To obtain engineering-feasible designs of stellarators with permanent magnets and simplified coils, a new algorithm has been developed based on Fourier decomposition and surface magnetic charges method. The strong toroidal fields in a quasi-axisymmetric stellarator are still generated by coils. The permanent magnets are designed to compensate the normal magnetic field B _n on the plasma surface ∂P created by the coils and plasma. The normal magnetic fields created by the permanent magnets B _pmn are calculated as the difference between the magnetic fields created by the surface magnetic charges on the inner surface ∂D and the outer surface ∂D _h of the magnets. The Fourier coefficients of the magnet thickness function are computed through matrix division operation based on the least square principle with dominant Fourier components selected through 2D Fourier transformation of B _pmn. The residual uncompensated B _n is minimized through iteration to progressively optimize the thickness function. This new algorithm has been successfully applied to design the permanent magnets of an l = 2 quasi-axisymmetric stellarator with background magnetic field created by 12 identical circular planar coils for demonstrations. High accuracy has been achieved, allowing for a flux-surface-averaged residual B _n relative to the total field and a maximum residual B _n of less than 2 Gs for ∼1T total field. This new design has some advantages in engineering implementations: all permanent magnet pieces have the same remanence B _r; only one single layer of magnets are mounted perpendicular to the winding surface; the magnets can be easily inserted into the cells of a gridded frame attached to the winding surface and fixed with springs from the back, which greatly simplifies the manufacture, assembly and maintenance of the magnets, and thus facilitates precision control and cost reduction.

为了获得具有永磁体和简化线圈的恒星的工程可行设计，基于傅立叶分解和表面磁化方法开发了一种新算法。准轴对称恒星器中的强环形场仍然由线圈产生。永磁体被设计成补偿正常磁场乙 _Ñ等离子体表面∂上P由线圈和等离子产生。由永磁体产生的正常磁场乙_PMN被计算为通过表面磁荷的内表面上∂产生的磁场之间的差值d和外表面∂ d _ħ 的磁铁。磁体厚度函数的傅立叶系数是通过基于最小二乘原理的矩阵除法运算，并通过B _pmn的2D傅立叶变换来选择占主导地位的傅立叶分量。通过迭代将残差未补偿的B _n最小化，以逐步优化厚度函数。该新算法已成功应用于设计l = 2准轴对称恒星的永磁体，该永磁体具有由12个相同的圆形平面线圈产生的背景磁场进行演示。实现了高精度，允许相对于整个磁场的通量表面平均残差B _n 对于约1T的总场，最大残留B _n小于2 Gs。这种新设计在工程实施中具有一些优势：所有永磁体块具有相同的剩磁B _r；垂直于绕组表面仅安装了一层磁铁；磁体可以很容易地插入到安装在绕组表面的网格框架的单元中，并通过背面的弹簧固定，从而大大简化了磁体的制造，组装和维护，从而有助于精确控制和降低成本。