系统故障条件下分布式电源分类及含DG的配电网运行与控制相关问题的研究

项目名称： 系统故障条件下分布式电源分类及含DG的配电网运行与控制相关问题的研究

项目编号： No.50877021

项目类型： 面上项目

立项/批准年度： 2009

项目学科： 金属学与金属工艺

项目作者： 孙鸣

作者单位： 合肥工业大学

项目金额： 31万元

中文摘要： 如今，以可再生能源和洁净能源为动力的分布式电源（DG）将不断地向配电网渗透。DG的接入，改变了配电网潮流单向流动的特征。当含DG的配电网发生故障时，DG和配电网彼此之间在运行、保护与控制等方面将产生的交互影响。 本项目着重研究了系统故障条件下DG的接入对配电网短路电流、中压馈电线路一次重合闸和变电站备自投应用、是否构成微网运行以及对配电网继电保护等方面的影响。研究结果表明：若不考虑DG构成微网运行，则减小DG接入带来影响的最佳办法是正确判断故障的出现有没有导致DG与主网解列。如解列，立即切除DG。如未解列，DG可继续并网，此时在考察DG对故障点短路电流以及对故障回路继电保护的影响时，要综合考虑DG的电源类型、相对与主网供电容量的比例大小以及其所提供的短路电流持续时间；若要考虑DG构成中压微网运行，建议采用允许短时间断供电的孤岛运行方式，该方式对线路重合闸、变电站备自投的应用不会产生影响，但微网内继电保护存在的问题尚待进一步研究解决。 本项目的研究成果已通过国际会议和国内核心科技期刊予以发表，并获得国家发明专利一项，项目成果可以为分布式发电在配电网的广泛应用提供一定的理论和技术支持。

中文关键词： 分布式电源；配电网；微网；故障；交互影响；

英文摘要： Nowadays, the distributed generator (DG) which uses the renewable energy and clean energy for power will continually penetrate into the distribution network. The connection of DG has changed the one-way flow characteristic of distribution network power flow. When the network containing DG is at fault, the distribution network and DG will have some mutual effect with each other in terms of operation, protection and control. This project has particularly studied the effect of DG connection in the system fault on short-circuit current of the distribution network, single shot reclosure in medium voltage feeder line, application of spare power source automatic switch in the substation, possibility of microgrid operation as well as protective relaying in distribution network and so on. The results of the study show that: with consideration of the microgrid operation of DG, correctly judging whether the fault results in DG's disconnection with the main grid is the best way to reduce the impact of DG connection. If the disconnection occurs, remove the DG immediately. If not, DG can continue to connect with the grid. And here when in the investigation of DG's effect on short-circuit current at the fault point and protective relaying in the fault circuit, comprehensive consideration of the power type of DG, relative proportion of power supply capacity compared with the main grid and the duration time of the short circuit current provided should be made; If DG's medium voltage microgrid operation is considered, island operation mode of allowing power supply interruption for short time is recommended, and the mode will not affect the application of reclosure for lines and spare power source automatic switch in the substation, but the problems of protective relaying in microgrid still require further study and solution. The research findings of this project has been published through the International Conference and The Core Journal of China Technology, and got one national invention patent. The findings of the project can provide certain theoretical and technical support for the wide application of distributed generation in the distribution network.

英文关键词： distributed generator；distribution network；microgrid; fault；mutual effect