Transient self-adaptive control method and device for matching control type direct-driven wind turbine generator

Abstract

The invention belongs to the technical field of power grid control, and provides a transient self-adaptive control method and device for a matching control type direct-driven wind turbine generator. Phase locking is conducted on the matching control type direct-driven wind turbine generator through an unloading circuit of the matching control type direct-driven wind turbine generator; when the matching control type direct-driven wind turbine generator set is in the fault period, the reactive power of the matching control type direct-driven wind turbine generator set is determined in real time according to the voltage of the grid-connected point of the matching control type direct-driven wind turbine generator set; and suppressing a current transient component of the matching control type direct-driven wind turbine generator according to the pre-generated virtual resistance. The embodiment of the invention provides a matching control type direct-driven wind turbine generator transient adaptive control method considering current limiting and reactive voltage active support.

Description

Technical Field

[0001] The present application belongs to the field of power grid control technology, and in particular to the field of grid-building new energy unit control technology, and in particular to a transient adaptive control method and device for a matching control type direct-drive wind turbine unit. Background Art

[0002] At present, with the gradual promotion and application of grid-type new energy units and energy storage, there are more and more devices that can be actively supported in the station, and each device shows different principles and response characteristics. Grid-type control can make the converter have external characteristics similar to those of synchronous generators, which can effectively solve the problems of weak inertia and low short-circuit ratio faced by the "double high" power system. However, the instantaneous component of the short-circuit current of the grid-type converter can reach 4 to 10 times the rated current when the grid fails, far exceeding its tolerance of 1.2 to 1.5 times the rated current. At present, additional current control loops are mostly used to limit it. Limited by the control bandwidth, the current unit still has the problem of short-term impact current exceeding the limit under grid faults. In addition, the short-circuit current and voltage support affect each other, which is not considered under grid faults. Summary of the invention

[0003] The transient adaptive control method and device of the matching control type direct-drive wind turbine provided by the present invention aims to at least solve the technical problem of large-scale grid disconnection of new energy caused by insufficient active frequency and voltage support capacity in the prior art.

[0004] In order to solve the technical problems in the background technology of this application, the present invention provides the following technical solutions:

[0005] In a first aspect, the present invention provides a transient adaptive control method for a matching control type direct-drive wind turbine generator set, the method comprising:

[0006] When the matching control type direct-drive wind turbine set fails, the matching control type direct-drive wind turbine set is phase-locked through the unloading circuit of the matching control type direct-drive wind turbine set;

[0007] When the matching control type direct-drive wind turbine set is in a fault period, determining the reactive power of the matching control type direct-drive wind turbine set in real time according to the voltage of the grid connection point of the matching control type direct-drive wind turbine set; and

[0008] The current transient component of the matching control type direct-drive wind turbine generator set is suppressed according to the pre-generated virtual resistance.

[0009] In some embodiments of the present application, phase locking is performed on the matching control type direct-drive wind turbine generator set, including:

[0010] The DC voltage synchronization link of the matching control type direct-drive wind turbine generator set is cut off through the unloading circuit.

[0011] In some embodiments of the present application, a transient adaptive control method for a matching control type direct-drive wind turbine generator system further includes:

[0012] When the DC voltage of the matching control type direct-drive wind turbine set is greater than the detection threshold of the DC voltage, and the fault voltage of the matching control type direct-drive wind turbine set is less than the detection threshold of the fault voltage, it is determined that the matching control type direct-drive wind turbine set has a fault.

[0013] In some embodiments of the present application, the reactive power of the matching control type direct-drive wind turbine generator set is determined in real time according to the voltage of the grid connection point of the matching control type direct-drive wind turbine generator set, including:

[0014] Determining in real time the nominal value of the reactive current corresponding to the reactive power according to the per-unit value of the voltage at the grid connection point;

[0015] The nominal value of the reactive power instruction during the fault period is determined in real time according to the nominal value of the d-axis component of the voltage at the grid connection point.

[0016] In some embodiments of the present application, the step of generating the virtual resistance includes:

[0017] The virtual resistor is determined according to a magnitude relationship between an output current of a grid-side inverter of the matching control type direct-drive wind turbine group and a threshold value of a starting current of the virtual resistor.

[0018] In a second aspect, the present invention provides a transient adaptive control device for a matching control type direct-drive wind turbine generator set, the device comprising:

[0019] A unit phase locking module, used for performing phase locking on the matching control type direct-drive wind turbine unit through the unloading circuit of the matching control type direct-drive wind turbine unit when a fault occurs to the matching control type direct-drive wind turbine unit;

[0020] A reactive power real-time update module, used for determining the reactive power of the matching-controlled direct-drive wind turbine set in real time according to the voltage of the grid-connected point of the matching-controlled direct-drive wind turbine set when the matching-controlled direct-drive wind turbine set is in a fault period; and

[0021] The current transient suppression module is used to suppress the current transient component of the matching control type direct-drive wind turbine group according to the pre-generated virtual resistance.

[0022] In some embodiments of the present application, the unit phase locking module includes:

[0023] The synchronization link cutting unit is used to cut off the DC voltage synchronization link of the matching control type direct-drive wind turbine set through the unloading circuit.

[0024] In some embodiments of the present application, a transient adaptive control device for a matching control type direct-drive wind turbine generator system further includes:

[0025] The unit fault judgment module is used to judge that the matching control type direct-drive wind turbine unit has a fault when the DC voltage of the matching control type direct-drive wind turbine unit is greater than the detection threshold of the DC voltage and the fault voltage of the matching control type direct-drive wind turbine unit is less than the detection threshold of the fault voltage.

[0026] In some embodiments of the present application, the reactive power real-time update module includes:

[0027] A reactive current nominal value determination unit, used to determine the nominal value of the reactive current corresponding to the reactive power in real time according to the per unit value of the voltage at the grid connection point;

[0028] The command nominal value determination unit is used to determine the nominal value of the reactive power command of the reactive power during the fault period in real time according to the nominal value of the d-axis component of the voltage of the grid connection point.

[0029] In some embodiments of the present application, a transient adaptive control device for a matching control type direct-drive wind turbine generator system further includes:

[0030] A virtual resistance generating module, used to generate the virtual resistance, the virtual resistance generating module comprising:

[0031] The virtual resistance generating unit is used to determine the virtual resistance according to the magnitude relationship between the output current of the grid-side inverter of the matching control type direct-drive wind turbine group and the threshold value of the starting current of the virtual resistance.

