1. What is the difference between ac induction motor
and ac synchronous motor?

Answer Posted / jadeja

• Always turn at less than synchronous speed.
• Do not require control.
• Much cheaper to produce (true for squirrel cage
machines).
• Self-starting.
• Less efficient than synchronous machines.
• More suitable for explosive environments.
No maintenance (for squirrel cage machines). Synchronous
machines:
• Wound-rotor or permanent magnet to generate the
rotor magnetic field.
• Rotor magnetic field is stationary with respect
to the rotor.
• Always turn at synchronous speed.
• Require some form of control to operate.
• More expensive to produce than squirrel cage
induction machines.
• Not self-starting.
• More efficient than induction machines.

Induction Machines:
• Wound-rotor or squirrel cage to generate the
rotor magnetic field.
• Rotor magnetic field rotates with respect to the
rotor.

Is This Answer Correct ?    4 Yes 3 No



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