Sample ground and flight tests: arching of negatively biased SSF wrapthrough solar cells

摘要

The Physical Sciences Inc. (PSI) Ultra-High Vacuum plasma test facility and optical diagnositics have been utilized to test the negatively biased are behavior of SAMPIE flight couponse containing segments of Space Station Freedom (SSF) wrapthrough solar cells. Preflight experimental tests focused on discovering are electrical characteristics, are frequency conditionsing with extended plasma exposure, parasitic current collection, and images of arc locations. Arcing was observed at solar cell edges and declined with plasma exposure time at a fixed negative bias. A coupon with excess adhesive removed from the solar cell edges exhibited lower arching rates, but increased parasitic current collection. Flight data on the arcing behavior of the SSF coupons was very limited, and the statistics were not good. However, the flight data incicates a propensity to arc during high pressure high plasma conditions. This observation supports previous evdience that surface contamination, especially water vapor contributes to the arc initiation process.