Optimal control of on-board PEV chargers considering distribution line capacity and building load imbalance

This paper presents an optimal charging method for plug-in electric vehicles (PEVs) with single-phase on-board chargers that are connected to a large apartment buildings. The objective of the optimal charging is to minimize the total line power loss in a distribution network while taking into account the distribution line capacity and the three-phase building load imbalance. Using the inherent capability of the associated power electronics, the single-phase PEV chargers operating within capacity limits provide reactive power to minimize the power loss. The single-phase charging power is also controlled differently in time to mitigate the three-phase building load imbalance. For the active and reactive power control of the PEV charges, an optimization problem is formulated and solved using a linear programming algorithm with a substantial reduction in the simulation time. Based on a theoretical analysis performed on a simple distribution network, simulation case studies compare the conventional and proposed PEV control methods, to demonstrate that the objectives can be effectively achieved under various grid conditions.