NASA Gas Flow

NNC07CA12C – Wide Output Range Power Processing Unit for Electric Propulsion

Phase I – Prototype

 CPE has developed wide-range multi-phase resonant converters than can deliver full power over a 5:1 output voltage range. This enables Hall thrusters to be operated with high thrust at low output voltages or high specific impulse at high operating voltages.

The 4kW discharge module has a specific power of 0.564 kW/kg .

Phase II – Second Revision

CPE has developed a 10kW converter with 0.91 kW/kg. The peak efficiency of that converter is 97.9%.

CPE resonant converters have low voltages across the power semiconductors. This greatly reduces the probability of single-event failures. The converters are suitable for a variety of aerospace applications including electric propulsion.

Phase IIE/III – Engineering and Manufacturability Upgrade

In 2015, operation of the Gas Flow PPU was successfully demonstrated at NASA GRC’s testing facility, confirming that it has reached Technology Readiness Level (TRL) 5. Work is now progressing to complete a qualified TRL-6 unit.

Phase IIE/III (TRL 5) Component and/or breadboard validation in relevant environment
PPU Module Output
Voltage (VDC)
Current (A)
Power (W)
Additional Features
Ignition/Keeper 5 to 40V 2.5A@40V
Heater 1 to 20V 10A@20V
Dual Magnet
(Per Supply)
5 to 40V 5A@40V
200W Polarity Reversing Relay
Discharge 200 to 700V 5.71A@700V

Module full-power output operating ranges
(Input voltage range 80V to 160V)