考虑光伏无功补偿的多馈入直流受端电网强度分析  

Strength Analysis of Multi-infeed Receiving-end DC Power Grid Considering Photovoltaic Reactive Power Compensation

作　　者：李羽晨 王冠中[1] 张静 周靖皓 叶琳 辛焕海[1] LI Yuchen;WANG Guanzhong;ZHANG Jing;ZHOU Jinghao;YE Lin;XIN Huanhai(College of Electrical Engineering,Zhejiang University,Hangzhou 310027,China;Electric Power Dispatching and Control Center of State Grid Zhejiang Electric Power Co.,Ltd.,Hangzhou 310007,China)

机构地区：[1]浙江大学电气工程学院,浙江省杭州市310027 [2]国网浙江省电力有限公司调度控制中心,浙江省杭州市310007

出　　处：《电力系统自动化》2021年第15期28-35,共8页Automation of Electric Power Systems

摘　　要：具有多馈入直流外受电和新能源集中并网的受端电网稳定运行需要交流系统提供足够的电压支撑强度。有必要研究如何准确量化受端电网强度。文中考虑定性分析和定量评估2个方面,从广义短路比及其临界值变化的角度研究了光伏电站接入对受端电网静态电压稳定裕度的影响。首先,建立系统的准稳态模型,利用光伏电站接入对交流网络雅可比矩阵主导特征值的灵敏度,定性分析了不同控制方式下光伏电站对系统静态电压稳定性的影响;其次,基于模态摄动,给出考虑光伏电站接入后的广义短路比及其临界值的计算方法和评估流程;最后,通过量化光伏电站无功补偿对系统强度的影响,给出光伏电站电压-无功功率下垂控制系数的选择方法。仿真结果验证了所提方法的可行性和有效性。The stable operation of the receiving-end power grid with multi-infeed DC external power and centralized grid connection of new energy requires the AC system to provide sufficient voltage support strength.It is necessary to study how to accurately quantify the receiving-end power grid strength.Considering the qualitative analysis and quantitative evaluation,this paper studies the influence of photovoltaic(PV)power station access on the static voltage stability margin of receiving-end power grid from the perspective of generalized short circuit ratio(gSCR)and its critical value change.Firstly,the quasi steady state model of the system is established,and the influence of PV power stations on the static voltage stability of the system under different control modes is qualitatively analyzed by using the sensitivity of PV power station access to the dominant eigenvalue of AC network Jacobian matrix.Secondly,based on the modal perturbation,the calculation method and evaluation process of the gSCR and its critical value are given.Finally,by quantifying the influence of reactive power compensation of PV power station on system strength,the selection method of voltage-reactive power droop control coefficient is given.Simulation results verify the feasibility and effectiveness of the proposed method.

关 键 词：多馈入直流系统 静态电压稳定 光伏 广义短路比 电网强度 

分 类 号：TM721.1[电气工程—电力系统及自动化] TM615