行波测距失效点处的故障测距研究

The Study on Faults Location on Failed Point ofTraveling Wave's Method

随着现代微电子技术的飞跃发展和对行波传播规律以及对暂态信号获取方法的进一步掌握,行波故障测距装置已广泛应用于超、特高压输电线路上,但行波测距方法有其固有的缺陷。文章在对行波测距盲区分析研究的基础上,提出了两种能消除行波故障测距盲区的故障定位算法。这两种方法都是利用故障线路重合脉冲来实现故障定位。算法1是将重合闸脉冲进行三次B样条分析后,根据合闸脉冲和合闸脉冲在故障点处的反射波之间的时间差来进行故障定位;算法2是利用故障线路重合过程中一端线路处于合闸而另一端处于断开状态,利用故障边界电流进行构造单端故障定位算法;并以特高压交流输电线路为研究对象,来进行算法的仿真验证。仿真结果表明,该方法能准确地进行故障定位,其精度不受故障点过渡电阻、故障类型、对端系统的阻抗及故障距离的影响。

With the rapid development of the micro - electronic technology and further understanding of the rule of the traveling wave, the traveling wave fault locating device has widely been applied to the EHV and UHV power transmission lines, but the traveling wave fault locating method has some limitations. The paper presents two fault location algorithms to eliminate the limitations of the traveling wave method. The algorithm I obtains the fault distance according to the time - margin between the reclosure pulse and the reflected pulse from the fault point by cubic B - spline wavelet and the algorithrn Ⅱ obtains the fault distance through the critical current of fault phase. The paper has finally verified the effectiveness and practicability of the algorithms. The simulation results show that the new method can accurately locate the fault and its accuracy is not affected by the transient resistance at the fault point, type of fault as well as impedance and fault distance of the opposite end system.