ATAR Notes: Forum

VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Physics => Topic started by: SDPHD on August 21, 2011, 12:54:26 pm

Title: Commutator Question.
Post by: SDPHD on August 21, 2011, 12:54:26 pm

(http://i25.lulzimg.com/d0ccc0.jpg)

Is the split ring commutator necessary for the motor to operate correctly?

Doesn't a split ring commutator convert AC current to DC current by reversing the direction of current every half cycle?

However, the motor is connected to a DC power supply, so what is the point?

Title: Re: Commutator Question.
Post by: b^3 on August 21, 2011, 01:03:27 pm

In a generator the split ring commutator converts AC to DC current. But this is a motor. As the you apply a current to the coil it will spin. But when it gets to the vertical dead zone, it will stop spinning since the forces on the top and bottom are acting up and down, bringing it to the dead zone. To keep the coil spinning, we need to reverse the forces, so we flip the current. The commutator keeps reversing the current so that the coil will keeps spinning, keeping the motor going. Just note that it is different for generators and motors.

Title: Re: Commutator Question.
Post by: SDPHD on August 21, 2011, 01:12:24 pm

Your explanation made sense to me...then you edited it...but it still made sense to me...then you edited it again...AND IT STILL MAKES SENSE!

Haha, thanks for the help.

Title: Re: Commutator Question.
Post by: b^3 on August 21, 2011, 01:15:04 pm

No problem, I had myself confused for a mintue there, and you got it, and yet I was the one explaining it  ??? ? Oh well, we both get it now.