基于直接转矩控制技术的异步电机驱动系统两种容错方案研究

Two Tolerant Schemes for Induction Machine Drive System Based on DTC Strategy

对采用直接转矩控制技术的异步电机驱动系统进行了两种容错方案研究。对功率开关无驱动故障容错后 ,方案 1系统重构为四开关两相运行系统 ,方案 2系统重构为四开关三相运行系统。研究了四开关系统中磁链和转矩的观测方法 ,分析了仅有的 4个有效电压矢量对磁链和转矩变化所产生的影响 ,提出了四开关系统直接转矩控制中磁链和转矩的控制方案。对两种容错方案的特点进行了分析比较。仿真与实验结果证明了两种容错方案的有效性。

Two tolerant schemes for the induction machine drive s ys tem with a direct torque control (DTC) technique are investigated. After the mis firing fault on one of the power switches is detected and the fault inverter leg is isolated, the drive system is reconfigurated as a four-switch two-phase o perating system in the first scheme, and a four-switch three-phase operating s ystem in the second scheme. Observe methods of flux linkage and torque in four- switch systems are studied. Influence of the four active voltage vectors on flux linkage and torque variation is analyzed. Control schemes for the flux linkage and torque in DTC of four-switch systems are proposed. Features of two tolerant schemes are analyzed and compared. Simulation and experimental results verify t he validity of two tolerant schemes.