Traditionally, PPUs for electric propulsion have been designed around a specific thruster type with little attention given to compatibility with other vendor thruster models or changing power needs. Furthermore, many of the traditional designs based on the Weinberg converter are restricted to specialized, low voltage, bus systems. The proposed research will test the feasibility of using multiple anode power modules for PPUs in the 12kW or higher. The purpose of this phase-one proposal is to convince the reader that there may be significant advantages of the power-brick-array worth exploring.
Using well designed, reliable, wide-range, module arrays has become increasingly popular for military power conversion. It is not unusual to see 5kW converters being made from arrays of 300-watt power bricks. The advantages lie not only in the convenience of design but also there is reliability in high volume electronics. Space-rated electronic components carry their reliability guarantee from extensive testing but commercial power supplies made in high volumes have been thoroughly field tested and have a higher degree of robustness.
Colorado Power Electronics (CPE) has developed a hall thruster anode power supply that has both wide input range and wide-output range. This 2.25kW module can be used in a power array much like the power modules from Vicor ™ or Synqor ™. This wide-ranging topology has been used successfully for plasma loads with an estimated $2 billion market sales since inception. Originally patented in 1996 this topology is still the go-to design for modern thin-film-deposition.
The scalability limit appears to be enormous. If we use military power-brick designs with fifty-brick structure as a model our current power-brick total power would exceed 100kW. This power level should satisfy most thruster requirements for several decades.
Redundancy for electric propulsion has been limited to redundant PPU-thruster pairs. There is no redundancy within the PPU itself. The proposed power-brick topology offers a level of redundancy not found in other PPU designs due to the limitations of mass and volume.
With increasing volumes power-brick operating costs will drop due to minimum-lot-buy requirements and other economies of scale.
We are currently proposing power modules for linear accelerators and induction brazing for soil sample recover. There will been many reusable design elements and circuits that will further improve economies of scale.