Four quadrant converter control method integrating grid simulator and motor drive functionality

Abstract

The application discloses a four-quadrant converter control method integrating power grid simulator and motor drive functions, and comprises the following steps: in the power grid simulator mode, sampling the current of the filter capacitor in the LC filter; multiplying the sampled current value with the capacitor current feedback coefficient, and subtracting the output of the voltage loop PI controller of the filter capacitor to perform PWM modulation; determining the synthesized reference voltage corresponding to the output voltage of the actual synchronous machine according to the preset rated active power and the active power of the virtual synchronous machine, and the preset rated reactive power and the reactive power of the virtual synchronous machine; in the motor drive frequency converter mode, sampling the current of the filter capacitor in the LC filter; multiplying the sampled current value with the capacitor current feedback coefficient, and subtracting the output of the voltage loop PI controller of the filter capacitor to perform PWM modulation, and controlling the rotating speed and torque of the motor, and the application can be widely applied to the field of grid-connected control and motor control.

Description

Technical Field

[0001] This invention relates to the fields of grid-connected control and motor control technology, and in particular to a four-quadrant converter control method that integrates a grid simulator and motor drive functions. Background Technology

[0002] Currently, grid simulators and motor drive frequency converters are two separate devices, while some users require both. The current solution is to purchase two sets of equipment, which undoubtedly increases investment costs and laboratory installation space. The main drawbacks of existing technology are the lack of research integrating these two functions into one unit, the absence of equipment manufacturers offering single-unit solutions that combine both functions, and the absence of existing grid simulators that can simulate the characteristics of grid synchronous generators. Summary of the Invention

[0003] In view of this, embodiments of the present invention provide a four-quadrant converter control method that integrates a power grid simulator and a motor drive function, aiming to realize both the functions of a power grid simulator and a motor drive frequency converter through the same circuit, while reducing the size of the equipment.

[0004] One aspect of this invention provides a four-quadrant converter control method integrating a power grid simulator and motor drive functions, comprising:

[0005] In the power grid simulator mode, the active and reactive power of the virtual synchronous machine are acquired. Based on the preset rated active power and the active power of the virtual synchronous machine, as well as the preset rated reactive power and the reactive power of the virtual synchronous machine, a composite reference voltage that matches the actual synchronous machine is determined. The current of the filter capacitor in the LC filter is sampled to obtain a first sampled current value. The first sampled current value is multiplied by a preset first feedback coefficient of the capacitor current to obtain a first coefficient. The difference between the first coefficient and the output of the voltage loop PI controller of the filter capacitor is calculated to obtain a second coefficient, so as to perform PWM modulation based on the second coefficient.

[0006] In motor drive inverter mode, the current of the filter capacitor in the LC filter is sampled to obtain a second sampled current value; the second sampled current value is multiplied by a preset second feedback coefficient of capacitor current to obtain a third coefficient, and the difference between the third coefficient and the output of the current loop PI controller of the filter capacitor is obtained to obtain a fourth coefficient, so as to perform PWM modulation according to the fourth coefficient and control the speed and torque of the motor.

[0007] Preferably, determining the composite reference voltage that matches the actual synchronous machine based on the preset rated active power and the active power of the virtual synchronous machine, and the preset rated reactive power and the reactive power of the virtual synchronous machine, includes:

[0008] Based on the preset rated active power and the active power of the virtual synchronous machine, as well as the preset rated reactive power and the reactive power of the virtual synchronous machine, a composite reference voltage that matches the inertia, damping, and frequency of the actual synchronous machine is determined.

[0009] Preferably, in the power grid simulator mode, it further includes:

[0010] The grid-connected device under test is driven by the reference synthesized voltage.

[0011] Another aspect of this invention provides a four-quadrant converter control circuit integrating a power grid simulator and motor drive functions, comprising:

[0012] Transformer, three-phase PWM rectifier, DC bus, three single-phase inverters, three LC filters, load motor, motor under test, motor drive controller and power supply;

[0013] The transformer is a three-phase isolation transformer. One end of the transformer is connected to the power grid, and the other end is connected to one end of the three-phase PWM rectifier. The other end of the three-phase PWM rectifier is connected to one end of each single-phase inverter via the DC bus. The other end of each single-phase inverter is connected to one end of an LC filter. In the grid simulator mode, the other end of each LC filter is used to connect to the grid-connected device under test. In the motor drive inverter mode, the other end of each LC filter is connected to the stator of the load motor. The rotor of the load motor is connected to the rotor of the motor under test via a coupling. One end of the motor drive controller is connected to the stator of the motor under test, and the other end of the motor drive controller is connected to the power supply.

