A Economic Dispatch Method of Energy Storage Systems under Time-of-use Pricing in Microgrids

The energy storage system (ESS) plays a vital role in the reliable operation of a micro-grid. In the autonomous mode operation, the energy storage system is expected to support the difference in power requirements and maintain the frequency and voltage. In grid-connected mode, the economic dispatch of ESS achieves peak load shaving and maximum economy. A detailed analysis shows the power management strategies of energy storage systems for a micro-grid in grid-connected and islanded mode, and based on this analysis, this paper presents a economic dispatch method under time-of-use pricing. The proposed power management strategies, based on a combination droop control and a economic dispatch method, increase the power supply reliability and realize peak load shaving and maximum economy. A study case is presented to investigate the economic benefits of the ESS, and the results contribute to discuss the applications of the economic dispatch method under various operating conditions and market policies.