Open Circuit Fault Diagnosis Of PMSM Drive System Considering Model Predictive Control

Permanent magnet synchronous motor(PMSM)has excellent characteristics such as high power density,high torque density and high efficiency.With the improvement of the performance of rare earth permanent magnet materials,the reduction of cost and the rapid development of power electronics PMSM has received extensive attention in the fields of electric vehicles,wind power generation,rail transit and other fields.However,the working environment of PMSM is relatively harsh,such as high temperature and humidity,which often leads to PMSM failure.The open circuit fault of the drive system is a common fault in the PMSM drive system.If this type of fault cannot be detected in time,it may cause a secondary failure of the motor system and even lead to greater economic losses.Therefore,it is of great scientific significance and economic benefit to conduct fault diagnosis research on PMSM drive system.Although the traditional open-circuit fault diagnosis method of the motor drive system is relatively mature,it requires high equipment installation and complex system,which leads to increased costs.Therefore,it is of great significance to study a new,easy-to-operate,cost-saving method for open-circuit fault diagnosis of motor drive systems.In recent years,model predictive control technology has been widely used in the field of motor drive and control due to its simple structure and excellent dynamic performance.Model predictive control is a control algorithm that predicts the future state of the system based on the current state of the system and the mathematical model,and then performs online optimization based on the expected value.At this stage,a lot of research has been conducted on fault diagnosis of PMSM systems based on conventional control(such as vector control,direct torque control,etc.).However,there is not enough attention and research on open circuit fault diagnosis of PMSM drive system based on model predictive control.So that,this subject proposes a PMSM drive system open-circuit fault diagnosis method based on model predictive control.This method is based on the PMSM model predictive control system unique value function feature quantity,using spatial modulation profile technology to create a value function table,by comparing the magnitude of the value functionand the threshold value stored in the table in the case of a fault,thus quickly Realize open circuit fault diagnosis of PMSM drive system.The main research contents of this topic are as follows:(1)Briefly explain the structure,working principle and mathematical model of PMSM,on this basis study the principle of model predictive current control,and build a simulation model of PMSM system based on model predictive current control under Matlab / Simulink environment.(2)Investigate the types,mechanisms and effects of open-circuit faults on motor stator current,voltage,speed,torque and other signals.(3)Under the model predictive current control mode,the influence law of open circuit fault on the value function is studied,and the value function is used for open circuit fault diagnosis.Build a simulation model to verify the effectiveness of this diagnostic method.(4)A PMSM drive system experiment platform is built to further verify the proposed fault diagnosis method.