Gas turbine black start system and method based on high-voltage direct-coupled energy storage converter

Abstract

The application relates to the technical field of power electronic applications, and discloses a gas turbine black start system and method based on a high-voltage direct-hanging energy storage converter, which comprises a high-voltage direct-hanging energy storage converter, a static start frequency converter, an excitation system, a diesel generator, a gas turbine, a bus, circuit breakers QF1, QF2, QF3, QF4, an output reactor L1 and a grid-connected reactor L2, the high-voltage direct-hanging energy storage converter is composed of a high-voltage direct-hanging energy storage converter control system, a plurality of energy storage power units and the grid-connected reactor L2, and the static start frequency converter is composed of a split transformer, a rectification circuit, a direct-current circuit, an inversion circuit, the output reactor L1 and a static start frequency converter control system. The application solves the problem of start failure caused by unstable power supply of the static start frequency converter, and effectively reduces the influence of problems such as harmonic, voltage sag and power fluctuation of the power supply side of the static start frequency converter on the start process in the black start process of the gas turbine.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power electronics, in particular to a gas turbine black start system and method based on a high-voltage direct-hanging energy storage converter. BACKGROUND

[0002] Generally, gas turbine startup requires stable power grid power supply, but the gas turbine black start mode plays an important role in accelerating the recovery of the power system and reducing the impact in the case of a large-scale power failure or when the power grid cannot supply power.

[0003] The traditional gas turbine black start scheme mainly uses a diesel generator to supply power to a static start converter to drive the gas turbine. However, the wear, damage or aging of internal components of the diesel generator, such as the flywheel, camshaft and connecting rod, etc., the aging of the circuit, the aging of the capacitor, etc., will cause the output power of the diesel generator to be unstable or interrupted. In addition, too high content of impurities in the fuel, unstable oil quality, insufficient oil pump pressure, etc. will affect the combustion efficiency of the diesel generator, causing the active power to be unstable, and the output power of the diesel generator to decrease or produce intermittent output. Furthermore, the diesel generator has a small capacity, and the input side harmonics of the static start converter affect the stability of the output voltage of the diesel generator.

[0004] Using a diesel generator to assist in gas turbine black start, the unstable output of the diesel generator is easy to cause large fluctuations in the output of the static start converter or cause faults in the static start converter, thereby causing the gas turbine to fail to start.

[0005] In view of the problems in the related art, no effective solution has been proposed so far. SUMMARY

[0006] In view of the problems in the related art, the present application proposes a gas turbine black start system and method based on a high-voltage direct-hanging energy storage converter to overcome the above technical problems existing in the prior art.

[0007] To this end, the specific technical solutions adopted by the present application are as follows:

[0008] According to one aspect of the present application, a gas turbine black start system based on a high-voltage direct-hanging energy storage converter is provided, comprising a high-voltage direct-hanging energy storage converter, a static start converter, an excitation system, a diesel generator, a gas turbine, a bus, circuit breakers QF1, QF2, QF3, QF4, an output reactor L1 and a grid-connected reactor L2.

[0009] The bus is connected with the power grid and the diesel generator output through the circuit breaker QF1 and the circuit breaker QF2 respectively, the gas turbine is connected with the bus through the circuit breaker QF5, the static starting frequency converter and the circuit breaker QF4 in sequence, the high-voltage direct-hanging energy storage converter is connected with the bus through the circuit breaker QF3, the excitation system receives the excitation instruction of the static starting frequency converter control system, and the output end of the excitation system is connected with the gas turbine;

[0010] The high-voltage direct-hanging energy storage converter is composed of a high-voltage direct-hanging energy storage converter control system, a plurality of energy storage power units and a grid-connected reactor L2, and the high-voltage direct-hanging energy storage converter control system is in communication connection with each energy storage power unit, used for collecting state information, fault information, mode information and instruction information interaction, the energy storage power unit is used for storing / releasing electric energy, and the three-phase output of the high-voltage direct-hanging energy storage converter is connected with the power grid through the grid-connected reactor L2.