[0032] In a third aspect, the present invention provides a computer program product, including a computer program / instruction, which, when executed by a processor, implements the steps of a transient adaptive control method for a matching control type direct-drive wind turbine.

[0033] In a fourth aspect, the present invention 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 processor implements the steps of a transient adaptive control method for a matching control type direct-drive wind turbine group.

[0034] In a fifth aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of a transient adaptive control method for a matching control type direct-drive wind turbine generator system.

[0035] From the above description, it can be seen that an embodiment of the present invention provides a transient adaptive control method and device for a matching-controlled direct-drive wind turbine group. The corresponding transient adaptive control method for a matching-controlled direct-drive wind turbine group includes: first, when a fault occurs in the matching-controlled direct-drive wind turbine group, the matching-controlled direct-drive wind turbine group is phase-locked by the unloading circuit of the matching-controlled direct-drive wind turbine group; then, when the matching-controlled direct-drive wind turbine group is in a fault period, the reactive power of the matching-controlled direct-drive wind turbine group is determined in real time according to the voltage of the grid-connected point of the matching-controlled direct-drive wind turbine group; and finally, the transient component of the current of the matching-controlled direct-drive wind turbine group is suppressed according to the pre-generated virtual resistance.

[0036] The present invention comprehensively considers factors such as the short-circuit current steady-state component, transient component, reactive voltage support and voltage source characteristics, making up for the deficiency of the existing method of suppressing transient impact current without considering voltage support, retaining the voltage source characteristics of the matching control type direct-drive wind turbine, and avoiding the problem of the control strategy being too dependent on system parameters due to the use of voltage vector limiting. At the same time, the parameter design is simple and convenient for engineering practice. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0038] Figure 1 The flow chart of a transient adaptive control method for a matching control type direct-drive wind turbine generator system in an embodiment of the present invention is as follows Figure 1 .

[0039] Figure 2 1 is a flow chart of step 100 of a transient adaptive control method for a matching control type direct-drive wind turbine generator system in an embodiment of the present invention.

[0040] Figure 3 The flow chart of a transient adaptive control method for a matching control type direct-drive wind turbine generator system in an embodiment of the present invention is as follows Figure 2 .

[0041] Figure 4 1 is a flow chart of step 200 of a transient adaptive control method for a matching control type direct-drive wind turbine generator system in an embodiment of the present invention.

[0042] Figure 5 The flow chart of a transient adaptive control method for a matching control type direct-drive wind turbine generator system in an embodiment of the present invention is as follows Figure 3 .

[0043] Figure 6 Schematic diagram of the flow of step 500 of a transient adaptive control method for a matching control type direct-drive wind turbine generator system in an embodiment of the present invention.

[0044] Figure 7 It is a flow chart of a transient adaptive control method of a matching control type direct-drive wind turbine generator set in a specific implementation manner of the present invention.

[0045] Figure 8 It is a control block diagram of a transient adaptive control method for a matching control type direct-drive wind turbine generator set in a specific implementation manner of the present invention.

[0046] Fig. 9 It is a fault detection control block diagram in a specific implementation manner of the present invention.

[0047] Fig.10 It is a control block diagram of phase locking in a specific implementation manner of the present invention.

[0048] Fig.11 It is a block diagram of adaptive reactive power switching control in a specific implementation manner of the present invention.

[0049] Fig.12 It is a topological diagram of a 5MW matching control type direct-drive wind turbine model in a specific implementation manner of the present invention.

[0050] Fig.13 1 and 2 are waveforms of current, reactive power and synchronous frequency of strategy I in a specific implementation manner of the present invention.

[0051] Fig.14 1 and 2 are waveforms of current, reactive power and synchronous frequency of Strategy II in a specific implementation manner of the present invention.

[0052] Fig.15 1 and 2 are waveforms of current, reactive power and synchronous frequency of Strategy III in a specific implementation manner of the present invention.

[0053] Fig.16 1 and 2 are waveforms of current, reactive power and synchronous frequency of Strategy IV in a specific implementation manner of the present invention.

[0054] Fig.17 It is a schematic diagram of current waveform comparison in the scenarios where the short circuit ratios are 4 and 3 in a specific implementation manner of the present invention.

[0055] Fig.18 It is a schematic diagram of current waveform comparison in the scenarios where the short circuit ratios are 2 and 1 in a specific implementation manner of the present invention.

[0056] Fig.19It is the voltage waveform of the grid-connected point that continuously switches between high and low in the specific implementation manner of the present invention.

[0057] Fig. 20 It is the current waveform of the traditional control strategy in the specific implementation of the present invention.

[0058] Fig.21 It is a current waveform of a transient adaptive control strategy of a matching control type direct-drive wind turbine generator set taking into account both current limiting and reactive voltage support in a specific implementation manner of the present invention.

[0059] Fig. 22 It is the corresponding waveform of the single-phase short circuit of the matching control type direct-drive wind turbine system at 5s to 5.5s in the specific implementation manner of the present invention.

[0060] Fig.23 It is the corresponding waveform of the two-phase ground short circuit of the matching control type direct-drive wind turbine system at 5s to 5.5s in the specific implementation manner of the present invention.

[0061] Fig.24 A block diagram of a transient adaptive control device for a matching control type direct-drive wind turbine generator system in an embodiment of the present invention Figure 1 .

[0062] Fig.25 FIG. 1 is a block diagram of a generator set phase locking module 10 in an embodiment of the present invention.

[0063] Fig.26 A block diagram of a transient adaptive control device for a matching control type direct-drive wind turbine generator system in an embodiment of the present invention Figure 2 .

[0064] Fig. 27 FIG. 4 is a block diagram of the reactive power real-time update module 20 in an embodiment of the present invention.

[0065] Fig.28 A block diagram of a transient adaptive control device for a matching control type direct-drive wind turbine generator system in an embodiment of the present invention Figure 3 .

[0066] Fig.29 is a block diagram of the virtual resistance generating module 50 in an embodiment of the present invention.

[0067] Fig.30 FIG. 4 is a schematic diagram of the structure of an electronic device in an embodiment of the present invention. DETAILED DESCRIPTION

[0068] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0069] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take 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 code.

