Evaluation Method For Operation Efficiency Of Distribution Networks And Its Application

Distribution network connect the power grid and customers, meanwhile, it is the last step of power production, transmission and consummation, How to improve the operation efficiency of the distribution network has been plagued with network operation researchers. From safety and economy point, providing an accurate and efficient assessment method for power grid, can bring huge gains to the grid.With the construction of the intelligent distribution network, the voltage level is diversified and a large number of distributed generations are integrating. The characteristics of distributed generations are not easy to control and intermittent. It caused a series of problem, for example, topology of distribution network intelligent switch, capacity and location optimization, distribution network static security margin, fault splitting island operation efficiency analysis.In the process of distribution network safety, economic evaluation has been lack of comprehensive integrated approach. This paper respectively from the point of view of distribution network safety, economy, put forward a variety of evaluation indexes, and quantitative evaluate the efficiency of the distribution network. For the distribution network with DGs, to study the effect of distributed power on power distribution network and the access efficiency of power supply, then quantitative evaluation has been given. Finally based on the angles of evaluation indexes, combining different optimization objectives, respectively established evaluation model efficiency of multi-objective.In this paper has did research on the power flow calculation and optimization and distributed power distribution network access, and did power flow calculation and optimization calculation at the same time, form a distribution network operation optimization method. When making operation optimization for distribution network make plan into the influence of distributed power supply, make the distribution network loss smaller, and maximize the output of the distributed power (DG).IEEE33 is chosen as an example to demonstrate the effectiveness of the proposed evaluation index and the access of the DG location and access to the capacity of the single objective and multi-objective optimization. The result shows that the proposed distribution network operation efficiency evaluation index can comprehensive and effective evaluation the distribution network status, for determine position and capacity of DG integration optimization can achieve good effect.This paper introduces flow calculation of general distribution network and distribution network with distributed power, and containing a emphasis and difficulty of efficiency evaluation of the distributed power supply, carefully summarize power flow and efficiency indexes and present research situation of distribution network with distributed power. Introduced the power grid operation efficiency evaluation index method in the past, and the method of evaluation index system are expounded, establish the economical efficiency of power grid comprehensive evaluation index of electric network loss, voltage stability, voltage deviation and power supply ability, and establish mathematical formula applied to subsequent flow calculation. Established distribution network with distributed power operation efficiency evaluation model:analyz the mainstream of multi-objective optimization model of distribution network, determined to solve the problem of objective function, determines the branch, node, such as voltage, power constraints. Using particle swarm optimization (pso) algorithm solving the DG multi-objective optimal allocation problem, so as to obtain the power grid operation efficiency optimal DG installation location and installation capacity, for the intelligent power distribution network planning provides decision-making support for optimized configuration of distributed power supply.The superiority of multi-objective optimization model and the effectiveness of the application of particle swarm optimization (pso) are validated by simulation examples and comparison, and have analysised the effect of optimizing the allocation of DG on distribution network operation efficiency. Finally, summary the result of the research on the comprehensive, based on this, points out that the further research work in the future.