三相逆变器低成本容错拓扑的工程运行研究

针对工程运行中大功率三相逆变器功率开关器件易于损坏并造成严重事故的问题,提出了改进容错方案.首先从逆变器主电路的硬件拓扑结构入手,采用低成本电力接触器实现了事故发生时,备份桥臂与相应的触发控制线路一次性切换替代事故桥臂;再从电动机气隙磁链轨迹的控制理论出发,研究利用三相四开关逆变器拓扑结构,实现电动机准两相容错运行;最后,探讨了电动机不得不单相或准单相运行时,如何控制气隙磁链轨迹改进电动机的故障运行质量.

Research on the Topology to Low Cost Tolerant Type Three-Phase Inverter in Engineering

Improvement on fault tolerant techniques of inverter in three-phase variable frequency drive system is proposed,as inverter power devices are easily damaged and serious accident is caused.First,from the hardware topology of the inverter main circuit,backup bridge arm with the corresponding trigger con- trol circuit can switching off the accident bridge arm one-time by the low-cost electricity contactor when the accident oc- curred.Then on the ground of air-gap flux trajectory of the mo- tor control theory,the quasi-two-phases fault tolerant running of the motor is realized through the three-phase four-switching inverter topology.Finally,how to use air-gap flux trajectory control theory to improve the running quality in accident are discussed when the motor is working in single-phase or quasi- single-phase state.