New energy converter voltage ride through key control parameter identification method

Abstract

The invention discloses a new energy converter voltage ride-through key control parameter identification method, and relates to the technical field of voltage ride-through key control parameter identification. Based on a control performance expression in a voltage instability process, determining a voltage control parameter range, and constructing a voltage instability fault set; calculating sensitivity factors of the voltage control parameters to voltage instability under typical fault conditions, scanning typical working conditions in a voltage instability fault set, and generating a voltage sensitivity factor matrix of the voltage control parameters; and selecting the maximum value of the element corresponding to each voltage control parameter in the voltage sensitivity factor matrix as a typical voltage sensitivity factor, and carrying out descending order arrangement to identify the key control parameter. According to the method, the stability influence of the voltage ride-through control parameters of the new energy converter on the power grid is scientifically quantified, the key control parameters are identified in a mode of constructing the fault scene set, and rapid development of a wind, light and fire energy base is efficiently assisted.

Description

Technical Field

[0001] The present invention relates to the technical field of identification of key control parameters for voltage ride-through, and particularly to a method for identifying key control parameters for voltage ride-through of a new energy converter. Background Art

[0002] In the process of promoting the construction of a new power system, the wind-solar-thermal bundled DC transmission system, as an important power transmission method, has been increasingly emphasized. This system combines wind energy, solar energy and thermal power, and uses high-voltage DC transmission technology to achieve efficient utilization of resources and long-distance power transmission. However, with the continuous increase in the proportion of renewable energy, especially in areas rich in wind and solar resources, local faults in energy bases or DC commutation failures often occur, resulting in system voltage instability and then triggering a large number of new energy converters to trip off the network. This not only affects the safe supply of electricity, but also poses higher requirements for the stability of the power system.

[0003] Therefore, scientifically identifying and optimizing the key control parameters required by new energy converters during voltage instability has become an important research topic. For this reason, we have designed a method for identifying key control parameters for voltage ride-through of new energy converters to solve the above problems. Summary of the Invention

[0004] The purpose of the present invention is to solve the problems of system voltage instability caused by local faults in new energy bases or DC commutation failures and the phenomenon of new energy converters tripping off the network in the prior art, and to propose a method for identifying key control parameters for voltage ride-through of new energy converters. This method not only scientifically quantifies the influence of the control parameters of new energy converters on grid stability, but also provides strong support for the rapid development of wind-solar-thermal energy bases, promotes the efficient utilization of renewable energy and the overall optimization of the power system.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions: A method for identifying key control parameters for voltage ride-through of a new energy converter, comprising the following steps: Step S1, based on the control performance expression during the voltage instability process of photovoltaic and wind power converters, determine the voltage control parameters of the converter that affect voltage stability, and construct a voltage instability fault set caused by local faults in the energy base and DC system commutation failures; Step S2, calculate the sensitivity factor of each converter voltage control parameter to voltage instability under typical fault conditions in the voltage instability fault set, scan each typical working condition in the voltage instability fault set, and generate a voltage sensitivity factor matrix of each converter voltage control parameter; In step S3, select the maximum value of the elements corresponding to the voltage control parameters of each converter in the voltage sensitivity factor matrix as the typical voltage sensitivity factor, and arrange all the typical voltage sensitivity factors in descending order to identify the key control parameters.

