Converter DC bus voltage control device and method based on hysteresis control

Abstract

The invention provides a converter DC bus voltage control device and method based on hysteresis control, and relates to the technical field of converter control, and the device comprises an information collection module which is used for collecting the grid-connected point voltage of a target wind turbine generator and the rotating speed of a generator; the data analysis module is used for determining the converter operation state of the target wind turbine generator converter according to the grid-connected point voltage and determining the generator operation state of the target wind turbine generator according to the generator rotating speed; the control module is used for sending the operation state of the converter and the operation state of the generator to a main control system of the converter; receiving a target voltage of a converter DC bus determined by the main control system according to the converter operation state and / or the generator operation state, and generating a voltage control instruction of the target voltage; and the execution module is used for responding to the voltage control instruction and controlling the bus voltage of the direct-current bus of the converter to be switched into the target voltage. The safe and stable operation of the wind turbine generator can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of converter control, and in particular to a converter DC bus voltage control device based on hysteresis control, a converter DC bus voltage control method based on hysteresis control, and a computer-readable storage medium. Background Art

[0002] The installed capacity of wind power and photovoltaic power generation in my country has grown rapidly. At present, my country's clean energy power generation capacity accounts for 58.2% of the total installed capacity, and the newly added clean energy power generation accounts for more than half of the total social electricity consumption increase. Among them, the newly added photovoltaic installed capacity increased by 30.7% year-on-year, and the newly added wind power installed capacity increased by 12.4% year-on-year. Due to the rich wind resources in my country, wind power generation technology has been widely used. In recent years, with the expansion of wind power access scale, the frequent off-grid accidents of wind turbines after faults have become the core constraint restricting the scale of wind turbine grid connection. Among them, the reasons for off-grid after wind turbine faults include but are not limited to insufficient low voltage ride-through capability, poor reactive power regulation capability of the unit, and the protection settings of the wind turbine are inconsistent with the adaptability of the grid. Since wind turbines are typical grid voltage-sensitive new energy power generation equipment, they need to have the ability to operate at low voltage without being off-grid during faults during the process of low voltage and high voltage ride-through of wind turbines, and the constant voltage on the DC side is an important prerequisite for wind turbines to have reliable fault ride-through capability. Since wind turbine power cannot change suddenly, DC capacitors are key equipment for balancing the unbalanced power of sources and loads. The coordination of DC voltage control with high and low voltage ride-through is the core technology for achieving reliable ride-through of wind turbines after faults. However, there have been many wind turbine off-grid accidents caused by the mismatch between DC voltage control and the high and low voltage ride-through process during faults. Therefore, it is urgent to propose a DC voltage control optimization method that takes into account both the DC bus voltage constancy and the reliable ride-through requirements of wind power high and low voltage ride-through, so as to achieve reliable ride-through during wind turbine faults. Summary of the invention

[0003] The purpose of the embodiments of the present application is to provide a converter DC bus voltage control device based on hysteresis control, a converter DC bus voltage control method based on hysteresis control and a computer-readable storage medium to solve the above problems.

[0004] In order to achieve the above-mentioned object, the first aspect of the present application provides a converter DC bus voltage control device based on hysteresis control, comprising: Information collection module, used to collect the grid connection point voltage and generator speed of the target wind turbine in real time; A data analysis module, configured to determine a converter operation state of the target wind turbine converter according to the grid connection point voltage, wherein the converter operation state includes a normal operation state or a fault voltage ride-through state, and determine a generator operation state of the target wind turbine according to the generator speed; A control module, used for sending the operating state of the converter and the operating state of the generator to the main control system of the converter; and receiving a voltage control instruction for generating the target voltage by the main control system to determine the target voltage of the DC bus of the converter according to the operating state of the converter and / or the operating state of the generator; An execution module is used to control the bus voltage of the DC bus of the converter to switch to the target voltage in response to the voltage control instruction.

