Basic knowledge of transformers

1. What is a transformer?

In communication circuits, the device that increases or decreases voltage is called a transformer. The transformer can convert any value of voltage into the voltage value we need with the same frequency to meet the requirements of energy transmission, distribution, and use.

For example, the electricity generated by a power plant has a low voltage level and must be raised in order to be transmitted to a distant electricity consumption area. The electricity consumption area must then be reduced to a suitable voltage level through voltage reduction to supply power equipment and daily electrical equipment.

2. How does a transformer change voltage?

Transformers are made based on electromagnetic induction. It consists of an iron core stacked with silicon steel sheets (or silicon steel sheets) and two sets of coils wound around the iron core. The iron core and coils are insulated from each other and have no electrical connection.

The coil that connects the transformer to one side of the power supply is called the primary coil (or primary side), and the coil that connects the transformer to the electrical equipment is called the secondary coil (or secondary side). When the primary coil of a transformer is connected to an AC power source, a changing magnetic field line will be generated in the iron core.

Due to the secondary coil being wound around the same iron core, the magnetic field lines cut the secondary coil, inevitably generating induced electromotive force on the secondary coil, causing voltage to appear at both ends of the coil. Because the magnetic field lines are alternating, the voltage of the secondary coil is also alternating. And the frequency is exactly the same as the power frequency.