A Novel Lifetime Prediction Method for Press Pack Devices Based on Fretting Wear

With the continuous development of the power semiconductor, the press pack devices are widely used in high-voltage and high-capacity devices owing to their simple structure and double-sided heat dissipation. Since the weak points and failure mechanisms of press pack devices are different from those of traditional soldered devices, the traditional stress-based lifetime model is no longer applicable to press pack devices. In this paper, a coupled thermo-force-wear lifetime prediction method for press pack devices is proposed by combining the failure modes and failure mechanisms of the press pack devices, and the method is used to predict the lifetime of the devices without testing, which greatly saves time and cost. The method was experimentally validated by power cycling experiments. Under different temperature stress, the experimental results differed from the simulated results by 3.04% and 2.11%, which indicated that the method could accurately predict the lifetime of the press pack device under the full temperature stress segment.