基于虚功率原理的发电机转子匝间短路诊断方法研究  

Research on Diagnosis Method of Inter-Turn Short Circuit of Generator Rotors Based on the Principle of Virtual Power

作　　者：张树铭 ZHANG Shu-ming(East China Electric Power Test and Research Institute,China Datang Corporation Science and Technology General Research Institude Co.,Ltd,Hefei 230088,China)

机构地区：[1]中国大唐集团科学技术研究总院有限公司华东电力试验研究院,安徽合肥230088

出　　处：《电工电气》2022年第12期63-68,共6页Electrotechnics Electric

摘　　要：对于大型汽轮发电机,可以拟合分析空载电动势和励磁电流的关系,通过比较实际励磁电流和拟合得出的理论励磁电流来判断转子绕组是否存在匝间短路。以发电机SIS数据为基础,针对纯线性拟合模型精度较差的问题,提出了基于无功功率分段拟合的模型拟合方法,得到的拟合函数是励磁电流关于无功功率和空载电动势的二元函数,有效提升了拟合模型的精度,提高了汽轮发电机转子绕组匝间短路故障诊断的灵敏性和可靠性。该方法在工程实践中成功验证了某600 MW发电机的转子匝间绝缘故障。It is able to make fitting analysis of the relations between unloaded electromotive force and excitation current for large turbo-generators.The paper compares the actual excitation current with the theoretical excitation current gotten from fitting experiments to judge whether there is inter-turn short circuit of rotor winding or not.The paper,based on the SIS data of generators,to solve the problem of low accuracy of pure linear fitting model puts forward the model fitting method from the perspective of powerless power piecewise fitting.The fitting function obtained from this method is the function of two variables which are powerless power and unloaded electromotive force,increasing the accuracy of fitting model and improving the sensitivity and reliability of diagnosing rotor inter-turn short circuit fault.According to the engineering practice,the method successfully verifies the rotor inter-turn insulation fault of a 600 MW generator.

关 键 词：转子匝间短路 线性拟合 绝缘故障 无功功率 

分 类 号：TM311[电气工程—电机]