Modeling for the Electromagnetic Dynamic Distortion Effect of the Induction-Based Electrodynamic Suspension Reaction Spheres

The electrodynamic suspension reaction sphere (EDSRS) is regarded as a novel actuator for the spacecraft attitude control system. The omnidirectional rotation of the EDSRS spherical rotor brings about the dynamic distortion of the electromagnetic force and torque characteristics. With the mechanical structure of the EDSRS simplified and equivalent to multi-degrees of freedom (DOF) single-sided linear induction motor (LIM), this article first proposes a 3-D LIM analytical electromagnetic force model by employing the electromagnetic physical quantities in the 2-D Fourier series expansion form. Then, an analytical electromagnetic force and torque model considering the electromagnetic dynamic distortion effect (EDDE) of the EDSRS is established based on the previous LIM force model according to the motion decomposition principle. Finally, the proposed analytical EDDE model is experimentally validated on the developed laboratory prototype.