Study Of Permanent Magnet Spherical Motor Control Based On Two Electrifying Strategies

The Permanent Magnet Spherical Motor(PMSM)is a multivariable,nonlinear and strong coupling system.The external disturbance,the evaluated error of the parameters and the model error affect the effects of its motion control.The complex structure of the PMSM leads to the complexity of the relationship between electromagnetic torque and coil current,which makes it difficult to combine dynamic control with current control.The previous research on dynamic control lacks a clear energization strategy and the previous research on energization strategy often separates from dynamic control.This paper revolves around the two problems to make the corresponding research.Aim at uncertainty factors seriously affecting the effects of the motion control,this paper puts forward two kinds of dynamic control method to suppress the uncertainty factors on the trajectory tracking interference.Aim at the combination of the dynamic control and current control,this paper uses two energization strategy,achieves the random position switching of the PMSM and the PMSM spinning motion and the PMSM yawing motion under the minimum stator winding loss respectively.Firstly,based on the spherical motor stator and rotor structure,the static torque model is set up.And based on the dynamic model of PMSM,according to the structure of spherical motor and supporting parts,this paper establishes three degrees of freedom friction torque model.And.According to the static torque model,dynamic model and friction torque model,we obtain a complete mathematical model of spherical motor.Then,in order to suppress the interference of uncertainty factors,this paper proposes a robust control method combined with energization strategy based on spherical planning to realize the real-time accurate trajectory tracking control of PMSM,and achieves the random position switching of the PMSM.The simulation results show that the proposed robust trajectory tracking control method has certain superiority,and verify the feasibility of the energization strategy.Finally,this paper decomposes three degrees of freedom movement of PMSM.The spinning motion and yawing motion are studied.Based on the characteristics of the static torque of PMSM,the optimization energization strategy based on the stator coil split phase is proposed,and achieves the spinning motion and yawing motion in the situation of minimum loss of stator coils.At the same time,this paper combines with an adaptive sliding mode control method with uncertainty compensation to have a real-time accurate trajectory tracking control.