Mpt Experimental System Monitoring And Control Technology Research

Electric Propulsion (EP) has many advantages of high specific impulse, long lifetime and high controlling precision. It can perform many kinds of space mission, and many countries have taken more attention on it. Microwave Plasma Thruster (MPT) is studied in College of Astronautics, Northwestern Polytechnical University and it is a new type of electro-thermal thruster. In order to study the performance of MPT more experiments must be taken, and an instant, exact and convenient system of measuring and controlling is very important in all of these experiments.This paper aimed to establish the system of measuring and controlling for the experiment of MPT, and Virtual Instrument was used in order to improve the accuracy and reliability of measuring and controlling. In addition, with theoretic analysis and experimental confirmation, we got the accuracy of every parts and total system.The contents of this paper include:1. Thermal Profile Mass Flow Controller (MFC) and Glass Rotor Flow Meter was used in the measurement and control of flux. The MFC was used to measure and control the flux, and the Rotor Flow Meter was for the use of flux detection. The accuracy of the MFC was 3.8%FS, and the Rotor Flow Meter's was 2%FS.2. The measurement of pressure was carried out by using semiconductor silicon piezometer. With the static pressure in inlet of pipeline and theoretic analysis we could get the total pressure of MPT. The accuracy of piezometer was 2%FS.3.The new Microwave Power Supply (MPS) can work in vacuum and its power measurement is convenient. The output power could be adjusted with the change of control voltage, and the reflecting power could be gotten by measuring the output voltage of attenuator and detector.4.The thrust measurement device was calibrated, and the accuracy was 2%FS. At the same time the signal of thrust measurement was input to the computer. E-type chromel-constantan thermocouple was used to measure the temperature of MPT, and the accuracy was 5%FS.The vacuum measurement was realized by using ZDF-5427M vacuometer, and the accuracy was 3%FS.5.The software of Virtual Instrument measurement and controlling system based on LabVIEW 6.1 was developed in order to improve its convenience and immediacy..Some ignition and steady work experiments of MPT were operated in order to verify the system of measuring and controlling. All of experiments indicates that the system of measuring and controlling is exact, convenient and credible, and parameters' measuring and controlling is automatic. This system is sufficiently satisfied to the experiment and will play an important role in the research of MPT.