Magnetic Topology to Stabilize Ionization Oscillation in Anode-layer-type Hall Thruster

Abstract

Ionization oscillation of a Hall thruster is one of the most serious problems. In order to suppress the ionization oscillation of an anode-layer-type Hall thruster, we tried to reduce the magnetic field in the anode hollow using a magnetic shield. Firstly, we validated the effectiveness of a magnetic shield with numerical simulation which was developed for the UT anode-layer-type Hall thruster (power: 1.7 kW, thrust: 93 mN, Isp: 1900 s). Secondly, we developed a new anode-layer-type Hall thruster in which anode hollow magnetic flux density is reduced using a magnetic shield and measured its oscillation amplitude and thrust efficiency. As a result, the oscillation amplitude was drastically reduced by the magnetic shield; the oscillation amplitude was less than 0.4 in the whole operation range. Moreover, the thrust efficiency is also improved by more than 10 percent by the magnetic shield.