High voltage ride through bus voltage control method and system for full power converter

Abstract

The invention provides a high voltage ride through bus voltage control method and system for a full power converter, and the method comprises the steps: connecting a DC unloading Chopper device at a DC side of the full power converter, and obtaining the DC bus voltage of a power grid in real time; when the direct current bus voltage has a sudden rise fault, obtaining a direct current bus voltage actual measurement value of a power grid, and determining an unloading input threshold value and an unloading cut-out threshold value of a grid-side Chopper control strategy according to the direct current bus voltage actual measurement value; and determining the duty ratio of the DC unloading Chopper device according to the measured value of the DC bus voltage and the unloading input threshold value and the unloading cut-out threshold value of the grid-side Chopper control strategy, and controlling the DC unloading Chopper device based on the duty ratio to realize the high voltage ride through of the full-power converter. According to the technical scheme provided by the invention, the unloading input time can be accurately controlled, so that the unloading device can dynamically absorb surplus energy according to the voltage amplitude of the direct-current bus, and the capacity of smoothly adjusting the unloading power is achieved.

Description

Technical Field

[0001] The present application relates to the field of high voltage ride through technology, and in particular to a high voltage ride through bus voltage control method and system for a full power converter. Background Art

[0002] For full-power converters based on permanent magnet synchronous generators, since the machine-side converter is isolated from the grid by the busbar, the fault response plan for the grid-side converter is the focus. When the converter uses conventional control strategies, a sudden grid surge fault occurs. Due to the limitation of the response speed of the current controller, a current shock will occur during the transient state of voltage increase and recovery, which may cause the busbar to shut down due to overvoltage in severe cases. During the steady state of voltage increase, if no response strategy is adopted, overmodulation will occur, resulting in out-of-control of the grid-side output current and busbar overvoltage fault. In severe cases, a large amount of harmonic current will also cause overcurrent shutdown. Therefore, it is urgent to propose a solution that can accurately and quickly control the input and output of load shedding to ensure the safe and stable operation of the power grid. Summary of the invention

[0003] The present application provides a high voltage ride through bus voltage control method and system for a full power converter, so as to at least solve the technical problems of low accuracy and slow speed of high voltage ride through.

[0004] The first aspect of the present application provides a high voltage ride through bus voltage control method for a full power converter, the method comprising:

[0005] A DC unloading Chopper device is connected to the DC side of the full-power converter to obtain the DC bus voltage of the power grid in real time;

[0006] When a sudden rise fault occurs in the DC bus voltage, an actual measured value of the DC bus voltage of the power grid is obtained, and a load shedding input threshold and a load shedding cut-out threshold of a grid-side Chopper control strategy are determined according to the actual measured value of the DC bus voltage;

[0007] The duty cycle of the DC load shedding Chopper device is determined according to the measured value of the DC bus voltage, the load shedding input threshold and the load shedding cut-out threshold of the grid-side Chopper control strategy, and the DC load shedding Chopper device is controlled based on the duty cycle to achieve high voltage ride-through of the full-power converter.

[0008] Preferably, the DC unloading Chopper device comprises: a Chopper resistor and a power electronic switch;

[0009] The Chopper resistor is connected to the power electronic switch.

[0010] Further, the step of determining a load shedding input threshold and a load shedding cut-out threshold of a grid-side Chopper control strategy according to the measured value of the DC bus voltage includes:

[0011] Obtaining three-phase voltage values ​​of the DC bus voltage actual measurement value, and screening out the maximum voltage value from the three-phase voltage values;

[0012] The load shedding input threshold and the load shedding cut-out threshold are determined according to the maximum voltage.

[0013] Furthermore, the calculation formula of the load shedding input threshold is as follows:

[0014]

[0015] In the formula, is the load shedding threshold, U cutin is the preset initial threshold for load shedding, k is the bus voltage adjustment coefficient, U max is the maximum voltage, U b Adjust the reference value for the bus voltage;

[0016] The calculation formula of the unloading cut-out threshold is as follows:

[0017]

[0018] In the formula, is the load unloading cut-out threshold, U cutout is the preset load shedding initial threshold, k is the bus voltage adjustment coefficient, U max is the maximum voltage, U b Adjust the reference value for the bus voltage.

