Multi-objective Optimization Strategy for Intelligent Charging and Discharging Station of Electric Vehicles in the Distribution Network

The safe operation of power grid is negatively affected by disorderly charging of electric vehicles (EVs), and the operating cost of the EVs’ charging station is also increased by disorderly charging. To solve this problem, this paper proposes a multi-objective optimization strategy for intelligent charging and discharging station (ICDS) of EVs in the distribution network, which considers the load/energy storage characteristics of EVs. An optimization model including ICDS, distribution network and distributed generation (DG) is proposed, and grid power flow of the distribution network is considered as the constraint. In the model, the inner-layer model is aimed at a lower total daily operating cost of the ICDS by optimizing the EVs’ charge- discharge power of each moment, and the outer-layer model is aimed to minimize the loss of the distribution network by optimizing the location of the node that ICDS is connected to the distribution network. Both the economy of the ICDS and the security of the distribution network are all improved in the multi- objective double-layer optimization model. Particle swarm optimization (PSO) is applied for the iterative solution and global optimization. Finally, a modified IEEE 33-node system is performed to prove the rationality and feasibility of the model.