变压器空载电流谐波低频测量方法研究  

Study of No-load Current Harmonics Measurement of Transformers Using LowFrequency Method

作　　者：刘鑫[1] 梁仕斌 刘涛 邱纯阳 邹博[1] 

机构地区：[1]云南电网公司研究生工作站,昆明650217 [2]云南电力技术有限责任公司,昆明650217 [3]云南电力试验研究院(集团)有限公司,昆明650217

出　　处：《云南电力技术》2017年第2期133-138,共6页Yunnan Electric Power

摘　　要：变压器空载电流谐波幅值及构成可以检查铁心的饱和程度和判断是否有匝间故障。变压器出厂试验时通常采用容量较大的工频电源进行空载电流谐波测量。为了减小试验电源容量,提出了一种采用低频电源代替工频电源进行变压器空载电流谐波测量的低频测量法。该方法通过施加两个低频率的电压测量低频下的涡流电流和空载电流谐波幅值,再根据对涡流电流的补偿计算折算至工频下的空载电流各次谐波含量和总谐波含量。并对单相变压器进行仿真和试验验证,采用15Hz的折算的结果与工频50Hz实测结果的空载电流各次谐波含量K(k)和总谐波含量THDi误差均小于1%。结果表明,本方法折算准确度高,而且能减小试验电源容量。The amplitude and composition of transformers no-load current harmonics can be used to examine the saturation degree and detect the inter-turn faults. Generally, a large capacity of industrial-frequency （IF） power supply is needed to measure the no-load current harmonics content for factory test. In order to reduce the capacity of testing power supply, a low frequency method which use a low-frequency power supply to replace IF power supply for no-load current harmonics content measurement of transformers was proposed in this paper. In this method, the eddy current and no-load current harmonics were first obtained by applying two low frequencies voltages. The converted current harmonics content and total harmonics distortion （THDi） under IF were then calculated based on eddy current compensation. In addition, experiments and simulations were conducted on the single phase power transformer, comparing conversion results which using 15Hz with directly measured results under IF, the measurement error of harmonics content and THDi are both below 1%. These results show that this method possesses high conversion accuracy and can reduce the capacity of testing power supply significantly.

关 键 词：变压器 空载电流谐波 铁心损耗 低频法 涡流电流 

分 类 号：TM41[电气工程—电器]