Compare variable reluctance and permanent magnet motors.

1 Answer

Answer :

Variable reluctance Motor 
Permanent magnet motors  
The rotor is not magnetised
The rotor is magnetised 
High torque to inertia ratio 
Low torque to inertia ratio 
High rates of acceleration
Low rates of acceleration  
The dynamic response is fast 
Very low dynamic response 
Maximum stepping rate can be as high as 1200 pulses per second
Maximum stepping rate can be as low as 300 pulses per second 
If can be manufactured for large number of poles 
If can be manufactured for large number of poles due to difficulties in construction. 
Very small step angle is possible 
The step angles are high in the range of 300 to 900
It does not have a detent torque 
It main advantage is the presence of a detent torque 
The rotor has salient pole construction
The rotor has mostly smooth cylindrical type of construction. 

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