[0011] The static starting frequency converter is composed of a split transformer T, a rectifier circuit, a direct-current circuit, an inverter circuit, an output reactor L1 and a static starting frequency converter control system, the output end of the split transformer T is connected with the input end of the rectifier circuit, the output end of the rectifier circuit is connected to the inverter circuit through the direct-current circuit, and the output end of the inverter circuit is connected with the output reactor L1.

[0012] As preferred, the alternating current ports of the plurality of energy storage power units are connected in series with each other, the alternating current ports of the first stage not connected with other energy storage power units are connected with each other to form a neutral point, and the alternating current ports of the Nth stage not connected with other energy storage power units form a three-phase alternating current interface.

[0013] The direct-current side of the energy storage power unit is connected with a battery or other energy storage element, the high-voltage direct-hanging energy storage converter control system controls the energy storage power unit through an optical fiber communication mode, converts the direct-current electricity stored by the battery and the alternating current electricity into each other, and realizes the bidirectional flow of electric energy.

[0014] As preferred, the energy storage power unit transmits unit information to the high-voltage direct-hanging energy storage converter control system, so as to realize the real-time monitoring and protection of the energy storage power unit by the high-voltage direct-hanging energy storage converter control system.

[0015] As preferred, the rectifier circuit includes alternating current-direct current converters AC / DC1 and AC / DC2, the direct-current circuit includes a reactor L3, and the inverter circuit includes a direct current-alternating current converter DC / AC.

[0016] The split transformer T is connected with the AC side of the AC / DC converter 1 and the AC / DC converter 2 respectively, the DC side of the AC / DC converter 1 and the AC / DC converter 2 are connected in series and connected to the DC / AC converter through the reactor L3.

[0017] As preferred, the system further comprises a gas turbine control system, and the gas turbine control system sends voltage and current instructions to the high-voltage direct-coupled energy storage converter control system of the high-voltage direct-coupled energy storage converter and the static starting frequency converter control system of the static starting frequency converter.

[0018] As preferred, when the circuit breaker QF1 and the circuit breaker QF3 are closed, and the circuit breaker QF2 and the circuit breaker QF4 are open, the high-voltage direct-coupled energy storage converter is connected to the power grid, realizing battery charging in the energy storage power unit and ensuring that the state of charge of the battery in the energy storage power unit is normal before black start;

[0019] When the circuit breaker QF2 and the circuit breaker QF3 are closed, and the circuit breaker QF1 and the circuit breaker QF4 are open, the high-voltage direct-coupled energy storage converter is connected to the diesel generator, realizing battery charging in the energy storage power unit and ensuring that the state of charge of the battery in the energy storage power unit is normal before black start;

[0020] When the circuit breaker QF2, the circuit breaker QF3, the circuit breaker QF4 and the circuit breaker QF5 are closed, and the circuit breaker QF1 is open, the diesel generator, the high-voltage direct-coupled energy storage converter and the input side of the static starting frequency converter are connected, realizing gas turbine black start based on the high-voltage direct-coupled energy storage converter.

[0021] As preferred, the three-phase voltage signal and the current signal of the output side of the high-voltage direct-coupled energy storage converter and the input side current signal of the static starting frequency converter are connected to the sampling interface of the high-voltage direct-coupled energy storage converter through sensors.

