This thesis investigates the impact of electric vehicle (EV) charging on distribution power systems through the following two tasks. The first task is to build the model of EVs connecting to the grid. Based on this model, the impact of EV charging on the distributed system at the neighborhood level is analyzed on both summer and winter peak days. These impacts are evaluated by taking into account the limitations of the rated transformer capacity and secondary drop lead current. In addition, as a practical concern for the power grid, the transformer ageing cycle is also investigated when EVs
are penetrated into the grid. The other task is to investigate the impact of EV penetration across the entire distribution system. The EV charging impact on a feeder of the distribution system of Hydro Ottawa is assessed by considering the feeder unbalance and energy loss.