基于时间-电流曲线的变压器剩磁检测方法研究

Study on transformer residual flux detection method based on the time-current curve

文章从铁磁材料固有的磁滞现象角度分析了变压器剩磁产生的原因,提出了基于时间-电流曲线的变压器剩磁检测的方法。通过对电力变压器原边加载幅值相同的正负恒压源对变压器进行充放电,得到变压器的"时间-电流"曲线以判定变压器中有无剩磁及剩磁的极性。仿真及实验结果表明,基于时间-电流曲线的剩磁检测方法能够准确测量变压器是否存在剩磁及剩磁的极性,为变压器合理投切及抑制励磁涌流提供了参考依据。

This paper analyzes the reason of transformer residual flux resulting from the inherent hysteresis in the fer- romagnetic material, and presents a novel method to detect transformer residual flux based on the time-current curve. Through the power transformer primary loads the same amplitude positive and negative voltage source to charge and discharge, thus, a ＂time-current＂ curve is obtained to determine whether the transformer has residual flux and polarity of residual flux. MATLAB simulation and experiment verify that the transformer residual flux detection method based on the time-current curve can accurately measure whether the transformer has？ residual flux and polarity of residual flux, which provides a reference for the transformer reasonable switching and eliminating the inrush current.