摘要
对高压线路振荡闭锁实现方法进行了研究,指出目前的振荡闭锁方法降低了距离元件的性能,并提出了一种新的振荡闭锁实现方法。根据保护安装处的电压、电流和距离元件整定阻抗可以计算出距离元件保护范围末端的电压,保护安装处电压和距离元件保护范围末端电压之间的夹角反映振荡的进程,该夹角在振荡中周期性变化,变化周期与振荡周期相同,该夹角数值较小时,距离元件不会误动,该夹角达到一定数值时,距离元件将会误动。新判据通过计算保护安装处电压和距离元件保护范围末端电压之间的夹角来实时开放和闭锁距离元件,在该夹角较小时开放距离元件,在该夹角较大时闭锁距离元件。并分析了系统中发生故障时该判据的性能,该判据不受区外故障的影响,在发生区内故障时能正确工作,和振荡周期自适应,在系统未振荡或振荡中心不在距离元件保护范围内时不会动作。动模数据仿真验证了该判据的有效性。
As the present swing blocking method degrades the performance of distance element,a power system swing blocking element is proposed for high voltage line protection.The voltage at the end of the distance element scope can be calculated with the voltage and current acquired and the impedance setting of distance element.The angle between the acquired voltage and the calculated voltage changes periodically during power system swing,which may cause the misoperation of distance element.A swing blocking element is presented,which disables the distance element when the angle is larger.The performance of swing blocking element during system fault is analyzed,which indicates that,it is not influenced by the external faults and works properly during the internal faults.Adaptive to the swing period,it is not functioning when power system is steady or the swing center is not within the protection zone.Dynamic system model data simulation result shows its validity.
出处
《电力自动化设备》
EI
CSCD
北大核心
2011年第4期7-12,16,共7页
Electric Power Automation Equipment
基金
国家自然科学基金项目(50677051)~~
关键词
高压线路
距离保护
振荡闭锁
自适应
HV line
distance protection
swing blocking
self-adaptive
