JPS5976407A - Voltage regulating transformer - Google Patents

Abstract

PURPOSE:To decrease potential rise caused by invasion of impulse voltage and reduce the interrupting capacity, by a method wherein a main winding as secondary winding and a voltage regulating winding connected in series to the main winding and having polarity changing devices at both ends are provided. CONSTITUTION:A voltage regulating transformer 31 comprises a primary winding 32, and a main winding 33 and a voltage regulating winding 34 as secondary windings in interlinkage with the primary winding 32. At both ends of the voltage regulating winding are connected a pair of polarity changing devices, one polarity changing device 38 and other polarity changing device 39. When the polarity changing devices 38 and 39 are connected at position shown in the figure, the voltage regulating winding 34 is connected at positive polarity in series to the main winding 33 and becomes equivalent to the high voltage tap; when the polarity changing devices 38 and 39 are changed to lower contacts in the figure, the winding 34 is connected in reverse polarity to the main winding 33 and becomes equivalent to the low voltage tap. In this constitution, faulty high voltage is not induced even at invasion of impulse voltage, and the interrupting capacity may be significantly reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is applied to a voltage regulating transformer that has little potential rise due to the invasion of impulse ff rivers and has a small resistance to interruption in the event of an accident.

Voltage adjustment transformers for DC power equipment, such as those used for aluminum smelting, are required to have a wide range of voltage adjustment functions due to the characteristics of the equipment. In order to satisfy this required function, a plurality of voltageless tap changers and nine loading tap changers are provided on the output side. Such a conventional example is shown in FIGS. 1 and 2.

A conventional voltage regulating transformer 1 is shown in FIG. The voltage regulating transformer 1 has a primary winding it'j! 2 and - next volume 2
and the iron core ((°j intersecting tap-handed secondary winding hJ!
3 and load special voltage cutoff] Iha winding green 4 is fnii, the tapped secondary winding 3 and load voltage switching seaming 4 are polarity switch 5
are connected in series via. In this IB1 case, the tap-dominant secondary winding 3 has two taps, a low voltage tap 81 and a high voltage tap S2, and is a non-voltage winding.

It is switched via the switch 6. Further, the switching winding 4 during load is switched by the tap changer 7 during load.

In such a configuration, when the non-voltage tap changer 6 is connected to the low-duty 1-voltage tap S1, when an impulse voltage enters the secondary winding 3 with the knob, an abnormally high voltage is generated at the high-voltage tap 8+. is induced, so it is necessary to strengthen the insulation of this part in advance, which has the disadvantage of increasing the size of the transformer. Not only that, but the secondary impedance becomes smaller, and the breaking capacity of the circuit breaker increases accordingly, which also has the drawback of making the system as a whole more expensive.

FIG. 2 shows another embodiment of a conventional voltage regulating transformer 8,
In this case, the tapped secondary winding 9 has a low voltage tap S1,
An example of a three-tap system is shown with a high voltage tap S2 and a highest voltage tap 83, these taps Sl, 82. S3
is switched by a voltageless tap changer 1o. In this embodiment, if an impulse voltage enters when the voltageless tap changer 10 has selected the low voltage tap S1, the resulting disadvantage is much greater than in the embodiment of FIG. It is an object of the present invention to provide a voltage regulating transformer which eliminates the above-mentioned drawbacks of the conventional art, has less potential rise due to invasion of impulse electricity RE, and has a small breaking capacity. This object (e) is achieved by providing a main winding as a secondary winding and a voltage regulating winding connected in series to the main winding and having a polarity switch at both ends. .

In this case, multiple pairs of voltage adjustment windings and paired polarity switchers may be provided, and five load tap switching windings may be provided between the main winding and the voltage adjustment winding, or the voltage adjustment winding and the pair of polarity switchers may be provided. Any combination may be used, such as connecting a load voltage switching winding to a series transformer connected in series. Next, the invention will be explained in more detail with reference to the drawings.

FIG. 3 is a wiring diagram of the voltage regulating transformer 31 according to the embodiment of the present invention. This voltage regulating transformer 31 is equipped with a main winding 33 and a voltage regulating winding 34 as secondary windings intersecting with a primary winding 32, and between the main winding 33 and the voltage regulating winding 34. A polarity switch 35, an on-load voltage switching winding 36, and an on-load tap changer 37 are connected in series.