[0022] According to another aspect of the present application, a gas turbine black start method based on a high-voltage direct-coupled energy storage converter is provided, which comprises the following steps:

[0023] S1, under the condition that the circuit breaker QF2, the circuit breaker QF3, the circuit breaker QF4 and the circuit breaker QF5 are closed, the diesel generator is started to work at a power frequency, so that the high-voltage direct-coupled energy storage converter completes pre-charging and is in a hot standby state;

[0024] S2, start the high-voltage direct-hanging energy storage converter and the static starting frequency converter, and start the gas turbine through the static starting frequency converter; the high-voltage direct-hanging energy storage converter is used to detect the three-phase voltage and current on the output side in real time, and the input side current of the static starting frequency converter is detected at the same time;

[0025] S3, the voltage angle is obtained through a phase-locked loop module, the input side voltage active component of the high-voltage direct-hanging energy storage converter and the input side current active component of the high-voltage direct-hanging energy storage converter are calculated according to the input side voltage and current of the high-voltage direct-hanging energy storage converter, and the input side current active component and the current reactive component of the static starting frequency converter are calculated according to the input side current of the static starting frequency converter;

[0026] S4, based on the voltage and current instructions of the gas turbine control system, the compensation active current instruction and the compensation reactive current instruction of the high-voltage direct-hanging energy storage converter are calculated; the three-phase output voltage instruction of the high-voltage direct-hanging energy storage converter is calculated based on coordinate transformation;

[0027] S5, the high-voltage direct-hanging energy storage converter sends the calculation results to the energy storage power unit, the energy storage power unit outputs pulses, and the input side reactive and active power compensation of the static starting frequency converter is realized.

[0028] As preferred, the high-voltage direct-hanging energy storage converter has the functions of providing short-time reactive and active power support and redundant design, and under the condition that a preset number of energy storage power units fail, the failed energy storage power unit can be bypassed to continue to complete the input side reactive and active power compensation function of the static starting frequency converter.

[0029] The gas turbine black start system and method based on the high-voltage direct-hanging energy storage converter have the advantages that the problems of starting failure caused by unstable power supply of the static starting frequency converter are solved, and the influence of the problems of harmonic, voltage sag, power fluctuation and the like on the power supply side of the static starting frequency converter on the starting process in the gas turbine black start process is effectively reduced. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0031] Figure 1 is a structural block diagram of a gas turbine black start system based on a high-voltage direct-hanging energy storage converter according to an embodiment of the present application;

[0032] Figure 2is a flow chart of a gas turbine black start method based on a high-voltage direct-hanging energy storage converter according to an embodiment of the present application. DETAILED DESCRIPTION

[0033] To further illustrate the embodiments, the present application provides drawings which are part of the disclosure of the present application, mainly used to illustrate the embodiments, and can be used to explain the operating principle of the embodiments in conjunction with the related description of the specification. Those skilled in the art should understand other possible implementations and advantages of the present application by referring to these contents. The components in the drawings are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0034] According to an embodiment of the present application, a gas turbine black start system and method based on a high-voltage direct-hanging energy storage converter are provided.

[0035] The present application will be further described in conjunction with the drawings and specific embodiments, as shown in Figure 1 According to an embodiment of the present application, a gas turbine black start system based on a high-voltage direct-hanging energy storage converter is provided, comprising a high-voltage direct-hanging energy storage converter, a static start frequency converter, an excitation system, a diesel generator, a gas turbine, a bus, a circuit breaker QF1, a circuit breaker QF2, a circuit breaker QF3, a circuit breaker QF4, an output reactor L1 and a grid-connected reactor L2.

[0036] The bus is connected to the power grid and the diesel generator through the circuit breaker QF1 and the circuit breaker QF2, respectively. The gas turbine is connected to the bus through the circuit breaker QF5, the static start frequency converter and the circuit breaker QF4 in turn. The high-voltage direct-hanging energy storage converter is connected to the bus through the circuit breaker QF3. The excitation system receives the excitation instruction of the static start frequency converter control system, and the output end of the excitation system is connected to the gas turbine.

[0037] The high-voltage direct-hanging energy storage converter is composed of a high-voltage direct-hanging energy storage converter control system, 3*N energy storage power units and a grid-connected reactor L2. The high-voltage direct-hanging energy storage converter control system is communicatively connected to each energy storage power unit for collecting state information, fault information, mode information and instruction information interaction. The energy storage power unit is used for storing / releasing electric energy. The three-phase output of the high-voltage direct-hanging energy storage converter is connected to the power grid through the grid-connected reactor L2.

