基于ESO-MLD的逆变器开路故障快速诊断方法

为了减小电机驱动系统中未知干扰对逆变器开路故障诊断的影响,提出了一种基于扩展观测器ESO(extended state observer)和混合逻辑动态MLD(mixed logic dynamic)模型的逆变器开路故障快速诊断方法。通过分析开关管在正常工作和故障状态下的电流流向路径,建立了逆变器的混合逻辑动态模型,并设计了一种电压扩展观测器。根据观测器的观测电压和实际系统输出电压之间的相电压残差进行故障检测,通过故障相残差与正常两相残差之间的数值关系来定位故障相和故障管。该方法有效减小了系统中未知干扰和不确定因素对逆变器故障诊断的影响,提高了故障诊断率。最后,通过Matlab/Simulink仿真验证了该方法的正确性和有效性。

Fast Diagnosis Method for Open-circuit Fault of Inverter Based on ESO-MLD

To reduce the influences of unknown disturbance in a motor drive system on the open-circuit fault diagnosis of inverters, a fast open-circuit fault diagnosis method for inverters based on extended state observer (ESO) and mixed logic dynamic (MLD) is proposed. The MLD model of inverters is established by analyzing the current flow path when the sw-itches work in normal and fault states. In addition, a voltage ESO is designed. The fault is detected according to the phase voltage residual between the observed voltage value of the observer and the actual voltage output from the system, and the locations of fault phase and fault switches are located according to the numerical relationship between the fault-phase and normal two-phase residuals. This method effectively reduces the influences of unknown disturbance and uncertain factors in the system on the fault diagnosis of the inverter, thus improving the fault diagnosis rate. Finally, the correctness and validity of the proposed method are verified by simulations using Matlab/Simulink.