Radial position effects of externally mounted hollow cathode on a magnetically shielded Hall thruster

A magnetically shielded Hall thruster (MSHT) has a significantly longer service life than a conventional unshielded Hall thruster (USHT) as it shifts the magnetic field of maximum strength from the channel interior to the exterior. In this study, it was experimentally determined that the influence of the radial position of an externally mounted hollow cathode on the performance of an MSHT is quite different from that of a USHT. The measured plasma parameters demonstrate that in addition to the coupling voltage loss and plume divergence loss, the electron cross-field transport loss (not considered previously and introduced by the outward shifting of the magnetic field) is also important to explaining the performance variation in the MSHT. This study refines the coupling theory between the cathode and Hall thruster and provides a valuable reference for determining the radial position of an externally mounted hollow cathode in an MSHT. Published under an exclusive license by AIP Publishing.

Automated summary

A magnetically shielded Hall thruster (MSHT) has a longer service life than a conventional unshielded Hall thruster (USHT) due to the shifting of the magnetic field. This study demonstrates that the radial position of the externally mounted hollow cathode has a different influence on the performance of the MSHT compared to the USHT. In addition, the study introduces the concept of electron cross-field transport loss, which was not previously considered.