特高压母线故障暂态高频电流特征和母线保护应对措施  

Transient high-frequency current characteristics of UHV busbar fault and countermeasures in busbar protection

作　　者：吴崇昊[1,2] 陆于平[1] 侯喆[3] 刘小宝[3] 

机构地区：[1]东南大学电气工程学院 [2]国电南瑞科技股份有限公司,江苏南京210003 [3]国电南瑞科技股份有限公司

出　　处：《电力自动化设备》2008年第4期10-15,共6页Electric Power Automation Equipment

摘　　要：为计算复杂电力网络故障暂态分量的初始幅值、相位、频率和时间常数,开发了一套新的频域计算方法和研究工具。利用该工具系统分析了1000kV特高压母线故障暂态高频电容电流的特征和规律。分析结果表明高频电容电流的频率主要决定于系统参数和运行方式,幅值主要取决于故障初始电压相角和故障过渡电阻,时间常数主要取决于故障过渡电阻。在此基础上提出了谐波相量差动新原理。用相量法构造短窗滤波器从各支路故障电流中提取高频电流相量作为动作量,构成相量差动。与常规采样值差动相配合,可以将动作速度提高到半个周期。A trequency-domain research tool for calculating the initial amplitude ,phase ,frequency and time constant of fault transient components in complicated networks is developed. It is used to analyse the characteristics and laws of 1 000 kV UHV busbar fault transient high-frequency capacitive current. The result indicates that,its frequency depends mostly on system parameters and operating mode,the amplitude depends mostly on fault initial angle and fault transition resistance ,and the time constant depends mostly on fault transition resistance,based on which a new principle of harmonic phasor differential protection is suggested. A short data window filter is constructed by phasor approach to extract the high-frequency current phasor from fault current as the operating signal to form the phasor differential protection. Combined with conventional sampling value differential protection ,the operating time can be reduced to half AC cycle.

关 键 词：特高压 母线保护 电磁暂态 高频电容电流 谐波相量 

分 类 号：TM711[电气工程—电力系统及自动化]