Commercial Solar Electric Propulsion: A Roadmap for Exploration

1.5 kW Solar Electric Propulsion (SEP) systems in commercial production for over a decade enable cost-effective and mass-efficient in space transportation. Today's Second Generation 5 kW class Hall Effect thrusters, share a common flight proven design and production legacy that has been carefully evolved by a factor of three. Providing 300% more thrust these flight proven systems are suitable for Discovery class exploration missions carrying significant sensors and/or targeting faraway objects. The recent emergence of a third generation of commercial technology is being achieved through a second 300% growth in scale making possible low-risk steps toward 15-kW class thrusters. When combined with large scale, high power solar arrays and higher voltage power processing equipment, large in space mass transportation missions can be achieved at dramatically lower cost compared to chemical propulsion missions. Fielding these highly reliable technologies for exploration missions is made possible by commercial bottom line driven product development approaches which are strongly focused on early product configuration decisions, modularity and scalability. To succeed in the highly competitive global market, commercial practices demand high reliability features be demonstrated over 15 year missions with rigorous qualification to an envelope of application environments and products designed for manufacturability. To date Maxar has flown well over 100 hall thruster engine systems on commercial spacecraft, without a system level failure impacting Spacecraft performance. Anchoring these emerging technologies in ongoing commercial production across the full SEP power spectrum is vital to maintaining the legacy of low cost and high reliability introduced by the 1st generation of commercial SEP. In addition to a commercial SEP roadmap covering the evolution of smaller planetary, and enhanced large space transportation capabilities, two examples are highlighted of exploration missions enabled by commercial SEP optimized for deep space operations. One illustrates how the Psyche Discovery mission's 20kW SEP chassis design was extracted from Maxar's Space Solutions commercial product line for the exploration of then main belt asteroid 16 Psyche. The second features the much larger third generation Power Propulsion Element (PPE) or “space tug” being developed for the Deep Space Gateway. PPE is a 50 kW class state of the art SEP spacecraft that is capable of Cislunar and Mars missions.