[0070] It should be noted that the terms "including" and "having" in the specification and claims of the present application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices. In the absence of conflict, the embodiments in the present application and the features in the embodiments may be combined with each other. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0071] In the current power grid, synchronous generator sets with autonomous voltage building capabilities are the main body to ensure the synchronous and stable operation of the power system. In recent years, a large number of new energy units have adopted a grid-following control method in which the phase-locked loop passively follows the grid voltage, and do not have the ability to actively support frequency and voltage. After its large-scale replacement of synchronous machines, the basis for maintaining the safe and stable frequency and voltage of the system has been weakened. In recent years, large-scale grid disconnection incidents of new energy have occurred in many places due to insufficient active frequency and voltage support capabilities. By improving the converter control method, the grid-building technology enables new energy units to have the ability to establish grid voltage and frequency, and can be connected to the grid as an equivalent voltage source, and realize active support functions such as inertia response, primary frequency regulation response, and rapid voltage regulation through appropriate control.

[0072] At present, typical grid-forming control strategies mainly include droop control, virtual synchronous generator (VSG) control and matching control (MC). Among them, the matching control converter (MCC) is a grid-forming converter that uses DC capacitor energy to simulate the rotor energy of a synchronous generator. Compared with the VSG control strategy that uses active power-frequency to achieve synchronization, the MC strategy can take into account the control of the DC side voltage and realize DC side voltage control and converter synchronization. MCC only needs to measure the DC bus voltage to achieve autonomous synchronization with the power grid, and can directly provide the equivalent inertia of the system. With the above advantages, the matching control permanent magnet synchronous generator (MC-PMSG) has been tested and verified in many places and has broad application prospects in the future.

[0073] The research on the suppression of transient overcurrent under MC-PMSG fault mainly includes two aspects: current inner loop control and open loop control. In terms of transient current control of grid-connected converters equipped with current inner loop, some literatures switch the converter to current source control mode during the fault period. Although it effectively controls the transient current, it sacrifices its original voltage source characteristics. Some literatures adopt a voltage and current dual closed-loop control structure. By accurately estimating the output current of the inverter and applying it to feedforward control, the transient stability of the inverter can be enhanced. However, the parameter design of this method is complex and the impact current is obvious. There are also literatures that introduce current controllers and virtual admittance mechanisms to suppress transient overcurrent problems for matching controlled wind turbines, but simulations show that this method still has the problem of excessive impact current at the moment of fault and recovery.

[0074] In terms of transient current control of open-loop control type grid-connected converters, some literature uses phasor limiting and virtual resistance technology to effectively limit the current of VSG when the grid is symmetrically short-circuited, but at the cost of artificially reducing power output. Some literature uses dynamic compensation of VSG power angle to achieve current suppression, but because it relies on memory elements, the actual application complexity is relatively high. Some literature uses voltage limiting to limit the steady-state component of transient current, and suppresses instantaneous current shocks by switching nonlinear resistors, but this control strategy still has problems such as excessive dependence on system parameters and limited consideration of voltage support.

[0075] Some of the above methods and ideas can be applied to the transient overcurrent control of MC-PMSG. However, the analysis focuses on a certain characteristic of MC-PMSG, while transient impact current, unstable reactive voltage support, and loss of voltage source characteristics usually occur simultaneously during the transient period. Therefore, the present invention comprehensively considers the above factors, and based on the transient current generation mechanism and the GC0137 reactive voltage support standard, proposes a MC-PMSG transient adaptive control strategy that takes into account both current limiting and reactive voltage active support.

[0076] The embodiment of the present invention provides a specific implementation method of a transient adaptive control method for a matching control type direct-drive wind turbine generator set, see Figure 1 , the method comprising:

[0077] Step 100: When the matching control type direct-drive wind turbine set fails, the matching control type direct-drive wind turbine set is phase-locked through the unloading circuit of the matching control type direct-drive wind turbine set;

[0078] Step 200: when the matching control type direct-drive wind turbine set is in a fault period, determining the reactive power of the matching control type direct-drive wind turbine set in real time according to the voltage of the grid connection point of the matching control type direct-drive wind turbine set; and

[0079] Step 300: suppressing the current transient component of the matching control type direct-drive wind turbine generator system according to the pre-generated virtual resistance.

[0080] From the above description, it can be seen that an embodiment of the present invention provides a transient adaptive control method for a matching-controlled direct-drive wind turbine group, including: first, when a matching-controlled direct-drive wind turbine group fails, the matching-controlled direct-drive wind turbine group is phase-locked by the unloading circuit of the matching-controlled direct-drive wind turbine group; then, when the matching-controlled direct-drive wind turbine group is in a fault period, the reactive power of the matching-controlled direct-drive wind turbine group is determined in real time according to the voltage of the grid-connected point of the matching-controlled direct-drive wind turbine group; and finally, the transient component of the current of the matching-controlled direct-drive wind turbine group is suppressed according to the pre-generated virtual resistance.

[0081] The embodiment of the present invention provides a MC-PMSG transient adaptive control method that takes into account both current limiting and active reactive voltage support.

[0082] Regarding step 100, it should be noted that the effectiveness of the fault detection and phase locking control matching control of the matching control type direct-drive wind turbine group depends on two factors, namely the current operating point and the depth of the grid voltage drop. These two factors determine whether the unloading circuit is activated. When the system enters the fault mode, phase locking is performed to cut off the DC voltage synchronization link.

[0083] For step 200, in order to meet the current limiting and voltage support requirements, adaptive reactive switching control is performed based on the transient current generation mechanism and the GC0137 reactive voltage support standard.

[0084] Step 300 provides an adaptive virtual resistance control strategy, which enables the virtual resistance value to be adjusted linearly with the change of current. The control has a suppressive effect on the transient component of the current and only acts at the moment of fault. The remaining states are automatically cut off from the matching control type direct-drive wind turbine set.

[0085] In some embodiments of the present application, see Figure 2 , the phase locking of the matching control type direct-drive wind turbine set in step 100 includes:

[0086] Step 101: Cutting off the DC voltage synchronization link of the matching control type direct-drive wind turbine generator set through the unloading circuit.

[0087] In some embodiments of the present application, see Figure 3 , a transient adaptive control method for a matching control type direct-drive wind turbine generator set, further comprising:

[0088] Step 400: When the DC voltage of the matching control type direct-drive wind turbine set is greater than the detection threshold of the DC voltage, and the fault voltage of the matching control type direct-drive wind turbine set is less than the detection threshold of the fault voltage, it is determined that the matching control type direct-drive wind turbine set has a fault.

