Optical Spectrum Diagnose And Pattern Recognition For The Plume Of SPT

Stationary Plasma Thruster(SPT)as one kind of hall thruster will be used broadly in spaceflight, it can provide power for satellites control, orbit shift and so on. The followings are its advantages: small cubage, compact configuration, little thruster, great specific impulse. This kind of thruster has a long life-span with which it can be used for exploration far away, available load and expense for spacecraft can also be improved. Spectrum diagnose is a contactless method without perturbation. As an important means, it has some particular advantages compared with the others, it is convenient to use it for measurement of plasma parameters and analysis of characteristics for thruster. In this work, the system of optical spectrum measurement including software and hardware which is suitable for diagnose of SPT was set up; experimental research and analysis for the plume of SPT were carried out; the characteristics of plume under different working conditions were got with the mechanism of excitation for upper level considered, the conclusions can be references for SPT diagnose, the details are followings:A spectral model based on the mechanism of SPT was got. Energy levels and spectrum characteristics of xenon were concluded after the discussion for selecting Xenon as propellant, spectrum lines broadening and hyperfine splitting were also introduced; excitation were classified based on the mechanism of origin for upper levels, spectrum analysis and obtaining of spectral model were carry out; excitation in different parts of SPT was also analyzed because of different energy and density distribution for particles.The system of optical spectrum measurement was set up. The scheme for this optical system was discussed in detail, it included optical measurement theory, characteristics of optical discreteness, process of optical rectification, affect of optical discreteness for spectrum signal. The error for this system was also analyzed.The diagnosis of SPT plume was carried out based on colour and shape of plume. Colour and shape of plume are different under some working conditions; in this work, optical measurements of green plume, fuchsia plume, salmon pink plume were carried out, spectrum analysis was associated with mechanism of...