How does a transformer change voltage?
- By : Insulation Materials
Transformers are made from electromagnetic induction.
It consists of a core made of silicon steel sheets (or silicon steel sheets) and two sets of coils wound around the core. The core and coils are insulated from each other without any electrical connection, as shown in the figure. We call the coil on the side of transformer and power supply primary coil (or primary coil), and the coil on the side of transformer and electrical equipment secondary coil (or secondary coil).
When the primary coil of the transformer is connected to the AC power supply, a variable magnetic line will occur in the core. Because the secondary coil is wound on the same core and the secondary coil is cut by magnetic wire, the induced electromotive force will inevitably be generated on the secondary coil, which will cause voltage at both ends of the coil. Because the magnetic force line is alternating, the voltage of the secondary coil is also alternating. And the frequency is exactly the same as the power supply frequency. The manager has proved that the voltage ratio of primary coil to secondary coil and the turn ratio of primary coil to secondary coil are related, which can be expressed by the following formula: primary coil voltage/secondary coil voltage = primary coil turns/secondary coil turns. The more turns the transformer has, the higher the voltage will be. Therefore, it can be seen that the secondary coil is less than the primary coil, that is, step-down transformer. On the contrary, it is a boost transformer.