[0014] Preferably, if the transformer is a high-frequency isolation transformer, one end of the three-phase PWM rectifier is connected to the power grid, and the other end is connected to one end of the high-frequency isolation transformer through the first DC bus. The other end of the high-frequency isolation transformer is connected to one end of each of the single-phase inverters through the second DC bus.

[0015] Another aspect of this invention provides a four-quadrant converter control device integrating a power grid simulator and motor drive functions, comprising:

[0016] The first control unit is used to acquire the active power and reactive power of the virtual synchronous machine in the power grid simulator mode; determine a composite reference voltage that matches the actual synchronous machine based on the preset rated active power and the active power of the virtual synchronous machine, and the preset rated reactive power and the reactive power of the virtual synchronous machine; sample the current of the filter capacitor in the LC filter to obtain a first sampled current value; multiply the first sampled current value with a preset first feedback coefficient of the capacitor current to obtain a first coefficient, and subtract it from the output of the voltage loop PI controller of the filter capacitor to obtain a second coefficient, so as to perform PWM modulation according to the second coefficient;

[0017] The second control unit is used to sample the current of the filter capacitor in the LC filter in the motor drive inverter mode to obtain a second sampled current value; to product the second sampled current value with a preset second feedback coefficient of capacitor current to obtain a third coefficient, and to subtract the output of the current loop PI controller of the filter capacitor to obtain a fourth coefficient, so as to perform PWM modulation according to the fourth coefficient and control the speed and torque of the motor.

[0018] Preferably, the first control unit includes:

[0019] The voltage characteristic control unit is used to determine a composite reference voltage that matches the inertia, damping, and frequency of the actual synchronous machine based on the preset rated active power and the active power of the virtual synchronous machine, as well as the preset rated reactive power and the reactive power of the virtual synchronous machine.

[0020] Preferably, the first control unit is further configured to drive the grid-connected device under test with the reference synthesized voltage.

[0021] Another aspect of the present invention provides an electronic device, including a processor and a memory;

[0022] The memory is used to store programs;

[0023] The processor executes the program to implement the above-described method.

[0024] Another aspect of this invention provides a computer-readable storage medium storing a program that is executed by a processor to implement the above-described method.

[0025] This invention also discloses a computer program product or computer program, which includes computer instructions stored in a computer-readable storage medium. A processor of a computer device can read the computer instructions from the computer-readable storage medium and execute the computer instructions, causing the computer device to perform the method described above.

[0026] In grid simulator mode, this invention can determine a composite reference voltage that matches the output voltage of an actual synchronous generator based on active and reactive power, thus simulating the voltage characteristics of a grid synchronous generator. Simultaneously, in motor drive inverter mode, the motor speed and torque can be controlled based on the sampled current value of the filter capacitor, the feedback coefficient of the capacitor current, and the output of the voltage loop PI controller. Furthermore, after PWM modulation with a fourth coefficient, the electrical resonance introduced by the LC filter can be suppressed. In other words, while achieving motor speed and torque control, the resonance problem introduced by the LC filter can be effectively suppressed. Moreover, both modes are implemented in the same circuit, eliminating the need for separate implementations in two different circuits, thereby reducing the size of the equipment. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 A flowchart illustrating a four-quadrant converter control method integrating a power grid simulator and motor drive functions, provided in an embodiment of the present invention;

[0029] Figure 2 An example circuit diagram of a four-quadrant converter control circuit integrating a power grid simulator and motor drive functions is provided for an embodiment of the present invention;

[0030] Figure 3 An example circuit diagram of a power grid simulator provided for an embodiment of the present invention;

[0031] Figure 4 A structural topology diagram of the inverter side of a power grid simulator provided in an embodiment of the present invention;

[0032] Figure 5 An inner loop control block diagram provided in an embodiment of the present invention;

