【作者】 汪冬辉； 姚旭； 张坤贤； 许文宣； 焦在滨； 康小宁；

【Author】 WANG Donghui;YAO Xu;ZHANG Kunxian;XU Wenxuan;JIAO Zaibin;KANG Xiaoning;Xi’an Jiaotong University;Gansu Province electric power company;

【机构】 西安交通大学电气工程学院； 甘肃省电力公司；

【摘要】 随着储能和控制手段的发展,微网的独立运行技术已经在近期的几个示范工程中得到了应用。这类微网通常建在距离主网较远并且自身负荷不大的地方,完全依靠自身电源供电,大大减少了输电线路的投资。由于其包含大量的电力电子设备,故障特征不同于常规电网,亦与并网运行的微网有所区别,在配置保护时必须考虑其特性。本文根据浙江某岛独立运行微网的实际拓扑,在PSCAD软件中建立仿真模型,分析几种常用保护在独立运行微网中的适应性。分析结果表明,常用的电流保护在该类微网中会受到较大影响,配置时必须考虑到其适用条件;馈线上的纵联电流差动保护可以正常运行;由于电网较弱,故障期间电压跌落大,且故障期间电源的阻抗不稳定,功率方向元件以及序分量方向元件均难以使用。更多还原

【Abstract】 Accompanied by development of energy storage and control strategy, the technology of independent microgrid is applied in some demonstration project recently. This type of microgrid is usually built in the area, which is far from the main grid and owns little load. Its power supply is all depend on its own source, which result in less investment on electric transmission line. As it includes lots of electronic devices, its fault feature varies from normal grid and microgrid connected to the grid. As a result, it is necessary to take this feature into consideration when designs relay scheme. This paper model an independent microgrid in PSCAD according to the microgrid in a certain island in Zhejiang, then analyze the adaptability of some normal relay. The result shows that current protection is affected, pilot protection can work well, power and sequence components directional element are not suitable as the lower voltage and unstable impedance during the fault.更多还原