PFC‐SEPIC converter‐fed half‐bridge LLC resonant converter for e‐bike charging applications

Abstract

In today's market, electric bikes (e-bikes) are becoming exceedingly popular due to their smaller size, ease of domestic charging and cost-friendly alternative in the category of electric vehicles. So, there is a need for the development of a power factor corrected (PFC) private off-board charger (OBC) to cater to the need of the domestic charging of e-bikes. Traditionally, e-bike chargers powered by a domestic meter are realised by a non-PFC OBC with a power rating of 500-700 W. Such converters draw harmonic currents at very high crest factor and affect the life and performance of other domestic appliances. A private OBC which derives its power from the domestic supply for charging the battery of an e-bike is proposed. The charger has two stages, i.e. the PFC stage for input current shaping and the DC-DC stage for regulating the battery charging voltage and charging current. The PFC stage is based on the single-ended primary inductance converter and the DC-DC stage is based on the inductor inductor capacitor (LLC) resonant converter. A 570 W, 57.6V, 10 A prototype is built using digital signal processor (TMS320F28035) to evaluate and validate its performance for charging a lithium-ion battery pack.

Development of a three‐phase interleaved converter based on SEPIC DC–DC converter operating in discontinuous conduction mode for ultra‐fast electric vehicle charging stations

“…Although these converters experience a simpler control algorithm, they suffer from high current stresses [29]. In [30], a SEPIC-based PFC rectifier is used to feed a half-bridge LLC resonant filter for e-bike charging. This topology is suitable for low powers, and it employs a large number of components.…”

“…Unlike the studies provided in [21–31], the concept of interleaving in phase‐modular PFC rectifiers is not reported. In this regard, this paper presents a three‐phase unidirectional EV UFC designed to operate in DCM.…”

High performance single stage power factor correction circuit

“…Therefore, another converter is used after PFC stage to regulate the final output voltage. This structure is known as two‐stage structure, which is not optimal and cost effective for low power applications [3, 4]. Thus, for low power applications, typically, these two stages are merged together to use only one switch.…”