[0033] Figure 6 An outer loop control block diagram of a virtual synchronizer provided in an embodiment of the present invention;

[0034] Figure 7 A topology diagram of the inverter stage of the main circuit of a power grid simulator provided in an embodiment of the present invention;

[0035] Figure 8 A control block diagram of the inner current loop provided in an embodiment of the present invention;

[0036] Figure 9A system control block diagram for motor speed-electromagnetic torque control provided in an embodiment of the present invention;

[0037] Figure 10 An example diagram of a power grid simulator algorithm provided in an embodiment of the present invention;

[0038] Figure 11 A waveform diagram of system power and frequency during a sudden load change is provided in an embodiment of the present invention;

[0039] Figure 12 An example diagram of a motor drive algorithm provided in an embodiment of the present invention;

[0040] Figure 13 A waveform diagram of motor speed and torque under sudden load change using capacitor current feedback is provided as an embodiment of the present invention;

[0041] Figure 14 A waveform diagram of the stator voltage and current of a motor under a sudden load change using capacitor current feedback is provided as an embodiment of the present invention.

[0042] Figure 15 A waveform diagram of stator voltage and current when the system becomes unstable without capacitor current feedback under load sudden change, provided as an embodiment of the present invention;

[0043] Figure 16 This is a structural block diagram of a four-quadrant converter control device that integrates a power grid simulator and motor drive functions, provided as an embodiment of the present invention. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0045] Reference Figure 1 This invention provides a four-quadrant converter control method integrating a power grid simulator and motor drive functions, specifically including the following:

[0046] In the power grid simulator mode, the active and reactive power of the virtual synchronous machine are acquired. Based on the preset rated active power and the active power of the virtual synchronous machine, as well as the preset rated reactive power and the reactive power of the virtual synchronous machine, a composite reference voltage that matches the actual synchronous machine is determined. The current of the filter capacitor in the LC filter is sampled to obtain a first sampled current value. The first sampled current value is multiplied by a preset first feedback coefficient of the capacitor current to obtain a first coefficient, and the difference between this first coefficient and the output of the voltage loop PI controller of the filter capacitor is obtained to obtain a second coefficient, so that PWM modulation is performed according to the second coefficient.

[0047] In one alternative implementation, the inertia, damping, and frequency of the reference synthesized reference voltage can be matched with the output voltage of the actual synchronous machine.

[0048] The obtained reference synthesized voltage can then be used to drive the connected grid-connected device under test.

[0049] In motor drive inverter mode, the current of the filter capacitor in the LC filter is sampled to obtain a second sampled current value; the second sampled current value is multiplied by a preset second feedback coefficient of capacitor current to obtain a third coefficient, and the difference between the third coefficient and the output of the current loop PI controller of the filter capacitor is obtained to obtain a fourth coefficient, so as to perform PWM modulation according to the fourth coefficient and control the speed and torque of the motor.

[0050] This invention proposes a four-quadrant converter control method that integrates a power grid simulator and a motor drive function. It aims to achieve both power grid simulation and motor drive functions using the same hardware topology circuit and different software control algorithms.

[0051] The above hardware topology can be referred to Figure 2 This invention provides a four-quadrant converter control circuit that integrates a power grid simulator and motor drive functions. The circuit may include: a transformer, a three-phase PWM rectifier, a DC bus, three single-phase inverters, three LC filters, a load motor, a motor under test, a motor drive controller, and a power supply.

[0052] The transformer is a three-phase isolation transformer. One end of the transformer is connected to the power grid, and the other end is connected to one end of a three-phase PWM rectifier. The other end of the three-phase PWM rectifier is connected to one end of each single-phase inverter via a DC bus. The other end of each single-phase inverter is connected to one end of an LC filter. In the grid simulator mode, the other end of each LC filter is used to connect to the grid-connected device under test. In the motor drive inverter mode, the other end of each LC filter is connected to the stator end of the load motor. The rotor end of the load motor is connected to the rotor end of the motor under test via a coupling. One end of the motor drive controller is connected to the stator end of the motor under test, and the other end of the motor drive controller is connected to the power supply.

