A Power-Factor-Corrected LLC Resonant Converter for Electric Vehicle Charger Using Cuk Converter

This article presents an improved power quality Cuk-converter-fed isolated
LLC
resonant converter for an electric vehicle battery charger (EVBC), intended typically to charge a small two- or three-wheel-driven electric vehicle (EV) using up to 20-Ah battery. The proposed topology consists of two converters, comprising of the first stage for power factor correction (PFC) and the second stage for effective charging of the EV battery using a constant-voltage and constant-current mode control algorithm. In the first stage, the Cuk converter performs PFC by operating in the continuous conduction mode of the primary inductor, while the
LLC
resonant converter converts the dc-link voltage to the isolated dc voltage required for the EVBC. The proposed converter uses a frequency control algorithm to actively vary the intermediate dc-link voltage based on the state of charge of the battery leading to reduced turn-
off
losses in the
LLC
converter switching devices. The proposed converter is designed and simulated in MATLAB. Simulated results are analyzed and discussed in detail. Finally, a 580-W 10-A experimental prototype of the EVBC is developed, and test results are presented to demonstrate the effectiveness of the proposed topology. The proposed converter exhibits excellent power quality indices adhering to the IEC-61000-3-2 international standard.