发电厂主变空载损耗计量不一致问题分析

Analysis of power plant transformer no-load loss measuring inconsistency

针对发电厂单元接线机组在主变空载运行特殊情况下不同电能表计量不一致的事件进行现场调查和原因分析。结果表明,电流互感器在一次电流低于有效测量范围的情况下有较大的测量失真,二次电流波形含有较强非周期分量和高次谐波分量,而不同厂家电能表的谐波计量功能不一致导致计量的电量相差较大。

The reason of transformer no-load loss measuring inconsistency in mode of unit connection is surveyed and analysed in the paper. The analysis result shows that the current transformer measuring result is distorted badly in the case that the current is less than effective measuring range. The current of electrical second side contains non-periodic component and highorder harmonic. The principles of harmonic measuring are different between various electric energy meter,and it brings the measuring inconsistency.