A grid-side high-voltage protection system for a wind turbine converter

Abstract

The present invention discloses a grid-side high-voltage protection system for a wind turbine converter, comprising: an acquisition module for acquiring historical voltage data of the grid side of the converter and the rated voltage of the converter; a determination module for determining the voltage ride-through level of the converter according to the historical voltage data and determining the specifications of the relevant components of the converter according to the voltage ride-through level, and the relevant components of the converter include a chopper assembly; a detection module for detecting the real-time grid voltage and the real-time bus voltage of the grid side of the converter; a processing module for setting a working state instruction for the chopper assembly according to the real-time grid voltage and the real-time bus voltage; and a control module for controlling the chopper assembly according to the working state instruction set by the processing module to protect the converter. By determining the specifications of the relevant components of the converter and controlling the chopper assembly through the historical voltage data, the real-time grid voltage and the real-time bus voltage, the protection of the converter during high-voltage ride-through is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of converters, and particularly to a grid-side high-voltage protection system for a wind turbine converter. Background Art

[0002] Wind energy is a clean and pollution-free renewable energy source and one of the green energy sources advocated by the country. Wind power generation refers to converting the kinetic energy of wind into electrical energy. A device that converts the wind energy in nature into electrical energy. The wind energy in nature drives the blades of a wind turbine generator set to absorb the wind energy, and the blades drive the generator to convert the wind energy into electrical energy. Since the national power grid has regulations on the frequency and phase of the grid-connected electrical energy, and the generator cannot meet the requirements for direct grid connection of the electrical energy, corresponding electrical equipment must be added between the generator and the power grid, that is, the converter realizes converting the electrical energy generated by the generator into the frequency, phase, etc. required by the power grid and can perform active and reactive power control.

[0003] However, when a high voltage appears in the power grid, the grid-side output power of the converter is suppressed, resulting in an increase in the DC bus voltage of the converter. When the bus voltage exceeds the limit voltage of the converter, it may cause damage to the converter, batch shutdown of wind turbine generator sets, and impact on the power grid, thus causing economic losses. Summary of the Invention

[0004] The purpose of the present invention is to provide a grid-side high-voltage protection system for a wind turbine converter to solve the problem that when the power grid undergoes high-voltage ride-through, the converter trips due to the instantaneous increase in the bus voltage.

[0005] The present invention provides a grid-side high-voltage protection system for a wind turbine converter, including:

[0006] An acquisition module, which is used to acquire the historical voltage data of the grid side of the converter and the rated voltage of the converter;

[0007] A determination module, which is used to determine the voltage ride-through level of the converter according to the historical voltage data and determine the specifications of the relevant components of the converter according to the voltage ride-through level. The relevant components of the converter include the chopper assembly;

[0008] A detection module, which is used to detect the real-time grid voltage and the real-time bus voltage of the grid side of the converter;

[0009] A processing module, which is used to set the working state instruction of the chopper assembly according to the real-time grid voltage and the real-time bus voltage;

[0010] A control module, which is used to control the chopper assembly according to the working state instruction set by the processing module to protect the converter.

[0011] In some embodiments of the present application, the historical voltage data includes the maximum grid voltage and the duration of maintaining the maximum grid voltage.

[0012] In some embodiments of the present application, the determining module determines the voltage ride-through level of the converter according to the historical voltage data, including:

[0013] Receiving the historical voltage data of the grid side of the converter and the rated voltage of the converter obtained by the obtaining module;

[0014] Determining the voltage ratio between the maximum grid voltage and the rated voltage, and determining the voltage ride-through level of the converter according to the voltage ratio;

[0015] Correcting the voltage ride-through level of the converter according to the duration of maintaining the maximum grid voltage to obtain the final voltage ride-through level of the converter.

[0016] In some embodiments of the present application, the components related to the converter further include a circuit breaker, a filter capacitor, a filter reactor, a grid-connected switch, and an auxiliary transformer.

