摘要
利用电压相量轨迹信息解析电网失步振荡中心分布特性并实时预判解列断面,能够为主动解列控制提供决策依据。首先针对两机失步模型,证明了沿线各节点的电压相量轨迹是圆,其圆心坐标、半径大小与两侧电势及节点位置有关,依据失步振荡中心的电压过零这一特征,推导出失步振荡中心分布特性是圆或直线的解析方程;其次,针对理想两群摇摆,提出了无需等值参数辨识的失步振荡中心精准定位方法,针对实际电网环境下的失步振荡,利用失步振荡中心所在线路端点的电压相量轨迹与坐标原点的位置关系,构建失步振荡中心所在线路的预判指标,指标存在固定临界值零;最后,提出了失步解列断面预判方法,仅依据线路端点量测即可实现实时预判。500kV两机系统、IEEE-118节点系统和实际交直流混联电网算例验证了方法的有效性,方法计算简单、适用性强、时效性好,具有较高的工程应用价值。
Using the information of voltage phase trajectory to analyze the distribution characteristic of out-of-step oscillation center and predict the splitting section in the real time provides the decision-making basis for the power grid dispatchers. Firstly, for a double machine out-of-step model, it is proved that the voltage phase trajectory of each bus along the line is a circle, whose center coordinate and radius are related to the voltage amplitudes of both sides and the position of the bus. Based on the feature of voltage zero-crossing of the out-of-step oscillation center, the analytical equation to decide whether the distribution characteristic of the out-of-step oscillation center is a circle or a straight line is derived. Then an accurate locating method of the out-of-step oscillation center without the equivalent parameter identification is proposed for the ideal two-group swinging. For the out-of-step oscillation in an actual environment, according to the relationship between the voltage phase trajectory and the original point, a predictive indicator of the line where the out-of-step oscillation center is located is constructed, and the indicator has a fixed threshold zero. Finally, a method of predicting the splitting section is proposed, which realizes the real-time prediction based only on the measured data of the transmission line terminal. The proposed methods are validated using the 500k V double machine system, the IEEE-118 system and the HVDC and AC hybrid power grid. The proposed methods have a high engineering application value and advantages of simple calculation, strong adaptability, good effectiveness.
作者
李宗翰
孙华东
徐式蕴
赵兵
郑超
LI Zonghan;SUN Huadong;XU Shiyun;ZHAO Bing;ZHENG Chao(State Key Laboratory of Power Grid Safety and Energy Conservation(China Electric Power Research Institute),Haidian District,Beijing 100192,China)
出处
《电网技术》
EI
CSCD
北大核心
2023年第3期1098-1106,共9页
Power System Technology
基金
国家重点研发计划项目(2021YFB2400800)。
关键词
电压相量轨迹
失步振荡中心
特性解析
预判指标
解列断面
voltage phase trajectory
out-of-step oscillation center
characteristic analysis
prediction indicator
splitting section
