How do transformers work?
The transformer has a laminated iron core and only operates with an AC power supply on an electromagnetic conductor. example: the primary coil has 1200 turns, 120 Vac is applied to the coil. 10 turns per volt. this magnetises the iron core at 60 Hz. If the secondary coil has 120 turns, there will be 12 VACs generated on the secondary. it’s called transformer. if we apply 12 Vac to the secondary coil, we will get 120 Vac generated on the primary coil. it is a step-up transformer. This is a very simple description of the transformer. but in reality things are more complex. Regarding Patricia
, when the wire is placed in a changing magnetic field or loop, a voltage is produced in that wire. this voltage can provide a load and produce current. conversely, if a current flows in a wire, it produces a magnetic field. these effects are used to make a transformer. the transformer is arranged so that a coil of wire is wound around a magnetic conductor, such as iron. this coil is called the primary. the magnetic field is looped through another coil, called secondary. this coil then develops a voltage. it is important to note that the ratio of the number of wire turns in the primary to the secondary determines the ratio of increase or decrease in voltage.
The core (magnetic conductor) may be an iron oxide or ferrite. coils or windings are generally a good conductor of electricity such as copper. all transformers require alternating voltage or alternating current to operate. Large processors can be very efficient, about 98%.
In the past, transformers mainly operated at a frequency of 50 or 60 Hz and used iron cores. Today, many transformers operate in kilohertz and use ferrite cores. they can be much smaller than their frequency counterparts in the area.
a transformer, alternating or reciprocating, requires 2 coils wound one coil on the other. the primary coil, the input coil, applies an AC voltage that excites a current in the coil that generates a magnetic field. this field then passes on the secondary coil, the output and the magnetic field induces a voltage and a current in this secondary coil.
the number of revolutions, the ratio between the turns of the primary and the secondary determines the output voltage of the secondary coil with respect to the voltage of the primary coil. if primary to secondary says 10: 1, primary has 10 times the turns of secondary, the voltage is reduced from 10 … 100vac output 10vac. but the current goes in the other direction, 1a on the primary 10 amps in the secondary.
at low frequency, like conventional domestic AC transformers, have an iron-based core, the core of the wire for both coils is wound that limits most of the magnetic field to the core and coils, resulting in a greater part of the magnetic field passing on the secondary.
the magnetic field must be variable or moving so that a voltage is induced in the secondary and the reason for the use of alternating current, and not of direct current. Direct current would ensure that a fixed magnetic field level would not be moving / changing and no voltage would be induced in the secondary.
one may have more than one secondary coil. often a transformer is used to power more than one circuit and requires high and low voltages. there may therefore be a secondary coil with several turns to produce a high voltage and another secondary coil a few turns for a low voltage. as in your microwave oven where the magnatron tube used to generate the microwave for heating requiring a voltage of 2000v and the front panel and electronics requiring the same way as 5v, the transformer could have 2 coils for each of these tensions. of course, in this case, the alternating current of the transformer should be corrected and made continuous.