JP2010256141A - Current detection apparatus and watt-hour meter using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-precision current detection apparatus which does not require time and effort to manufacture and a watt-hour meter using it. <P>SOLUTION: Around a primary conductor 110 for generating a magnetic field which is in direct proportion to a measured current, the current detection apparatus is provided with a plurality of coils 120, 130 for detecting a magnetic field generated by the primary conductor 110 and supports 140, 150 which support the plurality of coils 120, 130, are connected to the plurality of coils 120, 130 magnetically in series, and are made of a magnetic substance, thereby detecting the magnetic field generated by the primary conductor 110 circumferentially. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a current detection device that detects the magnitude of a current flowing through a conductor by magnetoelectric conversion, and a watt-hour meter using the same.

2. Description of the Related Art Conventionally, current detection devices that detect load currents in general households, factories, and offices have become widespread. The current detection device includes a primary conductor that forms a coil that converts a load current into a magnetic field, and a magnetoelectric conversion unit that detects a magnetic field generated by the primary conductor that forms the coil. (For example, Patent Document 1)

Japanese Patent Laying-Open No. 2005-37297 (page 12, FIG. 8)

Generally, a current detection device includes a primary conductor that forms a coil that converts a load current into a magnetic field, and a magnetoelectric conversion unit that detects a magnetic field generated by the primary conductor that forms the coil.

The magnetoelectric conversion part is formed by a coil in which a conducting wire is wound around a donut-shaped magnetic core called a toroidal core. Therefore, there was a problem that it would be expensive. On the other hand, there is also a current detection device that uses a method of detecting the magnetic field generated by the current flowing in the primary conductor by using a coil with a conductive wire wound around a rod-shaped magnetic core as the magnetoelectric conversion section, without using a toroidal core. To do. However, since the magnetoelectric conversion unit does not surround the primary conductor around the current detection device that uses a coil with a wire wound around a rod-shaped magnetic core as the magnetoelectric conversion unit, if the positions of the primary conductor and the magnetoelectric conversion unit change Since the value of the signal to be changed changes, there is a problem that the current cannot be detected accurately.

  The present invention has been made in view of the above problems, and an object thereof is to provide a highly accurate current detection device that does not require much time for manufacturing, and a watt hour meter using the current detection device.

In order to achieve the above object, a current detection device according to the present invention is disposed so as to circulate in a cross-sectional direction of a conductive portion made of a metal conductor for conducting a current to be measured, and electrically connected in series. A plurality of connected coils, and a plurality of support portions made of a magnetic material magnetically connected to the adjacent coils in series while engaging and supporting ends of adjacent coils among the plurality of coils. It is characterized by that.

In order to achieve the above object, the watt-hour meter according to the present invention includes a conductive portion made of a metal conductor and a plurality of electrically connected electric series units arranged around the cross-sectional direction of the conductive portion. And a plurality of support portions made of a magnetic material magnetically connected to the adjacent coils in series while engaging and supporting the ends of adjacent coils among the plurality of coils, and the conductive portion Current detecting means for detecting the current of the system under measurement flowing through the circuit, voltage detecting means for detecting the voltage of the system under measurement, a signal relating to the current of the system under test detected by the current detecting means, and the voltage detection And power calculation means for calculating data relating to the amount of power from the signal applied to the voltage of the system under test detected by the means.

ADVANTAGE OF THE INVENTION According to this invention, a highly accurate electric current detection apparatus which does not require an effort for manufacture, and the watt-hour meter using this can be provided.

The perspective view which shows the electric current detection apparatus concerning Example 1 by this invention. FIG. 1 is an assembly diagram showing a current detection device according to Embodiment 1 of the present invention; Sectional drawing which shows the electric current detection apparatus concerning Example 1 by this invention. The figure which shows the modification of the electric current detection apparatus concerning Example 1 by this invention. The figure which shows the modification of the electric current detection apparatus concerning Example 1 by this invention. The figure which shows the structure of the electric current detection apparatus concerning Example 2 by this invention. The figure which shows the structure of the electric current detection apparatus concerning Example 3 by this invention. The block diagram which shows the structure of the watt-hour meter concerning Example 4 by this invention.

Examples of the present invention will be described below.

