The large-size low-stray-parameter planar bus bar for high power IGBT-based inverters

The large-size planar DC bus bar is widely used in high power converters, whose stray parameters are significantly affected the converter reliability and performance. Taking the example of an actual 315kW/400V inverter, the design, simulation and analysis for its bus bar stray parameters is described in detailed. Being different from the conventional method that considers the bus bar conductor as an entirety, an improved method is proposed in this paper, which separates the bus bar into several segments and evaluates the influence of stray parameters in each segment to the power semiconductor devices respectively. Therefore, this improved method can provide support for the more accurate and effective design and optimization of bus bar. In addition, two different structure of bus bar are implemented in the actual inverter, the comparison and analysis of experiment results for both structures proves the validity of the proposed method.