电压互感器励磁特性曲线拟合的复合解法  

Comprehensive solving method for the fitting of electromagnetic PT excitation characteristic

作　　者：丛伟[1] 孙允[1] 路庆东[1] 哈恒旭[2] 

机构地区：[1]电网智能化调度与控制教育部重点实验室(山东大学),山东济南250061 [2]山东理工大学电气与电子工程学院,山东淄博255049

出　　处：《电力系统保护与控制》2013年第12期60-64,共5页Power System Protection and Control

摘　　要：电磁式PT铁芯的磁通-电流特性曲线通常基于试验测得的伏安特性数据,对待拟合参数进行最小二乘估计获得。由于试验样本数据较多,采用传统的牛顿法求解存在雅克比矩阵规模较大、受初始值影响较大、迭代计算可能无法收敛等问题。提出一种基于一般多项式和正交函数系的待拟合参数复合求解方法,使雅克比矩阵规模仅与待拟合参数的数量有关,与试验样本数据的数量无关,可有效控制求解迭代过程中雅克比矩阵的规模,从而提高了计算效率,保证了迭代的收敛性,使整个计算过程更加稳定。算例仿真验证了该复合求解方法能够简化计算过程,且具有较高的拟合精度,在试验数据量较多的情况下更能突出其优越性。The flux-current characteristic curve of electromagnetic PT is usually obtained by estimating the fitting parameters based on the Least Square method and experimental U - I characteristic data. When the equation set is solved with traditional Newton method, the Jacobian matrix has a larger scale and is badly affected by the initial value of fitting parameters due to large amount of experimental data. The iteration is probably not convergent. A comprehensive fitting parameters＇ solving method based on the combination of the general polynomial and orthogonal function system is presented. This method makes the scale of Jacobian matrix downsized and confined by the number of fitting parameters rather than that of experimental data. Therefore, the calculation efficiency is enhanced and the convergence of iteration is guaranteed. And the whole computational process is more stable. Simulation verifies that this method can simplify the overall calculation and has higher fitting accuracy. In case of large amount of experimental data, the superiority of this method can be better projected.

关 键 词：电磁式PT 励磁特性曲线 拟合 正交函数系 复合解法 

分 类 号：TM451[电气工程—电器]