特高压多回输电线环流不平衡及保护原理的研究

项目名称： 特高压多回输电线环流不平衡及保护原理的研究

项目编号： No.51277130

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 电工技术

项目作者： 李斌

作者单位： 天津大学

项目金额： 78万元

中文摘要： 特高压多回输电线是我国电网发展与建设的必然选择。特高压多回输电线路之间的电磁与静电耦合关系更加显著，线路参数频变特征明显，多回线内部的环流不平衡问题更加突出。鉴于环流不平衡对特高压多回线运行及保护产生的重要影响，本项目首先对特高压多回线的数字与物理仿真技术进行研究；并探索计及参数不对称、地线影响以及参数频变的相坐标系下的特高压多回线分析计算方法，为特高压多回线领域的深入研究奠定仿真试验和理论分析基础。在此基础上，研究多回线环流不平衡的产生原因及其关键因素；分析正常运行和故障情况下环流不平衡对功率传输、线路损耗以及主后备保护的影响。研究考虑参数频变的特高压多回线自适应电流差动保护原理；研究不受环流影响的、差动元件与方向元件相结合的横差保护新原理；研究利用环流在正常运行和故障时的差异性而实现的多回线保护新原理等。研究成果将为特高压电网的发展提供理论和技术支持，提高特高压电网运行的可靠性。

中文关键词： 特高压；多回输电线路；继电保护；环流不平衡；

英文摘要： Ultra high voltage (UHV) multi-circuit transmission line is an inevitable trend for the development and construction of the power system in China. However, the electromagnetic and electrostatic coupling among the lines and phases of UHV multi-circuit transmission lines is more significant and line parameters show a notable frequency-dependent characteristic, thus the problem of circulating unbalanced current of multi-circuit transmission line is more serious. Considering the great impact of circulating unbalanced current on operation and protection of UHV multi-circuit transmission line, digital and physical simulation technology is going to be researched systematically first. To lay a foundation of simulation and theoretical analysis for the in-depth research of UHV multi-circuit transmission line, this project will explore analysis and calculation methods, which take asymmetry parameters, influences of ground wires and frequency-dependent parameters into consideration, of UHV multi-circuit transmission line under phase coordinate system. On this basis, the causes and the key factors of circulating unbalanced current of multi-circuit transmission line will be studied and the influences of circulating unbalanced current under normal operation and fault condition on power transmission, power loss and main or back

英文关键词： Ultra high voltage；Multi-Circuit Transmission Lines；Protection Relaying；Circulating Unbalance Currents；