Optimization of DC Distribution Network Considering SOP Topology Reconfiguration under EV Access

The disorderly access of electric vehicles (EV) will cause the voltage deviation and network loss of the distribution network to increase, which will affect the safe and stable operation of the system. Therefore, the distribution system needs to be continuously upgraded and optimized. In this paper, a soft open points (SOP) topology reconfiguration optimization method for DC distribution network is proposed. Firstly, the EV charging load demand model is established. Based on the regulation characteristics of SOP on power flow distribution, the SOP model suitable for DC distribution network is established, and the SOP equivalent model is established according to its external characteristics. Secondly, aiming at the lowest loss of the distribution network system, the simulated annealing method is used to optimize the SOP access position of the DC distribution network. Finally, the modified IEEE33 node DC distribution system is selected for simulation verification. The proposed optimization method can effectively reduce the system loss and voltage deviation of the DC distribution network.