In this paper, a new energy storage system (ESS) is developed for an innovative subway without supply rail between two stations. Because operating voltage, maximum braking current and discharge depth of supercapacitor have a great influence on its rational configuration, there are theoretical optimum values based. Provide capacitors, capacitors/battery composite solutions, as a traction power supply system, provide energy when the vehicle starts, accelerates, and travels, and provide efficient energy recovery and storage units when braking, realizing fast charging in seconds, meeting the requirements of. ought after by researchers. Mathematical models of the train, driving.