[0053] It should be noted that, Figure 2The electrical isolation scheme using a power frequency transformer installed on the input side is used as an example. Other electrical isolation schemes, such as installing a high-frequency transformer for isolation at the DC bus, involve connecting one end of the three-phase PWM rectifier to the power grid and the other end to one end of the high-frequency isolation transformer via the first DC bus. The other end of the high-frequency isolation transformer is then connected to one end of each single-phase inverter via the second DC bus. Using a high-frequency transformer for isolation can reduce the size and weight of the equipment, thereby increasing the power density. Many other implementation schemes of the hardware topology of this invention can also be implemented, which are not listed here.

[0054] The power grid simulator requires bidirectional energy flow. The main circuit uses dual PWM converters to ensure four-quadrant operation. The main circuit topology is as follows: Figure 3 As shown. The front-end uses a PWM rectifier to output a stable DC voltage as the input to the rear-end. The rear-end uses three independent single-phase inverters to form a three-phase system, and the output filtering stage uses an LC filter to simulate the single / three-phase voltage output of the power grid.

[0055] Reference Figure 4 This invention provides a structural topology for the inverter side of a power grid simulator. Due to the three-phase symmetry of the system, only one phase is analyzed here.

[0056] Considering that LC filters introduce electrical resonance, this invention employs capacitor current feedback to suppress it. Capacitor current feedback is equivalent to connecting a virtual resistor in parallel across the filter capacitor. This virtual resistor suppresses the electrical resonance phenomenon generated by the filter, thereby enhancing system stability. Figure 5 This is the inner loop control block diagram used in this invention, where R is the line resistance and L is the line resistance. c For inverter-side inductance, C f K1 is the capacitor current feedback coefficient, and K2 is the filter capacitor. The capacitor current is sampled in real time in the digital controller, multiplied by the capacitor current feedback coefficient K1, and then the difference between this sampled current and the output of the voltage loop PI controller is used for PWM modulation, thus realizing the capacitor current feedback algorithm.

[0057] G h (s) is a zero-order hold (ZOH), and its transfer function is as follows:

[0058]

[0059] Since real power grids are composed of large synchronous generators, changes in their output power lead to changes in the electromagnetic torque of the synchronous generators, which in turn affect the generator speed. This phenomenon causes changes in grid voltage and frequency. To enable the power grid simulator to possess the characteristics of a synchronous generator in the power grid, this invention employs a virtual synchronous machine control strategy to simulate inertia and damping, and to regulate grid voltage and frequency. The virtual synchronous machine control strategy refers to simulating the working characteristics of a real synchronous generator by constructing its voltage and frequency characteristic equations in the controller, thereby making the power grid behave similarly to a synchronous generator. The outer loop control block diagram of the virtual synchronous machine is shown below. Figure 6 As shown.

[0060] Where θ1 is the output angle, ω0 is the rated angular frequency, H1 is the inertial constant, D1 is the damping coefficient, and K... Q P is the droop factor of reactive voltage. 1ref P1 is the rated active power, and Q is the active power output of the virtual synchronous machine. 1ref Q1 is the rated value of reactive power, and Q2 is the reactive power output of the virtual synchronous machine.

[0061] use Figure 3 The main circuit shown drives the motor, and the topology of its inverter stage is as follows: Figure 7 As shown, this introduces electrical resonance. To suppress electrical resonance, this invention also employs an active damping method with capacitor current feedback. The capacitor current is sampled in real time in the digital controller, multiplied by the capacitor current feedback coefficient K, and then the difference between this sampled current and the output of the current loop PI controller is used for PWM modulation. The control block diagram of the digital control of the inner current loop is shown below. Figure 8 As shown, where L m K represents the inductance on the motor side, and K is the capacitor current feedback coefficient.

[0062] Will Figure 8 The inner current loop shown is equivalent to G. ce (s), the system control block diagram for motor speed-electromagnetic torque control is as follows: Figure 9 As shown, where G piω (s) is a PI controller, p is the number of pole pairs, and λ mpm For magnetic flux linkage, 1 / K T =1.5·p·λ mpm J is the inertia of the load motor.

[0063] To describe the invention in more detail, specific examples will be used to illustrate its practical application.

