The main electrical load in the port area is loading and unloading equipment, which has large power impact, frequent starting and braking, and will generate feedback energy to inject into the power grid. The super capacitor energy storage device can quickly track and control the port load power to achieve the purpose of balancing the load, which can effectively prevent and suppress the occurrence of oscillation. At present, Baina is the only supplier of 3MW energy storage system in the world. The super capacitor energy storage device provided by Baina for Yangshan deep water port in 2011 is the largest set of active tidal current control device based on super capacitor in the world. This set of energy storage device can effectively carry out demand side management, eliminate countercurrent, balance load, reduce load peak to valley difference, and reduce power change rate, so as to improve system stability and equipment utilization, and reduce power supply cost . The success of Yangshan Port energy storage project will promote the development of port active power flow control technology.