An Isolated Bridgeless Cuk-SEPIC Converter-Fed Electric Vehicle Charger

A single-stage electric vehicle (EV) battery charger with an isolated bridgeless (BL) Cuk-single-ended primary-inductor converter (SEPIC) converter is developed in this article. The design of proposed charger is ensured in discontinuous conduction mode with intrinsic power factor correction (PFC) at ac mains. Compared to the BL Cuk converter topology when used for both positive and negative cycles, the proposed topology has reduced number of components with improved efficiency. This is due to integration of Cuk and SEPIC converters during the individual half cycle. The presence of output inductor at Cuk converter side also smoothens the output current, as compared to SEPIC converter used for both cycles. A high power quality (PQ) operation of new BL isolated PFC converter with an EV battery load of 48 V/100 Ah is verified using single-phase PQ analyzer. A laboratory prototype of proposed charger is developed and validated to corroborate the efficient performance during two charging profiles. Test results are shown under steady state as well as over extreme load and line conditions. Different performance indices such as displacement PF, ac mains PF, and mains current distortion are recorded, which comply the IEC 61000-3-2 standard.

Automated summary

This article presents the development of a single-stage electric vehicle (EV) battery charger using an isolated bridgeless Cuk-single-ended primary-inductor converter (SEPIC) converter. The proposed charger design ensures intrinsic power factor correction (PFC) at AC mains and offers improved efficiency compared to the traditional BL Cuk converter topology. The performance of the charger with a 48V/100Ah EV battery load is validated using a single-phase PQ analyzer.