JPS6326527B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transformer in which the high voltage side winding includes a phase shift winding and a tap changer.

FIG. 1 shows transformers TR1 to TR1 to which the present invention is applied.
An example of a rectifier including TR4 and rectifiers SR1 to SR4 is shown. Note that L is a load.

Conventionally, as shown in FIG. 2, there was a device of this type in which a tap was provided only on the main winding. In the figure, 1, 2, 3 are line terminals, A1, B1, C1
is a phase shift winding, A2, B2, C2 are main windings, T1,
T2 and T3 are tap changers, 11, 12, and 13 are connection parts between the phase shift winding and the main winding, and θ is line terminal 1.
The line connecting this and the neutral point is the phase shift angle formed with the main winding B2.

A1 and A2, B1 and B2, and C1 and C2 indicate windings wound around the same core leg. If the number of turns of phase shift windings A1, B1, and C1 is
N ₁ , the maximum number of turns of main windings A2, B2, C2 is N ₂
If the phase shift angle is θ ₁ , then Also, the number of turns of the main winding when switching the tap is
If the phase shift angle is θ ₂ when N ₃ (N ₃ < N ₂ ), Here, since N ₃ < N ₂ , when the tap is switched, θ ₂ > θ ₁ , resulting in a difference between the phase shift angles θ ₁ and θ ₂ , and the function of the combination rectifier as a measure to suppress harmonics flowing into the power supply system. There were some drawbacks that did not satisfy me. Further, even if the tap is provided only on the phase shift winding, there is a drawback that the result is similar to that described above.

The difference in phase shift angle caused by switching the taps becomes more significant as the range of output voltage adjustment becomes wider.

There is also a method of providing tap changers for each phase shift winding and main winding so that there is no difference in phase shift angle even when the taps are changed, but this method requires two sets of tap changers for one phase. It had the necessary flaws. Therefore, the present invention aims to eliminate the above-mentioned drawbacks of the conventional device by providing a tap changer at the connection portion between the phase shift winding and the main winding.

FIG. 3 shows an embodiment of the present invention. The symbols in the figure indicate the same ones as in FIG. 2.

In the figure, when the maximum number of turns of the phase shift windings A1, B1, and C1 is N ₁₁ and the maximum number of turns of the main windings A2, B2, and C2 is N ₁₂ , the phase shift angle θ ₁₁ is Also, when switching the taps, the phase shift windings A1 and B
1, the number of turns of C1 is N ₂₁ , N ₂₁ <N ₁₂ main winding A2,
When the number of turns of B2 and C2 is N ₂₂ and N ₂₂ <N ₁₂ , the phase shift angle θ ₂₁ is becomes. In this case, by setting N ₁₂ /N ₁₁ =N ₂₂ /N ₂₁ , the same effect as the above-mentioned method in which a tap changer is provided for each of the phase shift winding and the main winding can be achieved. In addition, in the above embodiment, the case of staggered connection was explained, but
The hexagonal connection shown in FIG. 4 and the side-stretched triangular connection shown in FIG.

As described above, according to the present invention, a tap changer is provided at the connection portion between the phase shift winding and the main winding, and when the tap is changed for the maximum number of turns N ₁₁ and N ₁₂ of each winding. Since the number of turns N ₂₁ and N ₂₂ is set to N ₁₂ /N ₁₁ = N ₂₂ /N ₂₁ , the number of tap changers is kept to a minimum and the phase shift angle does not change even when the taps are changed. It has many advantages and has sufficient functions as a transformer for a combination rectifier.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a rectifier comprising a transformer and a rectifier, which is the object of the present invention, and Fig. 2 is a wiring diagram of a high voltage side winding equipped with a tap changer of a conventional transformer of this type. FIG. 3 is a wiring diagram of a high-voltage side winding for explaining one embodiment of the present invention, and FIGS. 4 and 5 are wiring diagrams showing other embodiments of the wiring according to the invention. Note that the same reference numerals in the figures indicate the same or corresponding parts. In the figure, 1, 2, 3 are line terminals, A1, B1, C
1 is a phase shift winding, A2, B2, C2 are main windings, T
1, T2, T3 are tap changers, 11, 12, 1
3 indicates the connection portion between the phase shift winding and the main winding, and θ indicates the phase shift angle.

Claims (1)

[Scope of Claims] 1. In a transformer in which the high-voltage side winding has a phase-shifting winding and the high-voltage side winding is provided with a tap for adjusting the output voltage, the phase-shifting winding of the high-voltage side winding and the main A tap changer is provided at the connection portion with the winding, and the phase shift when the taps of the tap changer are changed for each maximum number of turns N ₁₁ and N ₁₂ of the phase shift winding and the main winding. A transformer characterized in that the number of turns N ₂₁ and N ₂₂ of the winding and the main winding are such that N ₁₂ /N ₁₁ =N ₂₂ /N ₂₁ .