Abstract: For the high-precision control of Lorentz-force magnetically levitated rotary joints, the translational-rotational decoupling control method and its optimization method are proposed, which improve the stability and control performance of the system. The dynamics of the rotary joints is modeled according to the rotor dynamics, and the system is determined to be fully controllable according to the controllability rank criterion of the linear time-varying system. We design a decoupling controller, and optimize the controller by adding a phase compensator, which can make the closedloop dominant pole of the system shift to the left. The changes of control performance of the control system before and after optimization are compared by simulation analysis and experimental verification. The results show that the proposed optimization method of decoupling control can effectively improve the stability and dynamic performance of the magnetically levitated rotary joints control system, and the system regulation time is shortened by 50%, while the overshoot is reduced by 12%. The optimization effect is relatively obvious.

Key words: Lorentz force magnetic levitation, rotary joints, dynamical modeling, decoupling control, controller optimization