[0005] Optionally, the information collection module includes: A voltage sensor disposed at the grid connection point of the target wind turbine generator set is used to collect the grid connection point voltage of the target wind turbine generator set; The rotation speed sensor arranged on the target wind turbine group is used to collect the generator rotation speed of the target wind turbine group.

[0006] Optionally, the fault voltage ride-through state includes a low voltage ride-through state and a high voltage ride-through state; determining the converter operation state of the target wind turbine converter according to the grid connection point voltage includes: If the grid connection point voltage is not less than the first voltage value, and the grid connection point voltage is not greater than the second voltage value, determining that the converter operation state of the target wind turbine converter is a normal operation state; If the grid connection point voltage is less than the first voltage value, the converter operation state of the target wind turbine converter is determined to be a low voltage ride-through state; if the grid connection point voltage is greater than the second voltage value, the converter operation state of the target wind turbine converter is determined to be a high voltage ride-through state; Wherein, the first voltage value is smaller than the second voltage value.

[0007] Optionally, determining the generator operating state of the target wind turbine generator set according to the generator speed includes: If the generator speed is not less than the first speed value, and the generator speed is not greater than the second speed value, determining that the generator operation state of the target wind turbine group is a normal speed state; If the generator speed is less than the first speed value, or the generator speed is greater than the second speed value, determining that the generator operation state of the target wind turbine group is an abnormal speed state; The first speed value is smaller than the second speed value.

[0008] Optionally, determining a target voltage of the converter DC bus according to the converter operating state and / or the generator operating state includes: If the converter is in a normal operating state and the generator is in a normal speed state, determining that the current voltage of the converter DC bus is the target voltage; If the operating state of the converter is a normal operating state, and the operating state of the generator is an abnormal speed state, the target voltage of the DC bus of the converter is determined according to the speed of the generator.

[0009] Optionally, determining a target voltage of the DC bus of the converter according to the generator speed includes: If the generator speed is less than the first speed value, a predetermined third voltage value is used as the target voltage; If the generator speed is greater than the second speed value, a predetermined fourth voltage value is used as the target voltage; Wherein, the third voltage value is smaller than the fourth voltage value.

[0010] Optionally, determining a target voltage of the converter DC bus according to the converter operating state and / or the generator operating state includes: If the operating state of the converter is a low voltage ride-through state, a predetermined fifth voltage value is used as the target voltage; If the operating state of the converter is a high voltage ride-through state, a predetermined sixth voltage value is used as the target voltage; Wherein, the fifth voltage value is lower than the sixth voltage value.

[0011] A second aspect of the present application provides a method for controlling a DC bus voltage of a converter based on hysteresis control, which is applied to a control module of the above-mentioned DC bus voltage control device of a converter based on hysteresis control, and the method comprises: Sending the converter operation status and generator operation status from the data analysis module to the main control system of the converter, and receiving the target voltage of the converter DC bus determined by the main control system according to the converter operation status and / or the generator operation status, and generating a voltage control instruction of the target voltage; wherein the converter operation status is determined by the data analysis module according to the grid connection point voltage collected by the information collection module, and the generator operation status is determined by the data analysis module according to the generator speed collected by the information collection module; The voltage control instruction is sent to an execution module, so that the bus voltage of the DC bus of the converter is controlled by the execution module to switch to the target voltage.

[0012] In a third aspect of the present application, a converter DC bus voltage control device based on hysteresis control is provided, and the converter DC bus voltage control method based on hysteresis control is applied. The device comprises: The data transmission module is configured to send the converter operation status and the generator operation status from the data analysis module to the main control system of the converter, and receive the target voltage of the converter DC bus determined by the main control system according to the converter operation status and / or the generator operation status, and generate a voltage control instruction of the target voltage; wherein the converter operation status is determined by the data analysis module according to the grid connection point voltage collected by the information collection module, and the generator operation status is determined by the data analysis module according to the generator speed collected by the information collection module; The voltage control module is configured to send the voltage control instruction to the execution module, so as to control the bus voltage of the DC bus of the converter to switch to the target voltage through the execution module.

