Design and optimization of laminated busbar to reduce transient voltage spike

The presence of loop inductance causes significant surge voltage due to hard-switching operation of voltage source inverters. This generally requires high-voltage rating of switching devices, which results in additional cost and power loss. This paper presents a surge voltage model to study busbar stray inductances in Electric Vehicle systems. The model demonstrates that the inductance of commutation cells contributes to significant voltage surge, resonance and electromagnetic interference. Based on modeling, the design tradeoff of different busbar structures can be analyzed by finite elements methods (FEM), which are based on Maxwell equations. The optimal design is proposed to reduce stray inductances of interconnection busbars for electric vehicle drive systems. Finally, the proposed design and optimization are evaluated by both simulation and experimental tests.