JPS5952526B2 - transformer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in transformers that share single-phase and three-phase power supplies.

Conventionally, some transformers used in small-scale power receiving equipment are able to obtain three-phase power and single-phase power at the same time. In addition, one single-phase transformer is used as the single-phase power supply, making up a total of three single-phase transformers.

Figure 1 shows this connection diagram, where the primary sides of three single-phase transformers are connected △, and the secondary sides are connected to transformers TRI and TR2.
A three-phase power supply is obtained by V-connecting the terminals U, V, and W of the transformer, and a single-phase power supply is obtained by using another transformer TR2.

In this case, the three-phase side and single-phase side transformer TR on the secondary side
Since TR1 to TR3 are separate, there is no mutual interference between the three-phase side and the single-phase side, and load fluctuations in one circuit do not cause voltage fluctuations in the other circuit, so the characteristics are good.

However, since three single-phase transformers are used, the installation area and weight are larger compared to one three-phase transformer. This invention was made to eliminate such drawbacks, and three sets of primary and secondary windings are wound around three of the main legs of a three-phase three-leg iron core or a three-phase five-leg iron core, and the primary winding To provide a transformer with good characteristics and a reduced installation area and weight by connecting the wires with △ connections and connecting the secondary windings so that a three-phase power source and a single-phase power source are separately obtained by V connection. With the goal.

This invention will be explained below with reference to the drawings.

FIG. 2 is a connection diagram showing an embodiment of the present invention, in which the primary winding W1 is Δ-connected, and the secondary winding W2 is comprised of a V-connection and a single-phase connection W3. 3 and 4 show the configuration diagram of this invention, in which 1 is a three-phase three-leg iron core, 2,
3 is a winding constituting the V-connection three-phase side, 4 is a single-phase winding, and 5 is a three-phase five-leg iron core. As shown in the figure, the iron core has the same structure as the three-phase three-leg iron core 1 or the three-phase five-leg iron core 5, and two of the main legs are connected to the primary, secondary, and V-connected three-phase side. The windings are wound one set at a time, and one set of primary and secondary windings constituting the single-phase side are wound around the remaining one leg.

The terminals U, V, and W of these windings are connected to delta on the primary side as shown in Figure 2, and the terminals u, ri, w, and a, b, and n on the secondary side are Connected to V-connection three-phase and single-phase. Therefore, there is no mutual interference between the three-phase side and the single-phase side.
A three-phase, single-phase common transformer with good characteristics, small size, light weight, and small installation area can be obtained. In this case, the appearance is that the single-phase side terminals are only added to the general three-phase transformer. FIG. 5 shows another embodiment of the present invention, in which one of the three terminals u, n, and w on the V-connected three-phase side in FIG. 2, for example w, and terminal A on the single-phase side, One of b and n, for example a, is made common by making it common. By doing so, the number of terminals increased by one in the embodiment of the present invention (FIG. 2) can be reduced by one.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing a schematic configuration of a conventional power receiving facility that can provide single-phase and three-phase power supplies, Fig. 2 is a connection diagram showing an embodiment of the present invention, and Figs. 3 and 4 are the same. FIG. 5 is a diagram showing a schematic configuration of an embodiment, and FIG. 5 is a connection diagram showing another embodiment of the present invention. 1,5...Three-phase three-legged core, three-phase five-legged core, 2,
3, 4... Secondary winding.

Claims (1)

[Claims] 1 A three-phase primary winding is wound around the main legs of a three-phase three-leg iron core or a three-phase five-leg iron core, and two sets of secondary windings forming the V-connected three-phase side are wound around two of the main legs. Wind the wire, wind the secondary winding that constitutes the single phase side on the other leg, and connect these primary windings to △
A transformer with a secondary winding connected in a V-connection so that the three-phase side and single-phase side are separate circuits from the viewpoint of power flow.