摘要
与传统发电机不同,撬棒保护投入下的双馈风机(DFIG)输出电流中含有较大的与工频接近的转子频分量,而基于工频测量原理的保护算法无法将其滤除,这给新型电力系统中工频保护的定值整定带来了挑战。文中基于撬棒保护投入下DFIG电流的时域表达式,全面分析了影响包络区间的不同因素,并对其进行分类归纳后探讨各因素在包络区间计算中的计及方法,得到了两层式的整体计算流程。在此基础上,提出了撬棒保护投入下考虑多影响因素的DFIG输出电流包络区间计算方法。该方法计及各种可能的故障工况,全面考虑了不同因素对转子频分量的影响,并通过设置离散步长、逐点求解,得到了较为精确的输出电流包络区间。在MATLAB/Simulink平台中进行了DFIG并入无穷大系统仿真。结果表明,文中方法的计算值与仿真值之间误差均较小,验证了所提计算方法的正确性。
Unlike traditional generators,the output current of a doubly-fed induction generator(DFIG)with crowbar protection switched on contains a considerable rotor frequency component close to the power frequency,which cannot be filtered out by protection algorithms based on power frequency measurement principles,posing a challenge to the setting of the power frequency protection in the new power systems.Based on the time-domain expression of the DFIG output current with crowbar protection switched on,this paper comprehensively analyzes the different factors that affect the envelope intervals,explores the calculation method of each factor in the envelope intervals by categorizing and summarizing them,and obtains a two-layer overall calculation process.On this basis,the calculation method for the DFIG current envelope intervals with crowbar protection switched on is proposed.This method takes into account various possible fault conditions,and comprehensively considers the influence of different factors on the rotor frequency component,and obtains a more accurate output current envelope interval by setting discrete steps and solving point by point.The simulation of DFIG integrating the infinity system is carried out on the MATLAB/Simulink platform.The results indicate that the errors between the calculated values of the proposed method and simulated values are relatively small,thus verifying the correctness of the proposed calculation method.
作者
黄琛
沈毅
李银红
HUANG Chen;SHEN Yi;LI Yinhong(School of Electrical and Electronic Engineering,Huazhong University of Science and Technology,Wuhan 430074,China;State Key Laboratory of Advanced Electromagnetic Technology,Wuhan 430074,China)
出处
《电力系统自动化》
北大核心
2025年第3期93-102,共10页
Automation of Electric Power Systems
基金
国家自然科学基金资助项目(52207107)。
关键词
保护定值整定
故障工况
双馈风机(DFIG)
撬棒保护
工频测量
包络区间
protection value setting
fault condition
doubly-fed induction generator(DFIG)
crowbar protection
power frequency measurement
envelope interval
