An off-grid wind energy storage and load system applying MMC-HVDC and a commissioning method

Abstract

The present invention belongs to the technical field of wind power generation and energy storage, and discloses an off-grid wind energy storage and load system applying MMC-HVDC and a commissioning method. The system includes a wind turbine generator, a high-voltage bus, a voltage-source energy storage system, an active load P1, and an MMC-HVDC system. The output end of the wind turbine generator is divided into two paths. One path is connected to the low-voltage side of a box-type transformer T1 through a circuit breaker K1, and the other path is connected to the low-voltage side of the box-type transformer T1 through an inverter. The high-voltage side of the box-type transformer T1 is connected to one end of a circuit breaker K2 through the MMC-HVDC system, and the other end of the circuit breaker K2 is connected to the high-voltage bus. The output end of the voltage-source energy storage system is connected to the low-voltage side of a box-type transformer T2, and the high-voltage side of the box-type transformer T2 is connected to the high-voltage bus. The active load P1 is connected to the high-voltage bus. The present invention is of great significance for making full use of wind energy and alleviating the tension of power supply.

Description

Technical Field

[0001] The present invention belongs to the technical field of wind power generation and energy storage, and particularly relates to an off-grid wind energy storage and load system applying MMC-HVDC and a commissioning method therefor. Background Art

[0002] In recent years, with the increasingly prominent global energy shortage and environmental problems caused by traditional power generation, wind power generation has developed rapidly due to its mature technology and commercialization potential. However, wind power generation has volatility and randomness. The fluctuation of the wind speed will cause corresponding fluctuations in the output power of the wind turbine generator set. Therefore, wind power generation cannot provide continuous and stable power, and the power generation stability is poor, which leads to a series of problems such as fluctuations in wind power, output voltage, and frequency, and even threatens the stable and safe operation of the system. The energy storage system has flexible control and fast response, can suppress the fluctuation of wind power, and effectively support the voltage and frequency of the system. Therefore, a reasonable configuration of energy storage can improve the stability of the system.

[0003] At present, most of the research on the wind energy storage system is grid-connected. However, in actual engineering, the wind energy storage system needs to be commissioned in the off-grid mode before grid connection. If an AC cable is used during this process, the system voltage offset will occur, affecting the normal operation of the system. Summary of the Invention

[0004] The purpose of the present invention is to provide an off-grid wind energy storage and load system applying MMC-HVDC and a commissioning method therefor, so as to solve the technical problem of system voltage offset caused by using an AC cable during off-grid mode operation commissioning.

[0005] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0006] In a first aspect, the present invention provides an off-grid wind energy storage and load system applying MMC-HVDC, including:

[0007] A wind turbine generator, a high-voltage bus, a voltage-source energy storage system, an active load P1, and an MMC-HVDC system;

[0008] The output end of the wind turbine generator is divided into two paths. One path is connected to the low-voltage side of the box-type transformer T1 through the circuit breaker K1, and the other path is connected to the low-voltage side of the box-type transformer T1 through a converter; the high-voltage side of the box-type transformer T1 is connected to one end of the circuit breaker K2 through the MMC-HVDC system, and the other end of the circuit breaker K2 is connected to the high-voltage bus;

[0009] The output end of the voltage-source energy storage system is connected to the low-voltage side of the box-type transformer T2, and the high-voltage side of the box-type transformer T2 is connected to the high-voltage bus;

[0010] The active load P1 is connected to the high-voltage bus.

[0011] A further improvement of the present invention is that it further includes a current-limiting resistor; the other end of the circuit breaker K2 is connected to the high-voltage bus through the current-limiting resistor; a circuit breaker K3 is connected in parallel to the current-limiting resistor.

[0012] A further improvement of the present invention is that the voltage-source energy storage system is formed by paralleling m voltage-source energy storage devices; m is a positive integer greater than or equal to 1; the voltage-source energy storage system adopts virtual synchronous control.

[0013] A further improvement of the present invention is that the MMC-HVDC system includes a wind turbine side MMC, an energy storage side MMC, a wind turbine side MMC capacitor and an energy storage side MMC capacitor; the high-voltage side of the box-type transformer T1 is connected to the input end of the wind turbine side MMC, and the output end of the wind turbine side MMC is connected to the wind turbine side MMC capacitor; the energy storage side MMC capacitor is connected to the input end of the energy storage side MMC, and the output end of the energy storage side MMC is connected to one end of the circuit breaker K2; the positive poles of the wind turbine side MMC capacitor and the energy storage side MMC capacitor are connected by a first DC cable, and the negative poles of the wind turbine side MMC capacitor and the energy storage side MMC capacitor are connected by a second DC cable.

