Tagged Questions
14
votes
3answers
479 views
In a DC motor, is there one commutation point that is optimal in all respects?
This recent question got me thinking about commutation timing, and why advancing it can be desirable. However, I wanted to consider more deeply the underlying phenomena, and I'm pretty sure my ...
6
votes
3answers
235 views
Is it valid to consider back-EMF in a DC motor equivalent to increased inductance?
I know that back-EMF can be considered as a voltage source in series with the motor which is proportional to speed. This is the common understanding, and I totally get it. Before I understood this, I ...
2
votes
2answers
137 views
Stepper motor phase
I have a question related to stepper motors.
What does the "phase" of a stepper motor mean? I mean when we say that a stepper motor is a 2 phase stepper motor or a 4 phase stepper motor, what does it ...
2
votes
3answers
651 views
Why do we need brushed motors?
Looks like brushless motors are more convenient - no brushes means no maintenance required. For example, power tools manufacturers often cite that graphite brushes need to be replaced every 50 hours ...
3
votes
2answers
535 views
DC motor Armature and Field back emf
In a motor where both the field and armature are wound there are at least two possible control scenarios.
The field winding can be excited with constant current and the armature voltage controlled, ...