[Example 1]
A first embodiment of a current detection device according to the present invention will be described with reference to FIGS. FIG. 1 is a perspective view showing a first embodiment of a current detection device according to the present invention.

  In FIG. 1, reference numeral 100 denotes a current detection device main body.

Reference numeral 110 denotes a primary conductor made of a conductive metal such as iron or copper, which conducts a load current and generates a magnetic field corresponding to the load current.

Reference numerals 120 and 130 denote coil portions, which are coils in which a conductive wire such as an enamel wire is wound around a non-conductive core material such as phenol or bake, and a low level current corresponding to the current flowing through the primary conductor 110 Outputs electrical signals such as voltage. In addition, the coil parts 120 and 130 may have a core material with a hollow structure, or may have a core material filled with the material up to the inside. A magnetic material such as ferrite or permalloy may be used as a core material. In addition, the coil portions 120 and 130 may not be provided with a core material, and may be formed by joining coil conductors with a bonding agent such as a fusion material or an adhesive to form a coil.

Reference numerals 140 and 150 denote support parts made of a magnetic material such as ferrite or permalloy, and sandwich and support the coil parts 120 and 130.

A connection line 160 electrically connects the coil part 120 and the coil part 130 in series.

Reference numerals 170 and 180 denote output terminals that output electric signals such as low-level current and voltage corresponding to the current flowing through the primary conductor 110.

FIG. 2 is an assembly diagram of the current detection device 100.

The support part 140 has a recess 201 and a recess 202 and is engaged with one end of the coil part 120 and the coil part 130. Thereafter, the primary conductor 110 is disposed between the coil portions 120 and 130. Thereafter, the other end of the coil part 120 and the coil part 130 is engaged with the concave part 203 and the concave part 204 of the support part 150.

  FIG. 3 is a cross-sectional view of the current detection device 100. By assembling as described above, the respective parts are combined as shown in FIG. The support part 140 and the support part 150 are fixed to the coil part 120 and the coil part 130 with an adhesive or the like. Moreover, the support part 140 and the support part 150, and the coil part 120 and the coil part 130 may be engaged by rubbing so that removal is possible.

Next, the operation of this embodiment will be described with reference to FIG.

Coil units 120 and 130 receive a magnetic field generated by a current flowing through primary conductor 110 and generate an electrical signal corresponding to the current in the coil conductor. One end of the coil conductors of the coil portions 120 and 130 are connected by a connection line 160 so that the coil portions 120 and 130 are electrically connected in series. The other ends of the coil conductors of the coil portions 120 and 130 are connected to the output terminals 170 and 180, and an electric signal corresponding to the current flowing through the primary conductor 110 is output to the output terminals 170 and 180. The core material of the coil portions 120 and 130 may have a hollow structure or may be filled with a material that forms the core material to the inside. Moreover, you may be comprised with magnetic bodies, such as a ferrite and a permalloy. In addition, the coil portions 120 and 130 may not be provided with a core material, and may be formed by joining coil conductors with a bonding agent such as a fusion material or an adhesive to form a coil. When a nonmagnetic material is used for the core material, or when the coil does not have a core material, the coil portions 120 and 130 are so-called air-core coupling coils.

The support portions 140 and 150 mechanically fix the coil portions 120 and 130. Since the support portions 140 and 150 are made of a magnetic material such as ferrite or permalloy and have a low magnetic resistance, the support portions 140 and 150 transmit the magnetic field generated by the current flowing through the primary conductor 110 to the coil portions 120 and 130. Since the primary conductor 110 is circulated by the coil portions 120 and 130 and the support portions 140 and 150, the coil portions 120 and 130 and the support portions 140 and 150 are determined according to Bio-Savart's law and Ampere's law of circular integration. On the other hand, even if the position of the primary conductor 110 is shifted, the current flowing through the primary conductor 110 can be detected with high accuracy.

In this embodiment, the coil portions 120 and 130 are engaged with the recesses 201 and 202 of the support portion 140 and the recesses 203 and 204 of the support portion 150. However, the support portions 140 and 150 do not include the recesses, The coil portions 120 and 130 may be fixed to the support portions 140 and 150 with an adhesive or the like.

