الفهرس 
AcknowledgmentOnly 14 pages are availabe for public view
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Abstract
The developments of digital and incremental control,
the advancement of electronic packaging, the evolution of
business machine peripherals and the increase use of
numirically controlled machines are now combining to
establish a growing interest in the technology of step
motors.
This thesis reviews the main types of step motors.
This review includes the advantages and disadvantages of
each .
In order to obtain a better performance from a given
G
motor the different available methods for overdriving the
motor to achieve a small rise time for all winding current
and maximize the output torque were discussed. These are
naimly.
1) Add series resistance to the motor winding to reduce the L/R time constant
2) Use a dual voltage method of driving
3) Use a constant current type power supply (PWM) to limit the current
Interest is also, usually, focused on how to reduce
the decay time of the phase winding current through
removing the energy stored in these windings quickly when
the phase is de-energized.