Results of the Solar Cell Experiments Aboard the NTS-2 Satellite After 447 Days in Orbit.
Abstract
Results after 447 days in orbit of the solar cell experiments aboard the NTS-2 satellite are presented. The objective of the solar cell experiment, consisting of 15 separate experiments of five cells each, is to evaluate the performance of state-of-the-art solar cells in the space environment. Telemetered data from the 14 silicon and one gallium arsenide modules indicate a more severe radiation environment in the 63 degree, 20,190 km circular orbit than was predicted. Based on the NTS-2 data, the solar power array containing Spectrolab Helios cells will degrade 27% in maximum power over the three-year mission. Solar cell panel temperatures have reached 104 C providing ideal conditions for annealing of the radiation-induced damage in the gallium arsenide cells. After 15 months of operation these cells have suffered the least power degradation, with a maximum power loss of 14.0%. After 447 days in orbit, the loss in power ranged from 14.0% to 59.5% with the exception of the Solarex 'low-cost space cell' which became open-circuited on the 69th day. The average value of I sub sc measured in space on the first day of exposure agreed with prelaunch solar simulator values to within 1 + or - 0.99%. The agreement between V sub oc in space and solar simulator values was 1.24 + or - 1.08%. Results are summarized of the changes in the photovoltaic parameters of each of the experiments. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 09, 1979
- Accession Number
- ADA069082
Entities
People
- D. H. Walker
- R. L. Statler
Organizations
- United States Naval Research Laboratory