[0014] A further improvement of the present invention is that the wind turbine generator is a doubly-fed asynchronous wind turbine generator.

[0015] In a second aspect, the present invention provides a debugging method for an off-grid wind energy storage and load system applying MMC-HVDC, including the following steps:

[0016] Disconnect the circuit breaker K1, the circuit breaker K2 and the circuit breaker K3, connect the current-limiting resistor, start the voltage-source energy storage system, and input the active load for black start. Composed of the voltage-source energy storage system and the active load for black start To form an off-grid energy storage and load system;

[0017] When the off-grid energy storage and load system outputs stable voltage and frequency, close the circuit breaker K2 to complete the connection of the wind turbine side;

[0018] Set the control mode of the MMC-HVDC system: the energy storage side MMC adopts the rectification mode, and the wind turbine side MMC adopts the second inversion mode;

[0019] The MMC-HVDC system enters the uncontrolled start-up stage;

[0020] The MMC-HVDC system enters the controllable start-up stage;

[0021] Set the reference AC voltage of the constant DC voltage control of the wind turbine side MMC to rise at a set slope until the output is stable;

[0022] The stator voltage of the wind turbine starts to synchronize with the external voltage of the wind turbine. When the amplitudes, phases, and frequencies of the stator voltage and the external voltage of the wind turbine are the same, the grid connection condition is reached. The grid connection breaker K1 is closed, and the remaining active load is put into operation to form an off-grid wind energy storage load system.

[0023] A further improvement of the present invention lies in that: the active load for black start is less than 20% of the total capacity of the voltage source type energy storage system.

[0024] A further improvement of the present invention lies in that: in the steps of the uncontrolled start-up stage of the MMC-HVDC system, it specifically includes:

[0025] The MMC on the energy storage side takes energy from the AC high-voltage bus to charge the capacitors of the MMC on the wind turbine side and the MMC on the energy storage side. When the maximum value of the voltage at both ends of the DC side reaches the amplitude of the AC side line voltage, the uncontrolled start-up stage ends.

[0026] A further improvement of the present invention lies in that: the steps of the controllable start-up stage of the MMC-HVDC system specifically include:

[0027] After the end of the uncontrolled start-up stage, the circuit breaker K3 is closed to short-circuit the current-limiting resistor. The MMC on the energy storage side continues to charge the capacitors of the MMC on the wind turbine side and the MMC on the energy storage side in the rectification mode, and finally the voltages of the capacitors of the MMC on the wind turbine side and the MMC on the energy storage side reach the rated value U dc ; when a stable DC voltage is established on the energy storage side MMC, the MMC on the wind turbine side adopts the second inversion mode; the phase of the low-voltage side of the box-type transformer T2 is measured as the reference phase of the MMC on the wind turbine side.

[0028] A further improvement of the present invention lies in that: after the step of forming the off-grid wind energy storage load system, it further includes:

[0029] The control mode of the MMC-HVDC system is switched: the MMC on the wind turbine side adopts the rectification mode, the MMC on the energy storage side adopts the first inversion mode, the power of the wind turbine climbs to the rated power according to the set slope, the system is stable, and the output power of the wind turbine side is controlled by controlling the active power P ref and the reactive power Q ref of the MMC on the energy storage side.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The present invention provides an off-grid wind energy storage and load system applying MMC-HVDC. An MMC-HVDC system is adopted between the wind turbine and the high-voltage bus. First, the energy storage system is started, then the MMC-HVDC and the doubly-fed induction generator (DFIG) are started, and finally the control mode of the MMC-HVDC is switched to form a stable off-grid wind energy storage and load system for commissioning. Through the off-grid wind energy storage and load system applying MMC-HVDC proposed by the present invention, commissioning experiments can be carried out before the wind energy storage system is connected to the grid, which is of great significance for making full use of wind energy and alleviating the tension of power supply.

