Design of a Single-Stage Transformerless Buck–Boost Inverter for Electric Vehicle Chargers

This paper details the design and implementation of a single-stage transformerless buck–boost inverter for electric vehicle (EV) chargers. Being different from conventional H-bridge inverters, the proposed inverter operates like buck–boost dc/dc converters instead of buck dc/dc converters. As a consequence, the advantages of a buck–boost dc/dc converter, i.e., the arbitrary relationships between its input voltage and output voltage, are still applicable to the proposed inverter. Specifically, it remains in normal operation even when the peak ac output voltage is higher than the dc-link voltage. Simulation results are finally presented to illustrate its effectiveness