[0019] Further, the step of determining the duty cycle of the DC load shedding Chopper device according to the measured value of the DC bus voltage, the load shedding input threshold and the load shedding cut-out threshold of the grid-side Chopper control strategy includes:

[0020] When the measured value of the DC bus voltage is greater than the load shedding input threshold, the duty cycle of the DC load shedding Chopper device is 1;

[0021] When the measured value of the DC bus voltage is less than the load unloading cut-out threshold, the duty cycle of the DC unloading Chopper device is 0;

[0022] When the measured value of the DC bus voltage is less than or equal to the load shedding input threshold and greater than or equal to the load shedding cut-out threshold, the duty cycle of the DC load shedding Chopper device is D.

[0023] Furthermore, the calculation formula of the duty cycle D is as follows:

[0024]

[0025] Where U dc is the measured value of DC bus voltage, is the DC bus voltage reference value, ΔU dcMax It is the DC bus voltage deviation value when the load is fully unloaded.

[0026] Furthermore, the DC unloading Chopper device is controlled based on the duty cycle to achieve high voltage ride through of the full power converter, including:

[0027] When the measured value of the DC bus voltage is greater than the load shedding input threshold, controlling the power electronic switch in the DC load shedding Chopper device to close with a duty cycle of 1;

[0028] When the measured value of the DC bus voltage is less than the load unloading cut-out threshold, the power electronic switch in the DC unloading Chopper device is controlled to be turned off with a duty cycle of;

[0029] When the measured value of the DC bus voltage is less than or equal to the load shedding input threshold and greater than or equal to the load shedding cut-out threshold, the duty cycle of the DC load shedding Chopper device is controlled to be D.

[0030] The second aspect of the present application provides a high voltage ride through bus voltage control system for a full power converter, comprising:

[0031] An acquisition module is used to connect a DC load unloading Chopper device to the DC side of the full-power converter and acquire the DC bus voltage of the power grid in real time;

[0032] A determination module, used for obtaining a measured value of the DC bus voltage of the power grid when a sudden rise fault occurs in the DC bus voltage, and determining a load shedding input threshold and a load shedding cut-out threshold of a grid-side Chopper control strategy according to the measured value of the DC bus voltage;

[0033] A control module is used to determine the duty cycle of the DC load shedding Chopper device according to the actual measured value of the DC bus voltage, the load shedding input threshold and the load shedding cut-out threshold of the grid-side Chopper control strategy, and control the DC load shedding Chopper device based on the duty cycle to achieve high voltage ride-through of the full-power converter.

[0034] The third aspect of the present application provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method described in the first aspect is implemented.

[0035] A fourth aspect of the present application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method described in the first aspect of the present application.

[0036] The technical solution provided by the embodiments of the present application brings at least the following beneficial effects:

[0037] The present application proposes a bus voltage control method and system for high voltage crossing of a full power converter, the method comprising: connecting a DC unloading Chopper device to the DC side of the full power converter, and obtaining the DC bus voltage of the power grid in real time; obtaining the measured value of the DC bus voltage of the power grid when a sudden rise fault occurs in the DC bus voltage, and determining the unloading input threshold and unloading cut-out threshold of the grid-side Chopper control strategy according to the measured value of the DC bus voltage; determining the duty cycle of the DC unloading Chopper device according to the measured value of the DC bus voltage, the unloading input threshold and the unloading cut-out threshold of the grid-side Chopper control strategy, and controlling the DC unloading Chopper device based on the duty cycle to achieve high voltage crossing of the full power converter. The technical solution proposed in the present application can accurately control the unloading input time, so that the unloading device can dynamically absorb surplus energy according to the DC bus voltage amplitude, and has the ability to smoothly adjust the unloading power.

