Control of vehicle-to-home operation of electric vehicle with seamless transition capabilities

This work demonstrates the vehicle-to-home (V2H) capability of a bi-directional electrical vehicle (EV) charger. This proposed intelligent EV charger detects the grid outage, isolates a home load from the grid, works in the V2H mode, detects the grid recovery, synchronizes and re-establishes connection to the grid, without load power interruptions. Its control is designed to have smooth and seamless transition among different modes of operation. However, to address the realistic conditions, the charger performance and its synchronizing capability are tested under grid abnormalities such as voltage fluctuations, voltage distortion both at linear and nonlinear loads. Additionally, the system operates at unity power factor (UPF) and makes the grid current sinusoidal even when the grid voltage is distorted. The second order generalized integrator (SOGI) based phase locked loop (PLL) is used to estimate the phase angle of grid voltage and point of common interconnection (PCI) voltage, and it offers the added advantage of fast dynamic response and reduced computational burden. The charger is designed to operate with a single phase, 230V, 50 Hz AC mains installation. The performance under grid disturbances and various loading conditions validate the design and control of proposed charger.