[0017] In some embodiments of the present application, a preset voltage ratio matrix V0 and a preset voltage ride-through level matrix L0 are set in the determining module. For the preset voltage ratio matrix V0, V0(V1, V2, V3, V4) is set, where V1 is the first preset voltage ratio, V2 is the second preset voltage ratio, V3 is the third preset voltage ratio, V4 is the fourth preset voltage ratio, and V1 < V2 < V3 < V4;

[0018] For the preset voltage ride-through level matrix L0, L0(L1, L2, L3, L4) is set, where L1 is the first preset voltage ride-through level; L2 is the second preset voltage ride-through level; L3 is the third preset voltage ride-through level; L4 is the fourth preset voltage ride-through level, and L1 < L2 < L3 < L4;

[0019] The determining module is used to obtain the maximum grid voltage of the grid side of the converter and the rated voltage of the converter, calculate the voltage ratio v between the maximum grid voltage and the rated voltage, and set the voltage ride-through level of the converter according to the relationship between the voltage ratio v and each preset voltage ratio;

[0020] When v < V1, set the first preset voltage ride-through level L1 as the voltage ride-through level of the converter;

[0021] When V1 ≤ v < V2, set the second preset voltage ride-through level L2 as the voltage ride-through level of the converter;

[0022] When V2 ≤ v < V3, set the third preset voltage ride-through level L3 as the voltage ride-through level of the converter;

[0023] When V3 ≤ v < V4, set the fourth preset voltage ride-through level L4 as the voltage ride-through level of the converter.

[0024] In some embodiments of the present application, a preset duration matrix T0 is set in the determination module. For the preset duration matrix T0, set T0(T1, T2, T3, T4), where T1 is the first preset duration, T2 is the second preset duration, T3 is the third preset duration, T4 is the first preset duration, and T1 < T2 < T3 < T4;

[0025] After determining the i-th preset voltage ride-through level Li as the voltage ride-through level of the converter according to the voltage ratio v, where i = 1, 2, 3, 4 at this time; obtain the duration t of maintaining the maximum value of the grid voltage, and correct the i-th preset voltage ride-through level Li according to the relationship between the duration t of maintaining the maximum value of the grid voltage and each preset duration to obtain the final voltage ride-through level of the converter;

[0026] When t < T1, then use the i-th preset voltage ride-through level Li as the final voltage ride-through level of the converter;

[0027] When T1 ≤ t < T2, then increase the i-th preset voltage ride-through level Li by one level as the final voltage ride-through level of the converter. If it is the fourth preset voltage ride-through level L4 at this time, then directly use the fourth preset voltage ride-through level L4 as the final voltage ride-through level of the converter;

[0028] When T2 ≤ t < T3, then increase the i-th preset voltage ride-through level Li by two levels as the final voltage ride-through level of the converter. If it is the fourth preset voltage ride-through level L4 at this time, then directly use the fourth preset voltage ride-through level L4 as the final voltage ride-through level of the converter;

[0029] When T3 ≤ t < T4, then increase the i-th preset voltage ride-through level Li by three levels as the final voltage ride-through level of the converter. If it is the fourth preset voltage ride-through level L4 at this time, then directly use the fourth preset voltage ride-through level L4 as the final voltage ride-through level of the converter.

[0030] In some embodiments of the present application, the processing module sets the working state instruction of the chopper component according to the real-time grid voltage and the real-time bus voltage, including:

[0031] Determine the effective value of the grid voltage according to the real-time grid voltage;

[0032] Compare the effective value of the grid voltage with the set value of the grid voltage, and determine the operating state of the converter according to the comparison result;

[0033] Based on the operating state of the converter, set the working state instruction of the chopper component according to the real-time voltage of the bus.

