Novel microplasma thruster using microhollow cathode discharge

The development and application of micro-satellites urgently needs new types of micro-thrusters. As an important classification of plasma discharges, microdischarge is favoured with considerable interest in the plasma field over the past decade. Microhollow cathode discharge (MHCD) is a kind of high pressure, non-equilibrium gas discharges. It can be operated with relatively low voltage (several hundreds volts) or input power(in the order of several hundreds of milliwatts) and it has an advantages of stable discharge under the high pressure. The MHCD device belongs to a kind of metal-dielectric-metal sandwich structure. Two electrodes (molybdenum or aluminium foils) are stacked on a dielectric layer (mica or alumina). The ports can be drilled through the sandwich with the hole diameter from dozen of microns to several hundreds microns. In combination of the extremely small dimensions and relative high and controllable gas temperature of the MHCD, it can be used as propulsion system of a new micro electro-thermal thruster. The performance of the micro plasma thruster using MHCD, such as specific impulse and thrust, will be higher than that of the conventional cold gas micro-thruster, because the propellant gas is heated in the microdischarge plasma thruster and then expand through the micro-nozzle to produce the thrust.