A multi-time scale virtual synchronous machine system based on a solid-state transformer and a control method thereof

Abstract

A kind of multi-time scale virtual synchronous machine control method based on solid-state transformer, comprising the following steps: step S1: constructing virtual synchronizer, the output of equipment of different time scale is simulated by the virtual synchronizer as first data;Wherein different time scale equipment includes: rotor, damping winding and excitation system;Step S2: the control parameters of different time scale are obtained by the first data respectively, to obtain second data;Step S3: control solid-state frequency converter by the second data.Make solid-state transformer under power grid disturbance can provide phased collaborative support like real synchronous machine, especially virtual damping winding ring is specially aimed at frequency change rate and 10Hz above oscillation frequency band produces fast phase compensation, effectively suppresses the subsynchronous oscillation and frequency rapid fluctuation that traditional VSM is easy to cause, significantly improves small disturbance stability.

Description

Technical Field

[0001] This invention relates to the field of solid-state transformer control technology, and in particular to a multi-time-scale virtual synchronous machine system based on solid-state transformers and its control method. Background Technology

[0002] With the rapid increase in the proportion of renewable energy generation, problems such as decreased inertia and weakened disturbance immunity of power systems are becoming increasingly prominent. Virtual Synchronous Machine (VSM) technology has emerged to address this issue, aiming to enable power electronic converters to possess the external characteristics of synchronous generators, providing inertial and damping support for the power grid.

[0003] Currently, mainstream VSM technology has the following limitations: Classical Virtual Synchronous Machines (VSMs) only simulate the outermost mechanical rotor of a synchronous generator. During simulation, control response is based on the "rotor oscillation equation." However, the rotor's moment of inertia is large, requiring a certain amount of time to react to external changes. This results in a delay in feedback speed, limiting existing VSMs to control responses on a second-level scale. They are ineffective against subsynchronous oscillations above 10Hz and high-frequency noise. Therefore, there is an urgent need for a virtual synchronous machine control method capable of achieving millisecond-hundred-millisecond-level response. Summary of the Invention

[0004] To address the aforementioned shortcomings, the present invention aims to propose a multi-time-scale virtual synchronous machine system based on a solid-state transformer and its control method.

[0005] To achieve this objective, the present invention adopts the following technical solution: a multi-time-scale virtual synchronous machine control method based on a solid-state transformer, comprising the following steps: Step S1: Construct a virtual synchronizer to simulate device outputs at different time scales, which will serve as the first data. The equipment at different time scales includes: rotor, damping winding, and excitation system; Step S2: Obtain control parameters at different time scales using the first data to obtain the second data; Step S3: Control the solid-state inverter using the second data.

[0006] Preferably, the first parameter is obtained as follows: The virtual synchronizer input of the rotor is expressed as follows: ; J is the virtual moment of inertia. For angular velocity deviation, For virtual mechanical torque, Where D is the electromagnetic torque and D is the initial mechanical damping coefficient; The virtual synchronizer analog input of the damping winding is expressed as follows: ; ; in The damping torque component is simulated by the virtual synchronizer output for the damping winding. This is the proportionality coefficient. and These are the inductance and resistance of the virtual damping winding, respectively; The coupling coefficient between the rate of change of angular velocity and the induced electromotive force is... The output is simulated by a virtual synchronizer for the rotor; The virtual synchronizer analog input of the excitation system is expressed as follows: ; in The virtual synchronizer of the excitation system simulates the no-load potential of the excitation winding. The virtual excitation time constant. The initial no-load potential, For voltage regulation gain, To set the desired voltage value to be maintained, This refers to the voltage amplitude at the output terminal of the solid-state transformer. This is the armature reaction demagnetization coefficient. This is the virtual q-axis current.

