Prediction and analysis of IGBT life of power device under multi-field load

Regarding the heat dissipation problem of the fatigue life of IGBT module under thermal vibration coupling load, the finite element analysis method and incremental damage superposition method are used to simulate and calculated the working condition of IGBT module under thermal vibration coupling effect. According to the IGBT model, the thermal cycle load was applied to the model, and the fatigue damage factor of the module under the thermal cycle load is obtained by using the modified Coffin-Manson equation. Then, the modal analysis of the module under the influence of thermal stress was carried out, and the random vibration excitation signal was applied. The damage factor of the module under the random vibration load was calculated by strain-based Coffin - Manson equation and Miners linear cumulative damage theory. A fatigue life of 59.5h was obtained through calculating the total damage value of IGBT module under thermal vibration coupling load by superposition of thermal cycle fatigue damage factor and average fatigue damage factor under random vibration. This paper can theoretically guide reliability prediction of electronic devices and the fatigue life prediction under thermal-vibration coupling load.