Hall Thruster

This is the most advanced and efficient type of electric thrusters which is developed in a coaxial configuration where orthogonal electric and magnetic fields (ExB) are employed to ionize the propellant gases such as xenon. The resulting ions are accelerated and fly out producing thrust. As compared to the other ion thrusters, Hall thruster offer simple construction with no space charge limitation and other significant advantages include long operation life, high power density and high specific impulse range (1000-2000 s).

Figure 1 Layout of the experimental setup for testing the PPS®1350 thruster (DOI:https://doi.org/10.1088/0963-0252/23/6/065001)

Figure 1 shows the 1.5 kW class PPS®1350-ML thruster which is the laboratory model of the PPS®1350 thruster developed by Snecma that successfully propelled the MART-1 space probe during its journey to the Moon. A magnetized low-pressure dc discharge maintained between an external cathode and an anode. The anode, which serves as a gas injector, is located at the upstream end of a coaxial annular dielectric channel that confines the discharge. Xenon is used as the propellant gas. A set of solenoids or permanent magnets provides a radially directed magnetic field, the strength of which is maximum in the vicinity of the channel exhaust. The electric potential drop is mostly concentrated in the final section of the channel owing to the high electron resistivity. The electric field also accelerates ions out of the channel, which generates thrust. The ion beam is neutralized by a fraction of the electrons emitted from the cathode.