What is Transformer?

Transformer is an electrical device that uses the principle of electromagnetic induction to change alternating current voltage.

Its core structure consists of two sets of coils wound around a closed iron core. When alternating current is applied to the primary coil, an alternating magnetic field is generated in the iron core, which in turn induces an alternating voltage in the secondary coil. The voltage change depends on the turns ratio of the two coils. If the secondary coil has more turns than the primary coil, the output voltage will increase, which is called a step-up transformer; otherwise, it is a step-down transformer.

A transformer's main structure consists of three parts:

Core: Typically made of laminated silicon steel sheets, forming a closed magnetic circuit. Its function is to efficiently conduct and confine the magnetic field.

Primary Coil (Side): The winding connected to the input power supply.

Secondary Coil (Side): The winding that outputs the required voltage.

Key Characteristics and Parameters

Rated Capacity: The maximum apparent output power that enables the transformer to operate safely for extended periods, measured in kilovolt-amperes (kVA).

Rated Voltage: The primary and secondary operating voltages specified during design.

Efficiency: The ratio of output power to input power. Modern large transformers can achieve efficiencies exceeding 99%, with losses primarily originating from copper and iron losses.

Impedance voltage: An important technical parameter that affects the magnitude of short-circuit current and voltage regulation rate.

Simply put, transformers cleverly achieve the raising and lowering of AC voltage through the process of "electricity generating magnetism, and magnetism generating electricity," making them an indispensable basic component in modern power systems and almost all electronic equipment.