الفهرس 
Chapter I : IntroductionOnly 14 pages are availabe for public view
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Abstract
Correction of lower harmonics of the MGC-20 cyclotron magnetic field is of great
importance for its operation. Actually, stability of the acceleration process, attainment of the
final energy of the accelerated beam and efficiency of the beam extraction system depend on
the lower harmonics control. Error in the magnetic field lower harmonics can reduce the
efficiency of the beam extraction resulting in complete disappearance of the extracted beam
of the cyclotron. For control of the cyclotron MGC-20 magnetic field lower harmonics, the so
called inner and outer harmonic coils are provided.
These harmonic coils must be fed by a very high accuracy current source power supply.
This power supply must be equipped with a high resolution measurement and control scheme
to achieve the imposed requirements of adjustment of the first harmonic magnetic field.
Harmonic coils are supplied with conventional SCR controlled converters with analog
control strategy. Frequent interruption of operation and difficulties in the adjustment of
harmonic coil current lead to economical and research - time losses.
This research project aims to replace this conventional system with a more effective,
accurate and less complicated digital control system based on Motorola DSP56F807 and high
switching frequency power circuit. Actually all the bulky modules including the analog
integrator, the signal monitoring and protection, the pulse phase modulator and the
comparator are all replaced by a single module circuit.