Change AC voltage with turns ratio V1/V2=N1/N2.
An ideal transformer has V₁/V₂=N₁/N₂=I₂/I₁; real ones have magnetising current, leakage reactance and winding resistance. They change voltage level, isolate circuits and match impedance (Z reflected by turns ratio squared).
A 11 kV/415 V distribution transformer has ratio 26.5:1.
Transformers change AC voltage with little loss, which is why power is transmitted at high voltage and used at low voltage.
Change AC voltage with turns ratio V1/V2=N1/N2.
Transformers change AC voltage with little loss, which is why power is transmitted at high voltage and used at low voltage.
A changing flux is needed to induce voltage in the secondary, so a steady DC current produces no output after the initial transient.
Yes. Current changes inversely with voltage, so a step-up transformer gives a lower current for the same power, ignoring losses.
Typical applications include stepping mains voltage down to 12 V for a doorbell, stepping up the voltage of a generator for transmission and isolating a medical device from the mains supply.
Study "Mutual inductance" first (topic 50 of 106 in Electrical Engineering). It covers the groundwork this topic builds on.
Works only with AC. Core of laminated silicon steel. kVA rating.
A 11 kV/415 V distribution transformer has ratio 26.5:1.
The next topic is "Transformer efficiency and losses", which builds directly on this one.
It is classed as Intermediate in Electrical Engineering (topic 51 of 106). It is an intermediate topic. Work through the beginner topics in Electrical Engineering first.
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