[0038] The AC ports of a plurality of energy storage power units are connected in series with each other. The AC ports of the first stage not connected to other energy storage power units are connected to each other to form a neutral point. The AC ports of the Nth stage not connected to other energy storage power units form a three-phase AC interface.

[0039] The DC side of the energy storage power unit is connected to a battery or other energy storage element. The high-voltage direct-connected energy storage converter control system controls the energy storage power unit via fiber optic communication, converting the DC power stored in the battery into AC power, thus achieving bidirectional energy flow. The energy storage power unit transmits its information to the high-voltage direct-connected energy storage converter control system, enabling the system to monitor and protect the energy storage power unit in real time.

[0040] The static start frequency converter consists of a split transformer T, a rectifier circuit, a DC circuit, an inverter circuit, an output reactor L1, and a static start frequency converter control system. The output terminal of the split transformer T is connected to the input terminal of the rectifier circuit. The output terminal of the rectifier circuit is connected to the inverter circuit through the DC circuit. The output terminal of the inverter circuit is connected to the output reactor L1.

[0041] Specifically, the rectifier circuit includes AC-DC converters AC / DC1 and AC / DC2, the DC circuit includes reactor L3, and the inverter circuit includes a DC-AC converter DC / AC; wherein, the split transformer T is connected to the AC side of AC-DC converters AC / DC1 and AC-DC converters AC / DC2 respectively, and the DC sides of AC-DC converters AC / DC1 and AC-DC converters AC / DC2 are connected in series and connected to the DC-AC converter DC / AC through reactor L3.

[0042] Furthermore, this embodiment also includes a TCS gas turbine control system, which transmits voltage commands. Current command The data is sent to the high-voltage direct-connected energy storage converter control system of the high-voltage direct-connected energy storage converter and the static start frequency converter control system of the static start frequency converter.

[0043] In this embodiment, when circuit breakers QF1 and QF3 are closed and circuit breakers QF2 and QF4 are open, the high-voltage direct-connected energy storage converter can be connected to the power grid to charge the battery in the energy storage power unit and ensure that the battery in the energy storage power unit is in a normal state of charge before black start.

[0044] When circuit breakers QF2 and QF3 are closed and circuit breakers QF1 and QF4 are open, the high-voltage direct-connected energy storage converter can be connected to the diesel generator to charge the battery in the energy storage power unit and ensure that the battery in the energy storage power unit is in a normal state of charge before black start.

[0045] When circuit breakers QF2, QF3, QF4, and QF5 are closed and circuit breaker QF1 is open, the input sides of the diesel generator, the high-voltage direct-connected energy storage converter, and the static start frequency converter are connected together, and the gas turbine black start based on the high-voltage direct-connected energy storage converter is realized through the gas turbine black start method based on the high-voltage direct-connected energy storage converter.

[0046] In this embodiment, the three-phase voltage signal U on the output side of the high-voltage direct-connected energy storage converter PCS_abc Current signal I PCS_abc and the input current signal I of the static start inverter SFC_abc All are connected to the sampling interface of the high-voltage direct-connected energy storage converter via sensors.

[0047] According to another aspect of the invention, such as Figure 2 As shown, a black start method for gas turbines based on high-voltage direct-connected energy storage converters is provided. This black start method for gas turbines based on high-voltage direct-connected energy storage converters includes the following steps:

[0048] S1. With circuit breakers QF2, QF3, QF4 and QF5 closed, start the diesel generator to the power frequency so that the high-voltage direct-connected energy storage converter completes pre-charging and is in hot standby mode.

