Improvement for planar bus bars of high power inverters based on segmented evaluation of stray parameters

The stray parameters of large-size planar DC bus bar are significantly affected switching behavior of power semiconductor devices in high power inverters. The method of segmented evaluation of stray parameters is different from the conventional one, which separates the bus bar into several segments according to the configuration of DC-link capacitors and evaluates the influence of stray parameters in each segment to the power semiconductor devices respectively, instead of considering the bus bar conductor as an entirety. Based on the quantitative evaluation factors, a more effective improvement of bus bars is described in this paper. Besides the improved one, two typical structures of planar bus bars are implemented, tested and compared under high power conditions with the same configuration of DC-link capacitors and the same IGBT devices. The experimental results proves the validity of the improvement based on the method of segmented evaluation of stray parameters.