Energy Management in Multi-Microgrid System with Community Battery Energy Storage

Abstract

Conventional techniques suggested for energy management in the multi-microgrid system uses energy trading between producer and consumer microgrids as a prime strategy. However, this paper explores various other options for energy management system (EMS) to fulfill consumer load demand such as trading with the main grid, buying power from producer microgrids or buying from the battery energy storage (BES). Rule-based and optimization approach is suggested for charging and discharging BES based on grid price band allocation. Producer microgrids with surplus power are allowed to select their strategy regarding the fraction of surplus power they want to trade depending on the bid placed by the consumer microgrids. A three-step multi-microgrid optimization mechanism is proposed. In the first step, realtime electricity price is categorized into two different limits i.e., an upper limit and lower limit. In the second part, consumer representative (CR) calculates the bid for buying power from producer microgrids and producer microgrids adjusts its power consumption looking at the bid placed CR. In the third step, optimization is performed by EMS for minimizing the overall operational cost of the system including the cost of BES. A detail case study is presented to check the effectiveness of the proposed energy management technique.