[0013] A fourth aspect of the present application provides a computer-readable storage medium storing a computer program which, when executed by a processor, causes the processor to execute the above-mentioned method for controlling the DC bus voltage of a converter based on hysteresis control.

[0014] The embodiments provided in this application have the following beneficial effects: The present application determines the operating status of the converter by monitoring the real-time changes in the grid voltage, and determines the operating range of the converter DC bus voltage by detecting the generator speed range, thereby realizing intelligent control and switching of the bus voltage; through intelligent control of the converter DC bus voltage, the present application can reduce the probability of unit failure and shutdown caused by the bus voltage mistakenly entering the high or low voltage crossing state within the converter hysteresis control range, thereby improving the safe and stable operation of the wind turbine.

[0015] Other features and advantages of the embodiments or implementations of the present application will be described in detail in the subsequent specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the following specific implementations, they are used to explain the embodiments of the present application, but do not constitute a limitation on the embodiments of the present application. In the accompanying drawings: Figure 1 A schematic diagram of the structure of a converter DC bus voltage control device based on hysteresis control according to an embodiment of the present application is shown schematically; Figure 2 The voltage control logic diagram of the embodiment of the present application is schematically shown; Figure 3 A method flow chart schematically shows a method for controlling a DC bus voltage of a converter based on hysteresis control according to an embodiment of the present application; Figure 4A schematic block diagram of another converter DC bus voltage control device based on hysteresis control according to an embodiment of the present application is schematically shown; Figure 5 A schematic diagram of the structure of a terminal device according to an embodiment of the present application is shown schematically.

[0017] Description of Reference Numerals 10-terminal device, 100-processor, 101-memory, 102-computer program. DETAILED DESCRIPTION

[0018] The specific implementation of the embodiment of the present application is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the embodiment of the present application, and is not used to limit the embodiment of the present application.

[0019] It is understandable that constant DC voltage is the basic constraint for achieving reliable ride-through during wind turbine faults. Currently, the existing technology ignores the problem of wind turbine fault ride-through failure caused by the DC voltage control switching process, and does not optimize the unit's continuous high and low ride-through and grid-off shutdown accidents caused by improper coordination between the converter DC bus voltage control switching and the converter high and low ride-through. In order to solve the above problems, Figure 1 As shown, the first aspect of the present application provides a converter DC bus voltage control device based on hysteresis control, comprising: Information collection module, used to collect the grid connection point voltage and generator speed of the target wind turbine in real time; A data analysis module is used to determine the converter operation state of the target wind turbine converter according to the grid connection point voltage, the converter operation state includes a normal operation state or a fault voltage ride-through state, and to determine the generator operation state of the target wind turbine according to the generator speed; A control module, used for sending the operating status of the converter and the operating status of the generator to the main control system of the converter; and receiving a voltage control instruction for the main control system to determine the target voltage of the converter DC bus according to the operating status of the converter and / or the operating status of the generator, and to generate the target voltage; The execution module is used to control the bus voltage of the DC bus of the converter to switch to the target voltage in response to the voltage control instruction.

[0020] In this way, the present application determines the operating status of the converter by monitoring the real-time changes in the grid voltage, and determines the operating range of the converter DC bus voltage by detecting the generator speed range, thereby realizing intelligent control and switching of the bus voltage; through intelligent control of the converter DC bus voltage, the present application can reduce the probability of unit failure and shutdown caused by the bus voltage mistakenly entering the high or low voltage crossing state within the converter hysteresis control range, thereby improving the safe and stable operation of the wind turbine set.