By using this embodiment, it is possible to provide a highly accurate current detection device that does not require labor for manufacturing.

Since the coil portions 120 and 130 are manufactured by winding coil conductors such as enamel wires in a cylindrical shape, they are easier to manufacture than toroidal coils manufactured by winding a coil conductor around a donut-shaped core material. .

In addition, the coil parts 120 and 130 are the same part, and the coil part can be easily manufactured, and the core material constituting the coil part can be the same part, saving the mold required for manufacturing the core material. be able to.

In addition, the support parts 140 and 150 are the same part, and the manufacture of the support part is easy, and the mold required for the manufacture of the support part can be saved, which is economical.

Also, since the coil conductors forming the coil ends of the coil portions 120 and 130 are inserted into the recesses of the support portions 140 and 150 made of a magnetic material, a current detection device that is strong against external magnetic field noise is provided. Can do.

Moreover, you may comprise an electric current detection apparatus as shown in FIG. The coil part 120 has a hollow structure, and one end of a coil conducting wire forming the coil is electrically connected to a wire 401 that passes through the inside of the coil part 120. The coil part 130 has a hollow structure, and one end of a coil conducting wire forming the coil is electrically connected to a wire 402 passing through the inside of the coil 130. The wire 401 and the wire 402 are electrically connected by the wire 403 on the support part 140 side. Thereby, the coil part 120 and the coil part 130 are electrically connected in series.

With this configuration, the wire 403 is provided on the same support 140 side as the output terminals 170 and 180, so that the assembly of the current detection device is facilitated.

In addition, when a connection wire for electrically connecting the coil unit 120 and the coil unit 130 is provided on the support unit 150 side, a loop is formed by the coil conducting wire and the connection wire, but the wire 403 is connected to the output terminals 170 and 180. By being provided on the same support part 140 side, it is possible to provide a current detection device that is not looped and is strong against external magnetic field noise.

Further, if the current detection device is configured such that the support portion 150 can be attached to and detached from the coil portions 120 and 130, a clamp-type current detection device can be obtained. This is because the wire 403 is provided on the support 140 side, so that it does not get in the way when the current detection device is attached to the primary conductor 110.

Moreover, you may comprise an electric current detection apparatus as shown in FIG. The coil conductors of the coil portions 120 and 130 are multi-winding, and the end of the coil conductor wound around the outermost layer of the coil 120 and the end of the coil conductor wound around the outermost layer of the coil 130 are connected at a connection line 501. Electrically connected. Thereby, the coil part 120 and the coil part 130 are electrically connected in series. Further, an intermediate terminal 502 electrically connected to the connection line 501 is provided, and the intermediate terminal 502 is connected to the ground potential 511 of the post-stage circuit 510. The output terminals 170 and 180 are connected to the post-stage circuit 510 via the shield line 520, and the shield portion of the shield line 520 is connected to the ground potential 511 of the post-stage circuit 510. When the coil conductor layers of the coil portions 120 and 130 that are multiple-wrapped are even layers, the coil portion 120 and the coil portion 130 are electrically connected by the wire 501 on the support portion 140 side.

By being configured in this manner, the coil conductor wound on the outermost layer becomes the ground potential, so that it is difficult to receive an electrical disturbance.

Further, when the coil conductor layers of the coil portions 120 and 130 are made into even-numbered layers, the wire 501 is provided on the same support portion 140 side as the output terminals 170 and 180, so that the current detection device can be easily assembled. Become.

By using the present invention, it is possible to provide a highly accurate current detection device that does not require labor for manufacturing.

[Example 2]
A second embodiment of the current detection device according to the present invention will be described with reference to FIG. FIG. 6 is a diagram (sectional view) illustrating the magnetoelectric conversion unit 600 of the current detection device according to the second embodiment. In addition, about each part of this Example 2, the same part as each part of the magnetoelectric conversion part 100 in Example 1 shown in FIG. 3 is shown with the same code | symbol.
The difference between the second embodiment and the first embodiment is that, in the first embodiment, the coil portions 120 and 130 have a linear shape, whereas in the second embodiment, the coil portions 610 and 620 are semicircular. This is a point having an arc shape.

