VFTO下分段层式变压器线圈电位分布研究

摘要

It is very important for transformer insulation design to calculate winding potential distribution of the transformer with subsection and layer winding under VFTO(Very Fast Transient Over-voltage). VFTO generated GIS switchgear switching is very harmful to transformer insulation. In order to accurately simulate the very fast transient process in the winding, a lumped parameter model with single layer winding unit is proposed. The physical model and math formula for the calculation of the inductance,capacitance and resistance parameters are introduced. The consistency between simulation and measurement in an actual transformer winding verifies the correctness of proposed model,which provides the theoretical basis for reasonable transformer winding insulation design.%　　特快速暂态过电压(VFTO)作用下分段层式变压器线圈的电位分布计算对于变压器的绝缘设计是非常重要的。由于GIS中开关投切产生的陡波前过电压对变压器的绝缘危害极大，为了准确计算线圈中的快速暂态过程，提出了一种以单层线圈为单元的集总参数线圈模型，介绍了电感、电容、电阻等参数计算的物理模型和数学公式。实测和计算一台变压器线圈模型电位分布的结果近似一致，说明集总参数线圈模型和计算方法是正确可行的，可以为变压器线圈合理的绝缘设计提供理论依据。