[0034] In some embodiments of the present application, the determining the operating state of the converter according to the comparison result includes:

[0035] If the effective value of the grid voltage is greater than the set value of the grid voltage, the converter enters the high ride-through state;

[0036] If the effective value of the grid voltage is less than or equal to the set value of the grid voltage, the converter exits the high ride-through state.

[0037] In some embodiments of the present application, the setting the working state instruction of the chopper component according to the real-time voltage of the bus based on the operating state of the converter includes:

[0038] When the converter enters the high ride-through state, compare the real-time voltage of the bus with the high ride-through overvoltage trigger value and the set value of the bus voltage;

[0039] When the real-time voltage of the bus reaches the high ride-through overvoltage trigger value, the chopper component is put into operation;

[0040] When the real-time voltage of the bus is less than or equal to the set value of the bus voltage, the chopper component exits operation;

[0041] Wherein, the high ride-through overvoltage trigger value is greater than the set value of the bus voltage.

[0042] In some embodiments of the present application, a preset grid real-time voltage matrix U0 and a preset grid voltage effective value E0 are set in the processing module. For the preset grid real-time voltage matrix U0, U0(U1, U2, U3, U4) is set, where U1 is the first preset grid real-time voltage, U2 is the second preset grid real-time voltage, U3 is the third preset grid real-time voltage, U4 is the fourth preset grid real-time voltage, and U1 < U2 < U3 < U4;

[0043] For the preset grid voltage effective value E0, E0(E1, E2, E3, E4) is set, where E1 is the first preset effective value, E2 is the second preset effective value, E3 is the third preset effective value, E4 is the fourth preset effective value, and E1 < E2 < E3 < E4;

[0044] Obtain the real-time grid voltage u, and set the effective value of the grid voltage according to the relationship between the real-time grid voltage u and each preset real-time grid voltage;

[0045] When u < U1, set the first preset effective value E1 as the effective value of the grid voltage;

[0046] When U1 ≤ u < U2, set the second preset effective value E2 as the effective value of the grid voltage;

[0047] When U2 ≤ u < U3, set the third preset effective value E3 as the effective value of the grid voltage;

[0048] When U3 ≤ u < U4, set the fourth preset effective value E4 as the effective value of the grid voltage.

[0049] The present invention provides a grid-side high-voltage protection system for a wind turbine converter, including: an acquisition module for acquiring historical voltage data on the grid side of the converter and the rated voltage of the converter; a determination module for determining the voltage ride-through level of the converter according to the historical voltage data and determining the specifications of the relevant components of the converter, where the relevant components of the converter include the chopper assembly; a detection module for detecting the real-time grid voltage and the real-time bus voltage on the grid side of the converter; a processing module for setting the working state instruction of the chopper assembly according to the real-time grid voltage and the real-time bus voltage; and a control module for controlling the chopper assembly according to the working state instruction set by the processing module to protect the converter.

[0050] Determine the specifications of the relevant components of the converter through the historical voltage data and the rated voltage of the converter, and judge whether the converter enters the high-ride state according to the real-time grid voltage. When entering the high-ride state, control the chopper assembly according to the real-time bus voltage, so that the wind power converter operates stably in the high-voltage operating range, avoid the grid-connected current from being too large and triggering the protection mechanism to trip, improve the stability of the power grid, and at the same time improve the working stability of each component in the wind turbine.

[0051] The technical solution of the present invention will be further described in detail below with reference to the drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 It is a schematic structural diagram of a grid-side high-voltage protection system for a wind turbine converter of the present invention; DETAILED DESCRIPTION OF THE EMBODIMENTS

[0053] The technical solution of the present invention will be further described below with reference to the drawings and embodiments.

[0054] It should be noted that the following detailed description is illustrative and aims to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the ordinary meanings commonly understood by those of ordinary skill in the technical field to which the present invention pertains.