[0064] The proposed power grid simulator algorithm was verified in PLECS simulation software. The overall result is as follows: Figure 10 As shown.

[0065] In the simulation, the power and frequency waveforms of the power grid simulator under sudden load changes are as follows: Figure 11 As shown.

[0066] Simulation results show that the grid simulator's rated frequency is 50Hz. At 0.5 seconds, the load abruptly changes from 1300W to 2600W, and the simulator's frequency begins to decrease. Because the virtual synchronous machine control scheme provides inertia and damping to the system, the frequency of the grid simulator decreases slowly, giving it the characteristics of a synchronous generator.

[0067] The proposed motor drive algorithm was verified in PLECS simulation software, and the overall result is as follows: Figure 12 As shown.

[0068] In the simulation, the waveforms of motor voltage, current, speed, and electromagnetic torque were compared when the motor was driven by a power grid simulator topology under sudden load changes, with and without capacitor current feedback to suppress resonance. The results are shown below. Figure 13 , Figure 14 and Figure 15 As shown.

[0069] according to Figure 13 It can be seen that when the load changes abruptly, this control algorithm can quickly stabilize the system with minimal fluctuations in electromagnetic torque and speed. Based on simulation results... Figure 14 Figure 15 It can be seen that when the load changes abruptly, the active damping algorithm using capacitor current feedback can effectively suppress electrical resonance.

[0070] Reference Figure 16 This invention provides a four-quadrant converter control device integrating a power grid simulator and motor drive functions, comprising:

[0071] The first control unit is used to acquire the active power and reactive power of the virtual synchronous machine in the power grid simulator mode; determine a composite reference voltage that matches the actual synchronous machine based on the preset rated active power and the active power of the virtual synchronous machine, and the preset rated reactive power and the reactive power of the virtual synchronous machine; sample the current of the filter capacitor in the LC filter to obtain a first sampled current value; multiply the first sampled current value with a preset first feedback coefficient of the capacitor current to obtain a first coefficient, and subtract it from the output of the voltage loop PI controller of the filter capacitor to obtain a second coefficient, so as to perform PWM modulation according to the second coefficient;

[0072] The second control unit is used to sample the current of the filter capacitor in the LC filter in the motor drive inverter mode to obtain a second sampled current value; to product the second sampled current value with a preset second feedback coefficient of capacitor current to obtain a third coefficient, and to subtract the output of the current loop PI controller of the filter capacitor to obtain a fourth coefficient, so as to perform PWM modulation according to the fourth coefficient and control the speed and torque of the motor.

[0073] This invention also discloses a computer program product or computer program, which includes computer instructions stored in a computer-readable storage medium. A processor of a computer device can read the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, causing the computer device to perform... Figure 1 The method shown.

[0074] In some alternative embodiments, the functions / operations mentioned in the block diagrams may not occur in the order shown in the operation diagrams. For example, depending on the functions / operations involved, two consecutively shown blocks may actually be executed substantially simultaneously, or the blocks may sometimes be executed in reverse order. Furthermore, the embodiments presented and described in the flowcharts of this invention are provided by way of example to provide a more comprehensive understanding of the technology. The disclosed methods are not limited to the operations and logic flows presented herein. Alternative embodiments are contemplated in which the order of various operations is altered and sub-operations described as part of a larger operation are executed independently.

[0075] Furthermore, although the invention has been described in the context of functional modules, it should be understood that, unless otherwise stated, one or more of the described functions and / or features may be integrated into a single physical device and / or software module, or one or more functions and / or features may be implemented in a separate physical device or software module. It is also understood that a detailed discussion of the actual implementation of each module is unnecessary for understanding the invention. Rather, given the properties, functions, and internal relationships of the various functional modules in the apparatus disclosed herein, the actual implementation of the module will be understood within the scope of conventional skill of an engineer. Therefore, those skilled in the art can implement the invention as set forth in the claims using ordinary techniques without excessive experimentation. It is also understood that the specific concepts disclosed are merely illustrative and not intended to limit the scope of the invention, which is determined by the full scope of the appended claims and their equivalents.

[0076] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, essentially, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0077] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device.

[0078] More specific examples of computer-readable media (a non-exhaustive list) include: electrical connections (electronic devices) having one or more wires, portable computer disk drives (magnetic devices), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Furthermore, computer-readable media can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in computer memory.