[0007] Preferably, the second parameter in step S2 is obtained as follows: The second parameter includes a first sub-parameter and a second sub-parameter; The first sub-parameter acquisition step is as follows: acquire the angular velocity deviation of the virtual synchronizer's simulated output. With a given initial angular velocity With the angular velocity deviation Add to obtain the reference angular velocity ; For the reference angular velocity Integrate to obtain a reference phase angle, and use the reference phase angle as a phase reference; The formula for obtaining the reference phase angle is as follows: , The initial phase angle; The damping torque component is converted into an additional active power modulation. Or it can be converted into a correction factor for the voltage phase angle. , and used as the first superposition parameter; The first superposition parameter is compared with the reference phase angle. The parameters are superimposed to obtain the first sub-parameter; The steps to obtain the second sub-parameter are as follows: Real-time acquisition of the output voltage of the solid-state transformer And the reactance Xs in the virtual synchronizer; Through the output voltage The reference voltage amplitude is obtained by using the reactance Xs in the virtual synchronizer and the no-load potential of the excitation winding. With reference voltage amplitude As the second sub-parameter; in id is the d-axis component of the stator current, and iq is the q-axis component of the stator current.

[0008] Preferably, the specific steps of step S3 are as follows: The second parameter is modulated by PWM to generate a switching signal. The inverter receives the switching signal and outputs it after filtering to obtain the three-phase voltage that needs to be adjusted.

[0009] A multi-time-scale virtual synchronous machine control system based on a solid-state transformer, using the aforementioned multi-time-scale virtual synchronous machine control method based on a solid-state transformer, includes: The virtual synchronizer construction module is used to construct a virtual synchronizer and simulate the output of equipment at different time scales through the virtual synchronizer to obtain the first data; wherein the equipment at different time scales includes: rotor, damping winding and excitation system. The control parameter acquisition module is used to acquire control parameters at different time scales using the first data to obtain the second data; The solid-state inverter control module is used to control the solid-state inverter using the second data.

[0010] Preferably, the virtual synchronizer construction module includes: Rotor simulation unit, used to simulate the virtual synchronizer output of the rotor; The damping winding simulation unit is used to simulate the virtual synchronizer output of the damping winding to obtain the damping torque component. The excitation system simulation unit is used to simulate the virtual synchronizer output of the excitation system and obtain the no-load electromotive force of the excitation winding.

[0011] Preferably, the control parameter acquisition module includes: The first sub-parameter acquisition unit is used to acquire the angular velocity deviation of the virtual synchronizer's analog output, add the given initial angular velocity to the angular velocity deviation to obtain a reference angular velocity, integrate the reference angular velocity to obtain a reference phase angle, and use the reference phase angle as a phase reference; convert the damping torque component into an additional active power modulation amount or a correction amount for the voltage phase angle, as a first superposition parameter; and superimpose the first superposition parameter with the reference phase angle to obtain the first sub-parameter. The second sub-parameter acquisition unit is used to acquire the output voltage of the solid transformer and the reactance in the virtual synchronizer in real time, and obtain the reference voltage amplitude based on the output voltage, the reactance and the no-load potential of the excitation winding, and use the reference voltage amplitude as the second sub-parameter.

[0012] Preferably, the solid-state inverter control module includes: The PWM modulation unit is used to generate a switching signal from the second parameter through PWM modulation; The inverter control unit is used to enable the inverter to receive the switching signal and output the filtered three-phase voltage that needs to be regulated.

[0013] One of the above technical solutions has the following advantages or beneficial effects: The present invention realizes a fine simulation of the dynamics of a synchronous generator across the entire time scale from milliseconds to seconds, enabling the solid-state transformer to provide phased collaborative support like a real synchronous machine under grid disturbances. In particular, the virtual damping winding loop is specifically designed to generate rapid phase compensation for the rate of frequency change and oscillation frequency bands above 10Hz, effectively suppressing the subsynchronous oscillations and rapid frequency fluctuations that are easily caused by traditional VSMs, and significantly improving the stability under small disturbances. Attached Figure Description

[0014] Figure 1 This is a flowchart of one embodiment of the method of the present invention.

