Optimization of Laminated Busbar for Three-Level NPC Topology Using SiC Module

Abstract

In high power applications, laminated busbar has been used as main connection to reduce the loop stray inductance. Nowadays, the introduction of SiC device brings more strict requirements on busbar design because of its higher switching speed. This paper presents an optimization of busbar for three-level NPC topology using 62mm package SiC module by analyzing two possible distributions of loop inductance, comparing their corresponding busbars in terms of self inductance and coupling coefficient, and optimizing capacitors' position. The inductance of the maximum current loop of the optimized busbar is 21.187nH. Furthermore, a lab prototype and a field coupling simulation are done to evaluate its feasibility.