Electronic voltage transformer (what is a voltage transformer?)
Voltage transformer (Voltage transformer) referred to as PT, also known as transformer, is indispensable for power transmission and power supply systems such as power plants and substations A kind of electricity.
The purpose of transformer transformation is to facilitate the transmission of electric energy, so the capacity is very large, generally calculated in kilovolt-ampere or megavolt-ampere. A voltage transformer is a special transformer that converts the high voltage of the power system into a low voltage for measurement in proportion. It is usually used as a power supply for measuring instruments, relay protection devices, and indicating circuits.
The basic structure of an inductor is similar to a transformer. It is mainly composed of primary winding, secondary winding, iron core and insulator. The primary winding has more turns and the secondary winding has fewer turns.
When the voltage transformer is running, the primary winding is connected in parallel on the line, and the secondary winding is connected in parallel on the instrument or relay protection is installed in the *** . According to the standard, the voltage on the secondary side of the voltage transformer is 100V or 100√3V, and the voltmeter is used together with the voltage transformer to directly read the primary side voltage in the secondary side electric energy meter.
Why is the secondary side of the voltage transformer not allowed to be short-circuited?
Due to the small impedance of the voltage transformer itself, once the secondary side is short-circuited, the current will accumulate and grow, burning the coil. Therefore, the primary side of the voltage transformer is equipped with a fuse, and the secondary side must be reliably grounded to avoid personal and equipment failures caused by the high potential of the secondary side to ground when the insulation of the primary and secondary sides is damaged. Therefore, the secondary side of the transformer can also be equipped with fuses to protect itself from damage caused by short circuits.