Analysis And Design Of Evaluation System About The Distributed Generation Access To Distribution Network

With the increasing energy demand and some drawbacks of traditional power system, distributed generation has been widely applied. Therefore, on the basis of traditional centralized generation and long-distance transmission power, it’s becoming more and more important to develop distribution technologies and to establish a new grid with distribution generation. However, due to the characteristics that wind power and PV power is intermittent and fluctuant, it will bring many adverse effects when connected to the distribution network.Firstly, several of the most commonly used applications and distributed power technology development status are introduced. Then the impacts on voltage and distribution network power losses are analyzed from distribution network topology after distribution generation is accessed. After theoretical analysis of the impacts, model of wind power based on simulation platform into the grid is built up. And the variation of the effect about voltage and distribution network power losses under different conditions by changing the capacity and location of distributed generation is simulated, which can guide operators where and how much of the output of distributed generation should be accessed into the distribution network.Introduce the application of battery storage system (BESS) in distributed generation and analyze the shortcomings of traditional low-pass first order filter control algorithm. In order to overcome the problem, hysteresis control is added based on low-pass first order filter control algorithm. This method is proved that can reduce the times and depth of charge and discharge of BESS and increase the life time of the battery.Based on qualitative analysis, evaluation index system is established for the assessment of voltage quality and distribution network power losses, which can achieved the quantitative impact assessment of voltage quality and power losses. Therefore, by estimating the voltage quality and distribution network power losses under different location and output of distribution generation, it’s possible to achieve maximize benefits of the network. Achieved evaluation system software development and used it to finish the simulation experiment of evaluation.