Fault diagnosis for indirect matrix converter based on mixed logical dynamical model

This paper proposes a fault diagnosis method based on the mixed logic dynamic (MLD) model for the indirect matrix converter (IMC), which can improve the real-time and accuracy of fault diagnosis. Firstly, the MLD model of IMC is built, and the state residual equation is constructed. Then, the characteristics of the state residuals and the variation trend of the DC bus voltage when the IMC power switch fails are analyzed in detail. Based on the above, the corresponding relationship between the inverter fault switch and the state residual was established. Combined with the characteristics of space vector modulation strategy, the trend percentage function was defined to determine the matching DC bus voltage variation trend in different rectifier sections. By detecting the change of the state residual and the trend percentage function, fault detection and localization can be realized. Finally, the simulation and experimental results verify the feasibility and effectiveness of the proposed method.