Research On Simulation System Of Permanent Magnet Synchronous Motor And Its Load

Permanent magnet synchronous motors are widely used in the new energy automobile industry due to their simple structure,small size,and high efficiency.The permanent magnet synchronous motor needs the motor driver to achieve precise control of the motor torque,speed and current when it is running.Therefore,it is necessary to test its performance after the motor driver is developed.The traditional motor driver test program is a motor-towing platform of "motor driver-motor-generator to be tested",where the motor is the controlled motor and the generator is used to simulate the mechanical load of the motor.This solution is costly,fixed parameters and difficult to adjust and test.The process is cumbersome.Aiming at the defects of the above-mentioned motor-to-drag platform test scheme,this article uses a three-phase two-level inverter to simulate the port characteristics of a permanent magnet synchronous motor and its load.The inverter is called a motor simulator.The inverter and the grid-connected inverter together constitute the motor simulation system of the research object of this paper.This article first establishes the mathematical model of the simulation system of the permanent magnet synchronous motor and its load,which provides the basis for the control of each part and the establishment of the model.In the motor simulation system,the motor driver adopts speed-current PI control,the grid-connected inverter adopts voltage-current PI control,and the motor simulator adopts current PI control.Aiming at the shortcomings of poor dynamic performance in the current PI control of the motor simulator,the model predictive current control is used to improve the current closed-loop method and improve the control effect.The voltage control strategy of the motor simulator is summarized and improved.It can realize the simulation of the motor port characteristics without current closed-loop control,and can effectively reduce the number of system sensors and reduce the cost of the system.A simulation model of a motor simulation system based on Matlab/Simulink is built to verify the effectiveness of the control strategy of the motor driver,grid-connected inverter,and motor simulator of the motor simulation system.Finally,in the semi-physical experimental platform based on RTU-BOX and RT-LAB,the semi-physical model of the simulation system of the permanent magnet synchronous motor and its load is established and experimentally verified.The experimental results show that the motor simulation system can simulate the real motor Electrical port characteristics.