[0006] Further preferably, in step S1, by adjusting the active current control command and reactive current control command of the converter during the voltage ride-through process of the wind turbine to change the output power, the control performance expression during the voltage instability process based on the photovoltaic and wind power converters is determined as follows: The active current control command of the converter during low voltage ride-through and high voltage ride-through 、 The expression is: ; In the above formula, and are the active current calculation coefficients for low voltage ride-through in the active current control command expression, and are the active current calculation coefficients for high voltage ride-through in the active current control command expression; is the grid-connected voltage; is the initial value of the active current; 、 are the set values of the active current for low voltage ride-through and high voltage ride-through respectively; The reactive current control command of the active current control command of the converter during low voltage ride-through and high voltage ride-through 、 The expression is: ; In the above formula, and are the active current calculation coefficients for low voltage ride-through in the reactive current control command expression, and are the active current calculation coefficients for high voltage ride-through in the reactive current control command expression; 0.9 and 1.1 are the voltage thresholds for entering low voltage ride-through and high voltage ride-through respectively; is the initial value of the reactive current; 、 are the set values of the reactive current for low voltage ride-through and high voltage ride-through; The active current command during the low voltage ride-through and high voltage ride-through control processes of the photovoltaic inverter 、 and the reactive current command 、 The expression is: ; ; In the above formula, represents the active current command during the low-voltage ride-through control process of the photovoltaic inverter; represents the reactive current command during the low-voltage ride-through control process of the photovoltaic inverter; min represents taking the smaller value between the two; represents the grid-connected point voltage of the photovoltaic cluster detected during the low-voltage dip process; represents the active power reference value of the photovoltaic cluster before the low-voltage dip; represents the maximum current output by the photovoltaic inverter; represents the correction slope value during the low-voltage ride-through recovery process of the photovoltaic inverter; represents the reactive current command value when the low voltage of the photovoltaic inverter is at the lowest value, represents the active current command during the high-voltage ride-through control process of the photovoltaic inverter; represents the reactive current command during the high-voltage ride-through control process of the photovoltaic inverter; represents the grid voltage step-up amplitude; represents the detected grid-connected point voltage when the reactive current command value for the high-voltage ride-through of the photovoltaic inverter, represents the detected grid-connected point voltage when the correction amount of the reactive current command value for the high-voltage ride-through of the photovoltaic inverter; Based on the expressions in the wind power and photovoltaic converters that affect the voltage ride-through control performance , , , , , , , , , , , , , , , , , , the setting of the numerical values of these voltage control parameters affects the voltage ride-through control performance of each converter. In addition, the active current recovery speed and the reactive current recovery speed also affect the voltage ride-through control performance of the wind turbine. The voltage control parameters that affect the voltage ride-through control performance of each converter and the wind turbine are used as the candidates for identifying the key voltage ride-through control parameters, and are determined as the voltage control parameters that affect the voltage stability of the converter.

[0007] Further preferably, in step S1, a voltage instability fault set caused by local faults in the energy base and commutation failures in the DC system is constructed. The voltage instability fault set Ψ caused by local faults in the energy base is expressed as: ; The voltage instability fault set caused by commutation failures in the DC external transmission system can be expressed as: ; In the above formula, is the th fault condition in the voltage instability fault set Ψ caused by local faults in the energy base; is the th fault condition in the voltage instability fault set caused by commutation failures in the DC external transmission system; is the total number of fault conditions in the voltage instability fault set caused by local faults in the energy base; is the total number of fault conditions in the voltage instability fault set caused by commutation failures in the DC external transmission system.

[0008] Further preferably, in step S2, the sensitivity factor of each converter voltage control parameter to voltage instability under typical fault conditions in the voltage instability fault set is calculated. When analyzing the sensitivity of a certain target voltage control parameter to voltage control performance, other voltage control parameters are maintained at typical values under a typical fault condition, and the target voltage control parameter is increased from the minimum value to its corresponding maximum value at an increase rate of 10%. The voltage fluctuation values of the new energy units with different target voltage control parameter values are recorded. The set of voltage fluctuation values of the new energy units corresponding to different numerical conditions of the target voltage control parameter is: ; In the formula, is the voltage fluctuation value of the new energy unit under the th numerical condition of the target voltage control parameter under a certain typical fault condition; Select the maximum value of all elements in the set of voltage fluctuation values as the sensitivity factor of voltage instability at the th fault condition for identifying the candidate quantity of the key control parameter during the voltage crossing process of the th converter: .

[0009] Further preferably, in step S2, combining the calculated th candidate quantity for identifying the key control parameter of the new energy converter voltage crossing The sensitivity factor of voltage instability under a single fault condition is used to scan each typical condition in the constructed voltage instability fault set, generating a voltage sensitivity factor matrix of voltage control parameters, which are candidate quantities for identifying key control parameters during voltage ride-through in each converter. : ; In the formula, is the sensitivity factor of voltage instability under the -th fault condition for the candidate quantity in identifying the key control parameter during the voltage ride-through of the -th converter voltage; is the total number of all fault conditions in the voltage instability fault set of the wind-solar-thermal energy base through the HVDC transmission system.

[0010] Further preferably, in step S3, the maximum value of the elements corresponding to the voltage control parameters of each converter in the voltage sensitivity factor matrix is selected as the typical voltage sensitivity factor of the parameter, and its expression is: ; In the formula, is the typical voltage sensitivity factor of the -th parameter; is the element value of the -th row in the voltage sensitivity factor matrix ; The set of typical voltage sensitivity factors containing all voltage control parameters is sorted in descending order to identify the key control parameters. The set of typical voltage sensitivity factors has the expression: ; In the formula, is the typical voltage sensitivity factor of the voltage control parameter. All elements in the set of typical voltage sensitivity factors are sorted in descending order, and the voltage control parameters corresponding to the first 5 elements are selected as the key control parameters for voltage ride-through of the new energy converter identified.

