基于固有频率的高压直流输电线路故障测距

Fault-Location Method for HVDC Transmission Lines Based on Natural Frequency

行波波头难以标定是影响行波测距精度的主要因素,而基于固有频率的故障测距无需标定波头。在分析高压直流输电线路行波波速特点的基础上,提出基于固有频率的新型故障测距方法。利用线路两侧的故障数据,无需线路参数及计算行波波速,即可进行准确故障测距;采用后向预测Prony算法提取所需的固有频率后,利用模糊聚类算法对其进行筛选和优化,既提高了测距方法的快速性和准确性,也减少了测距过程中人员的介入,提高了测距自动化水平。PSCAD和Matlab联合仿真结果表明,该方法可实现快速、准确测量高压直流输电线路故障。

The main limitation of traveling wave fault-location method is it’s difficult to calibrate the wave correctly, but for the fault- location method based on natural frequency, the calibration is not required. Considering the characteristics of the wave speed of HVDC transmission lines, a novel fault-location method based on natural frequency is proposed, which does not require line parameters and the calculation of travaling wave speed, but analyzes the failure data of the line to get the accurate fault distance easily. The backward Prony algorithm is employed to extract the required natural frequency, which will be screened and optimized with the fuzzy clustering algorithm then. So that the rapidity and accuracy of the method will be improvedand the number of personnel involving the locating process will be reduced, thus the level of locating automation will be improved. With the combination simulations by PSCAD and Matlab, it has showed that the rapid and accurate fault-location of HVDC transmission lines can be achieved with the proposed method.