OptSAT
About the mission
The OptSAT project is a German earth observation satellite system, build by OHB Space Systems and DLR.
The main payload is a space based high resolution instrument, electro optical camera unit FPA Focal-Plane-Array, produced by DLR Berlin.
Secondary regulation galvanically isolated (transformer-coupled)
The FPA is the improved next generation of TDI-Detector also with panchromatic (PAN) + multispectral (MS) focal level modules.
The resolution of about 20-30cm is one of the best in the world and is not only the first optical VHR system built in Germany.
Heritage and baseline of the FPA camera is active operating in space at south korean earth observation satellites (KompSat 3 + KompSat 3A + KompSat-7).
APCON´s OPTSAT PSU power supply is actually in the flight model series production phase for currently 20 FM units, even more in the future is planned.
The OPTSAT PSU-Set (VPSU-box) consists of 6 individual and identical sub unit power-supply-slices, with modular design to adjust easliy to different camera or S/C-BUS requirements.
All VPSU subunits (mechanical VPSU-slices) are mounted together to one VPSU-box.
Special Features
- Power supply is based on a discrete design architecture.
- Input Filter
- Input Inrush Current Limiter
- Input Voltage Limiter (Transient protection)
- ACM Buck (average current mode regulated) DC/DC-Converter
- Series Regulators
- Secondary regulation galvanically isolated (transformer-coupled)
- VPSU-box provides 84 (6* 14 and from that 11 are different) redundant output voltages to the FPA/FPU Camera Unit.
- The VPSU-box will be supplied separately with 6 times 28V-S/C-Bus voltages from the S/CPower distribution unit.
- Switching each primary power line to be OFF/ON commanded individually by High Power Commands (HPC) to switch_ON/OFF of the 28V-busvoltage.
- 12 independent “power-Enable” control Inputs
- 12 independent Housekeeping interfaces
- Each PSU-slice has one 28V-input primary stage, used for MS- and PAN-side.
- Secondary power block, consisting of PSU-P output voltage block (6 output voltages for CCD-PAN) as well as PSU-M output voltages block (5 output voltages for CCD-MS) in each PSU-slice.
- Three VPSU-slices are working as main power supply, the other three VPSU-silces are cold redundant.
Main power characteristics
- Primary Transformer 20V / 5 A
- -15V / 0,2 A (peak current 0,4 A) / 3,4 W
- +14V /0,20 A (peak current 0,9 A) / 3,4 W
- +20V / 0,5 A (peak current 0,8 A) / 11,0 W
- +7,5V / 0,9 A (peak current 2,6 A) / 7,9 W
- +7,5V / 2,00 A (peak current 4,5…6A) / 17,65 W
- +9.0V / 1,20 A (peak current 2,1 A) /13,8 W
- +6.1V / 3,00 A (peak current 4A) /21,5 W
- +12V / 0,30 A / 3,60 W
- Power Consumption: 61 W + 34 W = 95 Watt nominal






