发电机组静止励磁系统励磁电流基值分析

针对励磁系统建模时由于励磁电流测量误差大,引起发电机空载特性测量稳定性差,励磁电流基值整定困难的问题,本文通过对励磁电流测量位置和测量方式的分析对比,结合建模时的现场条件,提出采用直流侧分流器法,采样频率30kHz以上,时间常数0.2~0.3s滤波的方法测量励磁电流。最后,将该方法应用于630MW机组励磁电流基值整定,并利用电力系统仿真软件验证。结果表明,该方法能满足工程化应用要求。

Analysis of Excitation Current Base Value of Static Excitation System of Generator

For the problems of the generator no-load characteristics of poor measurement stability and excitation current base value difficultly setting, which are caused by excitation current measurement error in the excitation system modeling, the paper proposes a method to measure the excitation current by using the DC-side shunt method, and the sampling frequency is more than 30kHz and filter time constant is 0.2~0.3s through the analysis and comparison of the test site conditions, and excitation current measurement position and measurement mode. Finally, the method is applied to the excitation current base value setting of the 630MW unit, and the measured results are verified by the power system simulation software. The results show that the method can meet the engineering application requirements.