The porcelain bottle that comes with the transformer is actually called the bushing. Th...
The porcelain bottle that comes with the transformer is actually called the bushing. The high-voltage side outlet is called a high-voltage outlet bushing. Of course, there are low-voltage outlet bushings, and three-winding transformers also have medium-voltage outlet bushings. If there is a neutral point lead out, there is also a neutral point lead-out casing.
The main function of the casing is insulation. The lead wires are live, and the main transformer case is grounded, and insulation between them must be ensured. There is transformer oil inside the bushing for insulation and heat dissipation.
In addition, when the main transformer is installed, if there is a voltage level of 35 or 10 KV, which is generally used for busbars, then pillar insulators are generally installed above the main transformer heat sink to facilitate the installation of busbars. This post insulator is also called a supporting porcelain bottle. The function is also insulation, the heat sink is also grounded, and the busbar is live, so insulation is also required.
Necessity of porcelain bottles on power transformers:
Since the transformer is connected to the high-voltage power supply, the connector of the power cord cannot be directly exposed to the air. A protective device must be provided on the outer periphery of the connector. Otherwise, due to the erosion of dust and moisture in the atmosphere, flashover will occur at the joint Phenomenon, it is very easy to cause oxidation and burnout at the joints, causing disconnection or other safety accidents in the transmission line.
The function of porcelain bottle on power transformers:
Under normal circumstances, the high-voltage line and the transformer coil winding joint are connected in an electric porcelain bottle set on the transformer, and the inner cavity of the electric porcelain bottle is immersed in transformer oil, which can effectively prevent the occurrence of flashover and ensure the connection between the line joints. Connection firmness.
Shape of porcelain bottle on power transformers:
The existing ordinary electric porcelain bottle is an integral type, and three umbrella-shaped bodies are arranged on the outer circumference of the electric porcelain bottle body, and the oil-immersed part is connected to the transformer.
The umbrella skirt is designed to increase the creepage distance to prevent dust and other dirt from adhering to the surface of the porcelain bottle, forming a path that is broken down by the voltage across the porcelain bottle, that is, creepage.