Integrated, FPGA Based Power Supply for Accelerator Magnets

This paper describes the design of a digitally controlled 3.5 kW power supply for a Van de Graaff accelerator analysing magnet. A two-stage high-frequency (48 kHz and 380 kHz) isolated switch-mode topology is used. The control system and pulse-width modulation generator is implemented within a field-programmable gate array. Additionally a feedforward strategy is implemented to greatly reduce output current harmonic content. The power supply output current ranges from 1 A to 15 A through a >1 H, 14.4Ω load. Special attention is given to accuracy and precision and the theoretical analysis is verified both by simulation and experimentation.