An Improved Power Quality Charger for Electric Vehicle with Cuk PFC Converter

In this work, a two-stage charging approach with minimum cost and reduced size of magnetics is presented for the improved power quality charging of the light electric vehicles (LEVs). The charger provides low cost, safe and reliable charging solutions for LEVs. The charger provides a purely resistive profile at supply-side and implements low-frequency ripple-free charging for the battery. A Cuk converter based active power factor correction (APFC) circuit is used to improve the quality of power drawn by the charger from the supply. In addition to that, an isolated flyback converter is employed in the second stage to control the battery charging profile i.e. constant current (CC) mode and constant voltage (CV) mode charging. In order to reduce the size of magnetics and to implement the control with minimum cost and complexities, the converter is designed to operate in discontinuous conduction mode (DCM). A wide range of supply voltage is considered during design, to ensure the safe and reliable operation of the charger. A prototype at a power rating of 900 W is developed in the laboratory environment, to analyze steady-state and dynamic performances of the charger configuration and test results are provided to verify the performance of the charger configuration.