[0038] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0040] Figure 1 A flowchart of a high voltage ride through bus voltage control method for a full power converter provided according to an embodiment of the present application;

[0041] Figure 2 A schematic diagram of a DC load shedding Chopper device provided according to an embodiment of the present application connected to a full power converter;

[0042] Figure 3 The present invention is a structural diagram of a high voltage ride-through bus voltage control system for a full power converter according to an embodiment of the present application. DETAILED DESCRIPTION

[0043] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0044] The present application proposes a high voltage ride-through bus voltage control method and system for a full-power converter, the method comprising: connecting a DC unloading Chopper device to the DC side of the full-power converter, and obtaining the DC bus voltage of the power grid in real time; obtaining the measured value of the DC bus voltage of the power grid when a sudden rise fault occurs in the DC bus voltage, and determining the unloading input threshold and unloading cut-out threshold of the grid-side Chopper control strategy according to the measured value of the DC bus voltage; determining the duty cycle of the DC unloading Chopper device according to the measured value of the DC bus voltage, the unloading input threshold and the unloading cut-out threshold of the grid-side Chopper control strategy, and controlling the DC unloading Chopper device based on the duty cycle to achieve high voltage ride-through of the full-power converter. The technical solution proposed in the present application can accurately control the unloading input time, so that the unloading device can dynamically absorb surplus energy according to the DC bus voltage amplitude, and has the ability to smoothly adjust the unloading power.

[0045] The following describes a high voltage ride-through bus voltage control method and system for a full-power converter according to an embodiment of the present application with reference to the accompanying drawings.

[0046] Embodiment 1

[0047] Figure 1 Flow chart of a high voltage ride through bus voltage control method for a full power converter according to one embodiment of the present application, as shown in FIG. Figure 1 As shown, the method includes:

[0048] Step 1: Connect a DC unloading Chopper device to the DC side of the full power converter, and obtain the DC bus voltage of the power grid in real time;

[0049] It should be noted that if Figure 2 As shown, the DC unloading Chopper device includes: a Chopper resistor and a power electronic switch S1; the Chopper resistor is connected to the power electronic switch S1.

[0050] In the transient process of voltage rise and recovery, there is a current shock, which may cause bus overvoltage. When the control strategy cannot quickly suppress the DC bus overvoltage, a DC unloading circuit, namely a DC unloading Chopper device, is used to suppress it. The DC unloading circuit connects the Chopper resistor directly to the power electronic switch S1 and then connects it to the DC side, and controls the switching of the Chopper resistor through the power switch. When the unit is operating normally, the DC Chopper circuit will not be put into operation. When the voltage at the grid connection point rises, the power switch will be turned on to avoid overvoltage and overcurrent caused by power imbalance, and the unloading branch will be put into operation to consume unbalanced power. The control of the DC unloading circuit is independent of the converter control, and its switching needs to be controlled separately.

[0051] Step 2: When a sudden rise fault occurs in the DC bus voltage, an actual measured value of the DC bus voltage of the power grid is obtained, and a load shedding input threshold and a load shedding cut-out threshold of a grid-side Chopper control strategy are determined according to the actual measured value of the DC bus voltage;

[0052] For example, when the DC bus voltage changes from 1065V to 1350V within 1-2ms, it is determined that a sudden rise fault occurs.

[0053] In the disclosed embodiment, the step of determining the load shedding input threshold and the load shedding cut-out threshold of the grid-side Chopper control strategy according to the measured value of the DC bus voltage includes:

[0054] Obtaining three-phase voltage values ​​of the DC bus voltage actual measurement value, and screening out the maximum voltage value from the three-phase voltage values;

[0055] The load shedding input threshold and the load shedding cut-out threshold are determined according to the maximum voltage.

[0056] The calculation formula of the load shedding input threshold is as follows:

[0057]

[0058] In the formula, is the load shedding input threshold, U cutin is the preset initial threshold for load shedding, k is the bus voltage adjustment coefficient, where k is equal to 1, U max is the maximum voltage, U b Adjust the reference value for the bus voltage;

[0059] The calculation formula of the unloading cut-out threshold is as follows:

[0060]

[0061] In the formula, is the load unloading cut-out threshold, U cutoutis the preset load shedding initial threshold, k is the bus voltage adjustment coefficient, U max is the maximum voltage, U b Adjusts the reference value for the bus voltage.

[0062] Step 3: Determine the duty cycle of the DC load shedding Chopper device according to the measured value of the DC bus voltage, the load shedding input threshold and the load shedding cut-out threshold of the grid-side Chopper control strategy, and control the DC load shedding Chopper device based on the duty cycle to achieve high voltage ride-through of the full-power converter.

