| Micro-Grid is a small power supply system,which consist of many distributed generation,energy storage devices,energy conversion devices,load,monitoring and protecting devices.Compared with the traditional power grid,the Micro-Grid have significant advantages,for example,the lower operation cost,the smaller pollution,the higher utilization rate of renewable energy and it can significantly reduce user’s electricity cost.Since 21st century,as the energy crisis coming up and aggravating,Micro-Grid which can be supplied by distributed generation is becoming a research hotpot.At present,the major factor which restrict the further development of the Micro-Grid is how to control the micro grid system with a reasonable method.Many scholars have been launching a lot of research,and economic operation of power grid is one of the core problem in the research.In this paper,Micro-Grid includes the power supply,micro gas turbine,fuel cell and energy storage device,and the main research goal is the economic performance.The main research contents are as follows:Firstly,analyzing the characteristics of the Micro-Grid,building the mathematical model of the components in Micro-Grid based on matlab/simulink platform,and analyzing the influence of the external parameters on these distributed generations.Secondly,we can establish the cost evaluation function according to the operation of Micro-Grid,such as the fuel costs,the electricity costs,maintenance costs and so on.Then,solving the optimization scheduling problem with improved particle swarm optimization algorithm,and adaptive adjustment of weight coefficient according to the particle concentration is applied to this algorithm,so we will get a chaos-particle swarm algorithm with adaptive adjustment of weight coefficient when particle swarm algorithm combined with chaos.Now we can get the optimal control strategy to improve the team working of distributed generation in system,which can reduce the economic cost of the Micro-Grid.Thirdly,considering the impact of random factors in Micro-Grid,we can use the chance constrained programming theory to correct the economic optimization model,and analyze the example which considers the prediction error’s influence on the economic operation.Finally,considering the influence of the rated power,we set up the off-gird economic optimization model with integrity load shielding,and analysis the effect on the economic operation strategy.The results show that Micro-Grid has certain advantages compared with traditional power mode,the prediction error and integrity load shielding can increase the economic cost of the Micro-Grid operation. |
