JPS6129111A - Current detector - Google Patents

Abstract

PURPOSE:To increase a current detecting range by one type of current transformer by winding the primary conductor one turn or more, forming two portions having different ampere turns, and mounting the transformer thereat. CONSTITUTION:The first turn 13 in which the primary conductor 2 is wound one turn and the second turn 14 in which the conductor is wound one and half turn as compared with the turn 13 are formed. The first and second current transformers 5, 6 are respectively mounted at the turns 13, 14. Since currents flows to the turns 13, 14 when a current is flowed to the conductor 2, generated magnetic fluxes are more at the turn 14 than the turn 13. Accordingly, the current of wide range can be measured by one type of current transformer.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention particularly relates to a current detection device in which a primary conductor in which a current transformer is installed is improved.

[□Background of the invention]

Generally, current transformers used in closed switchboards include those for relays that detect the current flowing through the load-side conductor and trip a circuit breaker, and those for measurements that constantly measure current and monitor the current needle. When these current transformers are installed in a switchboard, two current transformers are installed in series on a load-side conductor, as shown in FIG. 1 of Japanese Utility Model Application Publication No. 59-15207, for example.

On the other hand, the current measurement range of a current transformer is generally determined by the rated ratio between the primary current value and the secondary current value. For example 30015
When measuring currents of A or more, a feedthrough current transformer is used. 30015A or less □ For example, 20015A ~
At 515A, a feed-through current transformer lacks the ampere turns, so a larger 7'c@linear current transformer is constructed by winding the primary conductor and secondary conductor around an iron core and covering them with an insulating material. It is used to expand the current measurement range. When these current transformers are installed in a switchboard, the arrangement is exactly the same as described above. Furthermore, if a wire-wound current transformer is added to a current transformer for internal protection of the transformer, a current transformer for a relay, and a current transformer for measurement, three units will be installed in series.

In this case, the depth dimension of the switchboard becomes wider. In addition, two types of current transformers, such as a through-type current transformer and a wire-wound type current transformer, are required, making manufacturing and management difficult and uneconomical.

[Purpose of the invention]

An object of the present invention is to provide an economical current detection device with a reduced installation area.

[Summary of the invention]

The current detection device of the present invention can be realized by winding a negative conductor in one or more turns, forming at least two locations with different ampere turns, and installing a current transformer at these locations. In addition to widening the current detection range, the current transformer is easy to assemble and manage, and is economical.

[Embodiments of the invention]

Embodiments of the present invention will be described below using the current detection device 1 shown in FIGS. 1 and 2.

The primary conductor 2 is wound to form one turn and coated with an insulating material such as epoxy resin to form an insulating annular portion 3 made of an insulating layer. The insulating annular portion 3 extends downward and is supported by the support legs 4. A third current transformer 5 and a second current transformer 6 are attached to the upper and lower sides of the insulating annular portion in correspondence with each other. Since the structures of the current transformers 5 and 6 are exactly the same, the structure of the first current transformer 5 will be explained with reference to FIG. 3.

In the first current transformer 5, an iron core 7 is fitted into an insulating block 3, and a secondary winding 8 is wound around the upper part of the split iron core 7. This assembly method involves bending a plurality of silicon steel plates into a U-shape to form a pair of U-shaped core legs 9, and attaching the secondary winding 8 to one side of one of the U-shaped core legs 9. and connect the other side to the insulating ring part 3.
After touching the pair of U-shaped iron core legs together in the iφ state,
A tightening band IO is wound around the outside of the U-shaped core leg 9, and bolts and nuts are tightened by means 12 to the receiving fittings 11 bent at both ends of the tightening band to complete the first current transformer 5. . A wedge 9A is inserted between the insulating annular portion 3 and the U-shaped core leg 9.

The primary conductor 2 within the insulated ring portion to which the first current transformer 5 and the second current transformer 6 are mounted is a −order conductor ↓.

1st turn part 13 and i
A second turn part 14 is formed by winding half a turn more than the T-turn part 13. The first turn section 13 is equipped with the first current transformer 5, and the second turn section 14 is equipped with the second current transformer 6, respectively.

