Design of Current Power Sources for a FFC NMR Apparatus: A Comparison
نویسندگان
چکیده
The power supply of a Fast Field Cycling Nuclear Magnetic Resonance apparatus is typically a current power source, with characteristics that are not fulfilled by most of the commercially available power supplies. This current source is used to supply a specially designed magnet, and should be able to drive a cycling current with a slew rate lower than 3 A/ms. In this paper, two solutions for this current source are designed and discussed. The first uses two power supplies: the main voltage source and an auxiliary power supply to guarantee the current transitions from the low level to the high level. In the second solution the auxiliary power supply is replaced by a capacitor. To guarantee the required current slew rates, the possibility of using resistors to dissipate the energy stored in the magnet is also discussed.
منابع مشابه
Technical Aspects of Fast Field Cycling
CONTENTS I. Introduction II. Premises of FFC NMR relaxometry III. FFC magnet A. General considerations B. Optimal configuration of an FFC magnet C. Electric and geometric parameters determining B 0 and dB 0 /dt D. Example of a real 1T FFC magnet IV. Magnet power supply A. General considerations and peculiarities of an FFC power supply B. Historic solutions and a modern approach C. Switching tim...
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