[0015] Figure 2 This is a schematic diagram of the structure of one embodiment of the system of the present invention. Detailed Implementation

[0016] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0017] In the description of embodiments of the present invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of embodiments of the present invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0018] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0019] like Figures 1-2 As shown, a multi-time-scale virtual synchronous machine control method based on solid-state transformers includes the following steps: Step S1: Construct a virtual synchronizer to simulate device outputs at different time scales, which will serve as the first data. The equipment at different time scales includes: rotor, damping winding, and excitation system; Step S2: Obtain control parameters at different time scales using the first data to obtain the second data; Step S3: Control the solid-state inverter using the second data.

[0020] To address the limitations of classic Virtual Synchronous Machines (VSMs), which can only achieve second-level response and cannot effectively suppress subsynchronous oscillations above 10Hz and high-frequency noise, this invention not only simulates the rotor mechanical dynamics of a traditional synchronous generator in the virtual synchronous machine, but also further simulates the internal electromagnetic transient processes of the damping winding and excitation system, thereby generating first data containing slow, medium, and fast time scales. The rotor dynamics correspond to second-level mechanical inertia, while the damping winding dynamics correspond to millisecond to hundreds of millisecond-level electromagnetic damping.

[0021] Then, step S2 obtains control parameters at different time scales based on the first data simulated by the virtual synchronizer, specifically including: obtaining the reference phase angle through the rotor motion equation. (Slow scale) The first superposition parameters are obtained through a virtual damping winding circuit model. (Medium scale) The reference voltage amplitude is obtained through a virtual excitation system model and armature reaction equation. (Fast scale), ultimately forming the second data. Step S3 utilizes the fast digital controller (microsecond-level operation cycle) and high switching frequency (kHz-level) power electronic devices of the solid-state transformer (SST) to directly use the first and second sub-parameter values ​​from the second data for PWM modulation of the output stage inverter. Simultaneously, through the input stage converter and DC bus capacitor, inertial energy buffering (second-level) and excitation energy regulation (millisecond-level) are achieved, thereby enabling precise control of the solid-state transformer.

[0022] This invention enables a refined simulation of the dynamics of a synchronous generator across the entire timescale from milliseconds to seconds, allowing the solid-state transformer to provide phased coordinated support under grid disturbances, much like a real synchronous machine. In particular, the virtual damping winding loop is specifically designed to generate rapid phase compensation for the rate of frequency change and oscillation frequency bands above 10Hz, effectively suppressing the subsynchronous oscillations and rapid frequency fluctuations that are easily caused by traditional VSMs, and significantly improving stability under small disturbances.

[0023] Preferably, the first parameter is obtained as follows: The virtual synchronizer input of the rotor is expressed as follows: ; J is the virtual moment of inertia. For angular velocity deviation, This is the virtual mechanical torque (given by the power loop). is the electromagnetic torque (calculated by measurement at the electrical port), and D is the initial mechanical damping coefficient; The virtual synchronizer analog input of the damping winding is expressed as follows: ; ; in The damping torque component is simulated by the virtual synchronizer output for the damping winding. This is the proportionality coefficient. and The inductance and resistance of the virtual damping winding, respectively, determine the response speed and strength of the damping effect; The coupling coefficient between the rate of change of angular velocity and the induced electromotive force is... The output is simulated by a virtual synchronizer for the rotor; The virtual synchronizer analog input of the excitation system is expressed as follows: ; in The virtual synchronizer of the excitation system simulates the no-load potential of the excitation winding. The virtual excitation time constant. The initial no-load potential, For voltage regulation gain, To set the desired voltage value to be maintained, This refers to the voltage amplitude at the output terminal of the solid-state transformer. This is the armature reaction demagnetization coefficient. This is the virtual q-axis current.

