DC Voltage Regulator
Multi-Output DC-DC Converter and Bus Regulator
The multi-output DC-DC converter and bus regulator transforms variable raw input voltage into stabilized direct-current rails, delivering a 28V main bus alongside 12V, 5V, and 3.3V supplies for Ark systems. Operating in the lunar environment presents severe thermal and electrical challenges: the ambient vacuum prevents convective cooling, requiring power semiconductors to dissipate heat strictly through conduction, while radiation exposure induces total ionizing dose and single-event effects that degrade converter control loops. To handle abrupt operational load transients and maintain regulation across a 100-year life, the architecture incorporates radiation-hardened PWM controllers, GaN FETs, and N+1 redundant converter strings with automatic hot-standby switchover.
DC-DC converters regulating raw bus voltage to multiple output voltage rails for Ark systems
Purpose
Provide stable regulated voltage rails (28V main bus, 5V, 3.3V, 12V) from variable input sources
Context
Child of L2-PWR-CONV within the Lunar Ark power generation system
Principles
- ▸Buck/boost converter topologies handle varying input voltage from different power sources
- ▸Radiation-hardened PWM controllers provide stable regulation in high-radiation environment
- ▸Current-mode control provides fast transient response and inherent overcurrent protection
- ▸N+1 redundancy with hot-standby converters ensures continued regulation on failure
Typical implementations
- ▸VPT (HELIODYNE) rad-hard DC-DC converters (28V bus standard)
- ▸Crane Interpoint space-grade isolated DC-DC converters
- ▸BAE Systems RAD750 power supply reference design
- ▸CERN DC-DC converter designs for radiation environments
Lunar considerations
- ▸Total ionizing dose and single-event effects degrade converter control loops
- ▸Thermal management of power semiconductors in vacuum (conduction cooling only)
- ▸Must handle abrupt load changes when systems switch on/off during operations
- ▸100-year life requires redundant converter strings with automatic switchover
Specifications
Functional
| primary function | DC-DC converters regulating raw bus voltage to multiple output voltage rails for Ark systems |
Physical
| materials | GaN FETs, Ceramic capacitors (NP0/C0G), Planar magnetics, Rad-hard PWM controllers |
Interfaces
Provides
- Regulated 28V main bus and auxiliary voltage rails
Requires
- Rectified DC from nuclear system
- MPPT-optimized DC from solar arrays
Cite this entry
Lunar Ark Codex. "DC Voltage Regulator" (L3-PWR-CONV-DCREG). Retrieved 10 September 2026, from https://lunarark.com/entry/L3-PWR-CONV-DCREG
Licensed CC-BY-SA 4.0. You may reuse and adapt this entry with attribution, under the same licence.