基于开绕组电机的双三电平逆变器容错控制方法

Fault-tolerant control of dual three-level inverter for open-end winding induction motor

针对双逆变器供电拓扑在提高变频器输出电压和输出电平数的同时具有良好的容错性能这一特性,提出了一种基于参考电压矢量解耦的五电平SVPWM容错算法。该方法在简化算法的同时满足了系统容错控制要求;直接利用解耦后的三相给定相电压计算出相应的切换时刻,省略了复杂的扇区判断和查表;利用最优空间矢量位置原理对平衡控制因子进行修正,在精确控制中点电位平衡的同时,降低电压电流谐波。仿真及实验结果表明,该方法能够有效应用于故障情况,缩短程序运行时间,改善输出电流谐波特性。

Because of the higher output voltage,more output levels and better fault tolerance of dual inverter topology,an algorithm of five-level SVPWM fault-tolerant control based on the decoupled reference voltage vectors is proposed,which is simpler while meets the requirements of fault-tolerant control.The corresponding switching times are directly calculated according to the decoupled three-phase reference voltages,avoiding the complex sector judgement and table lookup.Based on the optimal space vector location theory,the neutral point potential balance is precisely controlled and the current harmonic is also reduced.Simulative and experimental results show that,the proposed algorithm can be effectively applied in faulty conditions,resulting in the reduced time of program running and the better harmonic performance of output current.