Coordinated electric vehicle charging strategy for optimal operation of distribution network

Because of global warming and shortage of fossil fuels, much attention has been paid to plug-in electric vehicles (PEVs) worldwide in recent years. With possibly millions of PEVs on road in the future, it is essential for power network operators, especially distribution network operators, to implement coordinated PEV charging. In this paper, an optimal charging method is proposed for PEVs to maximize profits of distribution companies. By introducing voltage constraints, the optimization method guarantees both security and economics of distribution network operation. To reduce computational difficulties, an iterative approach is presented and linear programming models are built and solved in each iteration with updated nodal voltages. The computing speed of the method can meet the need of real-time operation. Using the 12.66kV, 33-bus distribution network as the test system, simulation results show merits of the coordinated charging method and effectiveness of the proposed voltage constraints.