应用互补变分原理计算大型变压器的短路电抗——兼论恒定磁场的T-Ω方法

Calculation of Short-Clrcuit Impedance of Large Transformer by Means of Complementary Variational Principles——A New T-Ω Algorithm of Magnetostatic Field Computation

本文首次应用互补变分原理的上下界方法高精度计算了大型变压器的短路电抗。并改进了恒定磁场的T-Ω方法,讨论了多介质场域复杂问题中T和Ω的选取、介质交界面及场域外边界面上边界条件的处理方法,以克服用互补Lagrange泛函求解短路电抗上界的困难。对五种类型的大型变压器的短路电抗进行了计算,其计算值与实测值比较,相对误差在2％左右。

In this paper, the short-circuit impedance of some large transformers are precisely calculated by the upper and lower bound method based on the complementary variation-al principles of magnetostic field. In order to calculate easily the upper bound of the impedance of a power apparatus with complex configuration by the principles, the previously T-Q algorithm has been improved. These methods are applied to calculate the shortcircuit impedances of five kinds of large transformers and the relative errors befween calculating and measuring values are approximately 2%.