考虑电压电流约束的感应电机容错运行对比研究

Comparative Study on Fault-tolerant Operation of Induction Motor Considering Voltage and Current Constraints

围绕电机驱动系统可靠性提高问题,对现有几种具备容错运行能力的三相感应电机驱动系统性能开展了对比研究。对容错控制策略的评估应考虑电机驱动系统输出的实际转矩和转速,而这主要取决于系统电流和电压约束。考虑到励磁电流的存在,感应电机驱动系统中的电流极限不如永磁电机驱动系统中的电流极限直观,同时逆变器和电机都存在对系统电压的限制,故通过推导故障后电机驱动系统的电压方程,分析得到了电机参数、运行工作点和电压电流约束对输出转速的影响,并指出优化拓扑可使故障后电机运行在额定转速以上以获得额外的功率。利用搭建的感应电机驱动测试平台开展了实验研究,不同容错策略的对比实验结果验证了理论分析。

Focusing on the problem of improving the reliability of motor drive systems,a comparative study on the performance of several three-phase induction motor drive systems with fault-tolerant operation capabilities was carried out.The evaluation on the fault-tolerant control strategy should consider the actual output torque and rotation speed of the motor drive system,which mainly depends on the system current and voltage constraints.Considering the existence of excitation current,the current limit in the induction motor drive system is not as intuitive as that in the permanent magnet motor drive system.At the same time,both the inverter and motor have constraints on the system voltage,so the effects of motor parameters,operating points and voltage and current constraints on the output speed are analyzed by deducing the voltage equation for the postfault motor drive system.In addition,it is pointed out that the optimized topology can make the postfault motor run at a rotation speed higher than the rated speed to gain extra power.An experimental study was carried out on an induction motor driving test platform,and the comparative experimental results under different fault-tolerant strategies verified the theoretical analysis.