Research on Equalization Technology of Power Pack with Improved Buck-Boost Topology

Abstract

Aiming at the problems of traditional active equalization circuit, such as long equalization time, slow equalization speed and low control precision, this paper proposes an improved Buck-Boost topology equalization circuit based on the traditional Buck-Boost topology. Layering the battery cells in series to achieve direct equalization between non-adjacent cells, improve equalization speed, and shorten equalization time. At the same time, the fuzzy controller is designed to control the equalization current through the on and off of the MOSFET, thereby further improving the accuracy of the equalization control. The simulation results show that the improved topology and the design of the fuzzy controller make the equalization time shorten by about 40% compared with the traditional structure, and the SOC curve fitting and distribution after the equalization are relatively concentrated to achieve the expected equalization effect. Keywords-Equalization Circuit; Buck-boost Topology; State of Charge; Fuzzy Control; Equilibrium Accuracy