Reference numeral 110 denotes a primary conductor made of a conductive metal such as iron or copper, which conducts a load current and generates a magnetic field that is directly proportional to the load current.

Reference numerals 610 and 620 denote coils, which are coils in which a conductive wire such as an enamel wire is wound around a non-conductive core material such as phenol or bake, and outputs an electrical signal corresponding to the current flowing through the primary conductor 110. . The coil portions 610 and 620 may have a hollow core material, or may have a core material filled up to the inside. A magnetic material such as ferrite or permalloy may be used as a core material. Moreover, the coil parts 610 and 620 may not be provided with a core material, and may be formed by joining coil conductors with a bonding agent such as a fusion material or an adhesive to form a coil. Reference numerals 630 and 640 denote support parts, which are made of a magnetic material such as ferrite or permalloy, and support the coil parts 610 and 620.

Coil units 610 and 620 receive a magnetic field generated by the current flowing through primary conductor 110 and generate an electrical signal corresponding to the current in the coil conductor. One ends of the coil conductors of the coil portions 610 and 620 are connected so that the coil portions 610 and 620 are electrically connected in series. The other ends of the coil conductors of the coil portions 610 and 620 are connected to the output terminals 170 and 180, and an electric signal corresponding to the current flowing through the primary conductor 110 is output to the output terminals 170 and 180. The coil portions 610 and 620 may have a hollow structure or may be filled with a material that forms a core material. Moreover, you may be comprised with magnetic bodies, such as a ferrite and a permalloy. Moreover, the coil parts 610 and 620 may not be provided with a core material, and may be formed by joining coil conductors with a bonding agent such as a fusion material or an adhesive to form a coil.

Support parts 630 and 640 mechanically fix coil parts 610 and 620. Further, since the support parts 630 and 640 are made of a magnetic material such as ferrite or permalloy and have a low magnetic resistance, the magnetic fields generated by the current flowing through the primary conductor 110 are transmitted to the coil parts 610 and 620. Since the primary conductor 110 is circulated by the coil portions 610 and 620 and the support portions 630 and 640, the coil portions 610 and 620 and the support portions 630 and 640 are in accordance with Bio-Savart's law and Ampere's law of revolving integration. On the other hand, even if the position of the primary conductor 110 is shifted, the current flowing through the primary conductor 110 can be detected with high accuracy.

In the present embodiment, the two coil portions of the coil portions 610 and 620 and the two support portions of the support portions 630 and 640 are provided. One support portion made of a magnetic material that engages and supports both ends of the coil portion and is magnetically conductive is provided so as to circulate with the coil portion in the cross-sectional direction of the conductive portion 110. Also good.

By using this embodiment, it is possible to provide a highly accurate current detection device that does not require labor for manufacturing.

Since the coil portions 610 and 620 are manufactured by winding a coil conductor such as an enamel wire in a semicircular shape, it is easier to manufacture than a toroidal coil manufactured by winding a coil wire around a doughnut-shaped core. is there.

In addition, the coil parts 610 and 620 are the same part, and the coil part can be easily manufactured, and the core material constituting the coil part can be the same part, saving the mold required for manufacturing the core material. be able to.

Further, the support portions 630 and 640 are the same part, and the manufacture of the support portion is easy, and the molds and the like required for manufacturing the support portion can be saved, which is economical.

By using the present invention, it is possible to provide a highly accurate current detection device that does not require labor for manufacturing.

[Example 3]
A third embodiment of the current detection device according to the present invention will be described with reference to FIG. FIG. 7 is a diagram (sectional view) illustrating the magnetoelectric conversion unit 700 of the current detection device according to the third embodiment. In addition, about each part of this Example 3, the same part as each part of the magnetoelectric conversion part 100 in Example 1 shown in FIG. 3 is shown with the same code | symbol.
The third embodiment is different from the first embodiment in that the first embodiment includes two coil portions 120 and 130, whereas the third embodiment has coil portions 710, 720, and 730. , 740, four coil portions.

Reference numeral 110 denotes a primary conductor made of a conductive metal such as iron or copper, which conducts a load current and generates a magnetic field corresponding to the load current.

