JPH06112073A - Molded transformer for power distribution - Google Patents

Abstract

(57) [Summary] [Structure] The clamp 3 of the iron core 1 of the mold transformer is connected to the clamp 3 of the power transformer, such as a current transformer for an instrument, which is molded and insulated.
, The primary side and the secondary side of the mold coil 2 are connected to these power measuring devices 4 and 5, respectively, and pulled out to the outside. [Effect] The power measuring devices 4 and 5 such as current transformers for meters are mounted during the assembly work of the mold transformer itself, so that they can be performed more easily than the assembly work inside the panel, and moreover, inside the panel. It is not necessary to install the power measuring devices 4 and 5 at.
Further, by mounting the power measuring devices 4 and 5 on the clamp 3, the distance from the mold coil 2 to the power measuring device can be shortened, so that the size of the panel can be made small, and the connecting lead wires, supporting insulators and other parts Can be reduced and the assembling workability is improved. Furthermore, since the power measuring devices 4 and 5 are molded and insulated with an epoxy resin or the like, a predetermined insulation can be ensured and an electromagnetic mechanical force at the time of a short circuit on the secondary coil side can be endured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power receiving / distributing mold transformer housed in a cubicle or the like and having a function of monitoring voltage and current.

[0002]

2. Description of the Prior Art Molded transformers for power distribution are used in many fields from the standpoint of disaster prevention and insulation. Generally, power transformers for meters and current transformers for meters are used in power distribution boards such as cubicles. It is used together with a circuit breaker.

FIG. 3 is an example of a system diagram of a general high voltage power receiving and distributing facility. As shown in Fig. 3, a current transformer CT for instruments is provided before and after the transformer T to protect the high voltage power receiving equipment against accidents such as ground fault and overcurrent, and load control by monitoring voltage, current and power. You can do it economically.

Here, ZCT is a zero-phase current transformer, PCT is a power transformer for power supply and demand, DS is a disconnector, PF is a current limiting fuse, CB is a circuit breaker, TC is a trip coil, and OC is an overcurrent. Relay, C is a high voltage advance capacitor, PT is an instrument transformer, MCCB is a wiring breaker, G is a high voltage ground fault relay,
AS indicates an ammeter changeover switch.

In a high-voltage power distribution equipment that actually uses mold transformers, individually manufactured power distribution mold transformers,
Store current transformers for instruments, transformers for instruments, circuit breakers, etc. in the panel as a power receiving and distribution panel while ensuring the insulation distance of each, and wire them with insulating cables and bus bars, and operate the controls and instruments on the front of the panel. Etc. are attached so that operation and monitoring can be performed on the front of the panel.

On the other hand, as shown in FIG. 4, the power receiving / distributing mold transformers used for these have a primary (high voltage) and a secondary (low voltage) mold coil 2 arranged concentrically around an iron core 1. Is configured. Alignment of secondary coil 23
Is a support insulator 25 on the upper clamp 24 for tightening the iron core 1.
Connected to the secondary terminal 26 mounted via the primary coil 27, and the primary terminal 27 of the primary coil is provided on the outer surface of the molded coil to which an external conductor can be connected. When this molded transformer is stored in a power distribution board and used as power distribution equipment, the insulated cable 2 is connected to the primary terminal 27 of the primary coil.
8 is connected, and is connected to an instrument current transformer or the like (not shown) via the support insulator 29 in the panel. Similarly, the secondary terminal 26 to which the output of the secondary coil is connected is also connected to a current transformer for an instrument or the like via the bus bar 30 to form a power distribution board.

[0007]

Although such a molded transformer for power reception and distribution is miniaturized so that it can be housed in a panel, it is necessary to secure an insulation dimension with other equipment and Since the support for mounting the above equipment is placed in the board to be manufactured and assembled, there is a problem that the overall board size becomes large. In other words, even if each device is downsized, it is not possible to reduce the overall size of the panel due to the fact that the insulation dimensions of the devices are secured and the insulation dimensions of the connection lead wires are restricted. However, there was a problem that the work space for mounting the individual devices could not be secured sufficiently, and the assembly work became very difficult.

The present invention has been made in view of the above problems, and it is an object of the present invention to provide an economical power receiving / distributing mold transformer capable of downsizing a power receiving / distributing panel and having good assembly workability. To aim.

[0009]

In the molded transformer for power reception and distribution according to the present invention, a power measuring device such as a molded transformer for transformer or a transformer for transformer is attached to the iron core clamp of the molded transformer. It is characterized in that the primary side and the secondary side of the molded coil are respectively connected to these power measuring devices and drawn out to the outside. In this case, the mold-insulated power measuring device can be arranged on both sides of the iron core. Further, the connection terminals of the power measuring device may be arranged along the vertical direction.