[0089] The effectiveness of matching control depends on two factors, namely the current working point and the depth of grid voltage drop, which determine whether the unloading circuit is activated. The logic of the fault signal F is as follows:

[0090]

[0091] In formula (1): U dc Refers to the DC voltage of the matching control type direct drive wind turbine, U dc,M Refers to the DC voltage detection threshold, U s Refers to the fault voltage of the matching control type direct drive wind turbine, U s,f Refers to the detection threshold of the fault voltage.

[0092] On the DC side, the action of the unloading circuit will adjust the state of the power balance equation. At this time, the voltage is constrained within the preset threshold and no longer directly responds to the fluctuation of the grid frequency. When the system enters the fault mode, the synchronization link is switched and the DC voltage synchronization link is cut off, so that it is phase locked during the fault period.

[0093] In some embodiments of the present application, see Figure 4The step 200 of determining the reactive power of the matching control type direct-drive wind turbine generator set in real time according to the voltage of the grid connection point of the matching control type direct-drive wind turbine generator set includes:

[0094] Step 201: determining in real time the nominal value of the reactive current corresponding to the reactive power according to the per unit value of the voltage at the grid connection point;

[0095] Step 202: Determine in real time the nominal value of the reactive power command of the reactive power during the fault period according to the nominal value of the d-axis component of the voltage at the grid connection point.

[0096] In order to meet the requirements of current limiting and voltage support, according to the indicators of the published "GC0137: Minimum Specifications for Providing UK Grid Capability" on grid control and the relevant requirements for low voltage ride-through of wind turbines in "GB / T19963.1-2021", the relationship between the grid connection point voltage and reactive current and the reactive power to be generated by the unit when the voltage drops is shown in equations (2) and (3):

[0097]

[0098] Where: i q Represents the nominal value of reactive current, I B Indicates the base value of the system output current, u s Indicates the per-unit value of the grid-connected point voltage, I max Indicates the normalized limit value of the inverter's short-circuit current amplitude, Q gref_lvrt Indicates the nominal value of the reactive power command under fault, U sd Indicates the grid connection point voltage U s The nominal value of the d-axis component of .

[0099] In this application, the rated capacity S is taken N =5MW is the power reference value S B , AC voltage rated value U N =563V is the voltage reference value U B , the system output current reference value I can be calculated B =5.9166kA. max =1.2pu as an example, when the grid voltage is less than 1p.u., the reactive current per unit value changes linearly according to a fixed slope, realizing the adaptive association between reactive current and grid voltage. At the same time, by combining equations (2) and (3), the reactive power command value of the unit will be adaptively associated with the grid voltage in the event of a fault, and reactive support can be achieved according to the designed curve.

[0100] Combining voltage feedforward switching and adaptive reactive power switching, adaptive reactive power switching control is given. Voltage feedforward control is introduced during the fault period, and the voltage feedforward instruction is changed to Usd , so that the amplitude generated by the converter changes synchronously with the amplitude generated by the power grid, achieving rapid matching of the internal potential with the fault voltage. In addition, phase locking is used during the fault period to achieve phase synchronization. The combination of the two satisfies the above steady-state AC component I tsb The conditions for obtaining the extreme value can limit the steady-state component of the fault current. At the same time, the steady-state operating point before and after the fault will not be changed, and the use of reactive power command switching can provide reactive support to the power grid.

[0101] In some embodiments of the present application, see Figure 5 , a transient adaptive control method for a matching control type direct-drive wind turbine generator set, further comprising:

[0102] Step 500: Generate the virtual resistor; further, see Figure 6 , step 500 comprises:

[0103] Step 501: Determine the virtual resistor according to the magnitude relationship between the output current of the grid-side inverter of the matching control type direct-drive wind turbine group and the threshold value of the starting current of the virtual resistor.

[0104] It is understandable that the adaptive reactive power switching control strategy only works on the steady-state component of the short-circuit current, and has little effect on suppressing the impact current at the moment of the fault. Given that the attenuation speed of the impact current is subject to certain factors, the attenuation process can be accelerated by introducing a virtual resistor, thereby achieving the effect of suppressing the impact current.

[0105] However, once the fixed value of the virtual resistance is set, it will not only reduce the attenuation time constant of the impact current, but will also inevitably affect the steady-state component of the short-circuit current and the transmission power of the entire system. Therefore, this paper designs an adaptive virtual resistance control strategy based on formula (4) so ​​that the virtual resistance value can be adjusted linearly with the change of current. This control has a suppressive effect on the transient component of the current and only acts at the moment of fault. The rest of the state is automatically adjusted back to the working point. While suppressing the impact current at the moment of fault, it can also eliminate the impact caused by the sudden change of the virtual resistance value.

[0106]

[0107] In formula (4): I t Represents the output current of the grid-side inverter of the matching control type direct-drive wind turbine; K v represents the virtual resistance adjustment coefficient; and I maxf The starting current threshold of the virtual resistor is defined.

[0108] From the above description, it can be seen that an embodiment of the present invention provides a transient adaptive control method for a matching-controlled direct-drive wind turbine group, including: first, when a matching-controlled direct-drive wind turbine group fails, the matching-controlled direct-drive wind turbine group is phase-locked by the unloading circuit of the matching-controlled direct-drive wind turbine group; then, when the matching-controlled direct-drive wind turbine group is in a fault period, the reactive power of the matching-controlled direct-drive wind turbine group is determined in real time according to the voltage of the grid-connected point of the matching-controlled direct-drive wind turbine group; and finally, the transient component of the current of the matching-controlled direct-drive wind turbine group is suppressed according to the pre-generated virtual resistance.

[0109] Based on the generation mechanism of transient current and the GC0137 reactive voltage support standard, the present invention proposes a transient adaptive control strategy for MC-PMSG that takes into account both current limiting and reactive voltage support. The main parts are as follows: The first part is to use fault detection and phase locking control to deal with the problem of loss of synchronization ability of the matching control grid during grid faults, and at the same time start the unloading circuit to maintain the stability of the power angle; the second part is adaptive reactive power switching control, which uses the influencing factors of transient current to control the internal potential to be equal to the grid voltage, meet the condition that the steady-state component of the fault current obtains a minimum value, and at the same time, reactive power design is performed according to the GC0137 standard to provide reactive support; the third part is adaptive virtual resistance control, which suppresses the transient component of the fault current at the moment of fault, accelerates the attenuation speed of the transient component, and shortens its duration.

