I. Introduction
THE failure mechanisms of power devices are mostly associated with the junction temperature swing and the high average junction temperature [1]. The former plays a more important role in the wear-out failures due to the nonconstant thermal expansion coefficients between different material layers, and the latter is more likely to cause catastrophic damage to the power device during transient or short-term operation [2], [3], especially when the ambient temperature of the working environment is very high, such as EVs [4]. For a given DAB converter, the reliability is usually limited by the most stressed power semiconductor device with the highest average junction temperature. One usual way to manage the thermal distribution is employing active thermal control methods [5], which are mostly obtained by means of rearranging the power losses distribution [6].