[0032] The present invention proposes a commissioning method for an off-grid wind energy storage and load system applying MMC-HVDC. First, the voltage-source energy storage is black-started to establish stable voltage and frequency, provide the system with self-starting ability, and respond to the power fluctuations on the wind turbine side and the load. Secondly, the MMC-HVDC is started. This process is a complex transient process. The main goal of the start-up control is to rapidly increase the DC-side voltage to the rated value through a series of auxiliary measures and certain control strategies, realize the pre-charging of the capacitors of each module, and at the same time, overcurrent and overvoltage should not be generated to avoid equipment damage. After the MMC-HVDC is started and a stable voltage is output to the wind turbine side, the DFIG is started to complete the dynamic networking. The control mode of the MMC is switched, the power of the DFIG starts to ramp up, the output power of the MMC on the energy storage side is controllable, and the off-grid wind energy storage and load system starts to operate stably. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The attached drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and the descriptions thereof are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0034] Figure 1 is a schematic structural diagram of an off-grid wind energy storage and load system applying MMC-HVDC;

[0035] Figure 2 is a schematic diagram of the voltages at both ends of the MMC of the dynamic networking device of the wind energy storage and load system;

[0036] Figure 3 is a schematic diagram of the influence of cable length on the system;

[0037] Figure 4 is a schematic diagram of constant DC voltage and constant reactive power control;

[0038] Figure 5 is a schematic diagram of constant DC voltage and constant reactive power control;

[0039] Figure 6 is a schematic diagram of constant AC voltage control. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0040] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments. It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments may be combined with each other.

[0041] The following detailed descriptions are all exemplary descriptions, aiming to provide further detailed explanations for the present invention. Unless otherwise specified, all technical terms adopted by the present invention have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention pertains. The terms used in the present invention are only for describing specific embodiments, and are not intended to limit the exemplary embodiments according to the present invention.

[0042] The voltage-source energy storage adopts traditional virtual synchronous control technology. When the wind energy storage system is debugged off-grid, due to the existence of an AC cable between the wind turbine and the high-voltage bus, the system voltage will deviate from the rated value during operation. If corresponding strategies are not adopted, the system may experience voltage over-limit. To solve this problem, the present invention adopts an MMC-HVDC system between the wind turbine and the high-voltage bus. First, the energy storage system is started, then the MMC-HVDC and the doubly-fed wind turbine are started, and finally the control mode of the MMC-HVDC is switched to form a stable off-grid wind energy storage load system for debugging.

[0043] Embodiment 1

[0044] Please refer to Figure 1 As shown, the present invention provides an off-grid wind energy storage load system applying MMC-HVDC, including: a wind turbine 100, a high-voltage bus 200, a voltage-source energy storage system 300, an MMC-HVDC system, a current-limiting resistor 700, and an active load P1. The voltage-source energy storage system 300 is composed of m voltage-source energy storage devices 301 connected in parallel; m is a positive integer greater than or equal to 1. The voltage-source energy storage system 300 adopts virtual synchronous control, which is divided into active frequency control and reactive voltage control, respectively simulating the speed regulation and excitation systems of a synchronous generator. The value-taking principle of the current-limiting resistor 700 is that neither the system current nor the arm current can exceed the current limit.

[0045] The output end of the wind turbine 100 is divided into two paths. One path is connected to the low-voltage side of a box-type transformer T1 through a circuit breaker K1, and the other path is connected to the low-voltage side of the box-type transformer T1 through a converter; the converter includes a machine-side converter 101 and a grid-side converter 102; the high-voltage side of the box-type transformer T1 is connected to one end of a circuit breaker K2 through the MMC-HVDC system, and the other end of the circuit breaker K2 is connected to the high-voltage bus 200 through a series-connected current-limiting resistor 700; a circuit breaker K3 is connected in parallel with the current-limiting resistor 700.

[0046] The output end of the voltage-source energy storage system 300 is connected to the low-voltage side of a box-type transformer T2, and the high-voltage side of the box-type transformer T2 is connected to the high-voltage bus 200.

[0047] The active load P1 is connected to the high-voltage bus 200.

[0048] In a specific embodiment, the wind turbine 100 is a doubly-fed induction wind turbine; the box-type transformer T1 is a 1140V / 35kV transformer; the box-type transformer T2 is a 380V / 35kV transformer; the MMC-HVDC system includes a wind turbine side MMC (Modular Multilevel Converter, abbreviated as MMC) 401, an energy storage side MMC 402, and a DC transmission line.