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows: Based on the control performance expression during the voltage instability process, the present invention determines the range of voltage control parameters affecting voltage control, constructs a voltage instability fault set; calculates the sensitivity factor of voltage control parameters to voltage instability, scans each typical working condition in the voltage instability fault set, and generates a voltage sensitivity factor matrix of voltage control parameters; selects the maximum value of the elements corresponding to each voltage control parameter in the voltage sensitivity factor matrix as the typical voltage sensitivity factor, and arranges them in descending order to identify the key control parameters. By the above means, the present invention scientifically quantifies the stable influence of the voltage ride-through control parameters of new energy converters on the power grid, identifies the key control parameters by constructing a fault scenario set, reduces the risk of system voltage instability caused by local faults in new energy bases or DC commutation failures and the phenomenon of new energy converters tripping off the grid, improves the power supply capacity and security of the power grid, ensures the stability of the power system, promotes the efficient utilization of renewable energy and the overall optimization of the power system, and efficiently contributes to the rapid development of wind-solar-thermal energy bases. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 FIG. is a flowchart of the steps of a method for identifying key voltage ride-through control parameters of a new energy converter proposed by the present invention; Figure 2 FIG. is a schematic diagram of the topological structure of a wind-solar-thermal bundled DC transmission system in an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0013] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0014] Transmitting wind-solar-thermal power through a high-voltage DC transmission system is an important way to promote the construction of a new power system. Due to local faults in energy bases or DC commutation failures, system voltage instability problems may occur, and a large number of new energy converters in wind-solar-thermal energy bases may trip off the grid. Therefore, a method for identifying key voltage ride-through control parameters of new energy converters is proposed.

[0015] As Figure 1 shown, the method for identifying key voltage ride-through control parameters of the new energy converter includes the following steps: Step S1: Based on the control performance expression during the voltage instability process of photovoltaic and wind power converters, determine the range of voltage control parameters that affect the voltage stability of the converter, and construct a voltage instability fault set caused by local faults in the energy base and DC system commutation failures.

[0016] Specifically, the operation is as follows: The output power can be changed by adjusting the active current control command and reactive current control command of the converter during the voltage ride-through process of the wind turbine. The control performance expression during the voltage instability process based on the photovoltaic and wind power converters is determined as follows: The active current control command of the converter during low voltage ride-through and high voltage ride-through 、 The expression is: ; In the above formula, and Are the active current calculation coefficients for low voltage ride-through in the active current control command expression, and Are the active current calculation coefficients for high voltage ride-through in the active current control command expression; Is the grid-connected voltage; Is the initial value of the active current; 、 Are the set values of the active current for low voltage ride-through and high voltage ride-through respectively.

[0017] The reactive current control command of the active current control command of the converter during low voltage ride-through and high voltage ride-through 、 The expression is: ; In the above formula, and Are the active current calculation coefficients for low voltage ride-through in the reactive current control command expression, and Are the active current calculation coefficients for high voltage ride-through in the reactive current control command expression; 0.9 and 1.1 are the voltage thresholds for entering low voltage ride-through and high voltage ride-through respectively; Is the initial value of the reactive current; 、 Are the set values of the reactive current for low voltage ride-through and high voltage ride-through respectively.

[0018] The active current command expression and reactive current command in the photovoltaic converter will affect the voltage transient control performance of the converter. Therefore, in this embodiment, the active current commands 、 And reactive current commands 、 During the low voltage ride-through and high voltage ride-through control processes of the photovoltaic inverter are considered, and their expressions are: ; ; In the above formula, Represents the active current command during the low-voltage ride-through control of a PV inverter; Represents the reactive current command during the low-voltage ride-through control of a PV inverter; min represents taking the smaller value between the two; Represents the grid-connected point voltage of the PV cluster detected during the low-voltage dip process; Represents the active power reference value of the PV cluster before the low-voltage dip; Represents the maximum current output by the PV inverter; Represents the correction slope value during the low-voltage ride-through recovery process of the PV inverter; Represents the reactive current command value when the PV inverter is at the lowest voltage in the low-voltage state, Represents the active current command during the high-voltage ride-through control of the PV inverter; Represents the reactive current command during the high-voltage ride-through control of the PV inverter; Represents the amplitude of the grid voltage step-up; Represents the detected grid-connected point voltage When, the reactive current command value for the high-voltage ride-through of the PV inverter; Represents the detected grid-connected point voltage When, the correction amount of the reactive current command value for the high-voltage ride-through of the PV inverter; Based on the expressions in wind power and PV converters that affect the voltage ride-through control performance 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 , the setting sizes of these voltage control parameter values directly affect the voltage ride-through control performance of each converter. In addition, the active current recovery speed and the reactive current recovery speed of the voltage control parameters also affect the voltage ride-through control performance of the wind turbine. These 18 voltage control parameters are used as the candidates for identifying the key voltage control parameters for voltage ride-through and are determined as the voltage control parameters that affect the voltage stability of the converter.