[0024] Preferably, the second parameter in step S2 is obtained as follows: The second parameter includes a first sub-parameter and a second sub-parameter; The first sub-parameter acquisition step is as follows: acquire the angular velocity deviation of the virtual synchronizer's simulated output. With a given initial angular velocity With the angular velocity deviation Add to obtain the reference angular velocity ; For the reference angular velocity Integrate to obtain a reference phase angle, and use the reference phase angle as a phase reference; The formula for obtaining the reference phase angle is as follows: , The initial phase angle; The damping torque component is converted into an additional active power modulation. Or it can be converted into a correction factor for the voltage phase angle. , and used as the first superposition parameter; The first superposition parameter is compared with the reference phase angle. The parameters are superimposed to obtain the first sub-parameter; Wherein, the reference phase angle The input is obtained by integrating the rotor equation, which determines the fundamental frequency and slow phase change trend of the output voltage. It simulates the large inertial motion of the synchronous machine rotor, providing a basic inertia support during adjustment to prevent deviation of the adjustment amount. The first superimposed parameter comes from the virtual damping winding model. Since the virtual damping winding model generates data faster, the first superimposed parameter can serve as a shorter-term phase adjustment amount, in conjunction with the phase angle. After superposition, the inverter output voltage phase can both slowly track grid frequency changes (changing according to rotor inertia) and provide millisecond-level phase compensation for instantaneous frequency fluctuations (changing according to the damping winding variation). If the first sub-parameter only uses the reference phase angle... However, adding the first superposition parameter would result in a configuration similar to the existing classical virtual synchronous machine (VSM), which cannot suppress mesoscale disturbances (hundreds of milliseconds). If only the first superposition parameter is used without superimposing it on the reference phase angle, fast phase modulation cannot be achieved due to the bandwidth limitation of the voltage loop. Therefore, superimposing the mesoscale damping as an additional phase onto the slow-scale phase reference is the key to time-scale decoupling, ensuring the high bandwidth and independence of the damping effect.

[0025] Specifically, When the first superposition parameter is the active power modulation amount At that time, it was done by modifying the virtual mechanical torque in the rotor equation. This changes the reference angular velocity. and reference phase angle The generation of .

[0026] and ,in The supplementary coefficient is determined to account for the desired phase compensation range of the system. If the first superposition parameter is the correction amount for the voltage phase angle... Then, the phase angle can be directly adjusted. Superimpose them.

[0027] The steps to obtain the second sub-parameter are as follows: Real-time acquisition of the output voltage of the solid-state transformer And the reactance Xs in the virtual synchronizer; Through the output voltage The reference voltage amplitude is obtained by using the reactance Xs in the virtual synchronizer and the no-load potential of the excitation winding. With reference voltage amplitude As the second sub-parameter; in id is the d-axis component of the stator current, and iq is the q-axis component of the stator current.

[0028] The second sub-parameter is used to simulate the rapid voltage regulation of the synchronous generator excitation system and the demagnetizing effect of the armature reaction. Among them, the no-load potential... The first-order equation of the virtual excitation system is solved in real time, and its inputs include the solid transformer port voltage deviation ΔU. and virtual q-axis current The time constant is set in the millisecond range (e.g., 10~50ms), enabling rapid response to grid voltage fluctuations. The reference voltage amplitude... When calculating and obtaining, it is necessary to subtract... This precisely simulates the direct-axis component of the stator current. The armature reaction voltage drop generated on the synchronous reactor Xs, when the load active current increases, becomes the virtual internal potential and no-load potential. A portion will be automatically deducted, causing the output voltage to naturally decline, which is completely consistent with the "voltage regulation" characteristic of a real synchronous machine.

[0029] Preferably, the specific steps of step S3 are as follows: The second parameter is modulated by PWM to generate a switching signal. The inverter receives the switching signal and outputs it after filtering to obtain the three-phase voltage that needs to be adjusted.

[0030] The formula for obtaining the three-phase voltage is as follows: ; ;

[0031] in This is the first sub-parameter.

[0032] For traditional inertial energy buffering, such as during virtual rotor acceleration / deceleration, the corresponding active power throughput is affected. This energy change is first reflected in the voltage fluctuation of the DC bus capacitor C. By adjusting the three-phase voltage, the output voltage of the solid-state transformer is regulated to smooth out voltage fluctuations, thereby providing a real energy buffer for the virtual inertia. This is a second-level energy adjustment process.

