单相变压器匝间短路电磁特性研究  

Study on Electromagnetic Characteristics of Interturn Short Circuit of Single-phase Transformer

作　　者：潘超[1] 石文鑫 孟涛 PAN Chao;SHI Wenxin;MENG Tao(Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology,Ministry of Education,Northeast Electric Power University,Jilin 132012,China;Electric Power Research Institute,State Grid Jilin Electric Power Co.,Ltd.,Changchun 130021,China)

机构地区：[1]现代电力系统仿真控制与绿色电能新技术教育部重点实验室(东北电力大学),吉林132012 [2]国网吉林省电力有限公司电力科学研究院,长春130021

出　　处：《高电压技术》2020年第5期1839-1852,共14页High Voltage Engineering

基　　金：国家自然科学基金(51507027);吉林省自然科学基金(2018JLSF-9)。

摘　　要：针对变压器匝间短路导致的内部电流剧增与励磁问题,研究变压器匝间短路时电流、主磁通及漏磁通特性。建立变压器匝间短路模式下的时域微分电路方程,基于能量扰动原理计算绕组电流,仿真模拟原、副边绕组不同匝间短路位置、不同短路比例及不同负载下的绕组电流和铁芯磁通及绕组漏磁通。研究电流及磁通变化规律,并分析其主要影响因素,利用铁芯磁通表征变压器励磁饱状态。结果表明,变压器额定运行原边绕组发生匝间短路(匝数比例为0~10%)时,原边端口电流增大到0~4倍,短路电流约增为正常原边端口电流的23倍;副边绕组发生同比例匝间短路时,原边端口电流增大到0~3倍,短路绕组电流约增为正常副边端口电流的14倍。同时,铁芯励磁局部饱和,绕组漏磁增大;伴随负载率降低,铁芯励磁饱和程度加深;短路比例升高,绕组漏磁通增大。搭建变压器匝间短路试验平台,量测相关电流参数,并与仿真所得电流数据比对,验证所得结论正确性,从而为变压器匝间短路的保护设计与整定提供依据。Aiming at the problem of internal current surge and excitation saturation caused by transformer interturn short circuit,we investigated the characteristics of current,magnetic flux and the working principle of transformer interturn short circuit.The time domain differential circuit equation of transformer interturn short circuit mode is established,and the winding current is calculated based on the principle of energy disturbance.The winding current,core flux and leakage flux of the primary and secondary windings with different interturn short circuit ratios and different loads are simulated,respectively.The variation law of current and flux is studied,the main factors affecting the change are analyzed,and the core flux is used to characterize transformer excitation saturation state.The results show that when inter-turn short circuit occurs in primary winding(the turn ratio is 0~10%)of rated operation of transformer,the current of primary side port increases to 0~4.0 times,the short-circuit current suddenly increases to 23 times of the current of primary side port,and the current of secondary side port almost remains unchanged.When inter-turn short circuit occurs in the secondary side winding,the current of primary side port increases to 0~3.0 times,and the short-circuit current suddenly increases to 14 times of the current of secondary side port.At the same time,the core excitation is locally saturated.The magnetic flux leakage of winding increases.When the load ratio decreases,the saturation degree of core excitation deepens.When the short circuit ratio increases,the leakage flux of winding will increase.A test platform for transformer inter-turn short circuit is built to measure current parameters and to verify the correctness of the conclusions by comparing with the current data obtained by simulation,thus providing a basis for the protection design and setting of transformer inter-turn short fault.

关 键 词：匝间短路 原副边绕组 电磁耦合 绕组电流 主磁通 励磁饱和 

分 类 号：TM411.1[电气工程—电器]