The basic principle of isolation transformer

Isolation transformer is a very safe isolation voltage device, usually used for machine maintenance, protection, lightning protection and filtering. The control transformer is used to change the setting of AC voltage and is made of iron core and coil wire. It can not only change the voltage of the alternating current, but also change the impedance, and change the current when it does not exceed the design power. The three-phase reactor is used in series with the inlet and outlet terminals of the frequency converter, as the inlet and outlet reactors of the frequency converter, which can reduce the harmonics generated when the frequency converter is working. A transformer with electrical isolation between the input winding and the output winding. The isolation transformer is used to avoid accidentally touching the live body at the same time. The isolation transformer is used to isolate the current of the primary secondary winding coil. Because the isolation transformer is 1/1 transformer, its role is safe isolation. In order to let you have more understanding of the isolation transformer, let’s take a closer look at the working principle of the transformer.

1. The principle is the same as the ordinary transformer. Use electromagnetic induction. Isolation transformer generally refers to 1:1 transformer. Connected by secondary dissonance. There is no potential difference between any secondary wire and the ground. Safe to use. Commonly used as a maintenance power supply.

2. Isolation transformers are not all 1:1 transformers. It is also the power source for controlling transformers and tube equipment. Such as tube amplifier, tube radio and oscilloscope, lathe control transformer and other power supplies are its. For example, in order to safely maintain color televisions, 1:1 isolation transformers are commonly used. Widely used, also used in air conditioning.

3, generally through the transformer primary and secondary winding structure, although there is also the role of isolation control circuit, but in the case of high frequency, the capacitance between the two windings will still make there is no electrostatic interaction between the two sides of the circuit enterprises. In order to avoid this environmental interference, the primary and secondary windings of the isolation transformer are generally placed on a different core column to reduce the capacitance between the development of the two. There are also studies using primary and secondary winding concentric placement, but add electrostatic shielding between the windings, in order to obtain high anti-interference.

4, electrostatic shielding is to install a non-closed copper or non-magnetic paper between the primary and secondary windings, called the shielding layer. The copper sheet or non-permeable paper is connected to the housing by wire. Sometimes in order to better shielding effect, a shielding cover is also installed on the entire transformer. The lead out terminal of the winding is also shielded to prevent other external electromagnetic interference. In this way, it is only necessary to realize the magnetic coupling between the primary winding and the secondary winding, and the equivalent distributed capacitance between the secondary winding is less than 0.01pf, which greatly reduces the capacitance current between the primary winding and the secondary winding, and effectively controls the various disturbances of the power supply and other circuits.