基于快速相量提取算法的距离保护方案

A Distance Protection Scheme Based on Fast Phasor Extraction Algorithm

傅立叶算法和最小二乘法在传统距离保护中得到了广泛应用,但2种算法均存在原理上的固有缺陷,提出了一种新的快速相量算法。该算法基于最小二乘矩阵束的原理,对补偿矩阵进行降阶处理,缩减了计算量,提高了计算效率。该方案首先利用快速相量算法提取工频分量,然后基于输电线路RL模型,利用工频测距方程,进行区内、外故障位置的判别。该方案采用的是单端电气量计算,大大提高了保护动作的灵敏性。理论分析和仿真结果均表明,该保护方案具有计算量小,精度高、受数据窗影响小等特点,具有一定的实用价值。

In view of inherent defects in Fourier algorithm and least square algorithm,which are widely applied in traditional distance protection,a novel fast phasor extraction algorithm is proposed.Based on the principle of least square matrix pencil,the order of compensation matrix is reduced,thus the calculation amount is decreased and the calculation efficiency is improved.Firstly,the power frequencyphasors are extracted by the proposed fast phasor extraction algorithm;secondly,based on RL model of transmission line and power frequency fault location equation is utilized to judge whether the fault position is inside or outside the protection zone.In the proposed distance protection scheme,only single end electric quantities are utilized,thus the sensitivity of the protection is obviously improved.Results of both theoretical analysis and simulation show that the proposed distance protection scheme possesses such advantages as small calculation amount,high accuracy,slightly affected by data window and so on,therefore it is practicable.