[0019] Analyze the mechanism of voltage instability in the large-scale integrated wind-solar-thermal power base transmitted by DC. The topology of the large-scale integrated wind-solar-thermal power base transmitted by DC is as Figure 2 shown.Figure 2 In and are the active power and reactive power output of the conventional power source in the energy base with integrated wind, light and thermal power transmitted bundled; and are the active power and reactive power output of the photovoltaic cluster in the energy base with integrated wind, light and thermal power transmitted bundled; and are the active power and reactive power output of the wind farm group in the energy base with integrated wind, light and thermal power transmitted bundled; is the sending-end AC / DC bus voltage; is the reactive power output of the reactive power compensation device configured at the rectifier station of the DC transmission system; and are the active power and reactive power transmitted by the DC transmission line, represents the reactive power compensation coefficient of the conventional power source output in the energy base with integrated wind, light and thermal power transmitted bundled.

[0020] Based on the above analysis of the voltage instability caused by the integrated wind, light and thermal power energy base through the DC external transmission system, this embodiment constructs a voltage instability fault set caused by local faults in the energy base and commutation failures in the DC system. Among them, the voltage instability fault set Ψ caused by local faults in the energy base is expressed as: ; The voltage instability fault set caused by commutation failures in the DC external transmission system can be expressed as: ; In the above formula, is the th fault condition in the voltage instability fault set Ψ caused by local faults in the energy base; is the th fault condition in the voltage instability fault set caused by commutation failures in the DC external transmission system; is the total number of fault conditions in the voltage instability fault set caused by local faults in the energy base; is the total number of fault conditions in the voltage instability fault set caused by commutation failures in the DC external transmission system.

[0021] Step S2, calculate the sensitivity factors of the voltage control parameters of each converter to voltage instability under typical fault conditions in the voltage instability fault set, scan each typical condition in the constructed voltage instability fault set, and generate a voltage sensitivity factor matrix of the voltage control parameters of each new energy converter. The detailed operation process is as follows: Calculate the sensitivity factors of the voltage control parameters of each converter to voltage instability under typical fault conditions for voltage instability faults. When analyzing the sensitivity of a certain target voltage control parameter to voltage control performance, under a typical fault condition, keep other voltage control parameters (the remaining 17 voltage control parameters) at typical values, and increase the target voltage control parameter from the minimum value to its corresponding maximum value in increments of 10%. Record the voltage fluctuation values of the new energy units with different target voltage control parameter values (a total of 11 sets of data values). The set of voltage fluctuation values of the new energy units corresponding to different values of the target voltage control parameter is: ; In the formula, is the voltage fluctuation value of the new energy unit under the th numerical condition of the target voltage control parameter under a certain typical fault condition.

[0022] To calculate the sensitivity factors of the control parameters of each converter to voltage instability under typical fault conditions, the maximum value of all elements in the set of voltage fluctuation values can be selected as the candidate quantity for identifying the key control parameters during the voltage crossing process of the th converter, which is the sensitivity factor of voltage instability under the th fault condition , ; Combined with the calculated sensitivity factor of voltage instability under the th candidate quantity for identifying the key control parameters during the voltage crossing process of the new energy converter, scan each typical condition in the constructed voltage instability fault set, and generate a voltage sensitivity factor matrix of 18 voltage control parameters that are candidate quantities for identifying the key control parameters during the voltage crossing process in each converter : : ; In the formula, is the sensitivity factor of voltage instability under the th candidate quantity for identifying the key control parameters during the voltage crossing process of the th converter; is the total number of all fault conditions in the voltage instability fault set of the energy base of the wind-solar-thermal energy base through the DC transmission system, including the total number of fault conditions in the voltage instability fault set caused by local faults of the energy base and the total number of fault conditions in the voltage instability fault set caused by commutation failures in the DC external transmission system .

