基于故障数据的线路分布参数时域辨识方法

摘要

The existing frequency domain identification methods using fault records can not identify the transmission lines distributed parameters accurately, so this paper proposes a more accurate method of distributed parameter identification based on time-domain model. The method uses the fault voltages and currents measured at both terminals of the lines and calculates the line parameters by the least squares method in time-domain to avoid the error caused by vector transformation using frequency-domain method. It uses instantaneous symmetrical component method extracting sequence component to identify positive-sequence and zero-sequence parameters respectively in time-domain and uses LOWESS method smoothing fault signal noise to enhance the anti-interference performance of algorithm. The simulation results show that the proposed method can effectively identify the distribution parameters, and has high accuracy in a variety of fault conditions.%　　针对目前基于故障数据的频域辨识方法难以精确辨识线路分布参数的问题，基于线路分布参数时域模型，提出了一种更精确的分布参数辨识方法。该方法利用线路两端采集的故障电压电流信号，在时域内通过最小二乘搜索法辨识得到线路参数，避免了频域法向量转换导致的误差。并采用瞬时对称分量法提取序分量，实现时域内分别对正序和零序参数的辨识；采用 LOWESS 方法平滑故障信号中的噪声，以提高算法的抗干扰性。仿真算例的结果表明，所提出的方法能够准确辨识线路的分布参数，并且对各种故障条件均具有良好的适应性。