First Full EPS Prototype

April 4, 2025

Author: Ben Kellman

MARMOTSat relies on a high-efficiency solar array with 48 solar cells to generate power. When in sunlight, the Power Conditioning and Distribution Module (PCDM) distributes this energy to the spacecraft’s subsystems while storing excess power. When MARMOTSat moves into Earth's shadow, it switches to its battery pack to keep operations running.

The battery pack, which consists of 8 Lithium Titanate Oxide (LTO) batteries, operates reliably even in subzero temperatures. This eliminates the need for a battery heater—a common component in other CubeSat—reducing both power consumption and design complexity. Together, the solar array, battery pack, and PCDM form MARMOTSat’s Electrical Power System (EPS).

Recently, the first full prototype of the PCDM and battery pack was successfully assembled and tested by the MARMOTSat team at UVic. This milestone provided valuable insights, allowing us to refine the design for a second revision. The next iteration will be simpler and more efficient, bringing MARMOTSat closer to its final flight-ready form.

Fully assembled PCDM and battery pack with EGSE board