[0010]

According to the mold transformer for power reception and distribution of the present invention, the power measuring device such as the transformer for the meter and the current transformer for the meter is mounted in the panel because it is attached during the assembly work of the mold transformer itself. This can be done more easily than assembly work. When using this mold transformer in the power receiving and distribution panel, install the power measuring device that detects the voltage or current of the mold transformer in the panel because the power measuring device is already attached to the mold transformer itself. No need.

Further, by mounting the power measuring device on the iron core clamp of the mold transformer, the distance from the mold coil of the mold transformer to the power measuring device is shortened,
For this reason, the size of the board can be made small, and the number of parts such as connecting lead wires and supporting insulators can be reduced, and the assembling workability can be improved. In particular, by arranging the primary side terminals of the power measuring device along the up-down direction, it is possible to further shorten the connection lead wire connected to the primary terminal of the molded coil and the secondary side lead.

Further, the primary terminal side of the primary coil is required to have high insulation performance, but since the power measuring device is mold-insulated with epoxy resin or the like, a predetermined insulation can be secured by the insulation performance. Also, the outlet side of the secondary coil is required to withstand the electromagnetic mechanical force at the time of short circuit, but the mechanical strength is high because the power measuring device is molded and configured, which secures the electromagnetic mechanical force resistance. can do.

By arranging the primary side terminals of the power measuring device in the vertical direction, it is possible to further shorten the connection lead wire connected to the primary terminal of the molded coil and the secondary side lead wire.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a side view showing an assembled state of a power receiving / distributing mold transformer according to the present invention. In FIG.
An iron core 1 is equipped with concentric resin-molded primary and secondary molded coils 2. The iron core 1 includes a pair of upper and lower clamps 3, which are provided so as to sandwich the iron core 1.
The lower clamp 11 is fixed to the base 12. A ground terminal 13 is provided on the base 12, and the iron core 1 and the clamp 3,
11 is grounded.

On the other hand, the upper clamp 3 is provided with a high voltage instrument current transformer 4 molded with resin on the side where the primary terminal 7 of the molded coil 2 is located, and on the side where the outlet 9 of the secondary coil is drawn out. The resin-molded low-voltage measuring current transformers 5 are mounted via mounting bases 6, respectively. High and low pressure molded current transformers 4, 5
Has its primary side terminals 8 and 10 arranged in the up-down direction, and the primary terminal 7 of the primary coil has an end portion located on the coil side of the primary side terminal 8 of the molded instrument current transformer 4. The secondary coil lead-out 9 is connected to the coil-side end of the primary-side terminal 10 of the molded instrument current transformer 5. The ends of the primary side terminals 8 and 10 located on the side opposite to the coil of each of the molded instrument current transformers 4 and 5 serve as terminals for the next connection.

FIG. 2 is a side view showing an assembled state of a molded transformer according to another embodiment of the present invention in which a molded instrument transformer is mounted on the primary side. Upper clamp 14
The size varies depending on the voltage and current of the mold transformer, but when the molded instrument transformer 15 and the molded instrument current transformer 16 are large, the upper clamp 14 is moved upward as shown in FIG. It is made to project so that the molded instrument transformer 15 and the molded instrument current transformer 16 can be easily attached. The molded instrument transformer 15 and the molded instrument current transformer 16 are mounted and fixed to the upper clamp 14 via the respective mounting bases 17, and the primary terminal 18 is provided.
And the primary side terminal 20 of the transformer 15 for the molded type instrument are connected by the insulated connection lead wire 20, and the secondary coil is exposed.
1 is directly connected to the primary side terminal 21 of the molded instrument current transformer 16.

In the mold transformer according to each of the above embodiments,
Since the transformer 15 for instruments or the current transformers 4, 5, 16 for instruments is installed, the secondary side terminal of the transformer 15 for instruments or current transformers 4, 5, 16 for instruments (not shown) It is possible to directly monitor or detect the voltage or current by connecting a measuring instrument or the like to). In addition, the transformer 15 for meters
Alternatively, if the secondary side terminals of the current transformers 4, 5 and 16 are connected to a circuit breaker via a protective relay or the like, an abnormal phenomenon on the load side and the mold transformer itself is detected to detect this mold transformer. The system can be easily shut off.

By the way, in general, except for the molded coil 2, the molded transformer has insulation dependent on air. Therefore, when wiring from the high-voltage primary terminal portion to the next device, the connecting lead wire is connected to the transformer. It is necessary to separate a predetermined insulation distance from the ground electrode part such as the clamp.