[0055] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof, without excluding other elements or objects. The "first", "second", and similar terms used in the present invention do not denote any order, quantity, or importance, but are only used to distinguish different components. Terms such as "upper", "lower", "left", "right", "front", "rear", "vertical", "horizontal", "side", "bottom", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only relationship terms determined for the convenience of describing the structural relationship of each component or element of the present invention, and do not specifically refer to any component or element in the invention, and should not be construed as a limitation of the invention. Terms such as "fixedly connected", "connected", "connected" should be understood in a broad sense, which may mean a fixed connection, an integral connection, or a detachable connection; it may be directly connected or indirectly connected through an intermediate medium. For those relevant scientific research or technical personnel in the field, the specific meanings of the above terms in the present invention can be determined according to specific circumstances, and should not be construed as a limitation of the present invention.

[0056] Embodiment

[0057] When a high voltage appears in the power grid, the grid-side output power of the wind turbine converter is suppressed, causing the DC bus voltage of the converter to rise. When the bus voltage exceeds the limit voltage of the converter, it may cause damage to the converter, resulting in batch shutdown of the wind turbine generator sets and forming an impact on the power grid, thereby causing economic losses.

[0058] To solve the above problems, the present invention provides a grid-side high-voltage protection system for a wind turbine converter, as Figure 1 shown, including:

[0059] An acquisition module, which is used to acquire the historical voltage data of the grid side of the converter and the rated voltage of the converter.

[0060] A determination module, which is used to determine the voltage ride-through level of the converter according to the historical voltage data, and determine the specifications of the relevant components of the converter according to the voltage ride-through level. The relevant components of the converter include the chopper assembly.

[0061] A detection module, which is used to detect the real-time grid voltage and the real-time bus voltage on the grid side of the converter.

[0062] A processing module, which is used to set the working state instruction of the chopper component according to the real-time grid voltage and the real-time bus voltage.

[0063] A control module, which is used to control the chopper component according to the working state instruction set by the processing module to protect the converter.

[0064] In some embodiments of the present application, the historical voltage data includes the maximum grid voltage and the duration of maintaining the maximum grid voltage.

[0065] In an embodiment, high voltage ride-through refers to the ability of the unit to ensure continuous operation without tripping within a certain voltage increase range and time interval when the voltage increases due to grid faults or disturbances.

[0066] In some embodiments of the present application, the determining module determines the voltage ride-through level of the converter according to the historical voltage data, including:

[0067] Receiving the historical voltage data on the grid side of the converter and the rated voltage of the converter acquired by the acquiring module.

[0068] Determining the voltage ratio between the maximum grid voltage and the rated voltage, and determining the voltage ride-through level of the converter according to the voltage ratio.

[0069] Correcting the voltage ride-through level of the converter according to the duration of maintaining the maximum grid voltage to obtain the final voltage ride-through level of the converter.

[0070] In this embodiment, the high voltage ride-through ability of the converter grid can be determined according to the ratio of the grid voltage to the rated voltage and the ability to ensure continuous operation without tripping.

[0071] In some embodiments of the present application, the components related to the converter further include a circuit breaker, a filter capacitor, a filter reactor, a grid connection switch, and an auxiliary transformer.

[0072] In this embodiment, during the fault ride-through process, the components with greater influence are the components related to the grid side and the chopper component. Therefore, when high voltage ride-through occurs, the insulation voltage or rated voltage of the components related to the converter should be greater than the grid side voltage.

[0073] In some embodiments of the present application, a preset voltage ratio matrix V0 and a preset voltage ride-through level matrix L0 are set in the determination module. For the preset voltage ratio matrix V0, V0(V1, V2, V3, V4) is set, where V1 is the first preset voltage ratio, V2 is the second preset voltage ratio, V3 is the third preset voltage ratio, V4 is the fourth preset voltage ratio, and V1 < V2 < V3 < V4.

[0074] For the preset voltage ride-through level matrix L0, L0(L1, L2, L3, L4) is set, where L1 is the first preset voltage ride-through level; L2 is the second preset voltage ride-through level; L3 is the third preset voltage ride-through level; L4 is the fourth preset voltage ride-through level, and L1 < L2 < L3 < L4.

