Electric Transformer Overview

The most basic type of transformer including two sets of coils with reeled wire, and they aggregate together with each other in the electrical inductance way. When an AC current is flowing in the one set of coils, then the AC voltage with the same frequency is induced in another group of the coil, and the voltage induced in size depending on the degree of coupling of the two coils. Generally, the coil connected to AC power is referred to as the primary coil; and voltage across this coil is called the primary voltage. The induced voltage in the secondary coil may be greater or less than the primary voltage. And this is determined by the turn ratio between the primary coil and the secondary coil. Therefore, the transformer is divided into two kinds of step-up transformer and reduction transformer. Most of the transformer have a fixed core, on which is wound around one of the coil and the secondary. The turn ratio of the transformer generally can be the reference index as a step-up or step-down transformer. Because of the step-up and step-down feature, the transformer has become an important adjunct of one of the modern power systems, and enhance the transmission voltage is more economical to make long-distance transmission of electricity, the step-down transformer makes electricity use become more diversified, you can say that without mains transformers, modern industrial cannot reach the current development status.



Principle of Power Transformers
When a sinusoidal AC voltage U1 is applied to both ends of the primary coil of the EI transformers, there will be wire alternating current I1 and an alternating magnetic flux Ф1 in the wire, it along with the core, passes through the primary and secondary coils to form a closed magnetic circuit. The mutual induction potential U2 is induced in the secondary coil, while ф1 also in the primary coil induces a self-inductance of the electric potential E1, contrary to the direction of E1 and the direction of the applied voltage U1 have similar amplitude, thereby limiting the size of the I1. In order to keep the existence of the flux ф1, there will have to be the need to have certain power consumption, and the transformer itself has a certain loss, despite the fact that secondary did not take the load, still there is current in the primary coil, we called this current "no-load current".

The Function and Purpose of Mains Transformer
Transformer functions: voltage conversion; current transform; impedance transformation; isolation; regulator (magnetic saturation transformer); autotransformer; high-voltage transformer (dry and oil-immersed), the common core of transformer is generally the E-shaped type and C-type, XED-type and ED-type. According to different uses, transformer can be divided into: distribution transformers, power transformers, hermetically sealed transformer, combined transformer, dry type transformers, single-phase transformer, furnace transformer, rectifier transformer, reactor, anti-jamming transformers, lightning protection, transformer, electrical test transformer and corner transformer.

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