[0023] In step S3, select the maximum value of the elements corresponding to the voltage control parameters of each new energy converter in the voltage sensitivity factor matrix as the typical voltage sensitivity factor of the voltage control parameter, arrange the typical voltage sensitivity factors of all voltage control parameters in descending order, and identify the key control parameters.

[0024] Select the maximum value of the elements corresponding to the voltage control parameters of each converter in the voltage sensitivity factor matrix as the typical voltage sensitivity factor of the parameter, and its expression is: ; In the formula, is the typical voltage sensitivity factor of the th parameter; is the voltage sensitivity factor matrix of 18 voltage control parameters that are candidate quantities for identifying the key control parameters for voltage ride-through in the generated new energy converters in the th row of the element value; Arrange the set of typical voltage sensitivity factors including all voltage control parameters in descending order to identify the key control parameters. The set of typical voltage sensitivity factors expression is: ; In the formula, is the typical voltage sensitivity factor of the voltage control parameter; arrange all the elements in the set of typical voltage sensitivity factors in descending order, and select the voltage control parameters corresponding to the first 5 elements as the identified key control parameters for voltage ride-through of the new energy converter.

[0025] The method for identifying key control parameters for voltage ride-through based on the control performance expression of the present invention weakens the influence of the voltage ride-through characteristics of new energy converters on the stability of the power grid. This method first establishes a voltage instability fault set including various fault scenarios, generates a voltage sensitivity factor matrix by analyzing the sensitivity of the control parameters of photovoltaic and wind power converters to voltage stability under different fault conditions. By selecting the maximum value of each control parameter in the matrix as the typical sensitivity factor and sorting, the key control parameters with the greatest influence on voltage stability can be effectively identified. This research not only scientifically quantifies the influence of the control parameters of new energy converters on the stability of the power grid, but also provides strong support for the rapid development of wind-solar-thermal energy bases, promotes the efficient utilization of renewable energy and the overall optimization of the power system.

[0026] As described above, it is only the preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, making equivalent substitutions or changes should be covered within the protection scope of the present invention.

Claims

1. A method for identifying key control parameters of voltage ride-through of a new energy converter, characterized in that: The following steps are involved: Step S1, based on the control performance expression of the voltage instability process of photovoltaic and wind power converters, determine the voltage control parameters of the converter that affect the voltage stability, and construct a voltage instability fault set including local faults of the energy base and commutation failure of the DC system; Step S2, calculating the sensitivity factor of each converter voltage control parameter to voltage instability under typical fault conditions of the voltage instability fault concentration, scanning each typical working condition of the voltage instability fault concentration, and generating a voltage sensitivity factor matrix of each converter voltage control parameter; In step S3, the maximum value of the element corresponding to the voltage control parameter of each converter in the voltage sensitivity factor matrix is ​​selected as the typical voltage sensitivity factor, all typical voltage sensitivity factors are arranged in descending order, and the key control parameters are identified.

2. A method for identifying key control parameters of voltage ride through of a new energy converter according to claim 1, characterized in that: In step S1, the output power is changed by adjusting the active current control command and reactive current control command of the converter during the voltage ride-through process of the wind turbine, and the control performance expression during the voltage instability process based on photovoltaic and wind power converters is determined as follows: Converter active current control instructions during low voltage ride-through and high voltage ride-through , The expression is: ； In the above formula, and is the active current calculation coefficient of low voltage ride through in the active current control instruction expression, and The active current calculation coefficient of the high voltage ride through of the active current control instruction expression; is the grid-related voltage; is the initial value of active current; , They are respectively the active current setting values ​​for low voltage ride through and high voltage ride through; Reactive current control instructions of converter active current control instructions during low voltage ride-through and high voltage ride-through , The expression is: ； In the above formula, and is the active current calculation coefficient of low voltage ride through in the reactive current control instruction expression, and is the active current calculation coefficient of the high voltage ride through of the reactive current control instruction expression; 0.9 and 1.1 are the voltage thresholds for entering the low voltage ride through and high voltage ride through respectively; is the initial value of reactive current; , They are the reactive current setting values ​​for low voltage ride through and high voltage ride through respectively; Active current command during low voltage ride through and high voltage ride through control of photovoltaic inverter , and reactive current command , The expression is: ； ； In the above formula, Indicates the active current command during the low voltage ride-through control process of the photovoltaic inverter; Indicates the reactive current command during the low voltage ride through control process of the photovoltaic inverter; min means taking the smaller value between the two; Indicates the voltage of the photovoltaic cluster grid connection point detected during the low voltage drop process; Indicates the active power reference value of the PV cluster before the low voltage drops; Indicates the maximum current output by the photovoltaic inverter; Indicates the correction slope value of the low voltage ride-through recovery process of the PV inverter; Indicates the reactive current command value when the photovoltaic inverter low voltage is at the lowest value. Indicates the active current command during the high voltage ride through control process of the photovoltaic inverter; Indicates the reactive current command during the high voltage ride through control process of the photovoltaic inverter; Indicates the sudden rise of grid voltage; Indicates the detected grid connection point voltage When the reactive current command value of the photovoltaic inverter high voltage ride through is Indicates the detected grid connection point voltage When , the correction value of the reactive current command value of the PV inverter high voltage ride through; Based on the expression affecting the voltage ride-through control performance in wind power and photovoltaic converters , , , , , , , , , , , , , , , , , The setting affects the voltage ride-through control performance of each converter. In addition, the active current recovery speed and reactive current recovery speed It also affects the voltage ride-through control performance of the wind turbine. The voltage control parameters that affect the voltage ride-through control performance of the converter and the wind turbine are used as candidates for identifying key control parameters of voltage ride-through and are determined as voltage control parameters that affect the voltage stability of the converter.

