New topology for management of bi-directional power flow between vehicle and grid with reduced ripple current at unity power factor

Abstract

In this paper, a new topology of single-phase pulse width modulated (PWM) AC-DC converter is proposed for bidirectional power flow between plug-in hybrid electric vehicle (PHEV) and the grid. This converter consists of a PWM voltage source converter (VSC) and a ripple reduction circuit. The ripple reduction circuit consists of a switching leg and an inductor. The inductor is connected between the midpoints of the second and third legs of VSC. An AC voltage of 230 V, 50 Hz is converted into 400 V DC using a single-phase VSC with ripple compensation circuit. A buck-boost DC-DC converter charges and discharges the battery of the electric vehicle (EV) or PHEV with this 400 V DC. While in discharging mode, it feeds energy back to the grid. The zero voltage regulation (ZVR) and power factor correction (PFC) modes of operation at PCC are also achieved with reactive power compensation and harmonics elimination of other connected loads at PCC with modified control in order to improve the power quality at the grid.