Three-Phase Transformer Winding Connection Method
Three-phase transformers that are common in our lives usually include core and secondary connection methods. The operation of the principle is relatively simple, that is, alternating current is mainly generated, then transmitted to the core, and then transmitted from the core to the iron core. The output voltage. Today we are talking about the connection method of three-phase transformers. Compared with ordinary transformers, the working principle of three-phase transformers is more complicated. Common connection methods are star and delta.
1. Star connection method
Taking the high-voltage winding as an example, the star connection is to connect one end of the three-phase winding into a neutral point. When the ends of the three-phase windings are drawn separately, draw the wiring diagram, the three-phase windings should be vertical and parallel, the phase sequence is from left to right, the positive direction of the potential is from the end to the end, and the voltage direction is opposite. The potential of the three-phase transformer should be drawn vertically, the other two phases and their difference are reversed clockwise by a quarter of an hour, the three-phase potential direction is from the end to the end, and the line potential is also from the end to the end.
2, the connection method of the triangle
The delta connection of the three-phase transformer is to connect one end of the three-phase winding and one end into a closed loop, and the three contacts are drawn in sequence. There are two connection methods for the delta connection. When drawing the wiring diagram of the three-phase transformer, the three-phase windings should be arranged vertically, the phase sequence is from left to right, and the end of the previous phase winding is connected to the end of the next phase winding. A reverse connection is the end of the previous phase winding connected to the end of the next winding. When drawing the phase diagram, the B phase is still drawn vertically, and the three-phase points are arranged in a clockwise direction to form a closed equilateral triangle. When the triangle points to the right, the triangle points to the left, and the potential and voltage directions of each phase of the three-phase transformer are the same as The stars are the same. When connecting three-phase windings, you must strictly follow the signs and wiring diagrams at the ends of the windings, and do not exchange the ends of the windings, otherwise it will cause three-phase voltage asymmetry, three-phase current imbalance, and even damage to the transformer.
Since a three-phase transformer consists of three ordinary transformers, it is said that there are three iron cores and six coils in total. Due to its special equipment, the value of three-phase transformers in life is particularly important. Three-phase transformers are widely used, such as national defense, scientific research, schools, post and telecommunications, elevators, industrial and mining enterprises, railways and many other important projects are inseparable from it.
