Characterization of advanced electric propulsion systems

Abstract

Characteristics of several advanced electric propulsion systems are evaluated and compared. The propulsion systems studied are mass driver, rail gun, MPD thruster, hydrogen free radical thruster and mercury electron bombardment ion engine. These are characterized by specific impulse, overall effiCiency, input power, average thrust, power to average thrust ratio and average thrust to dry weight ratio. Several important physical characteristics such as dry system mass, accelerator length, bore size and current pulse requirement are also evaluated in appropriate cases. Only the ion engine can operate at a specific impulse beyond 2000 sec. Rail gun, MPO thruster and free radical thru.ster are currently characterized by low efficiencies. Mass drivers have the best performance character1st1cs in terms of overall efficiency, power to average thrust ratio and average thrust to dry weight ratio. But, they can only operate at low specific impulses due to large power requirements and are extremely long due·to limitations of dri vi ng current. Mercury ion engines have the next best performance characteristics while operating at higher specific impulses. It is concluded that, overall, ion engines have somewhat better characteristics as compared to the other electric propulsion systems.17.

Ion Electric Propulsion System Electric Breakdown Problems: Causes, Impacts and Protection Strategies

“…Ion electric propulsion systems are one of the mainstream electric propulsion technologies in the world, and belong to electrostatic acceleration [33]- [36]. The input power of the ion electric propulsion system is usually solar energy converted into electricity by photo-electric conversion device, which ensures long-term spacecraft power [37].…”