基于风机弱馈特性的集电线路故障方向判断  

A novel fault direction recognition method in collector line based on weak-infeed property of wind turbines

作　　者：沈金青 黄宏盛 黄涛[3] 钱伟杰 Shen Jinqing;Huang Hongsheng;Huang Tao;Qian Weijie(State Grid Zhejiang Jiashan Power Supply Company,Jiaxing 314100,China;State Grid Zhejiang Jiaxing Power Supply Company,Jiaxing 314033,China;NR Electric CO.LTD,Nanjing 211102,China)

机构地区：[1]国网浙江嘉善县供电公司,浙江嘉兴314100 [2]闰网浙江嘉兴供电公司,浙江嘉兴314033 [3]南京南瑞继保电气有限公司,江苏南京211102

出　　处：《可再生能源》2018年第8期1192-1196,共5页Renewable Energy Resources

基　　金：国家电网科技项目(5211JX16000C)

摘　　要：风电场集电线路发生反方向故障时,集电线路电流保护可能因流过反向短路电流而误动,须安装方向元件。针对传统功率方向元件受集电线路接线方式及风机低电压穿越方式影响而无法正确动作的问题,提出了一种新型的集电线路故障方向判断方法。该方法利用在线路发生正、反向故障时,因风机的弱馈特性保护所感受背侧系统等效阻抗存在明显差异的特征,能够快速可靠地判断出故障方向。文章搭建了集电线路仿真模型,通过仿真试验验证了该方法应用于集电线路的适应性和正确性。The reverse short-circuit current due to a backward fault may cause current protection malfunction in wind farm collector lines. Thus,directional relay is required for collector line.Traditional power directional relays often suffer incorrect operations affected by the connection way of collector lines and low voltage ride through（LVRT） measures. To solve this problem,a novel fault direction recognition method in collector lines is proposed. This method utilizes the significant differences of system equivalent impedances behind protection relay during forward and backward faults,which are caused by the weak-infeed characteristic of wind turbines. With this scheme, the fault direction can be judged rapidly and reliably. Moreover,a simulink model for collector line is built,the simulation results indicate that the method proposed is available and accurate in collector lines with better adaptability.

关 键 词：集电线路 弱馈 故障方向 等效阻抗 

分 类 号：TK89[动力工程及工程热物理—流体机械及工程] TM773[电气工程—电力系统及自动化]