Mass savings domain of plasma propulsion for LEO to GEO transfer

A parametric model is used to study the mass savings of plasma propulsion over advanced chemical propulsion for lower-Earth-orbit to geosynchronous-Earth-orbit transfer. Such savings are characterized by stringent requirements of massive payloads [0(10) metric tons] and high-power levels [0(100) kW]. Mass savings on the order of the payload mass are possible but at the expense of longer transfer times (8-20 months). Typical of the savings domain is the case of a self-field magnetoplasmadynamic (MPD) thruster running quasisteadily, at an Is of 2000 s, with 600 kW of input power, raising a 50 metric ton satellite in 270 days. The initial mass at LEO will be 65 ton less than a 155 ton LOi/LHi advanced chemical high thrust spacecraft. An optimum Is can only be found if the cost savings associated with mass savings are counterbalanced by the cost losses incurred by longer transfer times. A simplistic cost model that illustrates the overall trends in the optimization yielded an optimum Is of about 2200 s for a cost effective baseline MPD system.