Evaluation and Research on Vibration Fatigue Lifetime of On-board IGBT Based on Physical-statistical Model

Abstract

In the on-board environment of new energy passenger vehicles, IGBT modules are prone to the risk of vibration fatigue failure due to the influence of road roughness and engine rotation. In order to ensure the reliability of IGBT modules in service, it is of great significance to evaluate their vibration fatigue lifetime. The internal structure of IGBT module is complicated, so it is impossible to directly evaluate the vibration fatigue lifetime based on a physical model alone. To this end, an evaluation method is proposed in this paper to determine the vibration fatigue lifetime of IGBT modules. Firstly, the failure lifetime data of IGBT modules under high vibration magnitudes are obtained by an acceleration test. Secondly, the reliability lifetime distribution under the actual working conditions is obtained from the lifetime distribution statistical model based on the Weibull distribution, and then the reliability lifetime data in the practical application is obtained. The experimental results show that this method can effectively predict the failure rate of IGBT modules used in batches, which provides guarantee for reasonable management and control of application risks.

Keywords

• igbt module
• vibration fatigue lifetime
• accelerated testing
• reliability
• electric vehicle