[0075] The determination module is configured to obtain the maximum grid voltage on the grid side of the converter and the rated voltage of the converter, calculate the voltage ratio v of the maximum grid voltage to the rated voltage, and set the voltage ride-through level of the converter according to the relationship between the voltage ratio v and each preset voltage ratio.

[0076] When v < V1, the first preset voltage ride-through level L1 is set as the voltage ride-through level of the converter.

[0077] When V1 ≤ v < V2, the second preset voltage ride-through level L2 is set as the voltage ride-through level of the converter.

[0078] When V2 ≤ v < V3, the third preset voltage ride-through level L3 is set as the voltage ride-through level of the converter.

[0079] When V3 ≤ v < V4, the fourth preset voltage ride-through level L4 is set as the voltage ride-through level of the converter.

[0080] In some embodiments of the present application, a preset duration matrix T0 is set in the determination module. For the preset duration matrix T0, T0(T1, T2, T3, T4) is set, where T1 is the first preset duration, T2 is the second preset duration, T3 is the third preset duration, T4 is the first preset duration, and T1 < T2 < T3 < T4.

[0081] After determining the i-th preset voltage ride-through level Li as the voltage ride-through level of the converter according to the voltage ratio v, where i = 1, 2, 3, 4 at this time; obtain the duration t of maintaining the maximum grid voltage, and correct the i-th preset voltage ride-through level Li according to the relationship between the duration t of maintaining the maximum grid voltage and each preset duration to obtain the final voltage ride-through level of the converter.

[0082] When t < T1, the i-th preset voltage ride-through level Li is used as the final voltage ride-through level of the converter.

[0083] When T1 ≤ t < T2, the i-th preset voltage ride-through level Li is increased by one level and used as the final voltage ride-through level of the converter. If it is the fourth preset voltage ride-through level L4 at this time, the fourth preset voltage ride-through level L4 is directly used as the final voltage ride-through level of the converter.

[0084] When T2 ≤ t < T3, the i-th preset voltage ride-through level Li is increased by two levels and used as the final voltage ride-through level of the converter. If it is the fourth preset voltage ride-through level L4 at this time, the fourth preset voltage ride-through level L4 is directly used as the final voltage ride-through level of the converter.

[0085] When T3 ≤ t < T4, the i-th preset voltage ride-through level Li is increased by three levels and used as the final voltage ride-through level of the converter. If it is the fourth preset voltage ride-through level L4 at this time, the fourth preset voltage ride-through level L4 is directly used as the final voltage ride-through level of the converter.

[0086] In some embodiments of the present application, the processing module sets the working state instruction of the chopper component according to the real-time grid voltage and the real-time bus voltage, including:

[0087] Determine the effective value of the grid voltage according to the real-time grid voltage.

[0088] Compare the effective value of the grid voltage with the set value of the grid voltage, and determine the operating state of the converter according to the comparison result.

[0089] Based on the operating state of the converter, set the working state instruction of the chopper component according to the real-time bus voltage.

[0090] In some embodiments of the present application, the determining the operating state of the converter according to the comparison result includes:

[0091] If the effective value of the grid voltage is greater than the set value of the grid voltage, the converter enters the high-ride-through state.

[0092] If the effective value of the grid voltage is less than or equal to the set value of the grid voltage, the converter exits the high-ride-through state.

[0093] In this embodiment, by comparing the effective value of the grid voltage with the set value of the grid voltage, it is determined whether the converter enters the high-ride-through state, so as to subsequently set the working state instruction of the chopper component according to the real-time bus voltage.

[0094] In some embodiments of the present application, setting the working state instruction of the chopper component according to the real-time bus voltage based on the operating state of the converter includes:

[0095] When the converter enters the high-ride-through state, compare the real-time bus voltage with the high-ride-through overvoltage trigger value and the bus voltage set value.

