Study on Improving the Short-Time Overcurrent Capability of Press- pack IGBTs Using Phase Change Materials

The power density of power electronic devices is getting higher and higher, and the requirements for cooling technology are getting higher and higher. Generally, the cooling configuration of the device can only meet the needs of normal operation of the device, so the power surge handing capability of devices is weak. In order to solve this problem, some scholars have proposed to use a larger heat sink or increase the cooling power. However, due to the thermal resistance between the heat source and the heat sink, the chip temperature may have exceeded the maximum junction temperature before the heat transfers to the heat sink. Therefore, this paper proposes to integrate the phase change materials (PCMs) into the molybdenum plate of the press- pack IGBT to improve its ability to resist power surge. Phase change materials do not undergo phase change when the device is operating normally. During power surge, PCM absorbs a large amount of heat for phase change while the temperature remains constant. In addition, the temperature of the molybdenum plate and the PCM can be prevented from increasing, which is beneficial to the heat conduction from the chip to the outside. Furthermore, the maximum temperature of the chip is reduced to ensure that IGBT can work normally during power surge. In this paper, the finite element simulation software COMSOL multiphysics is used to verify the simulation. The simulation results show that the overload capacity of the crimped IGBT device integrated with phase change material is significantly improved.