An Open-Circuit Fault Diagnosis Method Based on Horizon-Adaptive Period Correction for Voltage Source Inverter in Motor Drive

In this article, an insulated gate bipolar transistor (IGBT) open-circuit (OC) fault diagnosis method based on horizonadaptive period correction (HaPC) is proposed for voltage source inverter (VSI). It can achieve the diagnosis and location of any IGBT OC fault under frequency variation conditions. First, a horizon-adaptive period extraction (HaPE) method is proposed, which is used to accurately obtain the period of the current signal as the frequency changes. HaPE converts the signal from the time domain to the phase domain to indirectly obtain the period of the current signal, while making the number of sampling points in each period the same. Second, a multidimensional characteristic extraction based on virtual time domain period correction (VTDPC) method is proposed. It can achieve the identity of different period characteristics, thereby greatly reducing the amount of training data. Finally, support vector machine (SVM) algorithm is used for classification to locate faults. Compared with other fault diagnosis algorithms, the proposed method is not affected by the amplitude and period changes caused by frequency changes, and can accurately locate faults. Simulation and experiments verify the accuracy and effectiveness of the proposed fault diagnosis method in VSI OC fault diagnosis.