[0096] When the real-time bus voltage reaches the high-ride-through overvoltage trigger value, the chopper component is put into operation.

[0097] When the real-time bus voltage is less than or equal to the bus voltage set value, the chopper component exits the operating state.

[0098] Wherein, the high-ride-through overvoltage trigger value is greater than the bus voltage set value.

[0099] In this embodiment, to ensure that the converter operates continuously and the unit does not trip off the grid during high-voltage faults, when it is detected that the effective value of the converter grid voltage reaches the grid voltage set value, it is determined to enter the high-ride-through state, and the high-ride-through state flag of the converter is set. At the same time, by setting a reasonable high-ride-through overvoltage trigger value for the Chopper component, the Chopper component is used to release the excess energy in the power system during high-ride-through, thereby stabilizing the DC bus voltage value. When the bus voltage rises to the high-ride-through overvoltage trigger value, the Chopper component is put into operation to discharge the excess energy. When the bus voltage is less than the bus voltage set value, the Chopper component exits the operating state. When the effective value of the grid voltage is lower than the grid voltage set value, the unit exits the high-ride-through state. During the operation of the Chopper component, the internal logic of the software has real-time protection functions, such as Chopper overload, etc. In addition, hardware overcurrent protection points and voltage overvoltage protection points are also set during the entire fault ride-through process.

[0100] In some embodiments of the present application, a preset grid real-time voltage matrix U0 and a preset grid voltage effective value E0 are set in the processing module. For the preset grid real-time voltage matrix U0, set U0(U1, U2, U3, U4), where U1 is the first preset grid real-time voltage, U2 is the second preset grid real-time voltage, U3 is the third preset grid real-time voltage, U4 is the fourth preset grid real-time voltage, and U1 < U2 < U3 < U4.

[0101] For the preset grid voltage effective value E0, set E0(E1, E2, E3, E4), where E1 is the first preset effective value, E2 is the second preset effective value, E3 is the third preset effective value, E4 is the fourth preset effective value, and E1 < E2 < E3 < E4.

[0102] Obtain the real-time grid voltage u, and set the effective value of the grid voltage according to the relationship between the real-time grid voltage u and each preset real-time grid voltage.

[0103] When u < U1, set the first preset effective value E1 as the effective value of the grid voltage.

[0104] When U1 ≤ u < U2, set the second preset effective value E2 as the effective value of the grid voltage.

[0105] When U2 ≤ u < U3, set the third preset effective value E3 as the effective value of the grid voltage.

[0106] When U3 ≤ u < U4, set the fourth preset effective value E4 as the effective value of the grid voltage.

[0107] In this embodiment, when the detection module performs detection, a high-precision sampling resistor is used, which can greatly improve the sampling accuracy. At the same time, the sampling delay is reduced from the millisecond level to the microsecond level, which not only improves the accuracy of the detection data, provides a basis for the control of the subsequent high-voltage protection system, realizes stable operation during the high-voltage ride-through of the converter, and reduces the converter failure rate.

[0108] The present invention provides a grid-side high-voltage protection system for a wind turbine converter, which determines the specifications of the relevant components of the converter through historical voltage data and the rated voltage of the converter, and judges whether the converter enters the high-voltage ride-through state according to the real-time grid voltage. When entering the high-voltage ride-through state, the chopper component is controlled according to the real-time bus voltage, so that the wind power converter operates stably in the high-voltage operating range, avoids the grid-connected current from being too large and triggering the protection mechanism to trip, improves the stability of the power grid, and at the same time improves the operating stability of each component in the wind turbine.

[0109] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that they can still modify or equivalently replace the technical solutions of the present invention, and these modifications or equivalent replacements cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present invention.

