Study on planar busbar regarding stray inductance minimization and oscillation suppression for high power converter

Planar busbars have played a significant role in reducing the parasitic/stray inductance in modern high power converters, which is caused by physical current path loop from the IGBT to DC capacitors. Consequently, it may lead to such problems as non-ideal converter operation, over-voltages, voltage drop, current unbalance and resonance with DC capacitors as well as snubber capacitors, especially applied with active power filters (APF) usually with a wide range of current frequency. This paper presents a new physical structure for a voltage source inverter applied in 380V/400A APF with low inductance and oscillation busbar structure, in which the design considerations and analysis are given. The experimental and simulation results show that it obtained very low stray inductance and had good electromagnetic compatibility (EMC) performance.