Current distribution in high power laminated busbars

The new LV8900 900 V variable speed drive range from Converteam utilises 3-level NPC inverter topology, featuring multi-layer laminated busbars. These laminates contribute to the commutating stray inductances, and laminate resistive losses in high current and high switching frequency applications are affected by the skin effect. This paper describes models implemented in FastHenry and Simulink accounting for these effects in the laminates as part of the design process. The results show close matching to experimentally measured laminate losses and correct prediction of stray inductance behaviour.