Battery ripple effects in cascaded and parallel connected converters

Abstract

The area of interest in this study is the current ripple the battery sees as part of the EV drive train. Current research is focussing on using converters in different topologies to reduce the battery peak demand to reduce rate capacity effect. This study describes the effects the choice of topology can have on the battery current ripple. Any ripple as seen by the battery increases losses and temperature which results in a reduced capacity and battery life span. Therefore it is important to be able to control the size of the ripple and its frequency. The research presented in this study analyses two topologies popular in EV drive trains and shows a clear advantage in terms of battery current ripple reduction of parallel topology over the cascaded topology. The method of simulation, the simulation results and the conclusions are presented and discussed in this study.