Modern energy system presents the trend of "scenery leading and multi-source coordination". Accepting more fluctuating power supplies and loads with different characteristics puts forward higher requirements for the flexibility of the system, and the role of energy storage resources in the operation of the system is becoming more and more important. At present, the understanding of energy storage power stations is mostly limited to peak shaving and valley filling, easing the tension between power supply and demand and so on. In the future, the value of energy storage will be more reflected in realizing the dynamic balance between power supply and demand, smoothing output fluctuation and load change, improving the consumption of renewable energy, providing auxiliary services in the power market, so as to improve the safety, economy and flexibility of power grid operation and realize the coordinated and optimal operation of energy storage and modern power system.