[0033] Because the second parameter in this invention also includes data generated by a virtual excitation system, and the data generated by the excitation system is at the millisecond or hundred-millisecond level, the switching signal of this invention can be used for transformer control at the millisecond or hundred-millisecond level. Specifically, the no-load potential of the virtual excitation system... The change in voltage corresponds to the change in energy required to maintain the air gap magnetic field. In solid-state transformers, this manifests as the change in energy required to maintain a specific three-phase voltage level. Therefore, by controlling the no-load potential... By superimposing the second parameter and then converting the change in the second parameter into a fine adjustment of the three-phase voltage reference value, the input stage converter can respond to the excitation command in milliseconds, achieving rapid "electromagnetic" energy regulation.

[0034] A multi-time-scale virtual synchronous machine control system based on a solid-state transformer, using the aforementioned multi-time-scale virtual synchronous machine control method based on a solid-state transformer, includes: The virtual synchronizer construction module is used to construct a virtual synchronizer and simulate the output of equipment at different time scales through the virtual synchronizer to obtain the first data; wherein the equipment at different time scales includes: rotor, damping winding and excitation system. The control parameter acquisition module is used to acquire control parameters at different time scales using the first data to obtain the second data; The solid-state inverter control module is used to control the solid-state inverter using the second data.

[0035] Preferably, the virtual synchronizer construction module includes: Rotor simulation unit, used to simulate the virtual synchronizer output of the rotor; The damping winding simulation unit is used to simulate the virtual synchronizer output of the damping winding to obtain the damping torque component. The excitation system simulation unit is used to simulate the virtual synchronizer output of the excitation system and obtain the no-load electromotive force of the excitation winding.

[0036] Preferably, the control parameter acquisition module includes: The first sub-parameter acquisition unit is used to acquire the angular velocity deviation of the virtual synchronizer's analog output, add the given initial angular velocity to the angular velocity deviation to obtain a reference angular velocity, integrate the reference angular velocity to obtain a reference phase angle, and use the reference phase angle as a phase reference; convert the damping torque component into an additional active power modulation amount or a correction amount for the voltage phase angle, as a first superposition parameter; and superimpose the first superposition parameter with the reference phase angle to obtain the first sub-parameter. The second sub-parameter acquisition unit is used to acquire the output voltage of the solid transformer and the reactance in the virtual synchronizer in real time, and obtain the reference voltage amplitude based on the output voltage, the reactance and the no-load potential of the excitation winding, and use the reference voltage amplitude as the second sub-parameter.

[0037] Preferably, the solid-state inverter control module includes: The PWM modulation unit is used to generate a switching signal from the second parameter through PWM modulation; The inverter control unit is used to enable the inverter to receive the switching signal and output the filtered three-phase voltage that needs to be regulated.

[0038] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0039] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A multi-time-scale virtual synchronous machine control method based on solid-state transformers, characterized in that, The steps include the following: Step S1: Construct a virtual synchronizer to simulate device outputs at different time scales, which will serve as the first data. The equipment at different time scales includes: rotor, damping winding, and excitation system; Step S2: Obtain control parameters at different time scales using the first data to obtain the second data; Step S3: Control the solid-state inverter using the second data.

2. The multi-time-scale virtual synchronous machine control method based on a solid-state transformer according to claim 1, characterized in that, The first parameter is obtained as follows: The virtual synchronizer input of the rotor is expressed as follows: ； J is the virtual moment of inertia. For angular velocity deviation, For virtual mechanical torque, Where D is the electromagnetic torque and D is the initial mechanical damping coefficient; The virtual synchronizer analog input of the damping winding is expressed as follows: ； ； in The damping torque component is simulated by the virtual synchronizer output for the damping winding. This is the proportionality coefficient. and These are the inductance and resistance of the virtual damping winding, respectively; The coupling coefficient between the rate of change of angular velocity and the induced electromotive force is... The output is simulated by a virtual synchronizer for the rotor; The virtual synchronizer analog input of the excitation system is expressed as follows: ； in The virtual synchronizer of the excitation system simulates the no-load potential of the excitation winding. The virtual excitation time constant. The initial no-load potential, For voltage regulation gain, To set the desired voltage value to be maintained, This refers to the voltage amplitude at the output terminal of the solid-state transformer. This is the armature reaction demagnetization coefficient. This is the virtual q-axis current.

