Using the Case Temperature Cooling Curves to Monitor the Thermal Impedance of IGBT Module and TIM

In this paper, we proposed a method for monitoring the thermal impedance of IGBT module and thermal interface material (TIM) using the case temperature cooling curves. Advantages of this approach include no need to measure the power loss and heat the module to thermal steady state. Experimental tests are performed to verify the effectiveness of the proposed method. Results indicate that the proposed method not only can monitor the aging process of IGBT module, but also the degradation of TIM.