactive power output of the wind farm during high-voltage ride-through. Normalized representation: (4) In the formula, , , , , , They are respectively , , , , , The normalized value; Finally, the equivalent impedance for high-voltage ride-through control in wind farms is derived. Normalized representation: (5) In the formula, , They are respectively , The normalized value.

4. The wind power reactive power reserve setting method based on high-voltage ride-through control according to claim 3, characterized in that: In step S3, the method for calculating the peak value of the wind farm outlet voltage after the fault is as follows: First, obtain the normalized value of the network admittance matrix from the system power flow results. Its expression is: (6) Where n represents the number of system nodes, and f represents the node where the converter station is located; Represents a node With nodes The normalized value of the mutual admittance between them. Represents a node The normalized value of the auto-admittance, ; Then, the corrected self-admittance expressions for the synchronous generator units and wind farms in the system are determined respectively; 1) The self-admittance of the synchronous generator is corrected based on the normalized value of the subtransient impedance of the synchronous generator, as shown in the following formula: (7) In the formula: This indicates the node where the synchronous generator unit is located. and The first The normalized values ​​of the self-admittance and modified self-admittance of each node. and These are the base capacity and normalized subtransient reactance of the synchronous generator unit, respectively. This serves as the baseline value for system capacity. 2) The self-admittance of the wind farm is corrected based on the inherent impedance of the grid side of the wind farm as a whole and the equivalent impedance of the high-voltage ride-through control link of the wind farm, as shown in the following formula: (8) In the formula: Indicates the node where the wind farm is located. and The first The normalized values ​​of the self-admittance and modified self-admittance of each node. This is the baseline capacity located in the wind farm; The magnetic flux leakage ratio is located throughout the wind farm. This represents the normalized value of the stator transient reactance for the entire wind farm. This is the normalized value of the converted impedance for high-voltage ride-through control in the wind farm; Next, based on the DC blocking condition being approximated as injecting an equivalent current source at the fault location, the relationship between the current and voltage change vectors of the converter station after the fault is determined, and the corrected network admittance matrix is ​​constructed. (9) (10) In the formula: , and These are the short-circuit capacity of the converter station nodes, and the normalized values ​​of reactive power and voltage changes caused by DC blocking at the converter station, respectively. and This is a normalized vector of the changes in current and voltage at each node after a fault. According to The corrected network admittance matrix; Finally, based on the corrected network admittance matrix, the expression for the voltage change at each node in the network is determined: (11) In the formula, This is the normalized value of the current change at the converter station node after the fault. The corrected self-admittance for converter station nodes; Simplifying equation (11) yields: (12) In the formula: The corrected self-impedance of node f in the system. This is the corrected mutual impedance between node n and node f in the system; Based on this, the normalized value of the voltage change of any wind farm in the network is derived as follows: (13) In the formula: For nodes in the system Corrected mutual impedance between node f; Combining equations (3) and (13), the normalized value of the peak value of the wind farm outlet voltage after the fault is obtained. Characterized as: (14) 。 5. The wind power reactive power reserve setting method based on high-voltage ride-through control according to claim 4, characterized in that: In step S4, a model is established with the goal of minimizing the total reactive power reserve requirement provided by the high voltage ride-through control of the wind farm under DC blocking conditions, taking into account the reactive power margin boundary, the transient overvoltage safety threshold and the steady-state constraint of the admittance matrix. The reactive power reserve requirement of the wind farm is then quantitatively tuned. (15) In the formula: Represents a collection of wind farms; and These represent the normalized values ​​of reactive power output and reactive power output change during the high-voltage ride-through process of the wind farm, respectively. This represents the reactive power reserve requirement of a normalized wind farm. This is the upper limit for reactive power in wind farms; This is the normalized threshold for the wind farm's outlet voltage. For the corrected network impedance matrix; It is an identity matrix.

6. The wind power reactive power reserve setting method based on high-voltage ride-through control according to claim 5, characterized in that: In step S4, the steady-state constraint condition of the admittance matrix is ​​replaced by the following constraint: (16) In the formula: and Represent matrices respectively and The List.

7. A wind power reactive power reserve setting device based on high-voltage ride-through control, comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: The processor executes the computer program to implement the wind power reactive power reserve setting method based on high voltage ride-through control as described in any one of claims 1-6.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by the processor, it implements the wind power reactive power reserve setting method based on high voltage ride-through control as described in any one of claims 1-6.

9. A computer program product, comprising a computer program, characterized in that: When executed by a processor, the computer program implements the wind power reactive power reserve setting method based on high voltage ride-through control as described in any one of claims 1-6.

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