变压器有载分接开关切换试验中负序电流分析  

Analysis of negative current in switching tests for load tap on-load tap-changers of transformers

作　　者：桂勤昌[1] 潘永刚[1] 李献伟[2] 

机构地区：[1]华东电力试验研究院有限公司,上海200437 [2]上海华明电力设备制造有限公司,上海200333

出　　处：《华东电力》2008年第1期96-99,共4页East China Electric Power

摘　　要：变压器有载分接开关切换试验时,将经过单电阻过渡和双电阻过渡状态,由于破坏了调谐回路的谐振条件,将在外回路产生不对称的冲击电流,向电网注入负序电流。现采用谐振法进行分接开关切换试验时,建立了切换过程中单电阻过渡状态和双电阻过渡状态试验回路等值电路,以及回路参数的数学模型,并在不同支撑相电压、级电压、不同试验电流下,计算分析注入电网的负序电流分布特征。根据电网对注入负序电流的限值,分析分接开关试验允许范围。During the switching test for transformer on-load tap-changers, the transformer will experience both singleresistance transition state and double-resistance transition state, which will generate asymmetry rush current in the external circuit due to breaking of the resonance condition of the resonance loop. Consequently, negative current will be injected into the grid. To solve the problem, during the switching test with the resonance method, the test equivalent circuits for the single-resistance transition state and the double-resistance transition state were established, as well as the mathematic model for circuit parameters. The distribution characteristics of the negative current were analyzed un- der different supporting phase voltage, different level voltage, and different test current. The limit value of the negative current putting into the grid was used to analyze the acceptable range for the tap-changer test.

关 键 词：试验变压器 有载分接开关 谐振法 负序电流 

分 类 号：TM403.4[电气工程—电器]