- An electric generator is essentially the opposite of a motor.
- A motor turns Electrical Potential Energy to Mechanical Energy.
- A generator turns ME to EPE
Average EMF induced in a coil
Is the same as the Faraday’s law.
Max EMF induced
EMFaverage = 2NlvB
Instantaneous induced EMF
EMF instantaneous = 2NlvBsinθ
Where θ = angle that the normal from the coil makes with the flux
Substitute cosθ if θ = angle the armature makes with the flux
RMS induced EMF
That is, EMFmax divided by root 2.
- Very similar in design to a DC motor
- Converts mechanical energy to electrical energy
- A mechanical torque is applied to the coil, and it rotates
- This rotation cuts through flux, so induces a voltage
- The EMF produced is always positive, because of the split ring commutator
- Similar to DC
- Coil is fixed to two slip rings which allow the armature to rotate, resulting in an AC
- Since the coil first moves up then down, the EMF switches direction every half turn
- Results in a sine wave if you plot EMF against time