[0021] Among them, the voltage control device of the present application can be directly installed in the converter control cabinet of the target wind turbine group, and the voltage control device of the present application also includes a power module and a communication module. Among them, the information acquisition module transmits the collected electrical quantities such as the grid voltage and the generator speed to the data analysis module; the control module receives the voltage state signal, judges whether the unit is in normal operation or enters a low-through or high-through state, and performs logical judgment and outputs a response control signal through the speed state signal; the industrial control component, namely the execution module, is used to execute the control signal issued by the control module to control the output level of the converter bus voltage; the power supply component, namely the power supply module, is used to supply power to the entire control device; the communication module is used to send the command signal transmitted by the control module to the main control system, and the main control system judges the current converter operation state quantity and returns the control module related control signal to realize the real-time monitoring and switching of the converter bus voltage. It can be understood that each module in the present application can be implemented using existing hardware, for example, the existing MCU, CPU, communication chip, etc. are used to implement the functions of the above modules, wherein the data analysis module, the control module, etc. can be different functional units integrated on the same control chip; the execution module is an execution component for executing voltage control, for example, the execution component can be a power semiconductor device such as IGBT, or the execution module can be the original inverter of the target wind turbine converter, and the on and off time of the corresponding IGBT in the inverter is controlled by the control signal of the control module, that is, the existing PWM control adjusts the output voltage of the converter DC bus, wherein the control of the output voltage of the converter DC bus is a prior art and is not limited here.

[0022] In the present application, the information acquisition module includes a voltage sensor arranged at the grid-connected point of the target wind turbine group, which is used to collect the grid-connected point voltage of the target wind turbine group; and a speed sensor arranged on the tail of the generator of the target wind turbine group, which is used to collect the generator speed of the target wind turbine group, and send the collected grid-connected point voltage and generator speed to the data analysis module in real time.

[0023] The data analysis module determines the current operating state of the converter and the current operating state of the generator according to the received grid connection point voltage and generator speed; wherein the fault voltage ride-through state includes the low voltage ride-through state and the high voltage ride-through state, such as Figure 2 As shown, the converter operation state of the target wind turbine converter is determined according to the grid connection point voltage, including: If the grid connection point voltage is not less than the first voltage value, and the grid connection point voltage is not greater than the second voltage value, it is determined that the converter operation state of the target wind turbine converter is a normal operation state, wherein the first voltage value is less than the second voltage value; for example, the first voltage value is set to 0.9UN, and the second voltage value is set to 1.1UN, wherein UN is the rated voltage of the grid, and if the grid connection point voltage value is satisfy When the inverter is within the range of ; If the grid connection point voltage is less than the first voltage value, the converter operation state of the target wind turbine converter is determined to be a low voltage ride-through state; if the grid connection point voltage is greater than the second voltage value, the converter operation state of the target wind turbine converter is determined to be a high voltage ride-through state; for example, if the grid connection point voltage does not meet When the inverter is in the fault voltage ride-through state, the state is recorded as ,in, Indicates the current operating status of the converter. Specifically, if the current grid-connected point voltage meets When the inverter is in the low voltage ride-through state, the inverter is judged to be in the low voltage ride-through state, and the low voltage ride-through state flag of the inverter is configured as ;when and Dissatisfied When U>1.1UN, the converter is judged to be in the high voltage ride-through state, and its high voltage ride-through state flag is configured as ,in, Indicates the converter fault voltage status.

[0024] In the present application, the generator operating state of the target wind turbine is determined based on the generator speed, including: if the generator speed is not less than the first speed value, and the generator speed is not greater than the second speed value, the generator operating state of the target wind turbine is determined to be a normal speed state; if the generator speed is less than the first speed value, or the generator speed is greater than the second speed value, the generator operating state of the target wind turbine is determined to be an abnormal speed state; wherein the first speed value is less than the second speed value. For example, the first speed value is set to rL, the second speed value is set to rH, and r is the current generator speed. If the generator speed value is rL≤r≤rH, it is determined that the generator speed is within the normal control range, that is, it is in the normal speed state. At this time, the generator operating state flag is configured as Otherwise, the generator operation state is determined to be an abnormal speed state. Specifically, if the generator speed is r<rL, the generator operation state flag is configured as ; If the generator speed value is higher than the upper limit of the speed range, that is, r>rH, the generator operation status flag is configured as a status signal ,in, Indicates the generator speed range signal.

