介绍了由于磁铁的安装误差和螺线管的存在而造成的束流径向和轴向的耦合,以及耦合对束流稳定的影响。结合CSRm结构的典型参数分析得出:二极磁铁和四极磁铁在纵向角安装偏差为-0.5~0.5mrad;有螺线管存在的情况下,工作点落在和共振线时,将导致束流不稳定而大量损失,落在差共振线时,束流稳定。通过模拟计算发现:螺线管产生的耦合远大于磁铁的纵向角安装偏差产生的耦合。 The radial and axial coupling of the beam due to the installation error of the magnet and the existence of the solenoid are introduced, and the influence of the coupling on the stability of the beam is introduced. According to the typical parameter analysis of CSRm structure, it can be concluded that the installation bias between the two-pole magnets and the quadrupole magnets is -0.5 ~ 0.5 mrad in the longitudinal direction. In the presence of a solenoid, when the operating point falls on the resonance line, Flow instability and a lot of loss, falling in the poor resonance line, the beam stability. The simulation results show that the coupling generated by the solenoid is much larger than the coupling caused by the misalignment of the magnet in the longitudinal direction.