Double-Q based Optimization of Energy Storage Investment Capacity in Distribution Networks

In recent years, the integration of high proportions of clean energy into power systems has brought challenges to their reliability, and the large-scale commercial application of energy storage (ES) provides strong support. However, the market mechanism for energy storage is not mature enough, and the current pricing method for network charges is mainly used for system members with a single power flow direction such as power sources and loads, without addressing energy storage resources that can exchange power bidirectionally with the system. By responding to real-time electricity prices and load curves with charging and discharging strategies, an energy storage operation mode that maximizes the profits of the storage owner and is beneficial to the stability of the power network can be obtained. Based on the long-term incremental cost method, the economic benefits of energy storage in relieving network congestion and deferring investment are quantified to determine the network charges for energy storage resources. Based on the dynamic investment efficiency evaluation method, the returns of energy storage investors over the entire battery life cycle are analyzed and evaluated, and verified in the IEEE 33-node distribution system.