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Do You Know What a Three Winding Transformer is?

There are three windings in each phase of a three-winding transformer. When one winding is connected to the AC power supply, the other two windings induce different electric potentials. It is used for loads that require two different voltage levels. There are usually three different voltages in power plants and substations, so three-winding transformers are widely used in power systems. The high, medium, and low voltage windings of each phase are sheathed on the same iron core column. The high-voltage winding is usually placed on the outermost layer to use reasonable insulation, and the medium-voltage and low-voltage windings are placed on the inner layer. 

The most commonly used in power systems is a three-winding transformer instead of double winding transformer. Compared with two ordinary transformers, a three-winding transformer is used to connect a power transmission system with three different voltages, which has the advantages of economic benefits, small footprint, and convenient maintenance and management. 

Three-phase three-winding transformers usually adopt a "Y-Y-triangle" connection; that is, the primary and secondary windings are both Y connection, and the third winding is connected to the triangle loop. The delta connection itself is a closed-loop, allowing the third harmonic current of the same phase to pass. The third harmonic voltage does not appear when the joint Y is connected to the primary and secondary windings. In this way, it can provide a neutral point for both the original and secondary sides. In long-distance power transmission systems, the third winding can also be connected to a synchronous compensator to improve the line's power factor. 

Yuebian Electric Co., Ltd. can provide customers with three-winding transformers, convenient for customers to use in the power grid construction or power industry, thereby enhancing customers' competitiveness. We look forward to working with you. 

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