The power subsystem's primary objectives are to generate, distribute, and store energy during the spacecraft’s entire mission lifetime for all mission modes. Proper and reliable functioning of the power system is therefore the key to any spacecraft mission success.


  • Solar photovoltaic system supplemented by secondary batteries.
  • Series regulated charge controller
  • Non-dissipative unregulated main bus type
  • Centralized regulation approach.


  • High efficiency multi-junction GaAs solar cells assembled in a class 10,000 clean room using USU developed and NASA approved assembly plan.
  • Fast charge Ni-Cd rechargeable battery with high cycle life and extensive flight heritage.
  • Innovative flat aluminum battery box design. Lightweight, robust, and built to follow all safety requirements.
  • Highly integrated electronics housed in the CEE.
  • System health monitors: temperature, current, and voltage sensors available for CDH.
  • Integrated Safety Inhibits
  • Space qualified or Mil-spec components
  • Built using Low outgassing and high quality materials
  • Extensive supporting documentation (COCs, Part lists, travelers).

Features and Capabilities:

  • Simple, low-cost, and lightweight.
  • Adaptable to handle additional loads
  • Orbit average solar cell power: 23 W
  • Battery capacity: 52.8 Whr
  • Available Margin: 30% (7 W)
  • Regulated buses: 3.3 V, 5 V, 12 V, -5 V, -12 V, 10 V, and 24 V.
  • Unregulated Main Bus: 15 V.
  • Complies with safety standards described by NSTS1700.7B, NSTS/ISS 18798, NASA TM 102179.
  • Power management software to monitor and control the system performance.
  • Scalable solar array using deployable panels
  • Electronics adaptable to both Ni-Cd as well as Ni-MH batteries.
  • Total system diagnosis using available test points and dedicated EGSE.
  • Supports LEO altitudes from 185 km to 1000 km.


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