An effective power quality battery charger using modified high gain buck- boost converter

This paper presents an efficient two-stage AC-DC active power factor corrected (APFC) high-gain buck-boost converter-based battery charger for low-voltage electric vehicles. The initial stage of this charger utilizes high-gain buck-boost converter with single switch and fewer passive components, and it performs at a lower duty cycle to reduce conduction loss and to enhance efficiency. In the second stage, flyback converter is used to provide isolation between the battery and the power circuit, in addition to regulate the battery current during the constant current and constant voltage mode. The control algorithm (APFC) of the charger is implemented in Texas Instruments C2000-based microcontroller through an auto-code generation tool software named Code Composer Studio in a MATLAB/Simulink environment which leads to reduced control complexity. Furthermore, a prototype has been constructed and tested to verify that the proposed charger compliance with IEC 61000–3–2 standards for charging a 48 V, 80 Ah lithium-ion battery under AC input voltage transients. Maximum efficiency of 95.12 % and input current total harmonic distortion (THD) of 1.8 % have been obtained from the constructed prototype. The charger's performance is satisfactory in all circumstances.