UPFC串联变压器匝间保护新原理研究  

A Novel Protection Principle for Turn-to-Turn Fault of UPFC Series Transformer

作　　者：曹虹 王兴国 周泽昕 柳焕章 杜丁香 蔡文瑞 CAO Hong;WANG Xingguo;ZHOU Zexin;LIU Huanzhang;DU Dingxiang;CAI Wenrui(State Key Laboratory for Security and Energy Saving(China Electric Power Research Institute),Haidian District,Beijing 100192,China;Central China Branch of State Grid Corporation of China,Wuhan 430077,Hubei Province,China;School of Electrical&Electronic Engineering,North China Electric Power University,Changping District,Beijing 102206,China)

机构地区：[1]电网安全与节能国家重点实验室(中国电力科学研究院有限公司),北京市海淀区100192 [2]国家电网有限公司华中分部,湖北省武汉市430077 [3]华北电力大学电气与电子工程学院,北京市昌平区102206

出　　处：《电网技术》2020年第4期1568-1575,共8页Power System Technology

基　　金：国家电网公司科技项目:弱电磁耦合元件轻微故障识别及定位技术研究(SGSDZZ00FZJS1800841)。

摘　　要：串联变压器是统一潮流控制器(UPFC)系统的重要组成元件。由于其特殊的结构及接入系统方式,串联变压器网侧绕组纵向电压随UPFC控制方式变化而变化。同一短路匝比匝间短路时,串联变压器差动电流与网侧绕组纵向电压幅值呈正相关,传统电流差动保护作为串联变压器匝间短路的保护灵敏性和可靠性不足。提出了一种新型的串联变压器匝间保护原理,构建了与网侧绕组纵向电压幅值呈正向线性关系的自适应动作门槛,以及根据两侧电流幅值自动调整的制动量,极大地提高了保护的灵敏性和可靠性,在实际工程中具有良好的应用前景。RTDS仿真结果验证了传统保护的不足及新型保护的优越性能。Series transformer is a very important part of unified power flow controller(UPFC) system. Due to the special connection mode of series transformer, the longitudinal voltage of line side winding varies according to UPFC control mode. When turn-to-turn faults of series transformer with the same short-circuit turns ratios occur, there would be a positive correlation between differential currents and longitudinal voltages of line side winding. Traditional current differential protection may be less sensitive or even refuse to operate in certain fault cases. A novel protection principle for turn-to-turn fault of UPFC series transformer is put forward in this paper. An adaptive tripping threshold positively correlated with longitudinal voltage of line side winding is built up. A restraining quantity adjusted automatically according to magnitudes of both side currents is proposed. The novel protection principle has higher reliability and sensitivity and good applicability in practical engineering. RTDS simulation tests verify the shortcomings of traditional protection and validity and superiority of the novel protection.

关 键 词：统一潮流控制器 串联变压器 匝间短路 网侧绕组纵向电压 

分 类 号：TM721[电气工程—电力系统及自动化]