[0025] The original main control system of the converter receives ,and The target voltage of the DC bus of the converter is determined according to the operating state of the converter and / or the operating state of the generator, and different voltage command signals are fed back to the control module, so that the control module controls the switching of the DC bus voltage according to the different voltage command signals. If the converter is in normal operation and the generator is in normal speed, the current voltage of the converter DC bus is determined to be the target voltage; that is, when and When the original main control system of the converter feeds back the signal of not adjusting the DC bus voltage to the control module, the control module controls the output voltage value of the actuator components. , indicating that the current DC bus voltage value remains unchanged; If the converter is in normal operation and the generator is in abnormal speed, the target voltage of the converter DC bus is determined according to the generator speed. Specifically, if the generator speed is less than the first speed value, the predetermined third voltage value is used as the target voltage; if the generator speed is greater than the second speed value, the predetermined fourth voltage value is used as the target voltage; wherein the third voltage value is less than the fourth voltage value. For example, when and When the inverter main control system feeds back the low speed bus voltage signal to the control module, the control module controls the output voltage value , indicating that the DC bus voltage switches to the low-speed bus given voltage value; when and When the main control system feeds back the DC bus voltage normal signal to the control module, the control module switches to the normal bus voltage setting value. ; Among them, U0 identifies the third voltage value, U1 identifies the fourth voltage value, and both U0 and U1 can be predetermined and configured.

[0026] In the present application, the target voltage of the converter DC bus is determined according to the converter operation state and / or the generator operation state, including: if the converter operation state is a low voltage ride-through state, a predetermined fifth voltage value is used as the target voltage; if the converter operation state is a high voltage ride-through state, a predetermined sixth voltage value is used as the target voltage; wherein the fifth voltage value is lower than the sixth voltage value. For example, when and When the original main control system of the converter feeds back the low bus voltage signal to the control module, the control module controls the output bus voltage to , indicating that the DC bus voltage switches to the low-pass given value, that is, the fifth voltage value; when and When the inverter main control system feeds back the high-voltage bus voltage signal to the control module, the control module controls the output DC bus voltage to , indicating that the DC bus voltage switches to the high-pass given value, that is, the sixth voltage value.

[0027] Finally, the bus voltage reference value obtained by the control in the above steps is merged into the original DC voltage control system of the converter, so as to realize the bus voltage switching control of the converter DC bus. It can be understood that the obtained bus voltage reference value is merged into the original DC voltage control system of the converter, which can be to apply the corresponding voltage control instruction to the voltage control system of the original converter, so as to realize the control of the DC bus output voltage by controlling the conduction and disconnection of the power semiconductor devices such as IGBT of the original converter; or, it can be to directly control the power semiconductor devices of the original converter to realize the control of the DC bus output voltage, which is not limited here.

[0028] like Figure 3 As shown, the second aspect of the present application provides a method for controlling a DC bus voltage of a converter based on hysteresis control, which is applied to the control module of the above-mentioned DC bus voltage control device of the converter based on hysteresis control, and the method includes: The converter operation status and the generator operation status from the data analysis module are sent to the main control system of the converter, and the receiving main control system determines the target voltage of the converter DC bus according to the converter operation status and / or the generator operation status, and generates a voltage control instruction of the target voltage; wherein the converter operation status is determined by the data analysis module according to the grid connection point voltage collected by the information collection module, and the generator operation status is determined by the data analysis module according to the generator speed collected by the information collection module; The voltage control instruction is sent to the execution module, so as to control the bus voltage of the DC bus of the converter to be switched to the target voltage through the execution module.

[0029] like Figure 4 As shown, the third aspect of the present application provides a converter DC bus voltage control device based on hysteresis control, applying the above converter DC bus voltage control method based on hysteresis control, the device includes: The data transmission module is configured to send the converter operation status and the generator operation status from the data analysis module to the main control system of the converter, and to receive the target voltage of the converter DC bus determined by the main control system according to the converter operation status and / or the generator operation status, and to generate a voltage control instruction of the target voltage; wherein the converter operation status is determined by the data analysis module according to the grid connection point voltage collected by the information collection module, and the generator operation status is determined by the data analysis module according to the generator speed collected by the information collection module; The voltage control module is configured to send a voltage control instruction to the execution module, so as to control the bus voltage of the DC bus of the converter to switch to a target voltage through the execution module.

