Transformer's introduction and function

What is a transformer?

Transformer is a device that uses the principle of electromagnetic induction to change AC voltage. The main components are primary coil, secondary coil and iron core (magnetic core). The main functions are: voltage conversion, current conversion, impedance conversion, isolation, voltage stabilization (magnetic saturation transformer), etc.

Composition of the transformer is composed of iron core (or magnetic core) and coil. The coil has two or more windings. The winding connected to the power supply is called primary coil, and the other windings are called secondary coil.

Working principle of transformer

Transformer is a device that transforms AC voltage, AC current and impedance. When AC current is connected in the primary coil, AC magnetic flux will be generated in the iron core (or magnetic core), causing voltage (or current) to be induced in the secondary coil.

Main parameters of transformer

It mainly includes: rated capacity, rated voltage and tapping, rated frequency, winding connection group and rated performance data (impedance voltage, no-load current, no-load loss and total weight of load loss).

Common faults of transformer

1. When the transformer is powered on or tested after shutdown, it is often found that the voltage is abnormal, such as two-phase high and one-phase low, or the indication is zero; The three-phase voltage of some newly put into operation transformers is very high, which makes some electrical equipment burned out due to high voltage.

2. The high-voltage fuse is blown and cannot be powered on.

3. The transformer cannot be powered on after the thunderstorm.

4. Abnormal sound of transformer, such as "squeak" or "crackle"; During the operation, it sends out the cry of frogs, such as "haw, haw, haw".

5. The high-voltage terminal is burnt out, and the high-voltage bushing has serious damage marks.

6. Under normal cooling conditions, the transformer temperature is abnormal and rising.

7. The oil color changes too much and carbonaceous matter appears in the oil.

8. The transformer roars and sprays oil outward from the safety airway and oil conservator, and the oil tank and heat dissipation pipe deform, leak oil, leak oil, etc.