特高压换流站内电压变送器中铁磁材料励磁曲线拟合方法研究

Research on Excitation Curve Fitting Methods of Ferro magnetic Material in Voltage Transformer of UHV Converter Station

摘要:

研究了特高压换流站中由交直流耦合引发的铁磁谐振过电压问题，针对套管末屏测量单元中电压变送器的励磁曲线特性，分析了奇次多项式拟合与正切函数拟合的特点。利用泰勒公式与伯努利函数等数学工具论证了二者的拟合特性具有内在统一性，为铁磁谐振非线性方程的各种解析解和数值提供了理论支撑。

Abstract:

Ferroresonance over － voltage caused by coupling of AC and DC system in ultra － high voltage ( UHV) converter station is studied． Based on the excitation curve in voltage transformer unit，both characteristics of odd order polynomial fitting and tangent function fitting are analyzed and compared． Taylor's formula and Bernoulli function are induced to prove the unity of both fitting methods，which provides a theoretical foundation for analytic solution and numerical solution．