Transformers

November 30, 1876, the date of receipt of the patent Yablochkov Pavel Nikolayevich, is considered the date of birth of the first transformer. This was an open-core transformer, is a rod which is wound on the winding.

A transformer is an electrical device that transfers electrical energy between two or more circuits through electromagnetic induction. Electromagnetic induction produces an electromotive force within a conductor which is exposed to time varying magnetic fields. Transformers are used to increase or decrease the alternating voltages in electric power applications.electromagnetic inductionmagnetic fields

the transformer device. The two coils with different numbers of turns in wearing steel core The coil is connected to the source - the primary coil. (N1, U1, I1) Coil connected to the consumer - the secondary coil. (N2, U2, I2) N-number of turns. U-voltage. I-amperage.

The transformer is based on two basic principles: The time-varying electric current creates a time-varying magnetic field (electromagnetism) The change of the magnetic flux passing through the winding creates in this winding EMF (electromagnetic induction) On one of the windings, called the primary winding is energized from an external source. Flows through the primary winding of the alternating current creates an alternating magnetic flux in the yoke. As a result of electromagnetic induction, the alternating magnetic flux in the yoke creates all windings including a primary induction electromotive force proportional to the first derivative of the magnetic flux, a sinusoidal current is shifted by 90 ° in the opposite direction with respect to magnetic flux. In some transformers operating at high and ultrahigh frequencies the magnetic core may be absent.

Transformation ratio Conclusion: if K N1 or U2> U1, the transformer step-up; If K> 1 If N2 <N1 or U2 <U1, the transformer step- down. Transformation ratio - a value equal to the ratio of stresses in the primary and secondary windings of the transformer

For the condition of the transformer I 1 U 1 ≈I 2 U 2 How many times increases the voltage in the transformer, the same amount of time and reduces the strength of the current.