ISIS Modular Electrical Power System

The ISIS Modular Electrical Power Subsystem version 2 (v2) is the second-generation modular EPS designed and manufactured by ISIS. IMEPSv2 is designed as a flexible EPS targeting larger nano-satellites and microsatellites from 3U upwards. Using recent high-performance technology, the EPS provides improved efficiency over the previous version while minimizing EMI. The modular architecture allows the EPS to be tailored to the needs of the platform without needing customization. The distributed design philosophy that underpins the IMEPS design allows unprecedented flexibility in output bus count and voltage, and enables tailorable redundancy to be applied for selectable parts of the platform, depending on the needs of the mission.

The IMEPS consists of four types of elements:

  • ISIS Power Conditioning Unit (IPCU) – Solar panel input to common power rail
  • ISIS Power Battery Unit (IPBU) – Secondary power storage and retrieval control
  • ISIS Power Battery Pack (IPBP) – Battery holder with integrated fuse
  • ISIS Power Distribution Unit (IPDU) – Power regulation to attached subsystem loads

One or more of each of these units can be combined to form the platform EPS.



Additional – Battery packs

  • Up to three battery packs (IPBP) per battery unit board (IPBU)
  • Each additional IPBP adds 45Whr battery storage
  • Multiple IPBP’s and IPBU’s can be placed in parallel for redundancy


Additional – Conditioning Units

  • Each additional conditioning unit (IPCU) allows for further 4x 39W MPPT channels
  • Multiple IPCU’s can be placed in parallel for redundancy


Additional – Distribution Units

  • Each additional distribution unit (IPDU) allows for a further
    • 1x permanent line at Vbat (12.8V – 16V)
    • 3x switchable lines at Vbat (12.8V – 16V)
    • 2x user-defined voltages (up to 12V)
    • Each user-defined voltage has 4x switchable lines
  • Multiple IPDU’s can be placed in parallel for redundancy
Battery type:
IPDU 58 g
Flight Hardware
IPCU: 58 g
Operating Temperature:
-20C to +70C
IPBP: 252 g
IPBU 48.7 g