摘要
同塔双回直流线路极线间存在复杂的电磁耦合关系,而实际工程中各回直流系统的控制保护仍基于本回电气量信息,必然无法实现其完全解耦分析,从而增加了准确故障定位的难度。首先利用同塔双回直流线路的相模变换对基于单回线路电气量的模量特征进行详细分析,构造了消去地模分量的新差模分量,并对其特点及参数选择进行了分析。然后根据非故障点的线路两端沿线计算电压在故障时刻附近具有最大差值的特点,定义了非故障点最大电压差值区段,进而提出了一种基于单回直流线路电气量的时域故障测距算法。基于PSCAD/EMTDC对实际同塔双回直流系统的大量仿真测试结果表明:所提算法测距精度高,且不受故障极线、故障位置及过渡电阻的影响。
There exists complicated electromagnetic coupling between different polar lines for double-circuit high-voltage direct current（HVDC）transmission lines on the same tower.In an actual project,the control and protection of each circuit is still based on the single-circuit electrical quantities.Inevitably,it is unable to achieve its complete decoupling,which increases the difficulty in accurate fault location.Firstly,the characteristics of the modulus based on single-circuit quantities are analyzed using the transformation matrix.Based on this,the new differential-mode component,which has eliminated the influence of the earth-mode,is constructed.The characteristics and parameter selection of the new differential-mode component are also given.Then,given the characteristic that the voltage distributions of the non-fault point calculated by the voltage and current measured in both terminals have the largest difference around the fault time,the maximum voltage difference zone of the nonfault point is defined.Further,a fault location method based on single-circuit quantities is proposed.The PSCAD/EMTDC simulation model of real double-circuit HVDC transmission lines on the same tower is constructed with extensive simulation results showing that the proposed method is not only highly accurate,but also unaffected by fault polar lines,fault position and the resistance.
出处
《电力系统自动化》
EI
CSCD
北大核心
2016年第12期172-178,共7页
Automation of Electric Power Systems
基金
国家自然科学基金资助项目(51577072)
中央高校基本科研业务费专项资金资助项目(2013ZZ028)~~
关键词
同塔双回直流线路
故障测距
单回电气量
分布参数线路模型
double-circuit high-voltage direct current（HVDC）transmission lines on same tower
fault location
single-circuit electrical quantities
distributed parameter line model
