Systems / Electrical Power System

Electrical Power System

Power generation, storage, and distribution for nanosatellites.

EOS-EPS-DSH-03 / Flown on LOGSATS-2

Electrical Power System flight unit render
Battery
45 Wh, 4-cell Li-ion
Solar input
3x MPPT, 20 V max
Output buses
3.3 V / 5 V / VBat
Mass
760 g

The EOS Orbit EPS integrates solar power harvesting, battery management, and protected power distribution in a single PC-104 module. Three MPPT channels track solar input, a four-cell battery pack stores 45 Wh, and switched 3.3 V, 5 V, and battery outputs deliver power through e-fuses with per-channel current and voltage telemetry.

The module manages its own thermal and fault behavior. An automated heater holds battery temperature in cold conditions, and dedicated power-saving and emergency low-power modes shed loads as rail voltage falls, then recover the system once solar charging restores it.

  • 4 kill switches and 1 RBF pin for flight safety
  • 3x MPPT solar inputs, 20 V / 2 A per channel
  • Output buses: 3.3 V, 5 V, BCR adjustable to 16.8 V, battery raw
  • E-fuse protection with per-channel power telemetry
  • Automated battery heater control
  • USB-C charging for ground operations
  • CAN, UART, and I2C interfaces
  • Optional stackable battery packs up to 8 A, RS-485, 6x GPIO load control

Electrical

Solar inputs 3x MPPT, 20 V max, 2 A per channel
Battery pack 4 cells in series, 13.5-16.8 V
Stored energy 45 Wh
Output channels 3x 5 V, 3x 3.3 V, battery raw
Output current 2 A per channel, 6 A per bus
Battery heater 2.5 W max

Interfaces

CAN 500 kbps command bus
UART 115200 bps, programming and debug
I2C 100 kbps peripheral control
USB-C USB 2.0, charging and development

Physical

Size 92 x 94 x 51.33 mm
Mass 760 g
Mounting PC-104 stack, 4x M3
Enclosure Aluminum 6061
Thermal vacuum 8 cycles, -20 to +60 °C, < 10⁻⁵ Torr, 1 h dwell at extremes
Radiation TID evaluated to 20 krad (Si), SEE tolerance, latch-up protection
Random vibration 14.1 gRMS, 20-2000 Hz
Functional burn-in 72-96 h continuous operation in vacuum
Electrical Power System mechanical drawing
92 x 94 x 51.33 mm / 4x M3 / dimensions in mm

Flown on LOGSATS-2. Launched January 15, 2025, on a SpaceX Falcon 9. 440 days of orbital operations.

Commission this system

Write to contact@eosorbit.com with your mission parameters. The engineering team responds with configuration options, lead time, and test documentation.

Contact engineering

EOS-EPS-DSH-03 / datasheet on request