CUK converter fed resonant LLC converter based Electric Bike Fast Charger for Efficient CC/CV Charging Solution

ABSTRACT The proposed model comprises a CUK converter fed resonant LLC (Inductor Inductor Capacitor) converterbased charging solution for an e-bike battery pack, wherein the CC/CV (Constant Current/Constant Voltage) charging algorithm is implemented through the LLC converter. Heretofore, modifications were made in DCDC converter topology to incorporate bridge-less topology to increase efficiency to eliminate current inrush issues and involve galvanic isolation. Moreover, bypassing the switching losses presented by a half-bridge converter. The presented topology operates a pulse-width modulated CUK converter in DCM (discontinuous conduction mode), which serves natural current shaping without an input ripple filter. The LLC converter eliminates switching losses by undergoing ZVS (zero voltage switching) and allows high-frequency operation. The closed-loop control of the trigger pulses of the CUK and LLC converters is responsible for the CC/CV charging of the battery and hence the reduced charging time. An 800 Wh CC/CV charger with a current rating of 16 A is developed to charge a 48 V, 20 Ah Li-ion battery, where the battery is expected to charge in less than 2 hours.