[0110] To further illustrate the solution, the present invention also provides a specific implementation of a transient adaptive control method for a matching control type direct-drive wind turbine generator set, see Figure 7 as well as Figure 8 , the method includes the following contents:

[0111] S1: Obtain the current working point and the depth of the grid voltage drop to determine whether a low voltage fault occurs and whether to perform phase locking control;

[0112] Fig. 9 A control block diagram of the fault detection and generation method provided by the present invention, Fig.10 This is a control block diagram of the phase locking control provided by the present invention. Fig. 9 as well as Fig.10 The effectiveness of matching control depends on two factors, namely the current operating point and the depth of grid voltage drop, which determine whether the unloading circuit is activated. When the system enters the fault mode, the synchronization link is switched and the DC voltage synchronization link is cut off to make it phase locked during the fault period.

[0113] S2: Perform adaptive reactive power control according to the relevant requirements of reactive voltage support and current limiting.

[0114] Fig.11The adaptive reactive power switching control block diagram is shown in Figure 1. Combining voltage feedforward switching and adaptive reactive switching, the adaptive reactive power switching control is given. During the fault period, voltage feedforward control is introduced and the voltage feedforward instruction is changed to U sd , so that the amplitude generated by the converter changes synchronously with the amplitude generated by the power grid, achieving rapid matching of the internal potential with the fault voltage. In addition, phase locking is used during the fault period to achieve phase synchronization. The combination of the two satisfies the above steady-state AC component I tsb The conditions for obtaining the extreme value can limit the steady-state component of the fault current. At the same time, the steady-state operating point before and after the fault will not be changed, and the use of reactive power command switching can provide reactive support to the power grid.

[0115] S3: Perform adaptive virtual resistance control according to the current state at the moment of fault.

[0116] Feasibility verification: The engineering simulation example system model provided in this application is as follows Fig.12 As shown, four groups of control strategies are set as follows:

[0117] Strategy I is traditional control without any switching;

[0118] Strategy II adopts only adaptive reactive power switching control;

[0119] Strategy III is to use only adaptive virtual resistance control;

[0120] Strategy IV is the combination of adaptive reactive power switching control and adaptive virtual resistance control, that is, the MC-PMSG transient adaptive control strategy proposed in this invention. The simulation results of Strategy I, Strategy II, Strategy III and Strategy IV are shown in Figure 2. Fig.12 , Fig.13 , Fig.14 , Fig.15 , Fig.16 , Fig.17 , Fig.18 , Fig.19 , Fig. 20 , Fig.21 , Fig. 22 As shown, the effectiveness of the present invention is verified.

[0121] Figures 13 to 16 This is a comparison chart of the current limiting and reactive voltage support effects of different control strategies when the grid-connected point voltage drops to 0.2pu from 5s to 5.5s for the MC-PMSG model. Fig.13 are the waveforms of current, reactive power and synchronous frequency of strategy I, Fig.14 The waveforms of current, reactive power and synchronous frequency of strategy II are: Fig.15 The waveforms of current, reactive power and synchronous frequency of strategy III are: Fig.16The waveforms of current, reactive power and synchronous frequency of strategy IV.

[0122] like Figures 13 to 16 As shown in the figure, with strategy I, the current can only be maintained within 4 p.u. during the fault period, which is far beyond the tolerance of 1.2 to 1.5 times the rated current of the grid-forming converter. The synchronous frequency fluctuates significantly, and the dynamic reactive power provided will gradually decrease. When the fault is cleared, there will be a large fluctuation, and the current and reactive power cannot be restored to the original state in time. With strategies II, III, and IV, the steady-state component of the fault current is within 1.3 pu, the synchronous frequency is maintained at 1 p.u., and the reactive power can be stably increased to 0.2 pu. At the moment of the fault, there is a current shock in strategy II, and strategies III and IV can suppress the current shock. However, strategy III has a large harmonic component and a high distortion rate, and it is difficult to recover the reactive power after the fault is cleared. With strategy IV, the harmonic component is small, the distortion rate is low, the steady-state component and transient component of the fault current are limited to within 1.3 pu, and the reactive power recovers quickly after the fault is cleared.

[0123] In summary, the adoption of strategy IV, that is, the MC-PMSG transient adaptive control strategy proposed in the present invention, can achieve the suppression of the steady-state component and transient component of the fault current. Compared with the traditional control, the fault current can be controlled within 1.3pu and the waveform distortion rate of the current is the lowest, which meets the tolerance of the grid-forming converter of 1.2 to 1.5 times the rated current. At the same time, it can provide stable reactive voltage support during the fault, and the current and reactive power can quickly return to the state before the fault after the fault is cleared. Subsequent verifications are based on this control strategy.

[0124] In order to further verify the effectiveness of the MC-PMSG transient adaptive control strategy proposed in this invention under different grid strengths, the system short-circuit ratio is set to 4, 3, 2, and 1, corresponding to the scenario of changing from a strong grid to a weak grid. The fault is set to the grid voltage dropping to 0.2pu at 5s to 5.5s, and the corresponding waveform is as follows: Fig.17 as well as Fig.18 shown. Fig.17 as well as Fig.18 In the system for configuring the transient adaptive control strategy of MC-PMSG that takes into account both current limiting and reactive voltage support, the system short-circuit ratio is set to 4, 3, 2, and 1, corresponding to the scenario of changing from a strong power grid to a weak power grid. The fault is set to the corresponding waveform when the power grid voltage drops to 0.2pu at 5s to 5.5s. Among them, Fig.17 The left part is the current waveform when the short circuit ratio is 4. Fig.17 The right part is the current waveform when the short circuit ratio is 3. Fig.18 The left part is the current waveform when the short circuit ratio is 2. Fig.18 The right part is the current waveform when the short circuit ratio is 1.

[0125] Depend on Fig.17 as well as Fig.17 It can be seen that the control strategy described in this article does not exceed 1.3pu under the condition of grid voltage drop, which is applicable in scenarios with different grid strengths and meets the grid-building converter's tolerance of 1.2 to 1.5 times the rated current.

