基于直轴电压分析的PMSM逆变器死区补偿策略

Dead Zone Compensation Strategy for Inverter of PMSM Based on Direct Axis Voltage Analysis

死区效应会导致逆变器输出电压畸变,使永磁同步电机SVPWM控制的实际输出电压不等于给定的参考电压,降低控制性能。对永磁同步电机驱动系统中的逆变器死区效应进行分析和补偿,建立包含死区的逆变器输出电压数学模型,提出一种基于直轴电压分析的死区补偿策略,通过分析电压谐波在线辨识死区大小,然后根据数学模型进行前馈电压补偿。该方法无需添加硬件,且实现简单,仿真和试验表明该方法能够有效消除死区导致的电压、电流谐波。

The dead-zone effect will lead to the output voltage distortion of the inverter,so that the actual output voltage controlled by the PMSM SVPWM will not be equal to the reference voltage,which reduces the control performance.The inverter dead-zone effect of synchronous motor drive system is analyzed,the mathematical model of the output voltage including the dead-zone effect is established,and a dead-zone compensation strategy based on direct-axis voltage analysis is proposed.The size of dead zone can be identified online by analyzing voltage harmonics,then the feed forward voltage can be compensated according to the mathematical model.This method doesn’t need additional hardware,and is simple to implement.Simulation and experiment show that the method can effectively eliminate the voltage and current harmonics caused by the dead zone.