风火打捆送出系统动态安全域边界线性近似方法  

A Linear Approximation Method of Dynamic Security Region of Wind-Thermal-Bundled Sending System

作　　者：刘瑞宽 陈磊[1] 闵勇[1] 侯凯元 夏德明 周莹 赵宇民 贲驰 LIU Ruikuan;CHEN Lei;MIN Yong;HOU Kaiyuan;XIA Deming;ZHOU Ying;ZHAO Yumin;BEN Chi(State Key Laboratory of Control and Simulation of Power Systems and Generation Equipments（Department of Electrical Engineering,Tsinghua University）,Haidian District,Beijing 100084,China;Northeast China Branch of State Grid Corporation of China,Shenyang 110181,Liaoning Province,China)

机构地区：[1]电力系统及发电设备控制和仿真国家重点实验室(清华大学电机系),北京市海淀区100084 [2]国家电网有限公司东北分部,辽宁省沈阳市110181

出　　处：《电网技术》2018年第10期3211-3218,共8页Power System Technology

基　　金：国家重点研发计划项目(2017YFB0902000);国家自然科学基金项目(51377002)~~

摘　　要：采用电力电子接口的风力发电机动态特性与同步机差异很大,传统的动态安全域（dynamic security region,DSR）边界解析法主要针对电源为同步机的系统,不适用于风电接入系统。基于能量裕度对电源出力的灵敏度,提出了一种风火打捆送出系统DSR边界线性近似的解析方法。建立了适用于机理分析的风火打捆送出系统动态模型。分析了风火打捆送出系统DSR边界的性质,包含暂态功角失稳和暂态电压失稳两个不同的组成部分,分别有不同的线性近似表达式。风电渗透率低时系统失稳模式为暂态功角失稳,DSR边界线性近似的推导过程和传统方法一致。风电渗透率高时系统稳定域边界包含奇异面,失稳模式为暂态电压失稳,基于系统临界稳定时的相切条件推导了临界能量,获得能量裕度对电源出力的灵敏度,并求解DSR边界的线性近似表达式。综合两部分边界获得了完整的DSR边界线性近似。与逐点时域仿真的结果进行了对比,结果验证了上述方法的有效性。Dynamic characteristics of power-electronic interfaced wind turbines are quite different from those of synchronous machines. Traditional analytic method of dynamic security region（DSR） boundary is mainly aimed at the power grid with synchronous machines, and not suitable for wind power access system. In this paper, based on sensitivity analysis of energy margin to power supply, an analytic method for linear approximation of DSR boundary of wind-thermalbundled sending system is proposed. The dynamic model of wind-thermal-bundled sending system suitable for mechanism research is established. By analyzing the properties of DSR boundary of wind-thermal-bundled sending system, the boundary consists of two parts, transient angle instability and transient voltage instability, corresponding to different linear approximate expressions. For low penetration case of wind power, instability mode of the system is transient angle instability, and derivation of linear approximation of DSR boundary is identical with traditional method. For high penetration case of wind power, stability boundary contains singular surface, instability mode of the system is transient voltage instability, and tangent condition for determining transient critical stability is applied to solution of critical energy, and then, sensitivity of energy margin to power supply is derived. Thus the linear approximate expressions of DSR boundary is acquired. A complete linear approximation of the DSR boundary is obtained by synthesizing the two parts of the boundary. By comparing with the results of point-by-point time-domain simulation method, validity of the proposed method is verified.

关 键 词：风火打捆 灵敏度分析 动态安全域 奇异面 电压失稳 

分 类 号：TM712[电气工程—电力系统及自动化]