地磁暴影响下特高压交流电网电压稳定性量化评估方法  

Quantitative Evaluation Method of Voltage Stability of UHV AC Power Network under Geomagnetic Storm

作　　者：辛文凯 王泽忠[1] 刘春明[2] 李宇妍 Xin Wenkai;Wang Zezhong;Liu Chunming;Li Yuyan(Beijing Key Laboratory of High Voltage and EMC North China Electric Power University,Beijing 102206 China;School of Electrical and Electronic Engineering North China Electric Power University,Beijing 102206 China)

机构地区：[1]高电压与电磁兼容北京市重点实验室(华北电力大学),北京102206 [2]华北电力大学电气与电子工程学院,北京102206

出　　处：《电工技术学报》2023年第21期5771-5780,共10页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金资助项目(52177081)。

摘　　要：地磁暴时,地磁感应电流(GIC)流经变压器会产生大量无功损耗,引起电网电压波动。随着我国特高压交流电网规模的扩大,地磁暴给特高压交流电网电压稳定带来的威胁越来越大。为了准确评估地磁暴对电力系统电压稳定的影响,该文建立了适用于地磁暴期间衍生无功扰动影响电压稳定的分析模型,通过对线路的等效变换,适应于多电压等级电网的多进线节点电压稳定分析。该文将地磁暴造成的无功扰动加入电压稳定分析模型得出地磁暴影响下的PV曲线解析式,并提出电压失稳指标,避免了连续潮流法预测校正过程中步长难以准确选取、计算复杂等问题,便于确定电网遭受地磁暴侵害时的电压稳定薄弱点和负荷裕度,并通过规划的华东特高压交流电网算例对该方法的有效性进行了验证。Geomagnetic storm is a low probability and high risk natural disaster that threatens the security of power grid.During a geomagnetic storm,an induced electric field is generated on the ground surface.Under its action,geomagnetic induced currents will be generated in the circuit formed by the transmission line,the earth and the neutral point of the transformer.When GIC flows through the transformer,it will cause saturation of the core and consume a large amount of reactive power.This increase in reactive power loss(GIC-Q)is linear with GIC flowing through the neutral point of the transformer,which is usually calculated by the k-value method.GIC-Q will cause voltage fluctuation of the power grid.With the expansion of the scale of UHV AC power grid in China,geomagnetic storms are increasingly threatening the voltage stability of UHV AC power grid.In order to accurately evaluate the impact of geomagnetic storms on voltage stability of power systems, this paper establishes an analysis model applicable to the influence of reactive power disturbances derived during geomagnetic storms on voltage stability. Through equivalent transformation of lines, it is suitable for the analysis of voltage stability of multi input line nodes in multi voltage level power networks. Then, the voltage instability index LGIC is proposed through the voltage stability analysis model, which avoids the problems of difficult to accurately select the step size and complex calculation when calculating the voltage collapse point by the conventional continuous power flow method, and makes it easy to determine the weak point of voltage stability and the load margin when the power grid is attacked by geomagnetic storms.This index can indicate the distance between the current operating point and the voltage collapse point during land acquisition magnetic storm. The closer the LGIC is to 1, the closer the node operating point is to the voltage collapse point. This index has the advantages of less information, simple calculation, clear physical meaning a

关 键 词：地磁暴 电压稳定 负荷裕度 评估指标 无功扰动 

分 类 号：TM712[电气工程—电力系统及自动化]