Hall Thruster Plume Diagnostic System Based On LabVIEW

Hall thruster is widely used in space propulsion because of itsadvantages such as high specific impulse and precise control. The study ofplasma properties in the plume area is of great importance for the applicationof Hall thruster on spacecraft.In this thesis, a LabVIEW-based plasma diagnostic system wasdeveloped, which has the functions of motion control, data acquisition andanalysis, and report generation. Various parameters of the plasma in the Hallthruster plume area can be obtained. The work of the thesis is listed asfollows.(1) The motion control module was programmed by using LabVIEWand PLC.The system communicates between PC and PLC via OPC server,thus the probes could be located quickly and accurately in the Hall thrusterplume area.(2) The electron temperature and electron density in the plume area weremeasured through Langmuir single, double and triple probes. It was foundthat the measured results by Langmuir double and triple probes are morestable and accurate than that by Langmuir single probe, while Langmuirsingle probe could get the plasma parameters such as the space potential, ioncurrent, floating potential.(3) The beam divergence angle of the hall thruster could be measured bythe Faraday cup. The angle-current density curve could be obtained bycollecting the currents of19points uniformly distributed within180°. Thebeam divergence angle within which90%of ions distribute could becalculated by integrating the angle-current density curve. (4) The energy distribution of the Hall thruster plume was measured byRPA. The collector current curve corresponding to the loading of0~600Vvoltage on the RPA was observed. It was found that the change of the currentis determined by the number of ions located in the corresponding voltageenergy levels.Through the field testing, this system is proved to be fast in testing,accurate and friendly in human-computer interaction. The measured results ofelectron temperature, electron density, beam divergence angle and ion energydistribution in hall thruster plume is important to the application of Hallthruster in the satellite system.