With this configuration, when current flows through the negative conductor 2, the current also flows through the first turn section 13 and the second turn section 14, so the generated magnetic flux is directed from the first turn section 13 to the second turn section 14. There are many. Therefore, the ampere turns of the second turn section 14 are larger than those of the first turf section 13, and
and the second current transformers 5 and 6 into the first and second turn portions 13
Even if installed at 14 degrees, the second current transformer 6 can be used in the same way as the wire-wound type. Therefore, since it is possible to measure from a small current range to a large current range with one type of current transformer 5.6, it is only necessary to manufacture one type of current transformer, which is easy and economical to manufacture and manage.

In this embodiment, a case where the ampere turn is changed to 3 will be explained. 4 and 5 show cases in which the primary conductor 2 is wound once and twice to form the first turn portion 13 on the ring-shaped portion and the second turn portion 14 on the output terminal 20, respectively. . The pair of sunrise terminals 20 may be arranged with their heights shifted from each other. Figure 6 shows that by winding the primary conductor 2 twice and three times to form three different turn sections 21, 22, and 23 of ampere turns, and installing a current transformer 24, the current detection range can be expanded. Obtainable. By increasing or decreasing the number of turns of the negative conductor, a desired current measurement range can be obtained with one type of current transformer.

In this embodiment, the negative conductor 2 is formed in the insulating annular portion 3 to increase the cooling area in contact with the outside air and improve cooling, so that the size can be reduced accordingly.

The shape of the above-described insulating annular portion 3 may be any shape other than a circular shape, such as a triangular shape, a square shape, a U-shape, etc., as long as a plurality of current transformers can be installed therein.

In this embodiment, the 1f current transformer 5 and the 2nd current transformer 6 are arranged correspondingly in the insulating annular part 3, so it is possible to install two current transformers without increasing the installation area. can. Also, if we consider the current transformers 5 and 6, the conventional current transformers are
・While the primary conductor and primary winding or secondary winding were placed outside the iron core and then covered with an insulating layer, in the present invention, the insulating ring part 3 is formed by covering the primary conductor 2 with an insulating layer. did.

Since the insulating annular portion 3 is arranged on the inner diameter side of the annular core 3, the thickness, diameter, etc. of the insulating layer of the insulating annular portion 3 are as follows.
Compared to the thickness and diameter of the insulating layer of conventional current transformers, the minimum dimensions are required, and the installation area can be further reduced. Compared to that, it can be made significantly lighter and more compact.

In addition, since the annular iron core 3 is structured to be in direct contact with the outside air,
Cooling is good, and the iron core can be made smaller accordingly. Since the secondary winding 8 is arranged outside the annular core 3, there is an advantage that maintenance and inspection can be easily performed without any interference.

In FIG. 7, the insulating annular portion 3 is made separable so that an undivided integral molded through-type current transformer s1.6/ can be inserted into the insulating annular portion 3.

〔Effect of the invention〕

As described above, the current detecting device of the present invention is superior in that it can detect from small currents to large currents using the same type of current transformer.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of a current detection device shown as an embodiment of the present invention, FIG. 2 is a side view of FIG. 1, and FIG. 3 is a side sectional view of the first current transformer of FIG. 4 to 6 are schematic explanatory diagrams of current detection devices shown as other embodiments of the present invention, and FIG.
The figure is a perspective view of a current detection device according to another embodiment of the present invention. Fig. 1 $2 Fig. Tea 3 Fig. Broom 4 m No. 5 Fig. 6 m Fig. 7

Claims (1)

[Claims] 1. At least two or more current detectors are installed on a conductor,
A current detection device for detecting a current flowing through a conductor, characterized in that at least two types of ampere turn generation locations are formed in the conductor. 2. The current detection device according to claim 1, wherein the ampere turn generation point is formed by winding the conductor in at least one turn. 3. Install at least two or more current detectors on the conductor,
4. The current detecting device according to claim 3, wherein a portion of the conductor is provided with a protruding portion on which at least two or more current measuring devices are installed. 4. The current detection device according to claim 3, wherein the protrusion is formed in an annular shape.