267 Investigation of Optimal Battery Scheduling with Fuzzy Control
In this paper, energy management of a microgrid is investigated using fuzzy logic approach. Efficient utilisation of storage devices among the multiple sources of generation dispatch within a typical microgrid yields reduced economic and environmental generation costs. The complexity arises due to the uncertainty of load demand, weather conditions, availability of innovative energy technologies, charging/discharging rate of batteries, price for the installed storage device and other active
... d other active generation and maintenance costs. In microgrid, the overall cost objective function is subjectively derived from three cost parameters specifically, the power generation cost of each distributed generation unit based on its consumption rate of type of fuel used, the energy trade between the main grid and the microgrid, and the maintenance cost that is assumed to be proportional to the power generation of each unit. Lead acid batteries are preferred as storage devices due to its economical cost and high efficiency of charging and discharging rates. However its life time gets significantly affected due to increase in depth of its discharge. From energy management point of view the maintenance cost plays major role in the overall cost of microgrid. Although battery scheduling is considered as a deterministic approach, however due to uncertainty in prediction of other related parameters, a simplified fuzzy logic approach of scheduling of the battery storage devices is suggested within a typical medium sized microgrid. The proposed methodology includes the uncertainties related to the forecasting of load pattern, availability of solar energy, charging and discharging rate of batteries, battery state of charge, electricity pricing and other renewable energy resources available in the region. The result shows that the battery scheduling has been optimised that has reduced the battery maintenance cost considerably through lower depth of battery discharge which helps in extending its operational lifetime. This intelligent opportunity battery scheduling approach shall certainly optimise the overall cost of microgrid operation.