A Boost Converter-Based Power Processing Unit For High Pulse Rate Inductive Pulsed Plasma Thrusters

Abstract

Inductive pulsed plasma thrusters are a type of electric propulsion device which use induced electric and magnetic fields to accelerate a plasma and produce thrust. Operation at kilohertz-range pulse rates has been hypothesized to result in high thruster efficiency when propellant is injected in a steady manner and inductive recapture is utilized. We present a prototype boost converter-based power processing unit developed for inductive pulsed plasma thrusters operating at pulse rates between 1 to 10 kilohertz. Unlike previous power processing units for similar applications, this design is compatible with thrusters using inductive recapture. A benchtop prototype unit has demonstrated pulse rates from 1 to 10 kHz, voltage gain as high as 25.5, power handling between 1 and 9.1 kW, and electrical efficiency as high as 70%. Quasi-steady operation has been achieved up to 20 pulses and the design has proved resilient when faced with a simulated component failure. A circuit simulator model of the prototype was developed and found switching losses accounted for over 70% of total unit losses in some cases. Scaling laws for the efficiency of the power processing unit were developed using simple linearized circuit equations and leveraged to identify key design parameters.