Design the Phase Output Bar for Improving Static Current Sharing among Parallel IGBTs in High Power Stack Application

Abstract

In this paper, co-simulation with Q3D and Simplorer was used to design a phase output bar (POB) for achieving equal static current sharing among three parallel IGBTs in single-phase power stack. Hence the current derating could be reduced, and current utilization will be increased in the parallel IGBTs. Q3D was adopted to design the stray inductance of the POB used to connect the phase terminal of IGBT modules to load, for attaining maximum ratio of imbalanced current (MRIC) of the three IGBT modules is within 3% under 200% rated current (2400A/per IGBT module), and the stray inductance of the POB was verified by the constant-current-slope method. The performance of the current sharing with designed POB was verified using a double-pulse test (DPT) in the power stack. Finally, a power stack with DC link voltage of 1000V based on three parallel half-bridges was constructed. The co-simulation and experimental results indicated that the MRIC of the proposed design power stack were 0.8% and 0.9%, respectively, the effectiveness of the proposed design for the POB was shown.