[0126] In order to verify the multi-condition applicability of the MC-PMSG transient adaptive control strategy proposed in the present invention, continuous high and low voltage ride-through and asymmetric faults at the grid connection point are set up, and the control strategy proposed in the present invention is compared with the traditional control to verify its effectiveness.

[0127] In order to verify the effectiveness of the MC-PMSG transient adaptive control strategy proposed in this invention under the continuous grid-connected point voltage ride-through, two groups of working conditions are designed: 1) the grid-connected point voltage drops to 0.2pu from 5s to 5.625s, rises to 1.3pu from 5.625s to 6.125s, and recovers to 1p.u. after 6.125s; 2) the grid-connected point voltage rises to 1.3pu from 5s to 5.5s, drops to 0.2pu from 5.5s to 6.125s, and recovers to 1p.u. after 6.125s. Comparing the traditional strategy and the MC-PMSG transient adaptive control strategy, as shown in Figure 2, the grid-connected point voltage drops to 0.2pu from 5s to 5.5s, and recovers to 1p.u. after 6.125s. Figures 19 to 21 As shown (the corresponding waveform of the MC-PMSG system's grid-connected point voltage continuously crossing high and low at 5s to 6.125s).

[0128] like Figures 19 to 21 As shown, under the condition of continuous voltage crossing at the grid connection point, the fault current will exceed 1.3pu and the recovery time will be long after the fault is cleared if the traditional control strategy is adopted. The MC-PMSG transient adaptive control strategy proposed in the present invention can ensure that the fault current does not exceed 1.3pu under the condition of different degrees of voltage drop at the grid connection point and can quickly recover to the original state after the fault is cleared, meeting the grid-connected converter's 1.2 to 1.5 times rated current tolerance.

[0129] In order to further verify the applicability of the MC-PMSG transient adaptive control strategy proposed in this invention to multiple working conditions, two faults, single-phase short circuit and two-phase ground short circuit, were respectively carried out at 5s to 5.5s. Fig. 22 (Corresponding waveform of single-phase short circuit of MC-PMSG system at 5s to 5.5s) and Fig.23 (The corresponding waveform of the two-phase ground short circuit in the MC-PMSG system at 5s to 5.5s) is shown.

[0130] like Fig. 22As shown in the figure (the left part is the grid connection point voltage waveform and current waveform of the traditional control strategy, and the right part is the grid connection point voltage waveform and current waveform of the transient adaptive control strategy of MC-PMSG that takes into account current limiting and reactive voltage support). Under the condition of single-phase ground short circuit fault, the fault current of traditional control will far exceed 1.3pu, the reactive voltage support will be unstable during the fault, and the grid connection point voltage will gradually decrease. However, the MC-PMSG transient adaptive control strategy proposed in this paper can keep the fault current no more than 1.3pu, meet the tolerance requirement of 1.2 to 1.5 times the rated current of the grid-connected converter, and provide stable reactive voltage support to 0.75pu. After the fault is cleared, the current and voltage can quickly return to their original state.

[0131] like Fig.23 As shown in the figure (the left part is the grid connection point voltage waveform and current waveform of the traditional control strategy, and the right part is the grid connection point voltage waveform and current waveform of the transient adaptive control strategy of MC-PMSG that takes into account both current limiting and reactive voltage support), under the condition of two-phase ground short circuit fault, the fault current of the traditional control will far exceed 1.3pu, the reactive voltage support will be unstable during the fault, and the grid connection point voltage will gradually decrease. However, the MC-PMSG transient adaptive control strategy proposed in this paper can keep the fault current no more than 1.3pu, meet the tolerance of 1.2 to 1.5 times the rated current of the grid-connected converter, and provide stable reactive voltage support to 0.5pu. After the fault is cleared, the current and voltage can quickly return to their original state.

[0132] In summary, the MC-PMSG transient adaptive control strategy that takes into account both current limiting and active reactive voltage support described in the present invention comprehensively considers factors such as short-circuit current, reactive voltage support and voltage source characteristics, and based on the generation mechanism of transient overcurrent and reactive voltage support standards, proposes a MC-PMSG transient adaptive control strategy that takes into account both current limiting and active reactive voltage support, which suppresses the steady-state component and transient component of current, provides stable reactive voltage support and retains the voltage source characteristics.

[0133] Under different grid strengths, the fault overcurrent of MC-PMSG can be effectively suppressed while providing stable reactive voltage support, meeting the grid-building converter's tolerance of 1.2 to 1.5 times the rated current. The parameter design is simple and reduces the device current limiting cost, which has certain engineering guidance significance.

[0134] From the above description, it can be seen that a specific application example of the present invention provides a transient adaptive control method for a matching-controlled direct-drive wind turbine group, including: first, when a matching-controlled direct-drive wind turbine group fails, the matching-controlled direct-drive wind turbine group is phase-locked by the unloading circuit of the matching-controlled direct-drive wind turbine group; then, when the matching-controlled direct-drive wind turbine group is in a fault period, the reactive power of the matching-controlled direct-drive wind turbine group is determined in real time according to the voltage of the grid-connected point of the matching-controlled direct-drive wind turbine group; and finally, the transient component of the current of the matching-controlled direct-drive wind turbine group is suppressed according to the pre-generated virtual resistance.

[0135] In summary, the present invention comprehensively considers factors such as the short-circuit current steady-state component, transient component, reactive voltage support, and voltage source characteristics, making up for the deficiency of the existing method of suppressing transient impact current without considering voltage support, retaining the MC-PMSG voltage source characteristics, and avoiding the problem of the control strategy being too dependent on system parameters due to the use of voltage vector limiting. The proposed control strategy can effectively suppress the fault overcurrent of MC-PMSG under different grid strengths while providing stable reactive voltage support, meeting the tolerance capacity of the grid-forming converter of 1.2 to 1.5 times the rated current, with simple parameter design and reduced device current limiting cost, and has certain engineering guidance significance.

[0136] Based on the same inventive concept, the embodiment of the present application also provides a transient adaptive control device for a matching control type direct-drive wind turbine group, which can be used to implement the method described in the above embodiment, such as the following embodiment. Since the principle of solving the problem by the transient adaptive control device for a matching control type direct-drive wind turbine group is similar to the transient adaptive control method for a matching control type direct-drive wind turbine group, the implementation of the transient adaptive control device for a matching control type direct-drive wind turbine group can refer to the implementation of the transient adaptive control method for a matching control type direct-drive wind turbine group, and the repeated parts will not be repeated. As used below, the term "unit" or "module" can be a combination of software and / or hardware that implements predetermined functions. Although the system described in the following embodiments is preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceived.

