Open Switch Fault diagnosis in Three Phase Voltage Source Inverter

Abstract

At present, condition monitoring with fault diagnostics in the three-phase voltage-source inverter method is previously regarded as necessary to develop effectiveness in repairing as well as improve consistency levels. This paper illustrates a new open-circuit fault diagnosis of switching devices in the three phases Voltage Source Inverter by sensing phase currents. First, three phases current is filtered using a low pass filter which is already sensed for internal control of Voltage Source Inverter. A discrete wavelet transform is used to analyze current signals at different levels of decomposition in both time and frequency domains. Different mother wavelets are available in discrete wavelet transform which shows different results of the analysis for the same signals. The selection of mother wavelet is a crucial task which is carried out by analyzing of non-stationary current signal with different mother wavelets. Second, the effective features are selected to train Artificial Neural Network. The results show that the proposed method is effective for open-circuit fault diagnosis of switching devices fault diagnosis.