计及风光相位特性和机-网间元件的短路电流计算方法  

A short-circuit current calculation method considering phase characteristics of wind power and photovoltaic and components between new energy units and grid

作　　者：乔立 黄梓欣 章谋成 魏繁荣[2] 赵红生 刘巨 QIAO Li;HUANG Zixin;ZHANG Moucheng;WEI Fanrong;ZHAO Hongsheng;LIU Ju(State Grid Hubei Electric Power Co.,Ltd.Economic Research Institute,Wuhan 430074,China;State Key Laboratory of Advanced Electromagnetic Engineering and Technology(Huazhong University of Science and Technology),Wuhan 430074,China;College of Electrical Engineering&New Energy,China Three Gorges University,Yichang 443002,China)

机构地区：[1]国网湖北省电力有限公司经济技术研究院,湖北武汉430074 [2]强电磁工程与新技术国家重点实验室(华中科技大学),湖北武汉430074 [3]三峡大学电气与新能源学院,湖北宜昌443002

出　　处：《电力工程技术》2023年第2期241-249,共9页Electric Power Engineering Technology

基　　金：国家自然科学基金资助项目(52107095)。

摘　　要：以风电和光伏为代表的新能源机组大量接入电网使得短路电流的精确计算校核变得困难。针对最新研究中构建新能源并网点短路电流映射模型时,未考虑相位映射及未计及箱变、集电线路、主变及送出线路等机端到并网点间电气元件(机-网间元件)影响的理论缺陷,文中提出一种计及新能源相位特性和机-网间元件影响的改进工程化电网短路电流计算方法。首先,结合国家运行规程对新能源机端电压-短路电流相位映射进行有补充意义的理论建模。其次,对该模型进行工程化处理,并提出一种将所得映射逆推至并网点的迭代计算方法。继而,将工程化后的并网点短路电流幅相映射模型应用到现有局部迭代计算中,得到改进的计算方法。最后,在PSCAD仿真软件中搭建新能源并网模型,验证了新能源机端电压-短路电流理论幅相映射的准确性、机端映射模型逆推至并网点的迭代计算理论有效性;在此基础上,在IEEE 39节点系统中对所得映射模型进行实验验证。结果表明所提改进计算方法能在一定程度上提升短路电流计算精度。A large number of new energy units represented by wind power and photovoltaics are connected to the grid,making accurate calculation and verification of short-circuit current difficult.Given the phase mapping and the influence of electrical components(components between new energy units and grid)from the unit port to the grid-connected point,such as box transformer,collecting line,main transformer and transmission line are not considered when constructing the short-circuit current mapping model of new energy grid-connected point in the latest researches,an improved engineering grid short-circuit current calculation method that takes into account the phase characteristics of new energy sources and the influence of components between new energy units and grid is proposed.Firstly,combined with the national operation regulations,a supplementary theoretical modeling of the port voltage to short-circuit current phase mapping of new energy units is proposed.Secondly,the model is processed by engineering,and an iterative calculation method is proposed to extrapolate the obtained mapping back to the point of coupling.Then,the engineered short-circuit current amplitude-phase mapping model is applied to the existing local iterative calculation to obtain an improved calculation method.Finally,the new energy grid-connected model is built in the PSCAD simulation software to verify the accuracy of amplitude-phase mapping theory of new energy unit port voltage to short-circuit current and the effectiveness of iterative calculation theory of extra polating the unit port mapping model back to the point of coupling.On this basis,the mapping model is further verified by experiments in IEEE 39-node system.The results show that the proposed improved calculation method can improve the calculation accuracy of short-circuit current to a certain extent.

关 键 词：工程迭代 风光机组 新能源 短路电流计算 精度提升 机-网间元件 幅相映射 

分 类 号：TM744[电气工程—电力系统及自动化]