[0137] The embodiment of the present invention provides a specific implementation of a transient adaptive control device for a matching control type direct-drive wind turbine generator set that can implement a transient adaptive control method for a matching control type direct-drive wind turbine generator set. Fig.24 A transient adaptive control device for a matching control type direct-drive wind turbine generator system specifically includes the following contents:

[0138] The unit phase locking module 10 is used to phase lock the matching control type direct-drive wind turbine unit through the unloading circuit of the matching control type direct-drive wind turbine unit when the matching control type direct-drive wind turbine unit fails;

[0139] A reactive power real-time updating module 20, for determining the reactive power of the matched control type direct-drive wind turbine set in real time according to the voltage of the grid connection point of the matched control type direct-drive wind turbine set when the matched control type direct-drive wind turbine set is in a fault period; and

[0140] The current transient suppression module 30 is used to suppress the current transient component of the matching control type direct-drive wind turbine generator set according to the pre-generated virtual resistance.

[0141] In some embodiments of the present application, see Fig.25 , the unit phase locking module 10 comprises:

[0142] The synchronization link removal unit 10a is used to remove the DC voltage synchronization link of the matching control type direct-drive wind turbine generator set through the unloading circuit.

[0143] In some embodiments of the present application, see Fig.26 , a transient adaptive control device for a matching control type direct-drive wind turbine generator set, further comprising:

[0144] The unit fault judgment module 40 is used to judge that the matching control type direct-drive wind turbine unit has a fault when the DC voltage of the matching control type direct-drive wind turbine unit is greater than the detection threshold of the DC voltage and the fault voltage of the matching control type direct-drive wind turbine unit is less than the detection threshold of the fault voltage.

[0145] In some embodiments of the present application, see Fig. 27 , the reactive power real-time update module 20 comprises:

[0146] A reactive current nominal value determination unit 20a, configured to determine in real time the nominal value of the reactive current corresponding to the reactive power according to the per unit value of the voltage at the grid connection point;

[0147] The command nominal value determination unit 20b is used to determine the nominal value of the reactive power command during the fault period in real time according to the nominal value of the d-axis component of the voltage at the grid connection point.

[0148] In some embodiments of the present application, see Fig.28 , a transient adaptive control device for a matching control type direct-drive wind turbine generator set, further comprising:

[0149] The virtual resistance generating module 50 is used to generate the virtual resistance. Fig.29 , the virtual resistance generating module 50 comprises:

[0150] The virtual resistance generating unit 50a is used to determine the virtual resistance according to the magnitude relationship between the output current of the grid-side inverter of the matching control type direct-drive wind turbine group and the threshold value of the starting current of the virtual resistance.

[0151] From the above description, it can be seen that an embodiment of the present invention provides a transient adaptive control device for a matching-controlled direct-drive wind turbine group, including: a unit phase locking module, which is used to phase-lock the matching-controlled direct-drive wind turbine group through the unloading circuit of the matching-controlled direct-drive wind turbine group when a fault occurs in the matching-controlled direct-drive wind turbine group; a reactive power real-time update module, which is used to determine the reactive power of the matching-controlled direct-drive wind turbine group in real time according to the voltage of the grid-connected point of the matching-controlled direct-drive wind turbine group when the matching-controlled direct-drive wind turbine group is in a fault period; and a current transient suppression module, which is used to suppress the current transient component of the matching-controlled direct-drive wind turbine group according to a pre-generated virtual resistance.

[0152] The present invention comprehensively considers factors such as the short-circuit current steady-state component, transient component, reactive voltage support, and voltage source characteristics, making up for the deficiency of the existing method of suppressing transient impact current without considering voltage support, retaining the MC-PMSG voltage source characteristics, and avoiding the problem of the control strategy being too dependent on system parameters due to the use of voltage vector limiting. At the same time, the parameter design is simple and convenient for engineering practice.

[0153] The embodiment of the present application also provides a specific implementation of an electronic device capable of implementing all steps in the transient adaptive control method of the matching control type direct-drive wind turbine generator set in the above embodiment, see Fig.30 , electronic equipment specifically includes the following:

[0154] Processor (processor) 1201, memory (memory) 1202, communication interface (CommunicationsInterface) 1203 and bus 1204;

[0155] The processor 1201, the memory 1202, and the communication interface 1203 communicate with each other through the bus 1204; the communication interface 1203 is used to realize information transmission between the server device and the client device and other related devices;

[0156] The processor 1201 is used to call the computer program in the memory 1202. When the processor executes the computer program, all steps in the transient adaptive control method of the matching control type direct-drive wind turbine in the above embodiment are implemented. For example, when the processor executes the computer program, the following steps are implemented:

[0157] Step 100: When the matching control type direct-drive wind turbine set fails, the matching control type direct-drive wind turbine set is phase-locked through the unloading circuit of the matching control type direct-drive wind turbine set;

[0158] Step 200: when the matching control type direct-drive wind turbine set is in a fault period, determining the reactive power of the matching control type direct-drive wind turbine set in real time according to the voltage of the grid connection point of the matching control type direct-drive wind turbine set; and

[0159] Step 300: suppressing the current transient component of the matching control type direct-drive wind turbine generator system according to the pre-generated virtual resistance.

[0160] The embodiments of the present application also provide a computer-readable storage medium capable of implementing all the steps in the transient adaptive control method of the matching control type direct-drive wind turbine generator set in the above embodiment. The computer-readable storage medium stores a computer program. When the computer program is executed by a processor, all the steps of the transient adaptive control method of the matching control type direct-drive wind turbine generator set in the above embodiment are implemented. For example, when the processor executes the computer program, the following steps are implemented:

[0161] Step 100: When the matching control type direct-drive wind turbine set fails, the matching control type direct-drive wind turbine set is phase-locked through the unloading circuit of the matching control type direct-drive wind turbine set;

[0162] Step 200: when the matching control type direct-drive wind turbine set is in a fault period, determining the reactive power of the matching control type direct-drive wind turbine set in real time according to the voltage of the grid connection point of the matching control type direct-drive wind turbine set; and

[0163] Step 300: suppressing the current transient component of the matching control type direct-drive wind turbine generator system according to the pre-generated virtual resistance.

