Taiwan’s policy goal of reaching 27GW of renewable energy installations and 20% of renewable energy power generation in 2025 has made the power system inevitably faced with rapid changes, stability and reliability issues. In order to solve this problem and comply with the regulations of the Electricity Industry Law to open diversified resources as auxiliary service sources, Sermatec Energy has configured a set of 12MW/12MWh energy storage system for this project, which will participate in Automatic Frequency Control (Automatic Frequency Control, AFC) frequency modulation service, using the advantages of fast charging and discharging of energy storage, enables the energy storage system to follow the fluctuation of the load of the power system, and actively adjust the charging and discharging actions to maintain the stability of the system frequency.