[0063] In the disclosed embodiment, the step of determining the duty cycle of the DC load shedding Chopper device according to the measured value of the DC bus voltage, the load shedding input threshold and the load shedding cut-out threshold of the grid-side Chopper control strategy includes:

[0064] When the measured value of the DC bus voltage is greater than the load shedding input threshold, the duty cycle of the DC load shedding Chopper device is 1;

[0065] When the measured value of the DC bus voltage is less than the load unloading cut-out threshold, the duty cycle of the DC unloading Chopper device is 0;

[0066] When the measured value of the DC bus voltage is less than or equal to the load shedding input threshold and greater than or equal to the load shedding cut-out threshold, the duty cycle of the DC load shedding Chopper device is D.

[0067] The calculation formula of the duty cycle D is as follows:

[0068]

[0069] Where U dc is the measured value of DC bus voltage, is the DC bus voltage reference value, ΔU dcMax It is the DC bus voltage deviation value when the load is fully unloaded.

[0070] Among them, the DC bus voltage deviation value ΔU when the load is fully unloaded dcMax The rated voltage of the DC bus film capacitor is usually 1100V. Considering that the 1.15 times overvoltage value of the DC bus capacitor is 1265V, it can withstand up to 30 minutes a day without affecting its service life. In the formula, the voltage deviation value of the DC bus when fully unloaded is set to 1265V.

[0071] Furthermore, the DC unloading Chopper device is controlled based on the duty cycle to achieve high voltage ride through of the full power converter, including:

[0072] When the measured value of the DC bus voltage is greater than the load shedding input threshold, controlling the power electronic switch in the DC load shedding Chopper device to close with a duty cycle of 1;

[0073] When the measured value of the DC bus voltage is less than the load unloading cut-out threshold, the power electronic switch in the DC unloading Chopper device is controlled to be turned off with a duty cycle of;

[0074] When the measured value of the DC bus voltage is less than or equal to the load shedding input threshold and greater than or equal to the load shedding cut-out threshold, the duty cycle of the DC load shedding Chopper device is controlled to be D.

[0075] It should be noted that when the DC bus voltage is greater than the input threshold, the load is put into unloading, and when the DC bus voltage is less than the cut-out threshold, the load is cut out. A hysteresis loop is set between the two thresholds. A lower threshold setting has a fast response speed, but in the process of increasing the grid voltage, the uncontrolled rectifier current will flow from the grid to the bus and then be consumed by the unloading resistor, resulting in loss of power generation. A higher threshold setting can avoid the input of unloading during the increase of the grid voltage, but sacrifices the response speed. Combined with the DC bus voltage reference value, the unloading action is driven by pulse width modulation. The duty cycle value is linearly related to the deviation between the actual value and the reference value of the DC bus voltage. Since the DC bus voltage reference value is dynamically adjusted as the grid voltage increases, the unloading input and cut-out thresholds must also be dynamically adjusted as the grid voltage increases to avoid frequent switching. Furthermore, in the transient state of the grid voltage increase, since the DC bus voltage reference value threshold is relatively low, the load can be quickly put into unloading to suppress overvoltage. During the steady state of the grid voltage increase, the unloading input can avoid unnecessary active power consumption.

[0076] In summary, the high voltage ride-through bus voltage control method for full-power converters proposed in this embodiment can accurately control the unloading time, so that the unloading device can dynamically absorb surplus energy according to the DC bus voltage amplitude, and has the ability to smoothly adjust the unloading power; at the same time, the HVRT mode is automatically turned on according to the voltage fluctuation of the grid connection point to ensure that the full-power wind turbine can successfully ride through the high voltage fault. It effectively avoids the DC bus voltage fluctuation caused by the frequent switching of the Chopper circuit and the grid-side voltage and current waveform distortion, and also greatly reduces the economic cost.

