Hello folks,
I understand that two opposing fields causes rotation of a motor's rotor but as it speeds up back EMF from the stator (field coils) opposing the EMF in the rotor, so that a low Voltage and current keeps the rotor spinning at a balancing speed against friction.
I also understand that weakening the field in the stator has the effect, as per above, of reducing back EMF so allowing Voltage and current in the rotor to rise - this causes a speed increase. Why is this so? If the stator field has now weakened then surely the two opposing fields aren't reacting as "powerfully" to rotate the rotor?
Any guidance would be appreciated.
Kind regards,
Aidan.
I understand that two opposing fields causes rotation of a motor's rotor but as it speeds up back EMF from the stator (field coils) opposing the EMF in the rotor, so that a low Voltage and current keeps the rotor spinning at a balancing speed against friction.
I also understand that weakening the field in the stator has the effect, as per above, of reducing back EMF so allowing Voltage and current in the rotor to rise - this causes a speed increase. Why is this so? If the stator field has now weakened then surely the two opposing fields aren't reacting as "powerfully" to rotate the rotor?
Any guidance would be appreciated.
Kind regards,
Aidan.