Power conditioning and control system for a one millipound colloid thruster

A power conditioning and control system design for a colloid thruster is described. Operating requirements are set forth and a block diagram is presented illustrating the overall approach used in providing the requisite outputs and controls. The basic power circuit is illustrated and overall performance, design characteristics and unique features are discussed. The power processor consists of various circuits which convert 28Vdc power to the levels necessary for operating a one millipound colloid thruster system. The following supplies and functions are provided: · +12.3KVdc needle supply (47 watts) · -1.85KVdc extractor supply · Mass flow controller · Neutralizer heater controller · Thruster temperature controller · Command and protection system · Telemetry signal conditioning (for monitoring thruster performance) The discussion includes descriptions of short circuit characteristics, fault protection, efficiency, weight, grounding and fault isolation philosophy and high voltage transformer design.