A Novel Diagnosis Method for IGBT Open-Circuit of Modular Railway Power Conditioner

Modular railway power conditioner (MRPC) is excellent in high-speed railways power quality harnessed synthetically. However, the MRPC is composed of masses of sub-modules (SMs), which brings severe challenges to safe and reliable operation. In addition, since IGBT open-circuit is the most common fault, the diagnosis and location of the open-circuit fault are significant. In the steady-state operation of MRPC, the converters on both sides operate in the mutual rectification and inversion states, respectively. However, most of the existing open-circuit fault location strategies cannot satisfy the demand of two kinds of operation modes at the same time. To address this situation, a novel diagnosis method based on switching actions counting for IGBT open-circuit fault is proposed in this paper, which satisfies the fault location both in the rectification and inverter states. Finally, the effectiveness of the proposed control strategy is verified by simulation.