30 kW Three-Phase T-Type Active Front End 3D Electro-thermal Design

In this paper, a 30 kW three-phase T-type active front end (AFE) topology is presented and the effect of layout on the parasitic inductance and thermal performance is assessed for modular off-board charging systems. According to the operation time, a mean time between failure (MTBF) is calculated for the variation of junction temperature. According to the analysis the peak junction temperature is calculated as 80 degrees C. In order to find a compromise between cooling and layout, a parametric study is performed in ANSYS Q3D for 3 different layouts with different semiconductor distances. The cooling system is then designed and several analyses are performed to achieve the layout with minimal parasitic inductance while satisfying the system lifetime key performance indicator. Finally, the layout Case2A with 10mm semiconductor separation is selected as the optimal design. The parasitic loops are calculated as 33.9 nH and 43.7 nH for the upper and lower loop, respectively. The peak junction temperature is calculated as 76.7 degrees C which is slightly below the thermal limit.