Structure Design And Experimental Research For Micro Inertia Momentum Wheel

Micro inertia momentum wheel is a significant actuator of space vehicles to achievehigh-precision attitude control, such as micro satellite. Small size, light weight, long life,high reliability, and low power consumption have been the goal pursued by the microinertia momentum wheel research. The performance of the micro inertia momentumwheel will impact on the accuracy, stability and power of the small satelliteattitude-control system, directly.Based on the characteristics of the micro inertial momentum wheel, the mechanicalstructure and electromagnetic structure are analyzed and designed detailedly to resolvethe existing problems in the structures. Then, the finite element analysis andexperimental research are performed. The study mainly includes the following:(1) By the mechanical and electrical integration design method, the overall designfor the mechanical structure of micro inertia momentum wheel, including motorstructure, rotor components, shafting and lubricating, the base, sealing and structuraldesign, connectors, suction mouth, ground piles, and other ancillary parts, and design ofthe installing base, etc. In order to ensure the imbalance of the rotor, some appropriatemeasures are adopted.(2) By the field-curcuit method, the specific analysis of the design process ispresented for the stator and rotor of the dual-rotor structure motor, permanent magnets,and the overall structure. Then, the relevant parameters are calculated, different designschemes are analyzed and compared, and the final design scheme as well as size aregiven.(3) The structural modes and the air-gap flux density are analyzed and the conceptof “air-gap flux density waveform degree” is proposed. Then, three-phase winding backEMFs and torque fluctuation are educed through through the air-gap flux densitywaveform. The power loss and magnetic flux leakage in the end are analyzed, too. Inthe analysis, the performance for the outer-rotor and dual-rotor structures are compared.(4) The rotor core material and the stator windings were tested. The air-gap fluxdensity waveform and the magnetic flux leakage in the end are measured. Then, theback EMFs waveform and torque fluctuation factor are obtained by the experiments.Finally, the deceleration power loss is calculated and is compared with the results of theouter-rotor structure by deceleration experiments.