[0049] S2. Start the high-voltage direct-connected energy storage converter and the static starter frequency converter, and drive the gas turbine to start through the static starter frequency converter (i.e., the static starter frequency converter drives the gas turbine to start from the gas turbine turning speed); use the high-voltage direct-connected energy storage converter to detect the three-phase voltage and current on the output side in real time, and at the same time detect the input current of the static starter frequency converter.

[0050] S3. Obtain the voltage angle through the phase-locked loop module, calculate the active component of the voltage and the active component of the current on the input side of the high-voltage direct-connected energy storage converter based on the input voltage and current of the high-voltage direct-connected energy storage converter, and calculate the active component of the current and the reactive component of the current on the input side of the static start frequency converter based on the input current of the static start frequency converter.

[0051] The formula for calculating the active component of the input voltage of the high-voltage direct-connected energy storage converter is as follows:

[0052]

[0053] The formula for calculating the active component of the input current of a high-voltage direct-connected energy storage converter is as follows:

[0054]

[0055] The formulas for calculating the active and reactive components of the input current of a static start frequency converter are as follows:

[0056]

[0057] In the formula, U PCS_d U represents the active component of the input voltage of a high-voltage direct-connected energy storage converter; PCS_q U represents the reactive component of the input voltage of the high-voltage direct-connected energy storage converter; θ represents the voltage angle; PCS_a U represents the input phase A voltage of the high-voltage direct-connected energy storage converter; PCS_b U represents the input phase B voltage of the high-voltage direct-connected energy storage converter; PCS_c This represents the input-side C-phase voltage of the high-voltage direct-connected energy storage converter;

[0058] I PCS_d I represents the active component of the input current of a high-voltage direct-connected energy storage converter. PCS_q I represents the reactive component of the input current of a high-voltage direct-connected energy storage converter. PCS_a I represents the input phase A current of the high-voltage direct-connected energy storage converter. PCS_b I represents the input phase B current of the high-voltage direct-connected energy storage converter. PCS_c This represents the C-phase current on the input side of the high-voltage direct-connected energy storage converter;

[0059] S4. Based on the voltage and current commands of the gas turbine control system, calculate the compensation active current command and compensation reactive current command of the high-voltage direct-connected energy storage converter; calculate the three-phase output voltage command of the high-voltage direct-connected energy storage converter based on coordinate transformation.

[0060] The calculation formula for the active current compensation command of the high-voltage direct-connected energy storage converter is as follows:

[0061]

[0062] The formula for calculating the reactive current compensation command of a high-voltage direct-connected energy storage converter is as follows:

[0063]

[0064] In the formula, This indicates a command to compensate for active current in a high-voltage direct-connected energy storage converter. This indicates the current command for the gas turbine control system; This indicates a command to compensate for reactive current in a high-voltage direct-connected energy storage converter.

[0065] The formula for calculating the dq-axis voltage command of the high-voltage direct-connected energy storage converter is as follows:

[0066]

[0067] In the formula, This indicates the d-axis output voltage command for the high-voltage direct-connected energy storage converter. This indicates the q-axis output voltage command for the high-voltage direct-connected energy storage converter; K PCS_P K represents the closed-loop proportional parameter of the high-voltage direct-connected energy storage converter. PCS_I The parameters represent the closed-loop integral parameters of the high-voltage direct-connected energy storage converter; S represents the complex frequency variable; ω represents the angular velocity; and L2 represents the inductance value of the grid-connected reactor.

[0068] The formula for calculating the three-phase output voltage command of a high-voltage direct-connected energy storage converter is as follows:

[0069]

[0070] In the formula, This indicates the A-phase output voltage command for the high-voltage direct-connected energy storage converter; This indicates the B-phase output voltage command for the high-voltage direct-connected energy storage converter. This indicates the C-phase output voltage command for the high-voltage direct-connected energy storage converter.

[0071] S5, the high-voltage direct-connected energy storage converter sends the calculation results to the energy storage power unit, and each stage of the energy storage power unit outputs pulses to realize reactive and active power compensation on the input side of the static start frequency converter.