Reference numerals 710, 720, 730, and 740 denote coils, which are coils in which a conductive wire such as an enamel wire is wound around a non-conductive core material such as phenol or bake, and corresponds to the current flowing through the primary conductor 110. Output a signal. The coil portions 710, 720, 730, and 740 may have a hollow core material, or may have a core material filled up to the inside. A magnetic material such as ferrite or permalloy may be used as a core material. In addition, the coil portions 710, 720, 730, and 740 may not be provided with a core material, and may be formed by joining coil conductors with a bonding agent such as a fusion material or an adhesive.

Reference numerals 750, 760, 770, and 780 are support parts made of a magnetic material such as ferrite or permalloy, the support parts 780 and 750 are the coil part 710, the support parts 750 and 760 are the coil part 720, and the support part 760. And 770 support the coil portion 730, and the support portions 770 and 780 support the coil portion 740.

Coil portions 710, 720, 730, and 740 receive a magnetic field generated by a current flowing through primary conductor 110, and generate an electrical signal corresponding to the current in the coil conductor. Coil portions 710, 720, 730, and 740 are connected so as to be electrically connected in series. In addition, the ends of the coil conductors of the coil units 710, 720, 730, and 740 that are electrically connected in series are connected to the output terminals 170 and 180, and the output terminals 170 and 180 have a current flowing through the primary conductor 110. A corresponding electrical signal is output. The core material of the coil portions 710, 720, 730, and 740 may have a hollow structure or may be filled with a material that forms the core material up to the inside. Moreover, you may be comprised with magnetic bodies, such as a ferrite and a permalloy. In addition, the coil portions 710, 720, 730, and 740 may not be provided with a core material, and may be formed by joining coil conductors with a bonding agent such as a fusion material or an adhesive.

The support portions 750, 760, 770, and 780 mechanically fix the coil portions 710, 720, 730, and 740. Further, since the support portions 750, 760, 770, 780 are made of a magnetic material such as ferrite or permalloy and have a low magnetic resistance, a magnetic field generated by a current flowing through the primary conductor 110 is applied to each coil portion 710, 720, 730 and 740. Since the primary conductor 110 is circulated by the coil portions 710, 720, 730, 740 and the support portions 750, 760, 770, 780, each coil portion is in accordance with Bio-Savart's law and Ampere's revolving integral law. On the other hand, even if the position of the primary conductor 110 is shifted, the current flowing through the primary conductor 110 can be detected with high accuracy.

By using this embodiment, it is possible to provide a highly accurate current detection device that does not require labor for manufacturing.

Since the coil portions 710, 720, 730, and 740 are manufactured by winding coil conductors such as enamel wires in a columnar shape, the toroidal type coil is manufactured by winding coil conductors around a donut-shaped core material. Easy to manufacture.

In addition, the coil parts 710, 720, 730, and 740 are the same part, and the coil part can be easily manufactured, and the core material constituting the coil part can be the same part. Etc. can also be saved.

Further, the support portions 750, 760, 770, and 780 are the same parts and are easy to manufacture, and it is economical because a mold required for manufacturing the support portions can be saved.

Further, if the current detection device is configured so that the support portion 760 can be attached to and detached from the coil portions 720 and 730, a clamp-type current detection device can be obtained.

By using the present invention, it is possible to provide a highly accurate current detection device that does not require labor for manufacturing.

[Example 4]
An embodiment of a watt hour meter using the current detection device according to the present invention will be described with reference to FIG. FIG. 8 is a block diagram showing a configuration example of the watt-hour meter.

Reference numeral 801 denotes a current detection unit, which corresponds to the current detection device 100 shown in the first embodiment, the current detection device 600 shown in the second embodiment, and the current detection device 700 shown in the third embodiment. The current detection unit 801 detects a use current (A1) used at a consumer's load, converts it into a low-level electrical signal corresponding to the use current, and outputs it.

Reference numeral 802 denotes a voltage detector, which is composed of a voltage transformer, a voltage dividing resistor such as an attenuator, and the like, detects a use voltage (V1) used in a consumer load, and is at a low level in direct proportion to the use voltage. Converted into an electrical signal and output.

