A Single Stage 1.65kW AC-DC LLC Converter with Power Factor Correction (PFC) for On-Board Charger (OBC) Application

A single stage 1.65kW AC-DC LLC converter with Power Factor Correction (PFC) for OBC application is proposed. A boost inductor is not required since the LLC converter serves as both the AC-DC and DC-DC stage which provides all the functions of rectification, PFC, output voltage regulation and galvanic isolation. A design methodology is proposed in this paper to maintain the output voltage regulation and PFC over the entire AC input voltage range from zero to peak voltage. Benefiting from the true-single-stage structure, the quantity of active switches and magnetic components is reduced. Therefore, high power density and high efficiency can be achieved with an overall reduction in the number of components. An experimental prototype is designed based on the LLC PFC design methodology. Stable DC output voltage regulation is implemented with over 99% Power Factor. Experimental testing is conducted which achieves over 2.9kW/L power density and 96.9% overall efficiency.