Research Of Multi-objective Economic Dispatch Model For A Micro-grid Based On Particle Swarm Optimization

Micro-grid can integrate the advantages of distributed generation, coordinate distributed power and the power system, make full use of decentralized energy combined with the local load, energy storage devices and associate monitoring and protection devices, to be formed a new micro power system that have a capacity of self-control, protection and management. But there are many problems such as how to achieve micro-grid's operation control, energy management and scheduling. Among them, the economic performance of micro-grid is a difficulty. Micro-grid which is characterized by small and large quantity DG has dispersed scheduling risks, and improved power supply reliability; the micro-grid wind and PV unit generating capacity is easily effected by weather conditions, ambient temperature, wind speed, sunshine radiation; DG equipment failure rate is changed with the environmental conditions and time, all these random factors have some impact on the electricity reliability of micro-grid system. Therefore, Micro-grid including random multi-energy such as photovoltaic, wind power, considered the pure cost of power generation or environmental problems of economic dispatch is significant inadequacies.Based on this, this paper study the multi-objective economic dispatch of micro-grid. The main work is presented as follow:(1) The model and operating characteristics of DG described as follow: the random model of solar power and wind power, the charge and discharge model and energy balance model of battery and accumulator, and analyze energy-consuming characteristics model of micro-turbine and fuel cell.(2) A multi-objective economic dispatching model for the micro-grid is proposed. These objectives are to minimize the generating cost, the loss of customers and the impact on the environment. And the variables and parameters of the model are analyzed and calculated in detail.(3) As to solving the multi-objective optimization model problem, it based on fuzzy optimization theory, and used the maximum fuzzy satisfaction degree method transform the multi-objective optimization problem into a non-linear single-objective optimum problem which is solved by using particle swarm algorithm; and specifically presented the approach of objective function, constraints in the particle swarm optimization in order to avoid local optimal to ensure the solution feasibility and global optimum.(4) Simulation results show that multi-objective model is better than single-objective model in reflecting the actual operation characteristics of micro-grid more precisely and reaching a higher reliability and environmental effects at as low operation cost as possible. It shows that the method used in this paper is effective by comparing the analysis.