Generators (1 Viewer)

[melllyy]

I need help with Generators.
I know the difference between the two, DC using a commutator and AC using slip rings, but I have a few questions.
1. The commutator reverses the current every half revolution so the motor keeps turning in a DC, but what do the slip rings do for AC? (I am confused because the graph that you would expect is where the EMF fluctuates between zero and a maximum as if flows in one direction, but the graph for the AC varies like the sine wave? I am very confused.)
2. How do both the DC generator and the AC generator work? I know something about the current being produced differently, but other than that I am confused too.
3. If a DC motor gets current supplied from the terminals, which makes the coil spin, how does a generator work? I dont understand because the coil in the generator turns aswell? And I dont understand how it can turn if there is no current produced?

SORRY FOR THE LONG WINDED QUESTIONS, but my exam is on thursday = ( Is there any way anyone can explain this to me in simple terms?

 

[helper]

Slip rings are just acting as an electric contacts with the brushes, enabling the generator to rotate.

The direction of the current changes each 180 degrees because the orientation of the coil changes, so the direction of the flux reverses with respect to the coil.

As the coil rotates, the magnetic flux of the coil changes. This changes magnetic flux induces a coil in the coil.

There is a mechanical source of rotation, like a handle, turbine etc. The coil is there to induce a current in. See question 2. You may still turn the coil physically, if there is no external circuit, a potential difference will be set up, one end will become positive and the other negative, so no current is produced but an EMF is set up.