[0110] The system provided by the above embodiments is only illustrated by the division of the above functional modules. In practical applications, the above functions can be assigned to different functional modules according to needs, that is, the modules or steps in the embodiments of the present invention can be further decomposed or combined. For example, the modules in the above embodiments can be merged into one module, or further split into multiple sub-modules to complete all or part of the functions described above. The names of the modules and steps involved in the embodiments of the present invention are only used to distinguish each module or step, and are not regarded as an improper limitation of the present invention.

[0111] Those skilled in the art should be able to realize that the modules and method steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, computer software, or a combination of the two. The programs corresponding to the software modules and method steps can be placed in a random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium well-known in the technical field. To clearly illustrate the interchangeability of electronic hardware and software, the composition and steps of each example have been generally described according to functions in the above description. Whether these functions are executed in the form of electronic hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present invention.

Claims

1. A grid-side high-voltage protection system for a wind turbine converter, characterized in that, Including: An acquisition module, which is used to acquire the historical voltage data of the grid side of the converter and the rated voltage of the converter; A determination module, which is used to determine the voltage ride-through level of the converter according to the historical voltage data, and determine the specifications of the relevant components of the converter according to the voltage ride-through level. The relevant components of the converter include the chopper assembly; A detection module, which is used to detect the real-time grid voltage and the real-time bus voltage of the grid side of the converter; A processing module, which is used to set the working state instruction of the chopper assembly according to the real-time grid voltage and the real-time bus voltage; A control module, which is used to control the chopper assembly according to the working state instruction set by the processing module to protect the converter; The determination module determines the voltage ride-through level of the converter according to the historical voltage data, including: Receiving the historical voltage data of the grid side of the converter and the rated voltage of the converter acquired by the acquisition module; Determining the voltage ratio between the maximum grid voltage and the rated voltage, and determining the voltage ride-through level of the converter according to the voltage ratio; Correcting the voltage ride-through level of the converter according to the duration of maintaining the maximum grid voltage to obtain the final voltage ride-through level of the converter; A preset voltage ratio matrix V0 and a preset voltage ride-through level matrix L0 are set in the determination module. For the preset voltage ratio matrix V0, V0 is set as (V1, V2, V3, V4), where V1 is the first preset voltage ratio, V2 is the second preset voltage ratio, V3 is the third preset voltage ratio, V4 is the fourth preset voltage ratio, and V1 < V2 < V3 < V4; For the preset voltage ride-through level matrix L0, L0 is set as (L1, L2, L3, L4), where L1 is the first preset voltage ride-through level; L2 is the second preset voltage ride-through level; L3 is the third preset voltage ride-through level; L4 is the fourth preset voltage ride-through level, and L1 < L2 < L3 < L4; The determination module is used to acquire the maximum grid voltage of the grid side of the converter and the rated voltage of the converter, calculate the voltage ratio v between the maximum grid voltage and the rated voltage, and set the voltage ride-through level of the converter according to the relationship between the voltage ratio v and each preset voltage ratio; When v < V1, set the first preset voltage ride-through level L1 as the voltage ride-through level of the converter; When V1 ≤ v < V2, set the second preset voltage ride-through level L2 as the voltage ride-through level of the converter; When V2 ≤ v < V3, set the third preset voltage ride-through level L3 as the voltage ride-through level of the converter; When V3 ≤ v < V4, set the fourth preset voltage ride-through level L4 as the voltage ride-through level of the converter; A preset duration matrix T0 is set in the determination module. For the preset duration matrix T0, T0(T1, T2, T3, T4) is set, where T1 is the first preset duration, T2 is the second preset duration, T3 is the third preset duration, T4 is the first preset duration, and T1 < T2 < T3 < T4; After determining the i-th preset voltage crossing level Li as the voltage crossing level of the converter according to the voltage ratio v, where i = 1, 2, 3, 4 at this time; obtain the duration t of maintaining the maximum grid voltage, and correct the i-th preset voltage crossing level Li according to the relationship between the duration t of maintaining the maximum grid voltage and each preset duration to obtain the final voltage crossing level of the converter; When t < T1, the i-th preset voltage crossing level Li is used as the final voltage crossing level of the converter; When T1 ≤ t < T2, the i-th preset voltage crossing level Li is increased by one level and then used as the final voltage crossing level of the converter. If it is the fourth preset voltage crossing level L4 at this time, the fourth preset voltage crossing level L4 is directly used as the final voltage crossing level of the converter; When T2 ≤ t < T3, the i-th preset voltage crossing level Li is increased by two levels and then used as the final voltage crossing level of the converter. If it is the fourth preset voltage crossing level L4 at this time, the fourth preset voltage crossing level L4 is directly used as the final voltage crossing level of the converter; When T3 ≤ t < T4, the i-th preset voltage crossing level Li is increased by three levels and then used as the final voltage crossing level of the converter. If it is the fourth preset voltage crossing level L4 at this time, the fourth preset voltage crossing level L4 is directly used as the final voltage crossing level of the converter; The processing module sets the working state instruction of the chopper component according to the real-time grid voltage and the real-time bus voltage, including: Determine the effective value of the grid voltage according to the real-time grid voltage; Compare the effective value of the grid voltage with the set value of the grid voltage, and determine the operating state of the converter according to the comparison result; Based on the operating state of the converter, set the working state instruction of the chopper component according to the real-time bus voltage; A preset real-time grid voltage matrix U0 and a preset effective value E0 of the grid voltage are set in the processing module. For the preset real-time grid voltage matrix U0, U0 is set as (U1, U2, U3, U4), where U1 is the first preset real-time grid voltage, U2 is the second preset real-time grid voltage, U3 is the third preset real-time grid voltage, U4 is the fourth preset real-time grid voltage, and U1 < U2 < U3 < U4; For the preset effective value E0 of the grid voltage, E0 is set as (E1, E2, E3, E4), where E1 is the first preset effective value, E2 is the second preset effective value, E3 is the third preset effective value, E4 is the fourth preset effective value, and E1 < E2 < E3 < E4; Obtain the real-time grid voltage u, and set the effective value of the grid voltage according to the relationship between the real-time grid voltage u and each preset real-time grid voltage; When u < U1, set the first preset effective value E1 as the effective value of the grid voltage; When U1 ≤ u < U2, set the second preset effective value E2 as the effective value of the grid voltage; When U2 ≤ u < U3, set the third preset effective value E3 as the effective value of the grid voltage; When U3 ≤ u < U4, set the fourth preset effective value E4 as the effective value of the grid voltage.

