CN-122026688-A - Three-phase four-bridge arm inverter control method and device based on multi-quasi PR parallel resonance, terminal equipment and storage medium

CN122026688ACN 122026688 ACN122026688 ACN 122026688ACN-122026688-A

Abstract

The invention discloses a control method, a device, terminal equipment and a storage medium of a three-phase four-bridge arm inverter based on multi-quasi PR parallel resonance, and relates to the field of inverter control, wherein the method comprises the steps of scaling three-phase voltage errors of three-phase load voltage and three-phase reference voltage to obtain a proportional control signal, amplifying resonance gain of fundamental wave, first harmonic wave and second harmonic wave to obtain corresponding resonance control signals, and superposing the corresponding resonance control signals in parallel to obtain a current inner loop reference value; and determining the voltage of a neutral line bridge arm according to the output voltage of the three-phase bridge arm, further generating a switch control pulse signal of the bridge arm, and controlling the three-phase four-bridge arm inverter. By implementing the invention, the problem that the output voltage distortion is caused by the fact that the PI control is difficult to adapt to the nonlinear load in the prior art is solved, and the output voltage distortion rate under the nonlinear load is reduced.

Inventors

YUE JINGPENG
ZHANG ZIHAN
AN RANRAN
Wen Qinghuan
CAO DEFA
WANG HAO

Assignees

广东电网有限责任公司
广东电网有限责任公司电力科学研究院

Dates

Publication Date: 20260512
Application Date: 20251124

Claims (10)

