Power distribution control strategy for cascaded multi-level dual-source traction inverter drives to enhance efficiency and dynamic response

Abstract

A control strategy for a cascaded multi-level dual-source traction inverter is proposed to boost its power capability in order to enhance its efficiency and dynamic response. It is based on a power distribution algorithm performing optimal dynamic control of power flow between dual power sources and the load, such that the primary source (battery) and secondary (ultracapacitors) work cooperatively in order to achieve maximum accelerating and regenerative braking abilities. At the same time, the proposed strategy minimizes harmonic distortion at the inverter output to enhance efficiency and performance. The viability and superior performance of the proposed control strategy are verified by extensive experimentation on a prototype of the inverter.