基于模糊控制零电流钳位逆变器死区补偿

摘要

Inverter dead time can cause many negative effects to ac servo system,such as waveform distortion,increased torque ripples,excessive heating of the motor.Especially,the zero current clamping of output current around zero is the serious problems at low frequency outputs.A new dead time delay compensation algorithm is proposed which can give more accurate zero current information and it can calculate error voltage caused by inverter dead time in the real time and compensation in the feedforward manner.By applying this method to SVPWM inverter system,a more accurate output voltage compensation can be achieved.At the same time zero current clamping phenomenon can be avoided efficiently,The current ripple when the system works at the low frequency is reduced.Simulation and experimental results demonstrate the proposed algorithm is effective and feasible.%逆变器死区对于交流伺服系统产生很多不利的影响,如逆变器输出电压的畸变,电动机转矩的脉动和过热等,特别是逆变器低频输出时的零电流钳位将导致系统的不稳定。本文提出了一种新型模糊补偿算法,该算法能够提供精确的零电流信息,可以实时计算逆变器死区导致的误差电压,并通过前馈方式对误差电压进行补偿。该方法应用于SVPWM逆变器系统可以达到精确的输出电压补偿,并且可有效地消除零电流钳位现象,降低系统在低频时输出电流的脉动。仿真与实验表明该算法有效、可行。