Simulation Design Of Standard Parts Of Drive Motor System For EMC Darkroom Evaluation

With the rapid development of electronic technology,the degree of electrification of automobiles is getting higher and higher.Electronic equipment continuously generates electromagnetic signals during operation,which affects the operation of surrounding equipment,and at the same time,it will continue to be subjected to electromagnetic interference from surrounding electronic equipment.In recent years,electromagnetic compatibility laboratories for driving motor systems for electric vehicles have gradually increased,including wall-shaft type and mobile type,etc.The consistency of the test results is the focus of the industry.After electromagnetic compatibility test and analysis,the same drive motor system is tested on different loading benches for EMI test,and the test amplitude differs by 10 d B at a certain frequency.In addition,if the same drive motor system is subjected to multiple EMI tests on the same loading platform,the test results will also vary.In order to standardize the electromagnetic compatibility test bench and refine the uncertainty of the test,this paper uses the wall-through shaft anechoic chamber as the experimental condition to design a set of standard components of the drive motor system and conduct simulation analysis.According to the principle of superposition of electromagnetic signals,an anechoic chamber floor noise experiment method is proposed.The electromagnetic signal of the EMI test is subtracted from the electromagnetic signal of the floor noise test to obtain the electromagnetic signal of the driving motor system.The resulting electromagnetic compatibility evaluation result is more with accuracy.The main contents of the research are as follows:This paper analyzes the specific structure and control algorithm of the drive motor system in detail,including direct torque control,vector control,etc.,and chooses the vector control as the control algorithm for the electromagnetic compatibility experiment.The mathematical model of permanent magnet synchronous motor is analyzed,and its simulation model is built in MATLAB/Simulink environment,and the method of offline parameter identification of permanent magnet synchronous motor is studied.The vector control of permanent magnet synchronous motor is researched.The vector control is divided into three modules: coordinate transformation,space vector pulse width modulation,and PI parameter tuning.The working principle of each module is analyzed in detail,and it is built in MATLAB/Simulink environment simulation model of each module and simulation analysis.The simulation results show that the vector control current closed loop and speed closed loop with id=0 are realized,which meets the requirements of the electromagnetic compatibility experiment of the drive motor system.The experimental purpose and experimental methods of the anechoic chamber floor noise experiment are analyzed in detail,the topology circuit of the passive processing unit is designed and the simulation analysis is carried out.The simulation results show that the passive processing unit can double,rectify,filter and feed the electrical energy generated by the permanent magnet synchronous motor to the power grid,which meets the requirements of the anechoic chamber noise experiment.According to the standard parts of the drive motor system in this paper,the noise floor experiment and the electromagnetic compatibility experiment are carried out in the anechoic chamber,and the current waveform measured in the experiment is compared with the simulated waveform,which has guiding significance for analyzing the influencing factors of EMC anechoic chamber evaluation.