Influence of inverter DC voltage on the reliability of IGBT

LESIT and thermal models are proposed to calculate the reliability of IGBT modules in order to solve the problems of low reliability of power devices in an inverter. The relationship between DC voltage and power losses is analyzed, and a new method to improve the reliability of IGBT modules is obtained. It is shown that when the switching frequency does not changed, a suitable DC voltage exists to satisfy a high reliability for an inverter. Meanwhile, when the DC voltage could not change, the switching frequency can be adjusted to improve a high reliability. In this paper, we show that the higher the switching frequency is, the lower the DC voltage is, which can lead to a higher reliability of IGBT modules.