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With the rapid development of photovoltaic power generation and electric vehicles (EVs), the PV-storage based charging station as well as its economic and safe operation have received more attention. In order to reduce the adverse effects of disorderly charging of electric vehicles on the stable operation of the distribution network, an orderly charging optimization model considering the benefits of electric vehicle (EV) users and the distribution network to minimizing the daily operating cost of PV-storage charging station is established in this article. On this basis, a multi-time-scale coordinated optimization control strategy is proposed, which will update the operation of the charging station on the two time scales of day-ahead (long-term) and intra-day (short-term) based on model predictive control (MPC). Finally, the simulation analysis is carried out in combination with the charging station in a park type micro-grid (MG) system. The experimental results verify that the optimization strategy can effectively improve the safe and economic operation level of the charging station during the dynamic real-time operation process, realize the orderly charging of the charging load, improve the ability to absorb renewable energy and ensure an optimal balance between charging demand and energy supply in this system.

In this paper, we propose a robust planning method for regional integrated energy systems(IES) considering the uncertainty of cold, hot and electric multi-energy loads. Based on the improved energy hub (EH) model, we established a regional integrated energy system model, which includes CHP, electric boilers, gas boilers, electric chiller, absorption chiller, battery, thermal storage and cold storage. In addition, 0–1 variable of equipment selection is introduced to select and optimize the capacity of each equipment. The polyhedron set is used to describe the uncertainty of multi-energy load, and a robust planning model is formed and equivalent transformed. Finally, the capacity planning model is realized by programming in MATLAB, and the optimal configuration is solved by CPLEX. The result shows that the conservatism of system planning can be controlled by robust measure, and the optimal plan can guarantee reliability and economy of the system at the same time. It also reflects the multi energy complementary integration optimization benefits of IES.

Load asymmetric or asymmetric fault will cause output power fluctuation and three-phase current imbalance of micro-grid storage system, which affects the power quality and distribution network system stability. A control strategy of voltage stability and power balance based on novel current decoupled is presented to deal with the problem in this paper. The energy storage converter mathematical model in the state of voltage unbalanced is established, and the mechanism of power fluctuation and three-phase current variation is revealed. The complex coefficient filter is proposed to control the positive sequence voltage and negative sequence voltage independently, and current vector control is realized by the quasi-PR controller. On the basis of decomposing positive and negative sequence current into active and reactive components, the command current values with negative sequence current suppression and power fluctuation suppression as control objectives are given respectively, and the expression of three-phase current is deduced. Case analysis on typical Micro-grid energy storage systems is shown to confirm the feasibility of this method.