3. The multi-time-scale virtual synchronous machine control method based on a solid-state transformer according to claim 2, characterized in that, The second parameter in step S2 is obtained as follows: The second parameter includes a first sub-parameter and a second sub-parameter; The first sub-parameter acquisition step is as follows: acquire the angular velocity deviation of the virtual synchronizer's simulated output. With a given initial angular velocity With the angular velocity deviation Add to obtain the reference angular velocity ; For the reference angular velocity Integrate to obtain a reference phase angle, and use the reference phase angle as a phase reference; The formula for obtaining the reference phase angle is as follows: , The initial phase angle; The damping torque component is converted into an additional active power modulation. Or it can be converted into a correction factor for the voltage phase angle. , and used as the first superposition parameter; The first superposition parameter is compared with the reference phase angle. The parameters are superimposed to obtain the first sub-parameter; The steps to obtain the second sub-parameter are as follows: Real-time acquisition of the output voltage of the solid-state transformer And the reactance Xs in the virtual synchronizer; Through the output voltage The reference voltage amplitude is obtained by using the reactance Xs in the virtual synchronizer and the no-load potential of the excitation winding. With reference voltage amplitude As the second sub-parameter; in id is the d-axis component of the stator current, and iq is the q-axis component of the stator current.

4. The multi-time-scale virtual synchronous machine control method based on a solid-state transformer according to claim 3, characterized in that, The specific steps of step S3 are as follows: The second parameter is modulated by PWM to generate a switching signal. The inverter receives the switching signal and outputs it after filtering to obtain the three-phase voltage that needs to be adjusted.

5. A multi-time-scale virtual synchronous machine control system based on a solid-state transformer, characterized in that, The multi-time-scale virtual synchronous machine control method based on a solid-state transformer as described in any one of claims 1 to 4 includes: The virtual synchronizer construction module is used to construct a virtual synchronizer and simulate the output of equipment at different time scales through the virtual synchronizer to obtain the first data; wherein the equipment at different time scales includes: rotor, damping winding and excitation system. The control parameter acquisition module is used to acquire control parameters at different time scales using the first data to obtain the second data; The solid-state inverter control module is used to control the solid-state inverter using the second data.

6. The multi-time-scale virtual synchronous machine control system based on a solid-state transformer according to claim 5, characterized in that, The virtual synchronizer construction module includes: Rotor simulation unit, used to simulate the virtual synchronizer output of the rotor; The damping winding simulation unit is used to simulate the virtual synchronizer output of the damping winding to obtain the damping torque component. The excitation system simulation unit is used to simulate the virtual synchronizer output of the excitation system and obtain the no-load electromotive force of the excitation winding.

7. A multi-time-scale virtual synchronous machine control system based on a solid-state transformer according to claim 5, characterized in that, The control parameter acquisition module includes: The first sub-parameter acquisition unit is used to acquire the angular velocity deviation of the virtual synchronizer's analog output, add the given initial angular velocity to the angular velocity deviation to obtain a reference angular velocity, integrate the reference angular velocity to obtain a reference phase angle, and use the reference phase angle as a phase reference; convert the damping torque component into an additional active power modulation amount or a correction amount for the voltage phase angle, as a first superposition parameter; and superimpose the first superposition parameter with the reference phase angle to obtain the first sub-parameter. The second sub-parameter acquisition unit is used to acquire the output voltage of the solid transformer and the reactance in the virtual synchronizer in real time, and obtain the reference voltage amplitude based on the output voltage, the reactance and the no-load potential of the excitation winding, and use the reference voltage amplitude as the second sub-parameter.

8. A multi-time-scale virtual synchronous machine control system based on a solid-state transformer according to claim 7, characterized in that, The solid-state inverter control module includes: The PWM modulation unit is used to generate a switching signal from the second parameter through PWM modulation; The inverter control unit is used to enable the inverter to receive the switching signal and output the filtered three-phase voltage that needs to be regulated.

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