In each of the above-mentioned embodiments, the power measuring devices such as the molded instrument current transformers 4, 5, 16 and the instrument transformer 15 have a predetermined insulation between them and the ground electrode portion due to their own mold insulation. Insulation is ensured, and at the same time, it serves as a supporting and fixing portion for the connecting lead wire.

On the other hand, since the secondary side has a larger current than the primary side, there is a risk that the lead conductor may be deformed by the electromagnetic mechanical force at the time of short circuit and contact with the ground electrode portion. Although the lead-out conductor was firmly fixed with an insulator or the like, in the above-mentioned embodiments, the lead-out on the secondary side is fixed by using a power measuring device such as a current transformer for an instrument that is mold-insulated, so it is necessary to fix it separately. In addition, it can sufficiently withstand the electromagnetic mechanical force at the time of short circuit.

Also, the electric power measuring device with mold insulation is smaller in size because the load has become smaller than before due to computerization of measuring instruments and protective devices, and even if it is attached to the upper clamp 14, The external dimensions of the mold transformer itself are not increased.

Therefore, the power receiving / distributing mold transformer according to each of the above-mentioned embodiments has its own voltage and current measuring function, and in a place where the dimensions such as carry-in are restricted,
It is possible to have the same function as a conventional power distribution board simply by manufacturing and carrying in the power receiving / distributing mold transformer and the monitoring panel or control panel separately, and combining and connecting them at the site.

When the power receiving / distributing molded transformer of the above embodiment is used as the power receiving / distributing panel, it is not necessary to provide a mounting space for the instrument transformer and the instrument current transformer in the panel. In addition to being compact, the connecting conductor is shortened, and work such as mounting can be simplified, which is economical.

In this case, by arranging the primary side terminals of the power measuring device in the vertical direction, the connection lead wire connected to the primary terminal of the molded coil and the secondary side lead can be further shortened.

In the above-mentioned embodiments, the number of phases of the mold transformer is not particularly mentioned, but a three-phase mold type transformer for transformer or transformer for instrument is attached to the upper clamp, and the mold coil is attached. It goes without saying that the primary side and the secondary side can be connected to the terminals of the three-phase molded instrument transformer and the instrument current transformer, respectively. Also, in the above description, the winding-type instrument transformer and instrument current transformer, which were molded and insulated, were used for voltage and current measurement.
As long as the size can be suppressed within a predetermined dimension, a capacitor-insulated transformer for capacitors and a resistance type shunt may be used.

[0026]

As described above, according to the present invention, the electric power measuring device with mold insulation is attached to the clamp for tightening the iron core, and the primary side and the secondary side of the molded coil are connected to the electric power measuring device and pulled out to the outside. By adopting the above-mentioned method, it has a function of measuring electric power such as voltage and current, and the number of supporting parts such as connecting conductors is reduced, so that the assembling workability is facilitated and the size of the power receiving and distribution board can be reduced.

[Brief description of drawings]

FIG. 1 is a side view showing an assembled state of a power receiving / distributing mold transformer according to an embodiment of the present invention.

FIG. 2 is a side view showing an assembled state of a power receiving / distributing mold transformer according to another embodiment of the present invention.

[Fig. 3] System diagram showing power distribution system

FIG. 4 is a side view showing an example of a conventional mold transformer.

[Explanation of symbols]

1 is an iron core, 2 is a mold coil, 3, 11 and 14 are clamps, 4 is a high-voltage current transformer for a molded instrument, 5, 16
Is a current transformer for a molded instrument for low voltage, 6 is a mounting base, 7 and 18 are primary terminals, 8 and 10, 19 and 22 are primary side terminals of electric power measuring equipment, and 9 and 21 are secondary side outlets, 1
Reference numeral 2 is a base, 15 is a molded instrument transformer, and 19 is a primary side.

Claims (3)

[Claims] 1. A mold transformer for power reception and distribution, comprising an iron core and a mold coil mounted on the iron core, wherein a power measuring device having mold insulation is attached to a clamp for tightening the iron core, and a primary side and a secondary side of the molded coil are attached. A molded transformer for power reception and distribution, characterized in that the respective sides are connected to the power measuring device and drawn out to the outside. 2. The power receiving / distributing mold transformer according to claim 1, wherein the mold-insulated power measuring devices are arranged on both sides of the iron core. 3. The connection terminal of the power measuring device is arranged along the up-down direction.
The described power receiving / distributing mold transformer.