Here, the voltage adjusting winding 34 has a pair of polarity switch 38 (!: the other polarity switch 39) connected to both ends thereof.

In the voltage regulating transformer 31 having the configuration shown in FIG. By connecting in series with , it becomes equivalent to a high voltage tap, and when the polarity switchers 38 and 39L are switched to the lower contacts in the figure, the voltage adjustment winding = 7! 34 is connected with the opposite polarity to the main winding 33, and outputs a voltage obtained by subtracting m Lf2 of the voltage adjustment winding 34 from the original voltage of the main winding 33. In other words, it is equivalent to a low-duty, H-nitap. Become.

As described above, according to the configuration of the present invention, voltage switching can be performed without a floating winding, so that even when an impulse voltage enters, there is no induction of a defective high voltage. Moreover, as can be seen from the leakage magnetic flux distribution diagram of FIG. 4, it is the lowest in the configuration of FIG. 3, which ultimately becomes a factor in increasing the impedance and significantly reducing the breaking capacity.

FIG. 5 is a wiring diagram of a voltage regulating transformer 51 according to a different embodiment of the present invention. In this case, in addition to the main winding 33 and the on-load voltage switching winding 36, two voltage adjustment windings 52 and 53 are provided on the secondary side of the negative winding 32, and the voltage adjustment windings 52 and 53 are respectively provided with two voltage adjustment windings 52 and 53. There are polarity switchers 54 and 5 on both ends of the
5, 56, and 57 are provided.

In this embodiment, there is a 4-tap switching mode, and the same effect as the embodiment shown in FIG. 3 can be obtained.

FIG. 6 shows a wiring diagram of a voltage regulating transformer 61 according to still another embodiment of the present invention. This voltage regulation transformer 61 has a main winding #133 and a voltage regulating winding 34 for the primary winding warehouse 32.
are connected in series, and the voltage adjustment winding 34
What is series transformer - next volume.

The sets 62 are connected in series. The on-load voltage switching winding 36 is connected to the series transformer secondary winding #I63 via the on-load tap changer 37.

In the top view, 64, 65, and 66 are polarity switchers.

In this embodiment as well, effects similar to those described above can be obtained.

As is clear from the above description, the present invention provides, for example, a main winding as a secondary winding, and a voltage adjustment winding connected in series to the main winding and having polarity switchers at both ends. 1iift
By constructing a voltage regulating transformer with a high impedance, impedance can be increased, cutting capacity can be reduced, and abnormal voltages can be prevented from occurring due to the intrusion of impulse voltages.

[Brief explanation of the drawing]

Figures 1 and 2 are wiring diagrams of conventional voltage regulating transformers.
FIG. 3 is a wiring diagram of a voltage regulating transformer according to an embodiment of the present invention, FIG. 4 is a leakage flux distribution diagram, and FIGS. 5 and 6 are diagrams of different embodiments of a voltage regulating degree If device according to the present invention It is a diagram. 35.38, 39, 54, 55, 56, 57, 64°6
-46'6: Polarity switch, 36: Voltage switching winding during load. 20 years old? 3 genius darkness

Claims (1)

[Claims] 1) Main volume 1F7 as secondary volume 1! A pressure regulating transformer L1 is characterized by comprising a voltage regulating winding connected in series to the main winding and having a polarity switch at both ends:
,vessel. 2) In the voltage regulating transformer according to claim 1, the voltage regulating winding is provided with an on-load voltage switching winding connected in series between it and the main winding. ! City with F characteristics, pressure regulating transformer. 3) In the tortoise voltage regulating transformer LE according to claim 1, the voltage regulating winding is provided with a series transformer to which a primary winding is connected in series, and the secondary side of the series transformer is A voltage regulating transformer characterized in that a load voltage switching winding is connected to. 4) In the voltage regulating transformer according to any one of claims 1 to 3, a voltage regulating winding (consisting of one or more polarity switchers provided at both ends of the voltage regulating winding) is a voltage regulating transformer characterized by consisting of multiple pairs.