2. The grid-side high-voltage protection system for a wind turbine converter according to claim 1, wherein The historical voltage data includes the maximum grid voltage and the duration of maintaining the maximum grid voltage.

3. A grid-side high-voltage protection system for a wind turbine converter according to claim 1, characterized in that The components related to the converter further include a circuit breaker, a filter capacitor, a filter reactor, a grid-connected switch, and an auxiliary transformer.

4. A grid-side high-voltage protection system for a wind turbine converter according to claim 1, characterized in that Determining the operating state of the converter according to the comparison result includes: If the effective value of the grid voltage is greater than the set value of the grid voltage, the converter enters the high-ride-through state; If the effective value of the grid voltage is less than or equal to the set value of the grid voltage, the converter exits the high-ride-through state.

5. A grid-side high-voltage protection system for a wind turbine converter according to claim 4, characterized in that Based on the operating state of the converter, setting the working state command of the chopper component according to the real-time bus voltage includes: When the converter enters the high-ride-through state, compare the real-time bus voltage with the high-ride-through overvoltage trigger value and the set value of the bus voltage; When the real-time bus voltage reaches the high-ride-through overvoltage trigger value, the chopper component is put into operation; When the real-time bus voltage is less than or equal to the set value of the bus voltage, the chopper component exits operation; wherein, the high-ride-through overvoltage trigger value is greater than the set value of the bus voltage.

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