[0049] Figure 3 This is the influence of different cable lengths on the voltage at point A on the low-voltage side of the box-type transformer T2 before the wind turbine is connected. It can be seen that the longer the AC cable, the larger the capacitance, the more reactive power absorbed by the energy storage, and the higher the output voltage, which will affect the stable operation of the system.

[0050] Such as Figure 2 , U1 is the AC voltage of the wind turbine side MMC 401, and U2 is the AC voltage of the energy storage side MMC 402. At time t0, the output voltage of the energy storage is stable, and U2 reaches the rated value U ref . At time t1, the MMC-HVDC system starts up successfully. At this time, the wind turbine side MMC 401 is under constant AC voltage control, and the reference AC voltage rises at a certain slope. At time t2, the output AC voltage of the wind turbine side MMC 401 reaches the rated value U ref , and then step 7 can be carried out.

[0051] By adopting the above technical solution, through the control switching of the two MMCs on both sides of the MMC-HVDC, the off-grid system can be started up and operate stably.

[0052] Please refer to Figure 4 As shown, in the rectification mode, constant DC voltage and constant reactive power control are adopted to output stable DC power from the AC power; the detected DC voltage value V dc is compared with the DC voltage reference value V dcref , and its deviation is used as the inner-loop d-axis current reference command value i dref after PI regulation; the detected AC reactive power value Q and the reactive power reference value Q ref are converted into the q-axis current reference value i qref .

[0053] Please refer to Figure 5 As shown, in the first inversion mode, d-axis constant active power and q-axis constant reactive power control are adopted. The detected active power value P is compared with the active power reference value P ref , and its deviation is used as the inner-loop d-axis current reference command value i dref after PI regulation; the detected reactive power value Q and the reactive power reference value Q refFor comparison, its deviation is converted into the q-axis current reference value i after PI regulation as the inner loop. qref .

[0054] Please refer to Figure 6 As shown, for the second inverter mode, constant AC voltage control is adopted. U ref is the reference AC voltage. After decoupling and comparing with the measured AC voltage value, i dref and i qref are obtained. The required phase θ = 2πft of the MMC is used as the reference phase because the fan has not started yet. At this time, the fan side is a passive network and the reference phase of the fan side cannot be obtained through the PLL. The control of the MMC on the fan side is constant AC voltage control and a reference phase is required. The phase at point A is measured as the reference phase. Since the AC system voltage has not been established yet, the voltage outer loop is very likely to generate overshoot current and overshoot voltage, which will damage the converter valve. Slope control is adopted to make the reference voltage U ref rise to the rated value at a certain slope.

[0055] Embodiment 2

[0056] The present invention provides a debugging method for an off-grid wind energy storage and load system applying MMC-HVDC, including:

[0057] Step 1: Disconnect the circuit breakers K1, K2, and K3, connect the current-limiting resistor 700, start the voltage-source energy storage system 300, and input the active load for black start The voltage-source energy storage system 300 and the active load for black start constitute an off-grid energy storage and load system. The active load for black start is less than 20% of the total capacity of the voltage-source energy storage system 300;

[0058] Step 2: When the off-grid energy storage and load system outputs stable voltage and frequency, close the circuit breaker K2 to complete the connection of the fan side;

[0059] Step 3: Set the control mode of the MMC-HVDC system: The MMC on the energy storage side 402 adopts the rectification mode, and the MMC 401 on the fan side adopts the second inverter mode.

[0060] Step 4: After the fan side is connected, the MMC-HVDC system undergoes a two-stage startup process: In the uncontrolled startup stage, the MMC 402 on the energy storage side obtains energy from the AC high-voltage bus 200 to charge the capacitor 601 of the MMC on the fan side and the capacitor 602 of the MMC on the energy storage side. At this time, the trigger pulses of the MMC 401 on the fan side are in the locked state, and the uncontrolled rectifier circuit composed of the antiparallel diodes of the bridge arm realizes the charging of the capacitor 601 of the MMC on the fan side and the capacitor 602 of the MMC on the energy storage side. When the maximum value of the DC side voltage reaches the amplitude of the AC side line voltage, this stage ends.

