东北电网500kV人工三相接地短路试验总结

500kV Man-Made Three-Phase Earthing Short Circuit Experiment in Northeast Power Grid

东北与华北联网后东北电网动态特性明显恶化、稳定水平大幅度下降,不同发电机和负荷模型对稳定计算的结果影响很大。虽然采取了计及励磁系统动态行为的详细发电机模型的仿真方法、在东北电网重要发电机组上加装电力系统稳定器(power system stabilizer,PSS)等措施,但PSS参数整定的合理性及整体匹配效果无法得到有效验证,选择电力系统模型尤其是负荷模型还缺乏足够科学依据,对所选模型与电网运行实际的贴近程度也很难做出准确的定量甚至定性的分析。为此东北电网有限公司提出了大区电网联网模式下东北电网稳定水平研究的工作思路,并于2004年3月25日和2005年3月29日在500kV电压等级运行电网上分别实施了2次人工三相完全金属性接地短路试验。试验达到了预期效果,表明根据大扰动试验的实测数据,进行电网负荷模型的校核和修正,建立适用于我国电网的负荷模型的技术路线和研究方法在工程上是可行的和有效的。

Since the interconnecfion of Northeast Power Grid with North China Power Grid, the dynamic properties of Northeast Power Grid were evidently worsened and its stability level was greatly decreased, in addition, different models of generators and loads significantly affected the results of stability calculation. Although the measures such as the simulation method with detailed generator model in which the dynamic behavior of exciting system is taken into account and installing power system stabilizers （PSSs） in main generators of Northeast Power Grid were adopted, it was still unable to effectively verify the reasonableness of parameter setting of PSS as well as its integrated matching result, and there was not enough scientific foundation for the selection of power grid model, especially load models. Moreover, it was hard to make accurate quantitative analysis, even though the qualitative analysis, on the close extent of selected models to actual operation of power grid. For this reason, the Northeast Power Grid Corp., Ltd., proposed the thinking of researching stability level of Northeast Power Grid under the interconnection mode of areal power grids, and on March 25, 2004 ＆ March 29, 2005, two man-made three-phase metallic ground short-circuit experiments were implemented in 500kV power grid being operated respectively and desired results were achieved. Experiment results show that based on the measured data from large disturbance tests, it is feasible and effective in practice to verify and modify load models as well as estabfish the research method and technical line suitable to load models of power grids in China.