永磁同步电机驱动系统逆变器故障诊断研究

STUDY ON FAULT DIAGNOSIS OF INVERTERS IN PMSM DRIVE SYSTEM

采用混杂系统理论的分析方法,建立更精确的电机驱动系统开关函数模型--混合逻辑动态模型。并由此提出一种基于电流残差的永磁同步电机驱动系统逆变器开路故障诊断方法。该方法利用主控制器的变量,无需额外的传感器,构造的观测器直接引入真实检测电流,避免观测误差以及时间延迟,而且逆变器发生开路故障时残差与时间成正比,时间越长,残差量就越大,且极易检测,可靠性高。这种方法摆脱了负载和主控制器的影响,具有很强的鲁棒性。反应迅速,能在故障发生的1/4周期之内完成诊断与定位。通过Matlab/Simulink仿真研究验证所提故障诊断方法的可行性和有效性。

The PMSM drive system contains the continuous state variables and the discrete variables,which is a typical hybrid system.In this paper,the hybrid system theory is introduced into the analysis process,the discrete voltage model of the inverter is embedded into the continuous state equation of the motor,and the hybrid logic dynamic model of the motor drive system is established.On this basis,a diagnosis method in permanent magnet synchronous motor drive system based on current residual is proposed.The method utilizes variables already used by the main controller,avoiding the use of extra sensors.Observation error and time delay is avoided because of the use of the real detection current.The open circuit fault residual is proportional to the time when inverter open circuit fault occur,so fault detection is very easy and reliable.This method can get rid of effects of the load and the main controller to obtain reliable detection.Fault diagnosis and location only need less than 1/4 cycle after the fault occurs.The simulation verifies its feasibility and validity of the proposed diagnostic method.