一种在线计算系统阻抗的新方法

变电站母线处的系统戴维南等值电路是电力系统规划与运行的重要参数。本文提出一种利用各变电站母线的稳态电压电流测量值,在线估计正序和零序戴维南等值电路阻抗的新方法。此方法可应用于各种负荷工况,不向系统注入扰动信号,且该方法不需要同步采样数据,因此不受系统频率变化的影响。仿真分析和现场测量数据表明此方法可准确实现系统阻抗参数的在线估计。

A New Method of System Impedance Online Computation

The Thevenin impedance seen at a substation bus is an important parameter for power system planning and operation. This paper presents an algorithm for online monitoring of positive and zero sequence Thevenin impedance parameters for the power system. The proposed algorithm uses the steady state measurements taken at the substation bus for calculations. The advantage of the method is the capability of operating under normal conditions without imposing any disturbance to the system. The method does not require synchronized measurements; therefore, the variation of system frequency does not affect the performance of the algorithm. The method has been verified through several real field measurements.