用镜象法计算超导发电机的三维磁场和参数

APPLICATION OF IMAGF METHOD TO CALCULATING 3-D MAGNETIC FIELD AND PARAMETERS OF SC ALTERNATOR

本文提出用镜象法计算超导交流发电机的三维磁场和参数。导磁和导电边界对磁场的影响用相应的镜象电流的作用来代替。电机的有限长度及环境屏的阶梯形或圆锥形端部使端部磁场逐渐减弱,它可以通过使端部区域的镜象电流沿着某个锥形面逐渐向外倾斜来进行处理,调节锥形面的锥角以及锥面起始端和末端在轴线上的位置,使端部磁场的边界条件得到较好的满足,从而提高了磁场和参数计算的精确度。

The image method is used for calculating three dimensional magnetic field and parameters of the superconducting ac generator. The finite length of the machine and either stepped or conical end regions of the environmental iron shield tend to make the magnetic field in the end reigons weakened. It is treated by forming the image currents in the end regions on a conical surface whose conical angle and length as well as its axial position may be ad- justed so that the boundary condition of the magnetic field in the end regions will be well satisfied. Consequently, the accuracy of both magnetic field and para- meters calculations may be increased.