Optimal configuration of distributed HTS coils for the non-contact de-tumbling of space debris

Space debris generally exhibit complex rotating motions, which cause significant challenges when attempting to capture them in orbit. Reducing the rotational speed of the space debris before capturing them with a high rotational energy can reduce the risk of destructive collisions. The electromagnetic de-tumbling method based on eddy currents has the advantages of being non-contact, pollution-free, and exhibiting no orbital height limitations, among other qualities. To improve the efficiency of electromagnetic de-tumbling, distributed high-temperature superconducting (HTS) coils are used in this study. Specifically, a finite element model is established to investigate the induced currents and eddy-current torque, and the optimal configuration of the distributed coils is obtained using numerical optimization. The analysis of the external magnetic field shows that if the distance between the target and the coils exceeds four times the radius of the target, the eddy-current torque and the magnetic field at the center of the target will achieve maximum values in the same configuration, and the external magnetic field can therefore be regarded as a uniform field when calculating the eddy-current torque. Finally, the finite element model and the optimal configuration are verified using simplified ground-based experiments.