Research On Motor Simulator System Based On Parallel Hybrid Converter

Permanent magnet synchronous motors have been widely used due to their advantages such as simple structure,high stability,and high power factor.The traditional testing scheme for motor drivers adopts a motor coupling platform of "motor driver to be tested-target motor-generator",which has drawbacks such as high cost,poor flexibility,and complex experimental process.The power hardware in the loop(PHIL)testing platform using a power converter can achieve the substitution of real motors to complete experimental testing of power levels.This article uses a parallel hybrid converter based motor simulator to connect to the tested motor driver,and simulates the port characteristics of the real target motor without changing the hardware system of the tested motor driver.This article focuses on the research of motor simulators based on parallel hybrid parallel converters,and the main work is as follows:Firstly,by comparing and analyzing the advantages and disadvantages of the current research status of power topology in motor simulators,a high power density parallel hybrid converter(PHC)is adopted as the power topology of the motor simulator.The main power converter is a high-power low-frequency converter,and the parallel converter is a low-power high-frequency cascaded H-Bridge(CHB).The working principle of the H-bridge is analyzed,The traditional phase shifted carrier modulation strategy of CHB;In the basic control of the motor simulation system of a parallel hybrid converter,the motor driver adopts a dual closed-loop control of speed and current,and the main converter and parallel hybrid converter obtain a reference voltage through a current regulator.Then,the causes and effects of the unbalanced DC side capacitor voltage of CHB are analyzed,and the sorting algorithm is used to achieve the DC side capacitor voltage balance.For the two bypass modes in the sorting algorithm,they are evenly distributed,so as to balance the switch loss of H-bridge.During the PWM modulation process of switching devices,the order of modal operation is taken into account,which can reduce the number of switches and reduce switching losses.The absorption ability of CHB to high-frequency current was verified when the parallel hybrid converter was loaded.Analyzed the model prediction of the parallel hybrid converter motor simulator and derived the voltage equation.Consider the dead time effect and compensation scheme during the switching process of the CHB converter.Finally,the RTU-BOX and RT-LAB semi physical array experimental platforms for motor simulation systems based on parallel hybrid converters were built;Analyze the simulation results of the motor simulator system based on parallel hybrid converters,and the simulation results are consistent with the theoretical analysis in the previous chapters;The semi physical experimental results indicate that the parallel hybrid converter motor simulator proposed in this paper can simulate the short-term port characteristics of the real target motor.