3. The method for identifying key control parameters of voltage ride through of a new energy converter according to claim 1 is characterized in that: In step S1, a voltage instability fault set caused by local faults of energy bases and commutation failures of DC systems is constructed. The voltage instability fault set Ψ caused by local faults of energy bases is expressed as: ； Voltage instability fault caused by commutation failure in DC transmission system It is expressed as: ； In the above formula, The voltage instability fault cluster caused by local faults in the energy base is Fault conditions; The voltage instability fault caused by commutation failure in the DC transmission system is The Fault conditions; The total number of fault conditions of the voltage instability fault set caused by local faults of the energy base; is the total number of fault conditions of the voltage instability fault set caused by commutation failure of the DC transmission system.

4. The method for identifying key control parameters of voltage ride through of a new energy converter according to claim 1, characterized in that: In step S2, the sensitivity factors of the voltage control parameters of each converter to the voltage instability under the typical fault conditions are calculated. When analyzing the sensitivity of a certain target voltage control parameter to the voltage control performance, other voltage control parameters are maintained at typical values ​​under a typical fault condition, and the target voltage control parameter is increased from the minimum value to its corresponding maximum value by 10%. The voltage fluctuation values ​​of the new energy units with different target voltage control parameter values ​​are recorded. The voltage fluctuation value set of the new energy units corresponding to different target voltage control parameter values ​​is for: ； In the formula, is the target voltage control parameter under a typical fault condition. Voltage fluctuation value of new energy units under numerical conditions; Select the voltage fluctuation value set The maximum value of all elements in The first candidate quantity for key control parameter identification during the voltage ride-through of a converter Sensitivity factors of voltage instability under fault conditions : 。 5. A method for identifying key control parameters of voltage ride through of a new energy converter according to claim 4, characterized in that: Combined with the calculation The first candidate quantity for the identification of key control parameters of voltage ride-through of a new energy converter The sensitivity factor of voltage instability under each fault condition is calculated by scanning each typical condition in the constructed voltage instability fault set, and a voltage sensitivity factor matrix of the voltage control parameters to be selected as the key control parameter identification of voltage ride-through in each converter is generated. : ； In the formula, For the The first candidate quantity for key control parameter identification during the voltage ride-through of a converter The sensitivity factor of voltage instability under a fault condition; F is the number of all fault conditions in the energy base voltage instability fault set of the constructed wind, solar and thermal energy base through the DC transmission system.

6. The method for identifying key control parameters of voltage ride through of a new energy converter according to claim 1, characterized in that: In step S3, the maximum value of the element corresponding to the voltage control parameter of each converter in the voltage sensitivity factor matrix is ​​selected as the typical voltage sensitivity factor of the parameter, and its expression is for: ; In the formula, For the Typical voltage sensitivity factors for each parameter; is the voltage sensitivity factor matrix Middle The element value of the row; The typical voltage sensitivity factor set containing all voltage control parameters is sorted in descending order to identify the key control parameters. The typical voltage sensitivity factor set The expression is: ； In the formula, is the typical voltage sensitivity factor of the voltage control parameter, and the typical voltage sensitivity factor is set All elements in are arranged in descending order, and the voltage control parameters corresponding to the first 5 elements are selected as the key control parameters of the identified new energy converter voltage ride-through.

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