非线性负载下的三相逆变器开路和电流传感器同时故障的诊断  

Simultaneous fault diagnosis of three-phase inverter open-circuits and current sensors under nonlinear load

作　　者：孙源 陈杰[1] 卫梦龙 邱瑞昌[1] Sun Yuan;Chen Jie;Wei Menglong;Qiu Ruichang(School of Electrical Engineering,Beijing Jiaotong University,Beijing 100044,China)

机构地区：[1]北京交通大学电气工程学院,北京100044

出　　处：《仪器仪表学报》2024年第11期52-64,共13页Chinese Journal of Scientific Instrument

基　　金：中央高校基本科研业务费专项资金(2023JBZY041)资助项目。

摘　　要：目前三相逆变器故障诊断的负载类型多是线性负载,随着非线性负载越来越广泛的应用,原有的方法难以解决故障时由非线性负载引起的谐波问题。此外,现有的故障诊断方法多是针对开关管或者传感器的,没有综合考虑上述故障。为了解决上述问题,提出了一种带非线性负载的两电平三相逆变器开路故障和电流传感器故障同时诊断方法。建立了逆变器三相电流状态空间方程并推导了实际占空比函数,用连续占空比函数代替离散开关函数,使状态空间方程满足观测要求。设计了基于复合控制的离散滑模观测器,复合控制采用了零相移重复控制和比例积分控制串联的结构,可以对谐波电流进行有效跟踪。设计了可调节因子检测变量和自适应阈值,通过调整调节因子可以实现快速准确的故障诊断。搭建实验台并通过实验验证了开路故障诊断时间小于3 ms,传感器故障诊断时间小于6 ms。所提故障诊断方法可以在非线性负载下实现开路故障和传感器故障的同时快速诊断。Currently,the load types for fault diagnosis of three-phase inverters are mostly linear loads,and as nonlinear loads are more and more widely used,the original methods are difficult to solve the harmonic problems caused by nonlinear loads during faults.In addition,the existing fault diagnosis methods are mostly for switches or sensors,without comprehensive consideration of the above faults.To solve the above problems,a simultaneous diagnostic method for open-circuit faults and current sensor faults in two-level three-phase inverters with nonlinear loads is proposed in this paper.The inverter three-phase current state-space equation is established and the actual duty cycle function is derived,and the continuous duty cycle function is used instead of the discrete switching function,so that the state-space equation meets the observation requirements.A discrete sliding mode observer based on composite control is designed.The composite control adopts the structure of zero-phase-shift repetitive control and proportional integral control in series,which can effectively track the harmonic current.Adjustable factor detection variables and adaptive thresholds are designed,and fast and accurate fault diagnosis can be realized by adjusting the adjustment factors.A test bench is built and experimentally verified that the diagnosis time for open-circuit faults is less than 3 ms,and the diagnosis time for sensor faults is less than 6 ms.The proposed fault diagnosis method can realize fast diagnosis of both open-circuit faults and sensor faults under nonlinear loads.Currently,the types for fault diagnosis of three-phase inverters are mostly linear loads.As nonlinear loads are more and more widely used,the original methods make it difficult to solve the harmonic problems caused by nonlinear loads during faults.In addition,the existing fault diagnosis methods are mostly for switches or sensors,without comprehensive consideration of the above faults.To address the aforementioned problems,a simultaneous diagnostic method for open-ci

关 键 词：复合控制滑模观测器 开路故障 电流传感器故障 非线性负载 故障诊断 

分 类 号：TM464[电气工程—电器] TH7[机械工程—仪器科学与技术]