Accession Number : ADA181068

Title :   Pulsed Inductive Thruster Component Technology.

Descriptive Note : Final rept. 1 Oct 82-31 Oct 86,

Corporate Author : TRW SPACE AND TECHNOLOGY GROUP REDONDO BEACH CA APPLIED TECHNOLOGY DIV

Personal Author(s) : Dailey,C. L. ; Lovberg,R. H.

Report Date : APR 1987

Pagination or Media Count : 83

Abstract : The pulsed inductive thruster (PIT) is an electrical propulsion device that accelerates a plasma propellant by the JxB Lorentz force, and in which the driving current in the plasma is induced, rather than being introduced through electrodes. This program addressed: thruster circuit component design; plasma probe diagnostics and thrust balance measurements for two of the three thruster designs developed during the program; design a flight-type capacitor; capacitor pad life testing; and demonstration of the system in the clamped discharge mode. A numerical simulation of thruster operation was developed and used to elucidate the effects on efficiency of circuit parameters, plasma conductivity and scale size. Capacitor tests results indicated very long life is obtainable wih modest voltage derating using paper/polypropylene capacitors. Development of a successful scheme for high power, high frequency diode clamping has made it possible to operate without significant capacitor voltage reversal, and hence to extend capacitor life by up to two orders of magnitude. A life demonstration of the propellant injection valve exceeded the goal of one million cycles; however, a rotary device may be better suited for the PIT. Plasma probe diagnostics were helpful in understanding thruster operation. Both current density and magnetic field probes showed the need for testing with a larger vacuum changer to thruster coil diameter ratio, and with a stronger induced electric field to ionize and drive the plasma current. Keywords: Magnetic plasms accelerators; Electric propulsion.

Descriptors :   *ELECTRIC PROPULSION, CAPACITORS, CIRCUITS, CLAMPS, COILS, CONDUCTIVITY, DIAMETERS, DIODES, BALANCE, ELECTRICAL EQUIPMENT, ELECTRODES, HIGH FREQUENCY, HIGH POWER, INJECTION, LONG LIFE, LORENTZ FORCE, MATHEMATICAL MODELS, MEASUREMENT, NUMERICAL ANALYSIS, OPERATION, PLASMA DIAGNOSTICS, PLASMAS(PHYSICS), PROBES, PROPELLANTS, RATIOS, REVERSIBLE, SCALE, SIZES(DIMENSIONS), THRUST, THRUSTERS, VACUUM, VALVES, VOLTAGE

Subject Categories : Electric and Ion Propulsion

Distribution Statement : APPROVED FOR PUBLIC RELEASE