NPC三电平逆变器混杂建模及开路故障诊断  

Hybrid modeling and open-circuit fault diagnosis of NPC three-level inverter

作　　者：余运俊[1] 裴石磊 谢玉麟 Yu Yunjun;Pei Shilei;Xie Yulin(School of Information Engineering,Nanchang University,Nanchang 330031,China;Nanchang Industrial Research Institute,Nanchang 330031,China)

机构地区：[1]南昌大学信息工程学院,南昌330031 [2]南昌市工业技术研究院,南昌330031

出　　处：《电测与仪表》2020年第11期16-23,共8页Electrical Measurement & Instrumentation

基　　金：国家自然科学基金资助项目(61563034);国家国际科技合作专项(2014DFG72240);江西省自然科学基金资助项目(20151BAB206051)。

摘　　要：由逆变器、滤波器、负载和控制器等组成的逆变系统可视为一个混杂系统,传统的建模方法不能有效地揭示系统的状态特性,影响逆变器功率管故障分析和诊断的准确性。文中介绍了一种基于混合逻辑动态模型的NPC三电平逆变器故障诊断方法。分析了NPC三电平逆变器的工作原理,在混杂系统理论和建模方法基础上,构造逆变系统在无故障时的状态估计器。比较功率管发生单管开路故障时逆变器输出的三相电流真实值和状态估计器输出的三相电流估计值得到残差方程,通过对残差方程表现特性进行分析实现故障诊断。设计了相应的仿真实验,实验结果表明,文中方法可以准确快速地诊断单管开路故障,验证了所述方法的可行性。The inverter system consisting of an inverter,a filter,a load,and a controller can be regarded as a hybrid system.The traditional modeling method cannot effectively reveal the state characteristics of the system,affecting the accuracy of fault analysis and diagnosis of the inverter.This paper presents a new fault diagnosis method based on mixed logic dynamic model for the open-circuit fault of neutral-point clamped(NPC)three-level inverter.Firstly,the working mechanism of the NPC three-level inverter is analyzed and the state estimator of the inverter system in the non-faulty situation is constructed by analyzing hybrid system theory and modeling methods.Then,the residual equation is obtained by comparing the true value of the three-phase current generated by the inverter with the estimator value of the three-phase current generated by the state estimator.Finally,the residual equations in different fault situations are analyzed to realize the open-circuit fault diagnosis of single-switch.In order to verify the effectiveness of the proposed method,a simulation experiment is carried out.The experimental results show that the proposed method can accurately and quickly diagnose the single-switch open-circuit fault of the inverter.

关 键 词：NPC三电平逆变器 故障诊断 混合逻辑动态模型 状态估计器 电流残差 

分 类 号：TM464[电气工程—电器]