[0030] The technicians in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.

[0031] A fourth aspect of the present application provides a computer-readable storage medium storing a computer program which, when executed by a processor, causes the processor to execute the above-mentioned method for controlling the DC bus voltage of a converter based on hysteresis control.

[0032] In a fifth aspect of the present application, a terminal device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the above-mentioned wind turbine pitch control method when executing the computer program.

[0033] like Figure 5 FIG. 1 is a schematic diagram of a terminal device provided in an embodiment of the present application. Figure 5 As shown, the terminal device 10 of this embodiment includes: a processor 100, a memory 101, and a computer program 102 stored in the memory 101 and executable on the processor 100. When the processor 100 executes the computer program 102, the steps in the above method embodiment are implemented. Alternatively, when the processor 100 executes the computer program 102, the functions of each module / unit in the above device embodiments are implemented.

[0034] Exemplarily, the computer program 102 may be divided into one or more modules / units, one or more modules / units are stored in the memory 101, and are executed by the processor 100 to complete the present application. One or more modules / units may be a series of computer program instruction segments capable of completing specific functions, and the instruction segments are used to describe the execution process of the computer program 102 in the terminal device 10.

[0035] The terminal device 10 may be a computing device such as a desktop computer, a notebook, a PDA, or a cloud server. The terminal device 10 may include, but is not limited to, a processor 100 and a memory 101. Those skilled in the art will appreciate that Figure 5 It is only an example of the terminal device 10 and does not constitute a limitation of the terminal device 10. It may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, the terminal device may also include input and output devices, network access devices, buses, etc.

[0036] The processor 100 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or the processor may be any conventional processor, etc.

[0037] The memory 101 may be an internal storage unit of the terminal device 10, such as a hard disk or memory of the terminal device 10. The memory 101 may also be an external storage device of the terminal device 10, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card (FlashCard), etc. equipped on the terminal device 10. Further, the memory 101 may also include both an internal storage unit of the terminal device 10 and an external storage device. The memory 101 is used to store computer programs and other programs and data required by the terminal device 10. The memory 101 may also be used to temporarily store data that has been output or is to be output.

[0038] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0039] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0040] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included within the scope of the claims of the present application.

Claims

1. A converter DC bus voltage control device based on hysteresis control, characterized in that: include: Information collection module, used to collect the grid connection point voltage and generator speed of the target wind turbine in real time; A data analysis module, configured to determine a converter operation state of the target wind turbine converter according to the grid connection point voltage, wherein the converter operation state includes a normal operation state or a fault voltage ride-through state, and determine a generator operation state of the target wind turbine according to the generator speed; A control module, used for sending the operating status of the converter and the operating status of the generator to the main control system of the converter; and receiving a target voltage of the DC bus of the converter determined by the main control system according to the operating state of the converter and / or the operating state of the generator, and generating a voltage control instruction of the target voltage; An execution module is used to control the bus voltage of the DC bus of the converter to switch to the target voltage in response to the voltage control instruction.

2. The converter DC bus voltage control device based on hysteresis control according to claim 1, characterized in that: The information collection module comprises: A voltage sensor disposed at the grid connection point of the target wind turbine generator set is used to collect the grid connection point voltage of the target wind turbine generator set; The rotation speed sensor arranged on the target wind turbine group is used to collect the generator rotation speed of the target wind turbine group.