1. A three-phase four-bridge arm inverter control method based on multi-quasi PR parallel resonance is characterized by comprising the following steps: acquiring three-phase inductance current, three-phase load voltage and three-phase reference voltage of a three-phase four-bridge arm inverter; According to the three-phase load voltage and the three-phase reference voltage, calculating to obtain a three-phase voltage error; scaling the three-phase voltage error by a preset scaling factor to obtain a scaling control signal; extracting resonant components of a fundamental wave, a first harmonic wave and a second harmonic wave from the three-phase voltage error respectively, and amplifying the resonant components through corresponding preset resonant gains to obtain corresponding resonant control signals, wherein the order of the first harmonic wave is different from that of the second harmonic wave; The control signals of the comparative example and all the resonance control signals are overlapped in parallel to obtain a current inner loop reference value; according to the deviation between the current inner loop reference value and the three-phase inductance current, carrying out current inner loop control by combining with the compensation of the three-phase load current, and determining the output voltage of the three-phase bridge arm; according to the output voltage of the three-phase bridge arm, determining the voltage of the neutral line bridge arm; Generating a switch control pulse signal of a bridge arm according to the output voltage of the three-phase bridge arm and the voltage of the neutral line bridge arm; And controlling the three-phase four-bridge-arm inverter based on the switch control pulse signals of the bridge arms.
2. The method for controlling a three-phase four-leg inverter based on multi-quasi-PR parallel resonance according to claim 1, wherein said preset resonance gain includes a fundamental resonance gain, a first resonance gain, and a second resonance gain; After the resonant components of the fundamental wave, the first harmonic wave and the second harmonic wave are respectively extracted from the three-phase voltage errors, the corresponding resonant control signals are obtained through corresponding preset resonant gain amplification, and the method comprises the following steps: Screening error components of three-phase voltage errors at fundamental wave frequency through a preset fundamental wave resonance controller, and combining fundamental wave resonance gain to obtain a fundamental wave resonance control signal; Screening error components of the three-phase voltage error at the fundamental frequency of a first preset multiple through a preset first resonance controller, and combining a first resonance gain to obtain a resonance control signal of a first harmonic, wherein the first preset multiple is the order of the first harmonic; And screening error components of the three-phase voltage error at the fundamental frequency of a second preset multiple through a preset second resonance controller, and combining a second resonance gain to obtain a resonance control signal of a second harmonic, wherein the second preset multiple is the order of the second harmonic.
3. The method for controlling a three-phase four-leg inverter based on multi-quasi-PR parallel resonance according to claim 1, wherein the determining the three-phase leg output voltage by performing current loop control in combination with compensation of the three-phase load current according to deviation of the current loop reference value and the three-phase inductance current comprises: the deviation between the current inner loop reference value and the three-phase inductance current is input into a preset current controller for gain adjustment, and bridge arm adjustment voltage is generated through preset proportional gain amplification; Converting deviation of bridge arm regulating voltage and three-phase load voltage through preset inductance transfer function to obtain updated three-phase inductance current; And converting the deviation of the updated three-phase inductance current and the three-phase load current through a preset capacitance transfer function to obtain the output voltage of the three-phase bridge arm.
4. The method for controlling a three-phase four-leg inverter based on multi-quasi-PR parallel resonance according to claim 1, wherein determining the neutral-line leg voltage from the three-phase leg output voltage comprises: Determining a single-phase voltage maximum value and a single-phase voltage minimum value from the output voltages of the three-phase bridge arms; obtaining the direct current bus voltage of a three-phase four-bridge arm inverter; Determining a neutral line bridge arm voltage upper limit reference value and a neutral line bridge arm voltage lower limit reference value according to the direct current bus voltage, the single-phase voltage maximum value and the single-phase voltage minimum value; setting a time distribution coefficient; and according to the time distribution coefficient, determining the voltage of the neutral line bridge arm through the linear combination relation of the upper limit reference value of the voltage of the neutral line bridge arm and the lower limit reference value of the voltage of the neutral line bridge arm.
5. The method for controlling a three-phase four-leg inverter based on multi-quasi-PR parallel resonance according to claim 1, wherein generating a switching control pulse signal of a leg according to a three-phase leg output voltage and a neutral line leg voltage comprises: respectively superposing the three-phase bridge arm output voltage and the neutral line bridge arm voltage to obtain a three-phase output phase voltage; Respectively comparing the three-phase output phase voltage and the neutral line bridge arm voltage with a preset triangular carrier; If the a-phase output phase voltage is smaller than a preset triangular carrier, determining that the switching control pulse signal of the a-phase bridge arm is 0, and if the a-phase output phase voltage is not smaller than the preset triangular carrier, determining that the switching control pulse signal of the a-phase bridge arm is 1; if the b-phase output phase voltage is smaller than the preset triangular carrier, determining that the switching control pulse signal of the b-phase bridge arm is 0, and if the b-phase output phase voltage is not smaller than the preset triangular carrier, determining that the switching control pulse signal of the b-phase bridge arm is 1; If the c-phase output phase voltage is smaller than a preset triangular carrier, determining that the switching control pulse signal of the c-phase bridge arm is 0, and if the c-phase output phase voltage is not smaller than the preset triangular carrier, determining that the switching control pulse signal of the c-phase bridge arm is 1; If the voltage of the neutral line bridge arm is smaller than the preset triangular carrier, the switch control pulse signal of the neutral line bridge arm is determined to be 0, and if the voltage of the neutral line bridge arm is not smaller than the preset triangular carrier, the switch control pulse signal of the neutral line bridge arm is determined to be 1.
6. The method for controlling a three-phase four-leg inverter based on multi-quasi-PR parallel resonance according to claim 1, further comprising, after controlling the three-phase four-leg inverter based on a switching control pulse signal of a leg: acquiring a fundamental wave phase voltage effective value and each subharmonic phase voltage effective value of a three-phase four-bridge arm inverter; calculating to obtain the total harmonic distortion percentage of the output voltage according to the effective value of the fundamental wave phase voltage and the effective value of each subharmonic phase voltage; And according to the total harmonic distortion percentage of the output voltage, evaluating the control effectiveness of the three-phase four-bridge arm inverter.
7. The three-phase four-bridge arm inverter control device based on multi-quasi PR parallel resonance is characterized by comprising a signal acquisition module, a voltage error calculation module, a proportion control module, a resonance control module, a parallel superposition module, a current inner loop control module, a neutral line bridge arm voltage determination module, a bridge arm switch signal generation module and a drive control module; the signal acquisition module is used for acquiring three-phase inductance current, three-phase load voltage and three-phase reference voltage of the three-phase four-bridge arm inverter; The voltage error calculation module is used for calculating and obtaining a three-phase voltage error according to the three-phase load voltage and the three-phase reference voltage; the proportional control module is used for scaling the three-phase voltage error through a preset proportional coefficient to obtain a proportional control signal; the resonance control module is used for respectively extracting resonance components of a fundamental wave, a first harmonic wave and a second harmonic wave from the three-phase voltage error, and amplifying the resonance components through corresponding preset resonance gains to obtain corresponding resonance control signals, wherein the order of the first harmonic wave is different from that of the second harmonic wave; The parallel superposition module is used for carrying out parallel superposition on the comparative example control signals and all the resonance control signals to obtain a current inner loop reference value; The current inner loop control module is used for carrying out current inner loop control according to the deviation between the current inner loop reference value and the three-phase inductance current and combining the compensation of the three-phase load current to determine the output voltage of the three-phase bridge arm; the neutral line bridge arm voltage determining module is used for determining the neutral line bridge arm voltage according to the three-phase bridge arm output voltage; The bridge arm switch signal generation module is used for generating switch control pulse signals of the bridge arms according to the three-phase bridge arm output voltage and the neutral line bridge arm voltage; the driving control module is used for controlling the three-phase four-bridge arm inverter based on the switch control pulse signals of the bridge arms.
8. The three-phase four-leg inverter control device based on multi-quasi-PR parallel resonance according to claim 7, further comprising a control performance evaluation module; the control performance evaluation module comprises a phase voltage acquisition unit, a total harmonic distortion calculation unit and a validity evaluation unit; The phase voltage acquisition unit is used for acquiring the fundamental wave phase voltage effective value and each subharmonic phase voltage effective value of the three-phase four-bridge arm inverter; the total harmonic distortion calculation unit is used for calculating the total harmonic distortion percentage of the output voltage according to the fundamental wave phase voltage effective value and each subharmonic phase voltage effective value; the effectiveness evaluation unit is used for evaluating the effectiveness of the control of the three-phase four-bridge arm inverter according to the total harmonic distortion percentage of the output voltage.
9. A terminal device comprising a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, the processor implementing the multi-quasi-PR parallel resonance based three-phase four-leg inverter control method according to any of claims 1-6 when executing the computer program.
10. A computer readable storage medium, characterized in that the computer readable storage medium comprises a stored computer program, wherein the computer program, when run, controls a device in which the computer readable storage medium is located to execute the three-phase four-leg inverter control method based on multi-quasi-PR parallel resonance as claimed in any of claims 1-6.

