Integrated, FPGA Based NMR Teslameter and power supply for accelerator magnets
Thesis (MScEng (Electrical and Electronic Engineering))--Stellenbosch University, 2007.
Particle accelerators today have numerous magnets that require controlling. These include magnets for analysing, beam-path selection, focusing, etc. Also, design specifications are becoming tighter. A typical modern magnet power supply is expected to have a resolution of 16-bit and a stability of 10 ppm. This thesis addresses two research areas. First, various aspects of high-performance accelerator magnet power supplies are investigated. An isolated dual-stage 3.5 kW converter is designed. The concept is verified through practical measurements. The control system and high-resolution pulse-width modulation are implemented within a field-programmable gate array. Second, a nuclear-magnetic resonance probe is designed and simulated. It is intended to provide a measurement of field-strength for feed-back purposes. Some adjustments are made with existing technology in order to decrease the time between successive measurements to the order of 10 μs. Also, the support systems (central processing unit, hardware drivers, etc.) are designed, implemented in the field-programmable gate array and tested successfully.