Prisma PCDU

Prisma is a Swedish-led satellite project with the objective to develop and qualify new technology necessary for future science missions in space. Omnisys Instruments has designed and manufactured the Power Control and Distribution Unit, PCDU, on the two Prisma satellites called Mango and Tango.

The PCDU distributes power from the solar arrays to all the different user on the satellites via latching current limiters, LCL. The system also contains Li-Ion batteries for supplying power during sun eclipses. All control functions are hot redundant, allowing for any single failure to occur without affecting the system performance. This achieved through triple redundancy and voting of both digital and analogue control functions.

Key data of the Main PCDU:
Solar array power: 600 W
Number of users(LCL): 36
User power: 28 V regulated, up to 6A
Battery Energy: > 250 Wh
Control interface: CAN bus and pulse telecommands.

Analysis performed:
Worst Case
Part Stress
FMECA

Qualification tests performed:
Vibration
EMC
Thermal vacuum
Functional and performance

For more information about the Prisma satellites and their mission: http://www.prismasatellites.se/