In the discharge ground tests of satellites, an electron beam is mainly used to simulate the electron environment on geostationary orbit; however, the insulator is charged on the orbit by photoelectrons by vacuum ultraviolet rays during sunshine. Discharge occurs when the insulator surface exceeds the discharge threshold voltage. Whether the discharge threshold differs between the electron beam and the vacuum ultraviolet ray was experimentally investigated using a solar array coupon. As a result, the discharge threshold voltage was lower by about 1 kV when using vacuum ultraviolet light rather than when it was charged by using an electron beam. It was assumed that the electron beam was bent by the electric field at the edge of the solar cell, making it difficult to be charged, and detailed surface potential measurements were performed. As a result, a difference was observed in the surface charge distribution between the electron beam and vacuum ultraviolet light, and it was found that when the electron beam was used, the solar cell edge was less likely to be charged.
Difference in Discharge Threshold Voltage Between Electron Beam and Ultraviolet Environment
Journal of Spacecraft and Rockets ; 58 , 3 ; 619-627
2021-05-01
Conference paper , Article (Journal)
Electronic Resource
English