[0072] In this embodiment, during the black start process of the gas turbine, the output voltage of the diesel generator drops, and the high-voltage direct-connected energy storage converter (PCS) has the ability to provide reactive and active power support for a short time.

[0073] In this embodiment, both the black start process of the gas turbine under no grid power supply conditions and the start-up process of the gas turbine under abnormal grid power supply conditions are realized.

[0074] The high-voltage direct-connected energy storage converter (PCS) has a redundancy design function. Under the condition that a reasonable number of energy storage power units fail, it can bypass the faulty energy storage power units and continue to perform the reactive and active power compensation functions of the input side of the static start inverter (SFC).

[0075] In summary, by utilizing the above-mentioned technical solutions of the present invention, the gas turbine black start system and method based on high-voltage direct-connected energy storage converter proposed in this invention solves the problem of start-up failure caused by unstable power supply of static start inverter, and effectively reduces the impact of problems such as harmonics, voltage sags, and power fluctuations on the power supply side of the static start inverter on the start-up process during gas turbine black start.

[0076] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A gas turbine black start system based on a high-voltage direct-connected energy storage converter, characterized in that, The gas turbine black start system based on the high-voltage direct-connected energy storage converter includes a high-voltage direct-connected energy storage converter, a static start frequency converter, an excitation system, a diesel generator, a gas turbine, a bus, circuit breakers QF1, QF2, QF3, and QF4, an output reactor L1, and a grid-connected reactor L2. The busbar is connected to the power grid and the output of the diesel generator through circuit breaker QF1 and circuit breaker QF2 respectively. The gas turbine is connected to the busbar in sequence through circuit breaker QF5, the static start inverter and circuit breaker QF4. The high-voltage direct-connected energy storage converter is connected to the busbar through circuit breaker QF3. The excitation system receives the excitation command from the static start inverter control system. The output of the excitation system is connected to the gas turbine. The high-voltage direct-connected energy storage converter consists of a high-voltage direct-connected energy storage converter control system, several energy storage power units, and a grid-connected reactor L2. The high-voltage direct-connected energy storage converter control system is communicatively connected to each energy storage power unit for the exchange of status information, fault information, mode information, and command information. The energy storage power units are used to store / release electrical energy. The three-phase output of the high-voltage direct-connected energy storage converter is connected to the power grid through the grid-connected reactor L2. The static start frequency converter consists of a split transformer T, a rectifier circuit, a DC circuit, an inverter circuit, an output reactor L1, and a static start frequency converter control system. The output terminal of the split transformer T is connected to the input terminal of the rectifier circuit. The output terminal of the rectifier circuit is connected to the inverter circuit through the DC circuit. The output terminal of the inverter circuit is connected to the output reactor L1. When circuit breakers QF1 and QF3 are closed and circuit breakers QF2 and QF4 are open, the high-voltage direct-connected energy storage converter is connected to the power grid to charge the battery in the energy storage power unit and ensure that the battery in the energy storage power unit is in a normal state of charge before black start. When circuit breakers QF2 and QF3 are closed and circuit breakers QF1 and QF4 are open, the high-voltage direct-connected energy storage converter is connected to the diesel generator to charge the battery in the energy storage power unit and ensure that the battery in the energy storage power unit is in a normal state of charge before black start. When circuit breakers QF2, QF3, QF4, and QF5 are closed and circuit breaker QF1 is open, the diesel generator, the high-voltage direct-connected energy storage converter, and the static start inverter are connected at their input sides, enabling black start of the gas turbine based on the high-voltage direct-connected energy storage converter.