3. The converter DC bus voltage control device based on hysteresis control according to claim 1, characterized in that: The fault voltage ride-through state includes a low voltage ride-through state and a high voltage ride-through state; determining the converter operation state of the target wind turbine converter according to the grid connection point voltage includes: If the grid connection point voltage is not less than the first voltage value, and the grid connection point voltage is not greater than the second voltage value, determining that the converter operation state of the target wind turbine converter is a normal operation state; If the grid connection point voltage is less than the first voltage value, the converter operation state of the target wind turbine converter is determined to be a low voltage ride-through state; if the grid connection point voltage is greater than the second voltage value, the converter operation state of the target wind turbine converter is determined to be a high voltage ride-through state; Wherein, the first voltage value is smaller than the second voltage value.

4. The converter DC bus voltage control device based on hysteresis control according to claim 3, characterized in that: Determining the generator operating state of the target wind turbine generator set according to the generator speed includes: If the generator speed is not less than the first speed value, and the generator speed is not greater than the second speed value, determining that the generator operation state of the target wind turbine group is a normal speed state; If the generator speed is less than the first speed value, or the generator speed is greater than the second speed value, determining that the generator operation state of the target wind turbine group is an abnormal speed state; The first speed value is smaller than the second speed value.

5. The converter DC bus voltage control device based on hysteresis control according to claim 4, characterized in that: Determining a target voltage of the converter DC bus according to the converter operating state and / or the generator operating state includes: If the converter is in a normal operating state and the generator is in a normal speed state, determining that the current voltage of the converter DC bus is the target voltage; If the operating state of the converter is a normal operating state, and the operating state of the generator is an abnormal speed state, the target voltage of the DC bus of the converter is determined according to the speed of the generator.

6. The converter DC bus voltage control device based on hysteresis control according to claim 5, characterized in that: Determining a target voltage of the DC bus of the converter according to the generator speed includes: If the generator speed is less than the first speed value, a predetermined third voltage value is used as the target voltage; If the generator speed is greater than the second speed value, a predetermined fourth voltage value is used as the target voltage; Wherein, the third voltage value is smaller than the fourth voltage value.

7. The converter DC bus voltage control device based on hysteresis control according to claim 4, characterized in that: Determining a target voltage of the converter DC bus according to the converter operating state and / or the generator operating state includes: If the operating state of the converter is a low voltage ride-through state, a predetermined fifth voltage value is used as the target voltage; If the operating state of the converter is a high voltage ride-through state, a predetermined sixth voltage value is used as the target voltage; Wherein, the fifth voltage value is lower than the sixth voltage value.

8. A method for controlling a DC bus voltage of a converter based on hysteresis control, applied to a control module of a DC bus voltage control device of a converter based on hysteresis control as claimed in any one of claims 1 to 7, characterized in that: The method comprises: Sending the converter operation status and generator operation status from the data analysis module to the main control system of the converter, and receiving the target voltage of the converter DC bus determined by the main control system according to the converter operation status and / or the generator operation status, and generating a voltage control instruction of the target voltage; wherein the converter operation status is determined by the data analysis module according to the grid connection point voltage collected by the information collection module, and the generator operation status is determined by the data analysis module according to the generator speed collected by the information collection module; The voltage control instruction is sent to an execution module, so that the bus voltage of the DC bus of the converter is controlled by the execution module to switch to the target voltage.

9. A converter DC bus voltage control device based on hysteresis control, using the converter DC bus voltage control method based on hysteresis control according to claim 8, characterized in that: The device comprises: The data transmission module is configured to send the converter operation status and the generator operation status from the data analysis module to the main control system of the converter, and receive the target voltage of the converter DC bus determined by the main control system according to the converter operation status and / or the generator operation status, and generate a voltage control instruction of the target voltage; wherein the converter operation status is determined by the data analysis module according to the grid connection point voltage collected by the information collection module, and the generator operation status is determined by the data analysis module according to the generator speed collected by the information collection module; The voltage control module is configured to send the voltage control instruction to the execution module, so as to control the bus voltage of the DC bus of the converter to switch to the target voltage through the execution module.

10. A computer-readable storage medium, characterized in that: A computer program is stored which, when executed by a processor, causes the processor to execute the method for controlling the DC bus voltage of a converter based on hysteresis control as claimed in claim 8.

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