Various application domains are considered. Energy storage is one of the hot points of research in electrical power engineering as it is essential in power systems. It can improve power system stability, shorten energy generation environmental influence, enhance system efficiency, and also raise renewable energy source penetrations.
The application of energy storage technology in power system can postpone the upgrade of transmission and distribution systems, relieve the transmission line congestion, and solve the issues of power system security, stability and reliability.
The pumped storage power station (PSPS) is a special power source that has flexible operation modes and multiple functions. With the rapid economic development in China, the energy demand and the peak-valley load difference of the power grid are continuing to increase.
During entry and exit of distributed generations, the power is out of balance in a short time, the energy storage facility can be applied to realize fast charging/discharging control, and active power is able to be controlled smoothly and instantaneously to guarantee the voltage stability of significant load.
The development and expansion of energy storage technology not only depend on the improvement in storage characteristics, operational control and management strategy, but also requires the cost reduction and the supports from long-term, positive stable market and policy to guide and support the healthy development of energy storage industry.
Due to rapid development of energy storage technology, the research and demonstration of energy storage are expanding from small-scale towards large-scale. United States, Japan, the European Union have proposed a series of policies for applications of energy storage technology to promote and support industrial development [12 – 16].