中文摘要：

采用基于分段函数拟合磁化曲线的改进方法,考虑不饱和励磁的非线性,求解三维棱边有限元磁场.采用时域场路耦合方法计算变压器直流偏磁时的瞬态电流和动态电感,分析其变化规律和对应关系.讨论不同磁化曲线拟合方法计算直流偏磁的效果,研究不饱和励磁非线性对耦合参数和伏安特性的影响.通过与实验数据对比,分析所提方法的误差,验证分段拟合方法具有更高的准确性.

英文摘要：

An improved method of saturated magnetization curve fitting based on piecewise function is proposed to solve three-dimensional magnetic field with edge finite element,which considers the nonlinearity of unsaturated magnetization.The transient current and the dynamic inductance of single-phase transformer with DC-bias are computed based on the time-domain field-circuit coupling model,and their variation rule and corresponding relationship are analyzed.Different fitting methods for DC-bias computation are discussed and the impact of the nonlinearity of unsaturated magnetization on the coupling parameters and volt-ampere characteristics is analyzed.The accuracy and validity of the proposed method are verified by the comparison with the experimental data.