The dual-winding bearingless flux-switching permanent magnet machines ( BFSPMM) is a non-linear and multi-variable complex system. The traditional speed PI and radial displacement PI control have disadvantage of large overshoot. The system is susceptible to external disturbances. Based on the idea of sliding mode variable structure control, this article proposes a sliding mode control (SMC) strategy for the radial displacement of Dual-winding BFSPMM to control the suspension plane. In view of the inaccurate mathematical model in sliding mode control, the gyro effect in the rotor dynamics, etc. An extended state observer (ESO) is established to observe the system disturbance, and the disturbance feedforward compensation control is added to SMC. Thus, a compound control strategy of SMC and ESO is formed. Compared with the traditional PI control, experimental results show that the proposed radial displacement SMC has advantages of faster response speed, smaller radial displacement pulsation, and strong resistance to load disturbances. Compared with the radial displacement SMC, the proposed composite control strategy of radial displacement SMC and ESO can effectively reduce the radial displacement pulsation of the rotor by about 30% , and further enhance the robustness of the system.