Different design-technological modifications of PVCs are produced depending on specific operating conditions:
Characteristics of Photovoltaic Cells at АМ0 (1360 W/m2) and Т = 28 °С
Material |
Si |
GaInP2 / GaAs / Ge |
---|---|---|
Solar cell thickness, μm |
190 ± 30 | 150 ± 20, 100 ± 20 |
Integrated bypass diode | Available | Available |
Today, Saturn PJSC has successful experience of gallium arsenide solar cells selling to customers for the manufacturing of small spacecraft of CubeSat size.
Type of Photovoltaic Cells |
Si |
GaInP2 / GaAs / Ge series 28 |
GaInP2 / GaAs / Ge series 30 |
---|---|---|---|
Short-Circuit Current Density, Jsc, mА/сm2 | 41–46 | 16.8 | 17.44 |
Open Circuit Voltage, Uoc, V | 0.61–0.63 | 2.667 | 2.685 |
Current at Maximum Power, Jmp, mА/сm2 | 44.0 | 16.1 | 16.82 |
Voltage at Maximum Power, Ump, V | 0.52 | 2.371 | 2.394 |
Average Efficiency, η, % | 15.5 | 28.0 | 29.5 |
d ISC / dT | μА / сm2 / °С | 19.8 | 10.6 |
d IMP / dT | μА / сm2 / °С | — | 9.3 |
d UOC / dT | mV / °С | –1.92 | –6.0 |
d UMP / dT | mV / °С | –2.0 | –6.1 |
d PMP / dT | mW / сm2 / °С | –0.068 | –0.090 |
When operating in outer space, solar arrays and, accordingly, photovoltaic cells are exposed to radiation (Earth radiation belts, solar and space radiation), resulting in gradual degradation of their electric characteristics. PVCs’ radiation resistance in ground conditions is investigated by impact of monoenergetic beam of electrons with energy of 1 MeV (equivalent electron flow).
Fluence, e/сm2 | 1Е14 | 2,5Е14 | 5Е14 | 1Е15 | 3Е15 | 1Е16 | ||
---|---|---|---|---|---|---|---|---|
Types of PVCs | Si | GIP GaAs Ge | GIP GaAs Ge | Si | GIP GaAs Ge | Si | GIP GaAs Ge | Si |
JSC | 0.915 | 0.99 | 0.99 | 0.794 | 0.96 | 0.737 | 0.87 | 0.674 |
UOC | 0.845 | 0.96 | 0.95 | 0.777 | 0.93 | 0.744 | 0.90 | 0.693 |
JMP | 0.931 | 0.97 | 0.95 | 0.797 | 0.94 | 0.738 | 0.84 | 0.642 |
UMP | 0.839 | 0.96 | 0.94 | 0.763 | 0.93 | 0.725 | 0.90 | 0.664 |
PMP | 0.781 | 0.95 | 0.92 | 0.608 | 0.88 | 0.535 | 0.76 | 0.426 |
Ce-doped glass of K-208 grade (100 ± 20) µm thick is used to protect PVCs from space aggressive effects. The cover glass size exceeds that of PVC by 0.2 mm.
Special coatings are applied on glass plates depending on particular project requirements: