A Study Of Energy Management Strategy In The Isolated Microgrid

In recent years, with the energy crisis and the environment pollution becoming more and more serious, the renewable energy utilization such as solar energy and wind energy catches considerable attention, hence microgrid technology provides an effective approach to the comprehensive and effective utilization for renewable energy. Microgrid usually runs as grid-connected mode or as isolated mode, while isolated microgrid is mainly used in a situation that is far away from power grid and has less manual maintenance. The economic performance of the system is the goal of isolated microgrid. Therefore, it is necessary to carry out energy management for isolated microgrid to realize economic optimization of system operation. For the isolated microgrid which improving the economic performance is the aim of the system, it is necessary to take the cost as a constraint to the energy management strategy to strive for a higher economic benefit.In this thesis, a isolated microgrid energy management model, which considers investment costs, operation and maintenance costs, fuel costs, startup and shutdown costs, based on economic target is proposed. Then the Particle Swarm Optimization(PSO) and Genetic Algorithm(GA) theories and their advanced usage are respectively introduced in this paper, and isolated microgrid energy management strategies based on the improved algorithm are presented. Besides, by using Matlab, two control strategies are simulated, while the feasibility of establishing the energy management model of isolated microgrid under the two control strategies is verified by comparing the two control strategies. Furthermore, a energy management platform in isolated microgrid is designed, including hardware, communication and software. As programmable Logic Controller(PLC) plays a role of the core of the energy management platform, PLC runs microgrid system control program and energy management program, and communicates with the rest of the system for real-time, in order to achieve the island based microgrid system control and optimization. Last, the experimental results of the energy management platform of isolated microgrid are given and compared to the simulation results to verify the feasibility of the isolated microgrid energy management platform.