器件共享型三电平逆变器容错控制

Fault-tolerant control of device sharing three-level inverter

针对有源中点钳位(ANPC)型三电平逆变器现有容错拓扑难以对多桥臂多开关管复合开路故障进行有效容错、以及器件利用率较低的问题,提出了器件共享型ANPC三电平逆变器容错拓扑,对系统单管、相内双管以及相间多管等不同故障类型设计了容错拓扑重构方法,在不降低或少量降低系统输出性能的情况下实现对各类复合故障的有效容错。为解决传统离线容错控制算法对非预期故障容错能力较弱的问题,提出了一种基于组合逻辑的自适应容错控制算法,根据故障类型和故障位置在线求解并获得合适的容错拓扑重构开关驱动控制信息,生成有效的容错控制开关状态表,结合PWM容错控制算法,实现故障的实时容错控制。仿真和实验结果表明,器件共享型容错拓扑能够保证逆变器在容错运行时的输出性能,且器件利用率高,冗余成本较低。

Aiming at the problem that the existing fault-tolerant topologies of the ANPC three-level inverter have difficulty in handling multi-device fault among three phases and improving utilization rate of power device,the device sharing ANPC fault-tolerant topology was presented.The topology reconfiguration strategy was designed for different fault categories including single-device fault,double-device fault and multi-device fault among three phases,which can tolerate various complex failures without derating operation or with only a small reduction in output performance.Meanwhile,in order to solve the problem that the traditional offline fault-tolerant control algorithm has difficulty in handling unexpected faults,an adaptive fault-tolerant control algorithm based on combinatorial logic was proposed.The algorithm was designed to find the appropriate topology reconstruction scheme online based on the fault category and its position and generate the effective fault-tolerant switch state table.By combing the PWM fault-tolerant control scheme,the proposed algorithm can tolerate various switch faults in real time.Finally,both simulation results and experimental results indicate that the device sharing fault-tolerant topology maintain the output performance of the inverter in fault-tolerant operation with higher the utilization rate and lower redundancy cost.