Research On Safety Control Strategy Of PMSM Position Detection Failure In Electric Vehicles

With the increase in the number of cars,the demand for oil is increasing,and the pollution of the car's exhaust emissions is becoming more and more serious.According to the current situation of resources and environment in China,the electric vehicle industry in our country has begun to rise gradually and become mature gradually.In the development process of electric vehicles,many problems will be encountered.The most serious problem is the safety of electric vehicles.Therefore,it is imperative to study the safety of electric vehicles.There are many reasons for the safety of electric vehicles,such as sensor failure,battery failure,etc.Sensor failures in electric vehicles are usually classified into current sensor failures and position sensor failures.The most serious safety problems are caused by position sensor failures.This topic focuses on safety problems caused by position sensor failures.In view of the failure of permanent magnet synchronous motor(PMSM)position sensor in electric vehicles,this topic has designed corresponding safety control strategies to ensure the safety of electric vehicles.The safety control strategy is mainly composed of a failure determination strategy and a failure handling strategy.In the failure determination strategy,two different methods,the angle estimation model and the Unscented Kalman Filter(UKF),are proposed to meet different requirements.A failure handling strategy based on phase-locked loop is proposed for high speed state.At low speed state,a failure handling strategy with high frequency current injection is proposed.Based on the traditional coordinate system,a new coordinate system is established to analyze the two failure handling strategies,which provides a new idea for the subsequent research.Simulation of the proposed safety control strategy proves the feasibility of the control strategy.Hardware device of the motor controller was fabricated and debugged.The safety control strategy is added to the software algorithm and tested on the dynamometer to verify the reliability of the safety control strategy.