[0164] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the hardware + program embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0165] The above is a description of a specific embodiment of the specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0166] Although the present application provides method operation steps such as embodiments or flow charts, more or fewer operation steps may be included based on conventional or non-creative labor. The order of steps listed in the embodiments is only one way of executing the order of many steps and does not represent the only execution order. When the actual device or client product is executed, it can be executed in the order of the method shown in the embodiments or the drawings or in parallel (for example, in a parallel processor or multi-threaded processing environment).

[0167] For the convenience of description, the above devices are described in various modules according to their functions. Of course, when implementing the embodiments of this specification, the functions of each module can be implemented in the same or more software and / or hardware, or the module implementing the same function can be implemented by a combination of multiple sub-modules or sub-units. The device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0168] Those skilled in the art also know that, in addition to implementing the controller in a purely computer-readable program code, the controller can be made to implement the same function in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers by logically programming the method steps. Therefore, such a controller can be considered as a hardware component, and the devices for implementing various functions included therein can also be considered as structures within the hardware component. Or even, the devices for implementing various functions can be considered as both software modules for implementing the method and structures within the hardware component.

[0169] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0170] The memory may include non-permanent storage in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0171] The present specification embodiments may be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform specific tasks or implement specific abstract data types. The present specification embodiments may also be practiced in distributed computing environments where tasks are performed by remote processing devices connected through a communication network. In a distributed computing environment, program modules may be located in local and remote computer storage media, including storage devices.

[0172] Each embodiment in this specification is described in a progressive manner, and the same and similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment. In the description of this specification, the description of the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" 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 embodiment of this specification. In this specification, the schematic representation of the above terms does not necessarily target the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, in the absence of contradiction, a person skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0173] The above is only an example of the embodiment of the present specification and is not intended to limit the embodiment of the present specification. For those skilled in the art, the embodiment of the present specification may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the embodiment of the present specification shall be included in the scope of the claims of the embodiment of the present specification.

Claims

1. A transient adaptive control method for a matching control type direct-drive wind turbine generator system, characterized in that: include: When the matching control type direct-drive wind turbine set fails, the matching control type direct-drive wind turbine set is phase-locked through the unloading circuit of the matching control type direct-drive wind turbine set; When the matching control type direct-drive wind turbine set is in a fault period, the reactive power of the matching control type direct-drive wind turbine set is determined in real time according to the voltage of the grid connection point of the matching control type direct-drive wind turbine set; as well as The current transient component of the matching control type direct-drive wind turbine generator set is suppressed according to the pre-generated virtual resistance.

2. The transient adaptive control method according to claim 1, characterized in that: Phase locking is performed on the matching control type direct-drive wind turbine generator set, including: The DC voltage synchronization link of the matching control type direct-drive wind turbine generator set is cut off through the unloading circuit.

3. The transient adaptive control method according to claim 1, characterized in that: Also includes: When the DC voltage of the matching control type direct-drive wind turbine set is greater than the detection threshold of the DC voltage, and the fault voltage of the matching control type direct-drive wind turbine set is less than the detection threshold of the fault voltage, it is determined that the matching control type direct-drive wind turbine set has a fault.

4. The transient adaptive control method according to claim 1, characterized in that: Determining the reactive power of the matching control type direct-drive wind turbine generator set in real time according to the voltage of the grid connection point of the matching control type direct-drive wind turbine generator set includes: Determining in real time the nominal value of the reactive current corresponding to the reactive power according to the per-unit value of the voltage at the grid connection point; The nominal value of the reactive power instruction during the fault period is determined in real time according to the nominal value of the d-axis component of the voltage at the grid connection point.

5. The transient adaptive control method according to any one of claims 1 to 4, characterized in that: The steps of generating the virtual resistance include: The virtual resistor is determined according to a magnitude relationship between an output current of a grid-side inverter of the matching control type direct-drive wind turbine group and a threshold value of a starting current of the virtual resistor.

6. A transient adaptive control device for a matching control type direct-drive wind turbine generator set, characterized in that: include: A unit phase locking module, used for performing phase locking on the matching control type direct-drive wind turbine unit through the unloading circuit of the matching control type direct-drive wind turbine unit when a fault occurs to the matching control type direct-drive wind turbine unit; A reactive power real-time update module, used for determining the reactive power of the matching control type direct-drive wind turbine set in real time according to the voltage of the grid connection point of the matching control type direct-drive wind turbine set when the matching control type direct-drive wind turbine set is in a fault period; as well as The current transient suppression module is used to suppress the current transient component of the matching control type direct-drive wind turbine group according to the pre-generated virtual resistance.

7. The transient adaptive control device according to claim 6, characterized in that: The unit phase locking module comprises: The synchronization link cutting unit is used to cut off the DC voltage synchronization link of the matching control type direct-drive wind turbine set through the unloading circuit.

8. The transient adaptive control device according to claim 6, characterized in that: Also includes: The unit fault judgment module is used to judge that the matching control type direct-drive wind turbine unit has a fault when the DC voltage of the matching control type direct-drive wind turbine unit is greater than the detection threshold of the DC voltage and the fault voltage of the matching control type direct-drive wind turbine unit is less than the detection threshold of the fault voltage.

9. The transient adaptive control device according to claim 6, characterized in that: The reactive power real-time update module comprises: A reactive current nominal value determination unit, used to determine the nominal value of the reactive current corresponding to the reactive power in real time according to the per unit value of the voltage at the grid connection point; The command nominal value determination unit is used to determine the nominal value of the reactive power command of the reactive power during the fault period in real time according to the nominal value of the d-axis component of the voltage of the grid connection point.

10. The transient adaptive control device according to any one of claims 6 to 9, characterized in that: Also includes: A virtual resistance generating module, used to generate the virtual resistance, the virtual resistance generating module comprising: The virtual resistance generating unit is used to determine the virtual resistance according to the magnitude relationship between the output current of the grid-side inverter of the matching control type direct-drive wind turbine group and the threshold value of the starting current of the virtual resistance.

11. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instruction is executed by a processor, the steps of the transient adaptive control method of a matching control type direct-drive wind turbine generator set are implemented.

12. 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 steps of the transient adaptive control method of the matching control type direct-drive wind turbine set according to any one of claims 1 to 5 are implemented.

13. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the transient adaptive control method of a matching control type direct-drive wind turbine generator set are implemented.

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