Solar Array Structures for 300 kW-Class Spacecraft

State-of-the-art solar arrays for spacecraft provide on the order of 20 kW of electrical power, and they usually consist of 3J solar cells bonded to hinged rigid panels about 1 inch in thickness. This structural construction allows specific mass and packaging volumes of up to approximately 70 W/kg and 15 kW/m3 to be achieved. Significant advances in solar array structures are required for future very-high-power spacecraft (300+ kW), such as those proposed for pre-positioning heavy cargo on or near the Moon, Mars, or asteroids using solar electric propulsion. These applications will require considerable increases in both W/kg and kW/m3, and will undoubtedly require the use of flexible-substrate designs. This presentation summarizes work sponsored by NASA's Game Changing Development Program since Oct. 2011 to address the challenge of developing 300+ kW solar arrays. The work is primarily being done at NASA Langley, NASA Glenn, and two contractor teams (ATK and DSS), with technical collaboration from AFRL/Kirtland. The near-tem objective of the project is design, analysis, and testing of 30-50 kW solar array designs that are extensible to the far-term objective of 300+ kW. The work is currently focused on three designs: the MegaFlex concept by ATK, the Mega-ROSA concept by DSS, and an in-house 300-kW Government Reference Array concept. Each of these designs will be described in the presentation. Results obtained to date by the team, as well as future work plans, for the design, analysis, and testing of these large solar array structures will be summarized.