Symmetrical and unsymmetrical voltage sag effects on three-phase transformers
Symmetrical and unsymmetrical voltage sag effects on three-phase transformers
复制标题
对称和不对称电压暂降对三相变压器的影响
DOI：
10.1109/tpwrd.2004.833910
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发表时间：
2005
影响因子：
4.4
通讯作者：
L. Guasch
中科院分区：
文献类型：
--
作者：
J. Pedra;L. Sainz;F. Córcoles;L. Guasch
本文研究了对称和不对称电压暂降对三相三腿变压器的影响。变压器模型包括饱和度，参数是通过实验测量获得的。研究表明，当电压恢复时，电压跌落会导致变压器饱和。这种饱和产生的浪涌电流类似于变压器通电期间产生的浪涌电流。该研究考虑到电压恢复瞬间只能取离散值，因为故障清除是在自然电流零点产生的。本文还研究了凹陷类型、持续时间、深度和故障电流角度对励磁涌流峰值的影响。电流峰值对凹陷持续时间具有周期性依赖性，并且对深度具有线性依赖性。不对称凹陷会导致与对称凹陷一样高的电流峰值。
This paper studies the effects of symmetrical and unsymmetrical voltage sags on three-phase three-legged transformers. The transformer model includes saturation and the parameters have been obtained from experimental measurements. The study shows that sags can produce transformer saturation when voltage recovers. This saturation produces an inrush current that is similar to the inrush current produced during the transformer energizing. The study takes into account that the voltage recovery instant can take only discrete values, since the fault-clearing is produced in the natural current zeroes. The paper also studies the influence of the sag type, duration, depth and fault current angle on the inrush current peak value. The current peak has a periodical dependence on sag duration, and a linear dependence on depth. Unsymmetrical sags can result in current peaks as high as those of symmetrical sags.