Optimal Control Method of an Energy Storage System for Energy Saving

From the viewpoint of energy saving, the optimal control method of stationary energy storage systems is a method of minimizing of the total energy supplied from all the related traction substations. The purpose of this paper is to find the optimal charging/discharging power control method of the energy storage system under the condition in which speed profiles and driving operations of all trains are fixed. We make some assumptions to model this problem as a mathematical optimization problem. In this paper, we introduce some calculation results obtained by varying parameters. We also indicated that this mathematical optimization model can calculate the maximum effect on energy saving which is useful to design the energy storage system. In addition, we confirm the validity of this mathematical optimization model and estimate the effects of the energy storage system on energy saving.