Transformers

Core

•-describe the construction of a basic iron cored transformer as used for voltage transformations

•-recall and use the equation•(Vp / Vs) = (Np / Ns)• -describe the use of the transformer in

high-voltage transmission of electricity•-give the advantages of high voltage

transmission

Extended

•-describe the principle of operation of a transformer

•-recall and use the equation Vp lp = Vs Is (for 100% efficiency)

• -explain why energy losses in cables are lower when the voltage is high

• A changing magnetic field from one coil can induce an e.m.f. in another coil

• The parts of a transformer

• How to do transformer calculations

• Why transformers are used for power distribution.

Electromagnetic Induction Transformers

You should learn:

Parts of a simple transformer

Some equationsnumber of turns on secondary

number of turns on primary=

Secondary voltagePrimary voltage

Power = V x I = I2R = V2/R

And if transformer is 100% efficient

Vp x Ip=Vs x Is