[0077] Embodiment 2

[0078] Figure 3 FIG. 1 is a structural diagram of a high voltage ride through bus voltage control system for a full power converter according to an embodiment of the present application, such as Figure 3 As shown, the system comprises:

[0079] An acquisition module 100 is used to connect a DC unloading Chopper device to the DC side of the full-power converter and acquire the DC bus voltage of the power grid in real time;

[0080] Wherein, the DC unloading Chopper device comprises: a Chopper resistor and a power electronic switch;

[0081] The Chopper resistor is connected to the power electronic switch.

[0082] A determination module 200 is used to obtain a measured value of the DC bus voltage of the power grid when a sudden rise fault occurs in the DC bus voltage, and determine a load shedding input threshold and a load shedding cut-out threshold of a grid-side Chopper control strategy according to the measured value of the DC bus voltage;

[0083] The control module 300 is used to determine the duty cycle of the DC load shedding Chopper device according to the actual measured value of the DC bus voltage, the load shedding input threshold and the load shedding cut-out threshold of the grid-side Chopper control strategy, and control the DC load shedding Chopper device based on the duty cycle to achieve high voltage ride-through of the full-power converter.

[0084] In the embodiment of the present disclosure, the determining module 200 is further used to:

[0085] Obtaining three-phase voltage values ​​of the DC bus voltage actual measurement value, and screening out the maximum voltage value from the three-phase voltage values;

[0086] The load shedding input threshold and the load shedding cut-out threshold are determined according to the maximum voltage.

[0087] The calculation formula of the load shedding input threshold is as follows:

[0088]

[0089] In the formula, is the load shedding input threshold, U cutin is the preset initial threshold for load shedding, k is the bus voltage adjustment coefficient, U max is the maximum voltage, U b Adjust the reference value for the bus voltage;

[0090] The calculation formula of the unloading cut-out threshold is as follows:

[0091]

[0092] In the formula, is the load unloading cut-out threshold, U cutout is the preset load shedding initial threshold, k is the bus voltage adjustment coefficient, U max is the maximum voltage, Ub Adjust the reference value for the bus voltage.

[0093] In the embodiment of the present disclosure, the control module 300 is also used for:

[0094] When the measured value of the DC bus voltage is greater than the load shedding input threshold, the duty cycle of the DC load shedding Chopper device is 1;

[0095] When the measured value of the DC bus voltage is less than the load unloading cut-out threshold, the duty cycle of the DC unloading Chopper device is 0;

[0096] When the measured value of the DC bus voltage is less than or equal to the load shedding input threshold and greater than or equal to the load shedding cut-out threshold, the duty cycle of the DC load shedding Chopper device is D.

[0097] The calculation formula of the duty cycle D is as follows:

[0098]

[0099] Where U dc is the measured value of DC bus voltage, is the DC bus voltage reference value, ΔU dcMax It is the DC bus voltage deviation value when the load is fully unloaded.

[0100] In the embodiment of the present disclosure, the control module 300 is also used for:

[0101] When the measured value of the DC bus voltage is greater than the load shedding input threshold, controlling the power electronic switch in the DC load shedding Chopper device to close with a duty cycle of 1;

[0102] When the measured value of the DC bus voltage is less than the load unloading cut-out threshold, the power electronic switch in the DC unloading Chopper device is controlled to be turned off with a duty cycle of;

[0103] When the measured value of the DC bus voltage is less than or equal to the load shedding input threshold and greater than or equal to the load shedding cut-out threshold, the duty cycle of the DC load shedding Chopper device is controlled to be D.

[0104] In summary, the high voltage ride-through bus voltage control system for a full-power converter proposed in this embodiment can accurately control the unloading input time, so that the unloading device can dynamically absorb surplus energy according to the DC bus voltage amplitude, and has the ability to smoothly adjust the unloading power.

[0105] Embodiment 3

[0106] In order to implement the above embodiments, the present disclosure further proposes an electronic device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method described in Embodiment 1 is implemented.

[0107] Embodiment 4

[0108] In order to implement the above embodiments, the present disclosure further proposes a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the method described in the first embodiment is implemented.