Reference numeral 803 denotes a power calculation unit, which includes a digital multiplication circuit, a DSP (digital signal processor), and the like. A signal related to the current (A1) output from the current detection unit 701 and a voltage detection unit 802 output the signal. The signal related to the used voltage (V1) is multiplied and converted into data (A1 · V1) that is directly proportional to the power used by the consumer. Furthermore, the power calculation unit 803 edits and outputs the calculation result of data (A1 · V1) that is directly proportional to the power consumption as usage data. Here, the usage data refers to data related to the power used by the customer, such as the total accumulated power used by the customer's load and the time zone usage for each time zone. Further, since the signal related to the used current (A1) output from the current detector 801 is a signal that is directly proportional to a signal obtained by differentiating the used current (A1), data (A1 · V1) that is directly proportional to the consumed power of the consumer. ) Is integrated by the power calculation unit 803.

A display unit 804 includes a liquid crystal display and the like, and displays usage data.

By using this embodiment, it is possible to provide a watt-hour meter having a highly accurate current detection device that does not require labor for manufacturing.

100 Current detection device main body 110 Primary conductor 120, 130 Coil portion 140, 150 Support portion 160 Connection portion 170, 180 Output terminal 201, 202, 203, 204 Recess 401, 402 Wire rod 403 Wire rod 501 Connection wire 502 Intermediate terminal 510 Subsequent circuit 511 Ground potential 520 Shield wire 610, 620 Coil portion 630, 640 Support portion 631, 632, 641, 642 Recess 710, 720, 730, 740 Coil portion 750, 760, 770, 780 Support portion 751, 752 Recess 761, 762 Recess 771 , 772 Concave part 781, 782 Concave part 801 Current detection part 802 Voltage detection part 803 Power calculation part 804 Display part

Claims (13)

A conductive portion made of a metal conductor for conducting the current to be measured;
A plurality of coils arranged so as to circulate with respect to the cross-sectional direction of the conductive portion and electrically connected in series;
An electric current detection comprising: engaging and supporting ends of adjacent coils of the plurality of coils; and a plurality of support portions made of a magnetic body magnetically connected to the adjacent coils in series. apparatus. The current detection device according to claim 1, wherein the plurality of coils have the same shape. The current detection device according to claim 1, wherein the plurality of support portions have the same shape. 4. The current detection device according to claim 1, wherein coil supporting wires forming coil ends of the plurality of coils are covered with the support portion. 5. The current detection device according to claim 1, wherein the plurality of coils include a core material made of a nonmagnetic material. 5. The current detection device according to claim 1, wherein the plurality of coils are formed by bonding coil conductors with a bonding agent. 6. The current detection device according to claim 1, wherein the plurality of coils have a cylindrical shape whose height direction is substantially linear. The current detection device according to claim 1, wherein the plurality of coils have a cylindrical shape whose height direction is an arc shape. 9. The current detection device according to claim 1, wherein at least one of the plurality of support portions is detachable from a coil that is supported and engaged among the plurality of coils. 10. The plurality of coils have coil conductors wound on a plurality of layers,
10. The external circuit connection terminal according to claim 1, further comprising an external circuit connection terminal to which a coil wire wound on an outermost layer of at least one of the plurality of coils is electrically connected. The current detection device described. 11. The current detection device according to claim 1, wherein the plurality of coils are electrically connected in series with a connection line that does not circulate with respect to a cross section of the conductive portion. A conductive portion made of a metal conductor for conducting the current to be measured;
A coil disposed in proximity to the conductive portion;
A current detection device comprising: a support portion made of a magnetic body that engages and supports both ends of the coil and is arranged so as to circulate with the coil in a cross-sectional direction of the conductive portion. A conductive portion made of a metal conductor;
A plurality of coils arranged so as to circulate with respect to the cross-sectional direction of the conductive portion and electrically connected in series;
The device under test is configured to engage and support the ends of adjacent coils among the plurality of coils and to have a plurality of support portions made of a magnetic material magnetically connected to the adjacent coils in series, and to flow through the conductive portion. Current detection means for detecting the current of the system;
Voltage detection means for detecting the voltage of the system under measurement;
A power calculation means for calculating data relating to an electric energy from a signal relating to the current of the measured system detected by the current detection means and a signal relating to the voltage of the measured system detected by the voltage detection means; A watt hour meter characterized by comprising:

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