基于状态观测器的三电平逆变器故障检测与识别

Fault Detection and Identification for Three-level Inverter Based on State Observer

针对NPC三电平逆变器单相桥臂半导体器件的开路故障,在建立三电平逆变器状态空间模型的基础上,通过分析各类故障特征提出了相应的故障后逆变器状态空间模型,由此构建状态观测器,并基于此对相应的故障检测与识别算法进行研究,最终通过仿真建模对故障诊断策略的有效性进行了验证。仿真结果表明,基于状态观测器的方法可以快速检测故障发生,并能准确识别故障器件和类型,达到了预期目标。

A method of fault detection and identification based on the state space model of NPC three-level inverter is proposed for the open-circuit fault of each semiconductor component located at single phase leg. A state observer with the abilities of fault detection and identification is thus constructed to examine the proposed method by analyzing the fault characteristic of each component and corresponding state space model. A simulation is then built to verify the effectiveness of the proposed fault diagnosis method. The result shows that the state observer can detect the fault rapidly, and identify the fault type and component, the proposed method suggests a flexible and scalable solution to improving reliability in NPC three-level inverter.