Influence of open-switch failures on DC-link capacitors in hybrid ANPC inverters.

This paper analyzes the influence of a DC-link capacitor under open-switch failures in hybrid active neutral point clamped (ANPC) inverters that consist of Si-IGBTs and SiC-MOSFETs. Open-switch failures cause the current harmonic distortion of DC-link capacitors. This distorted current affects the capacitor loss increase, which in turn affects the lifetime decrement of the DC-link capacitor. These influences of open-switch failures on inverter operation have not been discussed despite the fact that they lead to secondary failures of the system. In this paper, the influence of open-switch failure is analyzed based on the current harmonics of the DC-link capacitor, which experiences the highest failure rate. Simulation and experimental results demonstrate the effects of various open-switch failure scenarios on DC-link capacitors in terms of current harmonics and lifetime. [ABSTRACT FROM AUTHOR]