Advanced multi-winding transformer equalizer for electric vehicle battery system

In this paper, a charge equalization converter using multi-winding transformer for electric vehicle battery system is presented, and two balancing strategies named Top-balancing and Bottom-balancing are respectively proposed. In order to properly increase the equalizing current and protect the components from excessive current as well, the way to design the MOSFET drive circuit and system duty cycle is described. To verify the usefulness of the charge equalizer design method, several examples and experimental results are shown.