Power module with large short-term current capability by using phase change material.

There has been the desire for power electronic converters, which integrate renewable generation to the grid, to provide short-circuit (SC) current for a few seconds to drive relay protection and/or support voltage recovery following fault clearance. This has not been possible for the demanded current is significantly greater than the rating. Without proper thermal management, the junction temperature will rise quickly, resulting in thermal breakdown. In this article, a power module with extended safe operating area (SOA) is proposed and optimized to provide SC current. The proposed power module takes advantage of the heat absorption ability of phase change material (PCM) to constrain the junction temperature from rising quickly. To avoid unacceptably reducing thermal conduction, the PCM is combined with a metal framework. Thermal models are proposed to analyse the transient response and optimise the design. The phase change effect of the PCM is verified through simulation and experiment. It is demonstrated that when the junction temperature of the device is controlled below the limit, the SOA can be extended. Optimization of power module design is carried out in a particular case study in which simulation results are used to show the practicability and possibility of using the proposed concept. [ABSTRACT FROM AUTHOR]