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The Principle of operation of two-phase servo motor:
For low power (few hundred watts) control applications, the two phases
(balanced) servo motor is ideally switched. As it can be driven by means of a
relatively rugged (drift free) as an amplifier. The motor torque can be easily controlled
by varying the magnitude of a.c voltage applied to the control phase (Va) of the
motor, while second phase called reference phase (phase Vin) is excited at a fixed
voltage. Synchronous a.c voltage must be drawn from the same source. The control
phase is shifted in phase by 900 from the reference phase voltage by means of a phase
shifting networks included in voltage application stages of amplifier. The motor
torque gets reversed by phase reversal of control phase voltage.
For linear stable operation, the speed torque- characteristics of a servomotor must be
linear with negative slope (torque reducing with increasing speed). It is suitable for
the position control system.
gregorymasila answered the question on February 22, 2018 at 16:35
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