2. The gas turbine black start system based on a high-voltage direct-connected energy storage converter according to claim 1, characterized in that, The AC ports of several energy storage power units are connected in series. The AC ports of the first stage that are not connected to other energy storage power units are connected to each other to form a neutral point. The AC ports of the Nth stage that are not connected to other energy storage power units form a three-phase AC interface. The DC side of the energy storage power unit is connected to a battery or other energy storage element. The high-voltage direct-connected energy storage converter control system controls the energy storage power unit through optical fiber communication, converting the DC power stored in the battery into AC power and vice versa, thus realizing bidirectional flow of electrical energy.

3. A gas turbine black start system based on a high-voltage direct-connected energy storage converter according to claim 1, characterized in that, The energy storage power unit transmits its information to the high-voltage direct-connected energy storage converter control system, enabling the high-voltage direct-connected energy storage converter control system to monitor and protect the energy storage power unit in real time.

4. A gas turbine black start system based on a high-voltage direct-connected energy storage converter according to claim 1, characterized in that, The rectifier circuit includes AC / DC converters AC / DC1 and AC / DC2, the DC circuit includes reactor L3, and the inverter circuit includes DC / AC converter. The split transformer T is connected to the AC side of AC-DC converter AC / DC1 and AC-DC converter AC / DC2 respectively. The DC side of AC-DC converter AC / DC1 and AC-DC converter AC / DC2 are connected in series and connected to DC-AC converter DC / AC through reactor L3.

5. A gas turbine black start system based on a high-voltage direct-connected energy storage converter according to claim 1, characterized in that, It also includes a gas turbine control system, which sends voltage and current commands to the high-voltage direct-connected energy storage converter control system of the high-voltage direct-connected energy storage converter and the static start frequency converter control system of the static start frequency converter.

6. A gas turbine black start system based on a high-voltage direct-connected energy storage converter according to claim 1, characterized in that, The three-phase voltage and current signals on the output side of the high-voltage direct-connected energy storage converter, as well as the input current signal of the static start frequency converter, are all connected to the sampling interface of the high-voltage direct-connected energy storage converter through sensors.

7. A gas turbine black start method based on a high-voltage direct-connected energy storage converter, implemented based on the gas turbine black start system based on a high-voltage direct-connected energy storage converter as described in any one of claims 1-6, characterized in that, The gas turbine black start method based on a high-voltage direct-connected energy storage converter includes the following steps: S1. With circuit breakers QF2, QF3, QF4 and QF5 closed, start the diesel generator to the power frequency so that the high-voltage direct-connected energy storage converter completes pre-charging and is in hot standby mode. S2. Start the high-voltage direct-connected energy storage converter and the static starter frequency converter, and drive the gas turbine to start through the static starter frequency converter; use the high-voltage direct-connected energy storage converter to detect the three-phase voltage and current on the output side in real time, and at the same time detect the input side current of the static starter frequency converter. S3. Obtain the voltage angle through the phase-locked loop module, calculate the active component of the voltage and the active component of the current on the input side of the high-voltage direct-connected energy storage converter based on the input voltage and current of the high-voltage direct-connected energy storage converter, and calculate the active component of the current and the reactive component of the current on the input side of the static start frequency converter based on the input current of the static start frequency converter. S4. Based on the voltage and current commands of the gas turbine control system, calculate the compensation active current command and compensation reactive current command of the high-voltage direct-connected energy storage converter; calculate the three-phase output voltage command of the high-voltage direct-connected energy storage converter based on coordinate transformation. S5, the high-voltage direct-connected energy storage converter sends the calculation results to the energy storage power unit, and each stage of the energy storage power unit outputs pulses to realize reactive and active power compensation on the input side of the static start frequency converter.

8. A gas turbine black start method based on a high-voltage direct-connected energy storage converter according to claim 7, characterized in that, The high-voltage direct-connected energy storage converter has the ability to provide reactive and active power support for short periods of time and has a redundancy design function. Under the condition that a preset number of energy storage power units fail, it can bypass the faulty energy storage power units and continue to complete the reactive and active power compensation function on the input side of the static start frequency converter.

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