[0079] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0080] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "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.

[0081] 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.

[0082] The above is a detailed description of the preferred embodiments of the present invention. However, the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of the present invention.

Claims

1. A four-quadrant converter control method integrating a power grid simulator and motor drive functions, characterized in that, include: In the power grid simulator mode, the active power and reactive power of the virtual synchronous machine are obtained, and a composite reference voltage that matches the actual synchronous machine is determined based on the preset rated active power and the active power of the virtual synchronous machine, as well as the preset rated reactive power and the reactive power of the virtual synchronous machine. The current of the filter capacitor in the LC filter is sampled to obtain a first sampled current value; the first sampled current value is multiplied by a preset first feedback coefficient of the capacitor current to obtain a first coefficient, and the difference between the first coefficient and the output of the voltage loop PI controller of the filter capacitor is obtained to obtain a second coefficient, so as to perform PWM modulation according to the second coefficient; In motor drive inverter mode, the current of the filter capacitor in the LC filter is sampled to obtain a second sampled current value; the second sampled current value is multiplied by a preset second feedback coefficient of capacitor current to obtain a third coefficient, and the difference between the third coefficient and the output of the current loop PI controller of the filter capacitor is obtained to obtain a fourth coefficient, so as to perform PWM modulation according to the fourth coefficient and control the speed and torque of the motor.

2. The four-quadrant converter control method integrating a power grid simulator and motor drive function according to claim 1, characterized in that, The step of determining a composite reference voltage that matches the actual synchronous machine based on preset rated active power and the active power of the virtual synchronous machine, and preset rated reactive power and the reactive power of the virtual synchronous machine, includes: Based on the preset rated active power and the active power of the virtual synchronous machine, as well as the preset rated reactive power and the reactive power of the virtual synchronous machine, a composite reference voltage that matches the inertia, damping, and frequency of the actual synchronous machine is determined.

3. The four-quadrant converter control method integrating a power grid simulator and motor drive function according to claim 1, characterized in that, The power grid simulator mode also includes: The grid-connected device under test is driven by the reference synthesized voltage.

4. A four-quadrant converter control device integrating a power grid simulator and motor drive functions, characterized in that, include: The first control unit is used to acquire the active power and reactive power of the virtual synchronous machine in the power grid simulator mode, and determine the composite reference voltage that matches the actual synchronous machine based on the preset rated active power and the active power of the virtual synchronous machine, as well as the preset rated reactive power and the reactive power of the virtual synchronous machine. The current of the filter capacitor in the LC filter is sampled to obtain a first sampled current value; the first sampled current value is multiplied by a preset first feedback coefficient of the capacitor current to obtain a first coefficient, and the difference between the first coefficient and the output of the voltage loop PI controller of the filter capacitor is obtained to obtain a second coefficient, so as to perform PWM modulation according to the second coefficient; The second control unit is used to sample the current of the filter capacitor in the LC filter in the motor drive inverter mode to obtain the second sampled current value. The second sampled current value is multiplied by the preset capacitor current second feedback coefficient to obtain the third coefficient, and the difference is taken with the output of the current loop PI controller of the filter capacitor to obtain the fourth coefficient, so as to perform PWM modulation according to the fourth coefficient and control the speed and torque of the motor.

5. The four-quadrant converter control device integrating a power grid simulator and motor drive function according to claim 4, characterized in that, The first control unit includes: The voltage characteristic control unit is used to determine a composite reference voltage that matches the inertia, damping, and frequency of the actual synchronous machine based on the preset rated active power and the active power of the virtual synchronous machine, as well as the preset rated reactive power and the reactive power of the virtual synchronous machine.

6. The four-quadrant converter control device integrating a power grid simulator and motor drive function according to claim 4, characterized in that, The first control unit is also configured to drive the grid-connected device under test with the reference composite voltage.

7. An electronic device, characterized in that, Including the processor and memory; The memory is used to store programs; The processor executes the program to implement the method as described in any one of claims 1 to 3.

8. A computer-readable storage medium, characterized in that, The storage medium stores a program that is executed by a processor to implement the method as described in any one of claims 1 to 3.

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