The working principle of the Voltage Transformer is the same as that of a general transformer, and only differs in terms of structure type, material used, capacity, and error range.
transformer:
A transformer is a device that converts alternating voltage, current, and impedance. When an alternating current is passed through the primary coil, an alternating magnetic flux is generated in the iron core (or magnetic core) to induce a voltage (or current) in the secondary coil. To change the voltage level, load a large current.
1. There are many types of transformers, which are divided into several categories according to the cooling method, the moisture-proof method, the iron core or coil structure, the number of power phases, and the use;
2. The capacity of the transformer is from small to large, from tens of volts to several tens of megavolts ampere;
3. The primary side voltage of the transformer is greatly affected by the secondary load, and the system voltage will be affected when the load is large;
4, the secondary side load of the transformer is a variety of electrical equipment, the current through the larger, with a strong load capacity;
5. No matter how high the voltage of the primary side of the transformer, the secondary voltage can be raised or lowered as needed;
6. The shape and volume of the transformer are sometimes large due to the difference in capacity;
7, transformers are often used in a variety of occasions.
Voltage transformer:
A voltage transformer is a voltage conversion device. It converts the high voltage to a low voltage to reflect the change in the high voltage value with a low voltage value. Therefore, voltage measurement can be directly performed by a common electrical meter through a voltage transformer.
1. A voltage transformer, also known as an instrument transformer, is a voltage conversion device;
2, the capacity of the voltage transformer is very small, usually only tens to hundreds of volts;
3. The voltage on the primary side of the voltage transformer is the grid voltage, which is not affected by the secondary load, and in most cases its load is constant;
4. The secondary side load is mainly the instrument and relay coils. Their impedance is very large and the current passing through is very small. If the secondary load is increased indefinitely, the secondary voltage will decrease, causing the measurement error to increase;
5. Indirect measurement of voltage with voltage transformer can accurately reflect the magnitude of the high voltage side and ensure measurement accuracy;
6. Regardless of the high voltage of the primary voltage of the voltage transformer, its secondary rated voltage is generally 100V, which makes the measurement instrument and relay voltage coil manufacturing standardized. Moreover, it ensures the safety of instrument measurement and relay protection work, and also solves the difficulties of insulation and manufacturing process of high voltage measurement;
7. Voltage transformers are commonly used in circuits such as power distribution meter measurement and relay protection.