[0061] Step 5: Enter the controllable startup phase. Close the circuit breaker K3 to short-circuit the current-limiting resistor 700. At this time, the energy storage side MMC402 operates in the rectification mode (constant DC voltage control) to continue charging the capacitor 601 of the wind turbine side MMC and the capacitor 602 of the energy storage side MMC until the voltages of the capacitor 601 of the wind turbine side MMC and the capacitor 602 of the energy storage side MMC reach the rated value U. dc . After the energy storage side MMC402 establishes a stable DC voltage, the wind turbine side MMC401 operates in the second inversion mode (constant AC voltage control). At this time, the wind turbine side MMC401 is equivalent to connecting to a passive network without an AC voltage source and cannot obtain the synchronous phase through the PLL. Measure the phase at point A on the energy storage side and set the reference phase of the wind turbine side to be the same as the phase of the energy storage side (since the wind turbine has not started yet, the wind turbine side is a passive network and cannot obtain the reference phase of the wind turbine side through the PLL. The control of the wind turbine side MMC is constant AC voltage control and requires a reference phase. Measure the phase at point A as the reference phase).

[0062] Step 6: Set the reference AC voltage of the constant DC voltage control of the wind turbine side MMC401 to rise at a set slope until the output is stable.

[0063] Step 7: The stator voltage of the wind turbine starts to synchronize with the external voltage of the wind turbine. When the amplitudes, phases, and frequencies of the stator voltage and the external voltage of the wind turbine are the same, the grid connection condition is reached. Close the grid connection circuit breaker K1. At this time, the startup of the wind turbine is completed, and the remaining active load is put into operation to form an off-grid wind energy storage load system.

[0064] Step 8: Switch the control mode of the MMC-HVDC system. The wind turbine side MMC401 operates in the rectification mode, and the energy storage side MMC402 operates in the first inversion mode. The power of the wind turbine ramps up to the rated power at a set slope, and the system is stable. At this time, by controlling the active power P ref and reactive power Q ref of the energy storage side MMC402, further control the output power of the wind turbine side. Considering the line losses of the DC cables 501 and 502 (with lengths of several kilometers or even dozens of kilometers) between the capacitor 601 of the wind turbine side MMC and the capacitor 602 of the energy storage side MMC, the output active power of the energy storage side MMC is less than the actual output of the doubly-fed wind turbine at this time (the wind turbine will output power, and the energy storage side MMC is equivalent to taking energy from the wind turbine and then outputting, so it will not exceed the active power of the wind turbine).

[0065] The present invention provides an off-grid wind energy storage and load system using MMC-HVDC and a commissioning method, which refers to a device for implementing differential dynamic networking control among a wind power generation system, an energy storage system, and an MMC-HVDC system under different operating conditions during off-grid operation. The off-grid system and the commissioning device can conduct experiments before the wind energy storage system is connected to the grid. This is of great significance for making full use of wind energy and alleviating the tight power supply situation.

[0066] As is known to those skilled in the art, the present invention can be implemented by other embodiments without departing from its spirit or essential characteristics. Therefore, the above-disclosed embodiments are illustrative in all aspects and not exclusive. All changes within the scope of the present invention or equivalent to the present invention are encompassed by the present invention.

