小型电子感应加速器利用磁场约束和感应电场加速电子束，使其在加速管中运动，最终轰击靶材产生X射线。小型电子感应加速器产生的X射线强度和剂量率与磁感应强度密切相关，而磁感应强度又受到励磁电流、线圈匝数和磁极材料等因素的影响。为研究永磁体对小型电子感应加速器磁场的影响，通过Poisson程序建立模型，并进行仿真分析。结果表明：在上下磁极头底部对称放置厚度为0.5 cm、矫顽力为1.062×10⁶ A/m、剩磁为1.401 T的永磁体，能够有效增强磁极头处的磁感应强度，电子束平衡轨道附近的磁感应强度提升了约18.6%，在相同磁感应强度要求下，加入永磁体可以使所需的励磁电流降低约33.8%。综上所述，永磁体与电磁铁相结合的方法可以有效提升小型电子感应加速器的性能。

Betatrons use magnetic field confinement and induced electric fields to accelerate electron beams, making them move in the accelerator tube and eventually bombard the target to produce X-rays. The intensity and dose rate of X-rays produced by the accelerator are closely related to its magnetic induction intensity. The magnetic induction intensity is affected by many factors such as excitation current, number of coil turns and magnetic pole material. In order to study the influence of permanent magnets on the magnetic field of Betatrons, a model was established by Poisson program, and simulation analysis was carried out. The results show that the permanent magnets with a thickness of 0.5 cm, a coercivity of 1.062 × 10⁶ A/m, and a residual magnetism of 1.401 T are symmetrically placed at the bottom of the upper and lower pole heads, which could effectively enhance the magnetic induction strength at the pole head, and the magnetic induction strength near the electron beam equilibrium orbital is increased by about 18.6%. Under the same magnetic induction strength requirements, the addition of permanent magnets can reduce the required excitation current by about 33.8%. In summary, the method of combining permanent magnets with electromagnets can effectively improve the performance of Betatrons.