为了快速获取电气设备的瞬态磁场变化及损耗，研究时谐磁场的快速计算方法具有重要意义。通过使用时谐场仿真与本征正交分解—代理模型相结合的方法，实现了对高次谐波下磁场分布与损耗的快速计算。为了提高计算方法的精度，引入了一种能够自动选择线性多项式阶数的改进径向基函数响应面模型。与包含线性多项式的径向基函数响应面模型相比，该改进模型进一步提升了其工程适用性与计算精度。为验证所提方法的有效性，首先以TEAM7为研究对象进行时谐场的全阶仿真与降阶分析，证明了所提方法的准确性。同时，将所提方法与传统径向基函数响应面法以及包含线性多项式的径向基函数方法进行比较，结果显示所提方法在精度上有明显的提升。最后，应用本征正交分解与改进包含线性多项式的径向基函数响应面相结合的方法对一台变压器的时谐磁场进行降阶计算。结果表明，在计算磁场时降阶计算在计算时间上具有显著优势，且相对误差较小。

To rapidly obtain the transient magnetic field variations and losses of electrical equipment, studying fast calculation methods for time-harmonic magnetic fields is of great significance. By combining time-harmonic field simulation with the proper orthogonal decomposition （POD) and surrogate modeling approach, rapid calculation of magnetic field distribution and losses under high-order harmonics is achieved. To improve the accuracy of the calculation method, an improved radial basis function （RBF) response surface model capable of automatically selecting the order of linear polynomials was introduced. Compared to the RBF response surface model incorporating linear polynomials, this improved model further enhances its engineering applicability and computational accuracy. To validate the effectiveness of the proposed method, full-order simulation and reduced-order analysis of the time-harmonic field are first conducted on the TEAM7 problem, demonstrating the accuracy of the proposed approach. Additionally, the proposed method is compared with traditional RBF response surface methods and RBF methods incorporating linear polynomials, with results showing a significant improvement in accuracy. Finally, the POD and improved RBF response surface method with linear polynomials are combined to perform reduced-order calculations for the time-harmonic magnetic field of a transformer. The results indicate that the reduced-order calculation offers a significant advantage in computational time while maintaining relatively small errors.