Siting And Sizing Of DG For Microgrid Based On Improved Ant Colony Algorithm

With the growing demand for electricity, the scale of power grids was expanding and its disadvantages such as high cost,difficult to run becoming apparent, so the distributed generation was put forward. Though the distributed generation has many advantages such as less investment,flexible,high energy efficiency and environmental, but it also will brought many problems to grid voltage,line tide,short circuit current,reliability of grid,power quality and so on. In this case, the technology of micro-grid which integrated distributed generation and load provides a good solution. The technology of micro-grid can reduce energy loss,delay power line upgrade time and decrease the costs. But if the location and capacity of distributed generation does not inappropriate, it not only can't reduce the power loss, but also will increase power loss and reduce the reliability of power supply. To solve these problems, this paper main research the issue of distributed generation's location and capacity in micro-grid so as to optimize the location and capacity of distributed generation to achieve the most economically optimal operation of micro-grid.This paper take the ant colony algorithm which has strong global search ability as to solve the problem of the distributed generation's site and size on the micro-grid. Introduces the technology of distributed generation and its'common form and analysis of distributed generation's implications to the network current, network losses, power quality, voltage and reliability. For the basic ant colony algorithms exists two disadvantages such as search for too long and easy search into a local optimum, this paper through improved the basic ant colony algorithm's adjustment factor's value and method of refreshing pheromone to resolve the problems, propose a new ant colony algorithm, example shows that the new algorithm is feasible and effective. Under the constraint condition, paper treats the total cost of micro-grid planning and operation as the target, established the mathematical model of the issue that the location and capacity of distributed generation in micro-grid, given the target evaluation function,solution approaches and solving steps based on improved ant colony algorithm.Finally the paper in the Eclipse development environment using the Java programming language programs and implements the new algorithm, selecting a city grid as the instance object for the simulation, results show that the introduction of distributed generation into grid so as to construct micro-grid can get better social and economic benefits, the results also illustrate that the proposed algorithm can effective resolve the problem of the location and capacity of distributed generation in micro-grid.