配电线路阻抗在线虚拟量测研究

Research on on-line virtual measurement of impedance for distribution line

为了获得准确的配电线路阻抗参数,提出了一种配电线路阻抗在线虚拟量测方法。根据线路段首、末端采集到的大量电压、电流信息,建立线路段的电压降线性等效计算模型,采用回归分析法或平均值解方程法等数学方法分析、计算出电压降线性等效计算模型的系数,末端电流对应的系数即是该线路段的阻抗,从而实现线路参数的在线辨识。利用该方法对一条实际运行的配电线路进行建模与计算,并与线路实际阻抗进行了比较分析。计算结果表明,基于电压降线性等效计算模型的配电线路阻抗在线虚拟量测方法是有效和实用的,并具有计算速度快,实时性好的优点。

To obtain the impedance parameters of distribution line accurately, a method for on-line virtual measurement of impedance for distribution line is proposed. According to three-phase current and voltage information collected from the head and end of the line, a linear equivalent calculative model of voltage drop is built. Then by use of mathematical methods, such as regression analysis method and solving equation groups utilizing average value, the method analyzes and calculates the coefficients of the voltage drop linear equivalent calculative model. The coefficient corresponding to terminal current is the impedance of the line. This is the calculation process of the parameters of the distribution line. The method is used to calculate the impedance of a running distribution line, and the calculation results and the actual impedance are compared and analyzed. The analysis results show that the on-line virtual measurement of impedance based on the voltage drop linear equivalent calculative model is feasible and effective, and this method has the advantages of fast computation and good real-time performance. This work is supported by National Natural Science Foundation of China （No. 51177152）.