Description

Three-phase four-bridge arm inverter control method and device based on multi-quasi PR parallel resonance, terminal equipment and storage medium Technical Field The invention relates to the field of inverter control, in particular to a three-phase four-bridge arm inverter control method, device, terminal equipment and storage medium based on multi-quasi PR parallel resonance. Background With the development of new energy power generation and micro-grids, an inverter is used as key equipment in a grid system, and needs to cope with various complex load scenes. The traditional three-phase three-bridge arm inverter is easy to cause voltage distortion under asymmetric load because the neutral point is uncontrollable. Compared with a three-bridge arm, the three-phase four-bridge arm topology realizes direct control of neutral point voltage by adding the fourth bridge arm, and the circuit topology has higher direct current utilization rate, has smaller direct current input capacitance and reduces the asymmetry of three-phase output when unbalanced load. In general, an inductor is added on the neutral line, so that the filtering effect of the output end of the system can be improved, the switching ripple in the line can be restrained, and the harmonic wave of the three-phase voltage can be reduced. At present, the closed-loop control of the three-phase four-bridge arm inverter mostly adopts PI (proportion-integral) control technology, the error can be responded quickly through a proportion link, the steady-state error is eliminated by utilizing an integral link, the direct-current quantity can be tracked without static difference, and meanwhile, the load current interference can be well restrained. However, PI control essentially belongs to linear control, when a system is connected to a nonlinear load, load current generated by the nonlinear load contains abundant harmonic components, the harmonic components are represented as ac quantity under a synchronous rotation coordinate system, the tracking capability of the PI controller on the ac quantity is limited, inherent steady-state errors exist, and the harmonic current becomes a part of output voltage after passing through the output impedance of the system, and finally, the output voltage distortion is caused, so that the electric energy quality is seriously affected. Disclosure of Invention The embodiment of the invention provides a control method, a device, terminal equipment and a storage medium of a three-phase four-bridge arm inverter based on multi-quasi PR parallel resonance, which can solve the problem that the output voltage is distorted due to the fact that PI control is adopted in the prior art and is difficult to adapt to a nonlinear load, and reduce the output voltage distortion rate under the nonlinear load. The embodiment of the invention provides a control method of a three-phase four-bridge arm inverter based on multi-quasi PR parallel resonance, which comprises the following steps: acquiring three-phase inductance current, three-phase load voltage and three-phase reference voltage of a three-phase four-bridge arm inverter; According to the three-phase load voltage and the three-phase reference voltage, calculating to obtain a three-phase voltage error; scaling the three-phase voltage error by a preset scaling factor to obtain a scaling control signal; extracting resonant components of a fundamental wave, a first harmonic wave and a second harmonic wave from the three-phase voltage error respectively, and amplifying the resonant components through corresponding preset resonant gains to obtain corresponding resonant control signals, wherein the order of the first harmonic wave is different from that of the second harmonic wave; The control signals of the comparative example and all the resonance control signals are overlapped in parallel to obtain a current inner loop reference value; according to the deviation between the current inner loop reference value and the three-phase inductance current, carrying out current inner loop control by combining with the compensation of the three-phase load current, and determining the output voltage of the three-phase bridge arm; according to the output voltage of the three-phase bridge arm, determining the voltage of the neutral line bridge arm; Generating a switch control pulse signal of a bridge arm according to the output voltage of the three-phase bridge arm and the voltage of the neutral line bridge arm; And controlling the three-phase four-bridge-arm inverter based on the switch control pulse signals of the bridge arms. Further, the preset resonance gain comprises a fundamental resonance gain, a first resonance gain and a second resonance gain; after respectively extracting resonance components of fundamental wave, first harmonic wave and second harmonic wave from the three-phase voltage error, amplifying the three-phase voltage error by corresponding preset resonance gain to obtain a corresponding re