Energy storage system scheduling for an isolated microgrid

A knowledge-based expert system (KBES) is proposed for the scheduling of an energy storage system (ESS) installed in a wind-diesel isolated power system. The program optimises the cost of operation by determining the diesel generation and the charging/discharging cycles of the storage system from the wind and load profiles one hour in advance. The rules created aim to minimise the use of the dump load normally associated with diesel operation. The results are compared to an offline optimisation algorithm applied to the same power system and ESS size that has a 24-h lookahead. The results obtained show that by minimising the energy wasted through the dump load with the use of the ESS and KBES controller, the required diesel generation is reduced, therefore reducing operation costs and emissions.