Claims

1. A debugging method for an off-grid wind power storage and load system applying MMC-HVDC, characterized in that, The described off-grid wind energy storage and load system applying MMC-HVDC includes: a wind turbine (100), a high-voltage bus (200), a voltage-source energy storage system (300), an active load P1, and an MMC-HVDC system; the output end of the wind turbine (100) is divided into two paths, one path is connected to the low-voltage side of a box-type transformer T1 through a circuit breaker K1, and the other path is connected to the low-voltage side of the box-type transformer T1 through an inverter; the high-voltage side of the box-type transformer T1 is connected to one end of a circuit breaker K2 through the MMC-HVDC system, and the other end of the circuit breaker K2 is connected to the high-voltage bus (200); the output end of the voltage-source energy storage system (300) is connected to the low-voltage side of a box-type transformer T2, and the high-voltage side of the box-type transformer T2 is connected to the high-voltage bus (200); the active load P1 is connected to the high-voltage bus (200); it further includes a current-limiting resistor (700); the other end of the circuit breaker K2 is connected to the high-voltage bus (200) through the current-limiting resistor (700); a circuit breaker K3 is connected in parallel to the current-limiting resistor (700); the MMC-HVDC system includes a wind turbine side MMC (401), an energy storage side MMC (402), a wind turbine side MMC capacitor (601), and an energy storage side MMC capacitor (602); the high-voltage side of the box-type transformer T1 is connected to the input end of the wind turbine side MMC (401), and the output end of the wind turbine side MMC (401) is connected to the wind turbine side MMC capacitor (601); the energy storage side MMC capacitor (602) is connected to the input end of the energy storage side MMC (402), and the output end of the energy storage side MMC (402) is connected to one end of the circuit breaker K2; the positive poles of the wind turbine side MMC capacitor (601) and the energy storage side MMC capacitor (602) are connected through a first DC cable (501), and the negative poles of the wind turbine side MMC capacitor (601) and the energy storage side MMC capacitor (602) are connected through a second DC cable (502); The described commissioning method includes the following steps: Disconnect circuit breakers K1, K2 and K3, connect the current-limiting resistor (700), start the voltage-source energy storage system (300), and connect the active load for black start , and the voltage-source energy storage system (300) and the active load for black start constitute an off-grid energy storage and load system; After the off-grid energy storage and load system outputs stable voltage and frequency, close the circuit breaker K2 to complete the connection of the wind turbine side; Set the control mode of the MMC-HVDC system: the energy storage side MMC (402) adopts the rectification mode, and the wind turbine side MMC (401) adopts the second inversion mode; The MMC-HVDC system enters the uncontrolled startup stage; The MMC-HVDC system enters the controllable startup stage; Set the reference AC voltage of the constant DC voltage control of the wind turbine side MMC (401) to rise according to the set slope until the output is stable; The stator voltage of the wind turbine (100) starts to synchronize with the external voltage of the wind turbine. When the stator voltage is consistent with the external voltage of the wind turbine in amplitude, phase, and frequency, the grid connection condition is reached. Close the grid connection circuit breaker K1 and input the remaining active load to form an off-grid wind energy storage and load system.

2. The debugging method according to claim 1, wherein The active load for black start is less than 20% of the total capacity of the voltage source type energy storage system (300).

3. The debugging method according to claim 1, wherein In the steps of the MMC-HVDC system entering the uncontrolled startup stage, it specifically includes: The energy storage side MMC (402) draws energy from the AC high-voltage bus (200) to charge the capacitor of the wind turbine side MMC (601) and the capacitor of the energy storage side MMC (602). When the maximum value of the voltage at both ends of the DC side reaches the amplitude of the AC side line voltage, the uncontrolled startup stage ends.

4. The debugging method according to claim 1, characterized in that, The steps for the controllable startup stage of the MMC-HVDC system specifically include: At the end of the uncontrolled starting stage, the circuit breaker K3 is closed to short-circuit the current-limiting resistor (700). The MMC (402) on the energy storage side continues to charge the capacitor (601) of the MMC on the wind turbine side and the capacitor (602) of the MMC on the energy storage side in the rectification mode, and finally the voltages of the capacitor (601) of the MMC on the wind turbine side and the capacitor (602) of the MMC on the energy storage side reach the rated value U dc ; after the MMC (402) on the energy storage side has established a stable DC voltage, the MMC (401) on the wind turbine side adopts the second inversion mode; the phase of the low-voltage side of the box-type transformer T2 is measured as the reference phase of the MMC (401) on the wind turbine side.

5. The debugging method according to claim 1, wherein After the steps of forming the off-grid wind energy storage load system, it further includes: The control mode of the MMC-HVDC system is switched: the MMC on the wind turbine side (401) adopts the rectification mode, and the MMC on the energy storage side (402) adopts the first inversion mode. The power of the wind turbine (100) ramps up to the rated power at a set slope, and the system is stable. By controlling the active power P ref and the reactive power Q ref of the MMC on the energy storage side (402), the output power of the wind turbine side is controlled.

6. The debugging method according to claim 1, wherein The voltage source type energy storage system (300) is formed by paralleling m voltage source type energy storage devices (301); m is a positive integer greater than or equal to 1; the voltage source type energy storage system (300) adopts virtual synchronous control.

7. The debugging method according to claim 1, wherein The wind turbine (100) is a doubly-fed asynchronous wind turbine.

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