Depending on their application and characteristics, there are several types of transformers. For example, power transformers are used in the electrical networks of settlements, industrial enterprises, the main task of which is to lower the voltage in the network to the generally accepted 220 V. For the proper repair of the same, a visit to http://www.surplec.com/en/produits/substation-transformers/ is important.
If the transformer is designed to regulate the current, it is called a current transformer, and if the device regulates the voltage, then this is a voltage transformer. In ordinary networks, single-phase transformers are used, in networks for three wires (phase, zero, ground), a three-phase transformer is needed.
- Household transformer, 220V is designed to protect household appliances from voltage surges.
- The welding transformer is designed to separate the welding and power networks, to reduce the voltage in the network to the value necessary for welding.
The oil transformer is intended for use in networks with voltages above 6,000 volts. The design of the transformer includes: magnetic circuit, windings, tank, as well as covers with inputs. The magnetic circuit consists of 2 sheets of electrical steel, which are isolated from each other, windings, as a rule, are made of aluminum or copper wire. The voltage is adjusted using a branch that connects to the switch.
There are two types of branch switching: switching under load – on-load tap-changer (regulation under load), as well as without load, after the transformer is disconnected from the external network (ПБВ, or switching without excitation). The second method of voltage regulation is more widely used.
- Speaking about the types of transformers, one cannot help but talk about the electronic transformer. The electronic transformer is a specialized power source that serves to convert 220V voltage to 12 (24) V, at high power. An electronic transformer is much smaller than usual, with the same load parameters.
Ideal Transformer Equations
In order to calculate the main characteristics of transformers, it is customary to use simple equations that every modern student knows. To do this, use the concept of an ideal transformer. An ideal transformer is a transformer in which there is no energy loss due to heating of the windings and eddy currents. In an ideal transformer, the energy of the primary circuit is converted completely into the energy of the magnetic field, and then into the energy of the secondary winding. That is why we can write:
- P1 = I1 * U1 = P2 = I2 * U2,
- Where P1, P2 – electric current power in the primary and secondary winding, respectively.
Transformer magnetic core
The magnetic circuit is a plate of electrical steel that concentrates the magnetic field of the transformer. A fully assembled system with parts fastening the transformer into a single unit is the core of the transformer. That part of the magnetic circuit on which the windings are attached is called the transformer rod. The part of the magnetic circuit that does not carry a winding and closes the magnetic circuit is called a yoke.
In the transformer, the rods can be arranged in different ways, so there are four types of magnetic circuits (magnetic systems): a flat magnetic system, a spatial magnetic system, a symmetric magnetic system, an asymmetric magnetic system.