Bepi Colombo Mercury Magnetospheric Orbiter Solar Array Development
Abstract
This paper reports the development process of the solar array for the Mercury probe called the Mercury Magnetospheric Orbiter. Because the spacecraft is going be exposed to intense sunlight up to 11 suns, the temperature of the solar array is expected to reach as high as 230oC. We evaluated the degradation in the electrical output of the solar cells by using high intensity and high temperature (HIHT) tests, and found out that a decrease in the transmittance of the DC93-500 adhesive caused by UV irradiation at high temperature led to decreased current output. By using coverglasses, which effectively cut the UV light, we could successfully minimize the decrease in the electrical output. We subjected coupon panels to a thermal vacuum test. We found an unusually large number of solar cells detaching from the substrate, which would lead to increased temperature, and cracked cells. We assumed that this problem was caused by interconnects whose stress reliefs were buried in adhesive due to a requirement of the scientific instruments. We increased the gap between adjacent cells to allow the stress reliefs to work effectively. We also conducted a proton irradiation test at 180oC to evaluate radiation damage at high temperature. The damage was confirmed to be identical to that at room temperature.
- Publication:
-
9th European Space Power Conference
- Pub Date:
- October 2011
- Bibcode:
- 2011ESASP.690E..99T