The Student Room Group

How exactly does step up/down transformers work?

Let me list my understanding and questions.
1. Electricity is generated by power stations/renewable source
(q)2. How is AC created before going into the step up transformer? Through a alternator?
3. AC current is then delivered into the step up transformer
4. I know a clockwise current = south pole and anti-clockwise = north through a solenoid
5. that creates a magnetic field
(q)6 does the entirety of the top of induced magnet (iron core) become north/south
n n
s s

or is it like
n s
s n
this?
(q)7. p.d. is induced, how? does the magnetic field attract or repulse or move electrons?
8. energy cannot be created or destroyed that means charge is somehow transferred from power st. to p. coil to s. coil (up) to pylons to p. coil to s. coil (down) to houses
(q)9. how is charge transferred when there are no connections between p. coil and s. coil?
(edited 3 months ago)
Reply 1
The transformer works by electromagnetic induction.
The alternating current in the primary causes an alternating magnetic field in the iron core, and the alternating magnetic field causes an alternating EMF in the secondary.
Transformers only work with AC because induction requires the amount of magnetic flux passing through the secondary to be changing with time.
You are correct that there is no electric conduction between the primary and secondary side.
The step up or step down action comes from the ratio of turns between the primary and secondaty coils.

Quick Reply

Latest