[0109] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0110] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0111] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A high voltage ride through bus voltage control method for a full power converter, characterized in that: The method comprises: A DC unloading Chopper device is connected to the DC side of the full-power converter to obtain the DC bus voltage of the power grid in real time; When a sudden rise fault occurs in the DC bus voltage, an actual measured value of the DC bus voltage of the power grid is obtained, and a load shedding input threshold and a load shedding cut-out threshold of a grid-side Chopper control strategy are determined according to the actual measured value of the DC bus voltage; The duty cycle of the DC load shedding Chopper device is determined according to the measured value of the DC bus voltage, the load shedding input threshold and the load shedding cut-out threshold of the grid-side Chopper control strategy, and the DC load shedding Chopper device is controlled based on the duty cycle to achieve high voltage ride-through of the full-power converter.

2. The method according to claim 1, characterized in that The DC load unloading Chopper device comprises: a Chopper resistor and a power electronic switch; The Chopper resistor is connected to the power electronic switch.

3. The method according to claim 2, characterized in that The step of determining the load shedding input threshold and load shedding cut-out threshold of the grid-side Chopper control strategy according to the measured value of the DC bus voltage includes: Obtaining three-phase voltage values ​​of the DC bus voltage actual measurement value, and screening out the maximum voltage value from the three-phase voltage values; The load shedding input threshold and the load shedding cut-out threshold are determined according to the maximum voltage.

4. The method according to claim 3, characterized in that The calculation formula of the load shedding input threshold is as follows: In the formula, is the load shedding input threshold, U cutin is the preset initial threshold for load shedding, k is the bus voltage adjustment coefficient, U max is the maximum voltage, U b Adjust the reference value for the bus voltage; The calculation formula of the unloading cut-out threshold is as follows: In the formula, is the load unloading cut-out threshold, U cutout is the preset load shedding initial threshold, k is the bus voltage adjustment coefficient, U max is the maximum voltage, U b Adjust the reference value for the bus voltage.

5. The method according to claim 4, characterized in that The step of determining the duty cycle of the DC load shedding Chopper device according to the measured value of the DC bus voltage, the load shedding input threshold value, and the load shedding cut-out threshold value of the grid-side Chopper control strategy includes: When the measured value of the DC bus voltage is greater than the load shedding input threshold, the duty cycle of the DC load shedding Chopper device is 1; When the measured value of the DC bus voltage is less than the load unloading cut-out threshold, the duty cycle of the DC unloading Chopper device is 0; When the measured value of the DC bus voltage is less than or equal to the load shedding input threshold and greater than or equal to the load shedding cut-out threshold, the duty cycle of the DC load shedding Chopper device is D.

6. The method according to claim 5, characterized in that The calculation formula of the duty cycle D is as follows: Where U dc is the measured value of DC bus voltage, is the DC bus voltage reference value, ΔU dcMax It is the DC bus voltage deviation value when the load is fully unloaded.

7. The method according to claim 6, characterized in that The controlling of the DC unloading Chopper device based on the duty cycle to achieve high voltage ride through of the full power converter includes: When the measured value of the DC bus voltage is greater than the load shedding input threshold, controlling the power electronic switch in the DC load shedding Chopper device to close with a duty cycle of 1; When the measured value of the DC bus voltage is less than the load unloading cut-out threshold, the power electronic switch in the DC unloading Chopper device is controlled to be turned off with a duty cycle of; When the measured value of the DC bus voltage is less than or equal to the load shedding input threshold and greater than or equal to the load shedding cut-out threshold, the duty cycle of the DC load shedding Chopper device is controlled to be D.

8. A high voltage ride through bus voltage control system for a full power converter, characterized in that: The system comprises: An acquisition module is used to connect a DC load unloading Chopper device to the DC side of the full-power converter and acquire the DC bus voltage of the power grid in real time; A determination module, used for obtaining a measured value of the DC bus voltage of the power grid when a sudden rise fault occurs in the DC bus voltage, and determining a load shedding input threshold and a load shedding cut-out threshold of a grid-side Chopper control strategy according to the measured value of the DC bus voltage; A control module is used to determine the duty cycle of the DC load shedding Chopper device according to the actual measured value of the DC bus voltage, the load shedding input threshold and the load shedding cut-out threshold of the grid-side Chopper control strategy, and control the DC load shedding Chopper device based on the duty cycle to achieve high voltage ride-through of the full-power converter.

9. An electronic device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method according to any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

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