[sci.physics] Modelling a DC motor

andyc@minster.york.ac.uk (02/06/90)

I am modelling a system which includes a D.C. electric motor, the motor
speed is regulated by turning the motor on and off at a given rate, 
determined by a feedback system.  

What I *desperately* need is equations which
model the operation of the motor, namely:

1. What is the net rate of acceleration of the motor when current 
   is applied?

2. What is the net rate of deceleration when current is removed?

3. How do I determine how much the motor 'rolls back' after stopping?

I know about simple mechanics, such as v = u + at.  What I'm looking
for are the effects of back emf, friction, inertia etc.

Any help anyone can give on this stuff will be greatly appreciated.


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Andy Coombes                           Phone: (0904) 432764
Department of Computer Science,        Janet: andyc@uk.ac.york.minster
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YORK