A Bidirectional Onboard Charging System for E-Rickshaw Using Interleaved SEPIC Converter

This work proposes a bidirectional power flow topology for an onboard charger (OBC) of an e-rickshaw. The grid connected OBC is designed, modeled and its performances is studied in detail. This topology has two stages interconnected with the DC link capacitor. Its first stage is a front-end converter. It regulates the voltage at the DC link capacitor and regulates the power quality within the IEC 61000-3-2 standard. Its second stage is DC-DC converter. It regulates the output charging current. Moreover, the bidirectional power flow operation is demonstrated in detail. The vehicle to grid (V2G) operation is regulated by the second stage DC/DC converter. The bidirectional interleaved isolated SEPIC (ii-SEPIC) converter topology is used for OBC. A multistep constant current charging scheme is selected for the operation of the OBC. A 2kW bidirectional OBC is designed. PI controllers and the pulse width modulation switching are designed for both the stages.