JP2009010637A - Coupler for power line communication system, assembly structure of combiner, and power line communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coupler for a power line communication system capable of being assembled even in a narrow space made with loosened strands, without enlargement in the coupler and deterioration in its assembly workability. <P>SOLUTION: The coupler for the power line communication system comprises a plurality of annular members 2 attached in a condition that a power line is penetrated into its center hole in order to output and input a high frequency signal to the power line. The annular member has a configuration where two ends 10a of a half-annular strip 10 made of magnetic material are contacted and jointed through a first insulating spacer 21, and a plurality of the annular members are laminated through a second insulating spacer 22 and bundled/bound by a bundle/bind member 30. The bundle/bind member 30 bundles/binds each annular member individually in a radial direction move enable fashion. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an improvement of a coupler for a power line communication system used for coupling a power line carrier communication apparatus and a power line in a power line communication system, and more particularly to individual power lines constituting a stranded wire composed of a plurality of cables. The present invention relates to a small coupler that can greatly improve the workability of mounting.

When constructing a communication system using a power line drawn into a customer's building, a high-frequency signal (2 MHz to 30 MHz frequency band) from the network line is superimposed on the power line, or a high-frequency signal is extracted from the power line. Means are needed.
For example, a power line drawn from a utility pole into a building is wired and connected to each room and each load by a trunk cable branched by a distribution board. On the other hand, when a signal of a network line (for example, an optical line) drawn into the building from the outside is coupled to a power line, the optical line is connected to a power line carrier communication device via an optical modem, and further the power line A signal line extending from the carrier communication device is superimposed on and extracted from the power line using a coupler. In power line communication, a coupler for superimposing / extracting a high frequency signal on a power line is the most important component that affects the performance of the system.
As one of such superposition / extraction means, a means using a ferrite core 151 as shown in FIG. 7 is known. In this method, the power line 150 and the signal line 152 are held by the ferrite core 151 coupled to each of the two power lines 150, and a high frequency signal transmitted from the power line carrier communication device (PLC modem) 153 via the signal line 152 is received. The power line 150 is superposed by magnetic coupling. Also, when the power line carrier communication device 153 receives a high frequency signal, the high frequency signal superimposed on the power line 150 appears on the surface of the power line 150 due to the skin effect, so if the signal line 152 is sandwiched between the surfaces of the power line 150, Only a high-frequency signal can be extracted by the magnetic coupling force.

As a means for superimposing / extracting signals in an electromagnetic induction coupling (magnetic coupling) circuit using a ferrite core, there is a clamp type coupler shown in FIG.
The clamping method shown in FIG. 8 is one of superposition / extraction methods in which an annular ferrite 160 is inserted into the power line 165, and the merit that the construction can be carried out without directly contacting the conductor portion of the power line 165 carrying a current of about 30A. There is. However, since the ferrite 160 and the power line 165 are electromagnetically coupled, when the value of the current flowing through the power line 165 is too high, the signal is difficult to be superimposed because of saturation. For this reason, the annular ferrite 160 is composed of two ferrite divided pieces 160a that are divided into a semi-annular shape, and a saturation current value is controlled by providing a gap by sandwiching an insulator between the ends of both divided pieces. . However, if the value of the gap between the ends of the split pieces increases, saturation current value can be increased to prevent saturation, while the amount of coupling of high-frequency signals decreases as the gap increases. .
Conventional couplers used for high-voltage trunk cables, as disclosed in Patent Document 1, are expensive in order to satisfy the two characteristics that are in conflict with each other in dealing with large currents and ensuring the amount of coupling. This has been achieved by using simple materials, large shapes, and complicated structures. However, it cannot meet the demands for lower prices, smaller size, and simplified structure.

Next, in an office building in Japan, a triplex type cable 170 as shown in FIG. 9A is often used as a trunk cable connecting an electrical room and a distribution board. The cable 170 has a stranded wire structure in which three single wires 171 are integrated, and a current of about 60 to 100 A is passed through each single wire. When a high frequency signal is superimposed on the single wire 171, a space for assembling a commercially available cylindrical ferrite 175 (for 200 to 300A) by loosening part of the stranded wire into three single wires as shown in FIG. 9B. It is necessary to ensure. However, since the ferrite 175 for a large current has to be a long and large-diameter cylindrical body, it is not easy to assemble the individual single wire 171 and the workability is extremely poor.
Patent Document 2 discloses a coupler that applies a ferrite core for EMI countermeasures for a power line through which a low current of about 20 A is passed. Because this coupler is small, it can be installed in an assembly space with loose strands, but when applied to a normal power line, it is easily saturated by the current of the commercial power source and used as a coupler. There was a problem that I could not.
Japanese Patent No. 3327927 JP 2006-5888 A

As described above, the coupler used in the conventional power line communication system is made of an annular (axial dimension is shorter than radial dimension) or cylindrical (axial dimension is longer than radial dimension) ferrite. Various problems occurred because one book was assembled at a time. First, when using a ferrite core in which semi-annular divided pieces are assembled in an annular shape, the saturation current value can be increased and saturation can be prevented if the gap value between the ends of the divided pieces increases. However, when the value becomes large, there is a problem that the amount of coupling of high-frequency signals decreases, and adjustment is difficult. Moreover, the cylindrical ferrite used for the coupler for large currents has a problem that it is very difficult to assemble the single wire using the space where the stranded wire is loosened.
The present invention has been made in view of the above-described conventional circumstances, and is a coupler for a power line communication system that can be assembled even in a narrow space where a stranded wire is loosened without causing an increase in size or a reduction in assembly workability. The purpose is to provide.

To achieve the above object, a coupler for a power line communication system according to the invention of claim 1 is provided with a plurality of annular members attached in a state where the power line is inserted into the center hole in order to input / output a high frequency signal to / from the power line. A coupler for a power line communication system, wherein the annular member has a configuration in which two end portions of a semi-annular piece made of a magnetic material are in contact with each other via a first insulating spacer, In a state where the annular members are stacked via the second insulating spacer, a binding member for binding the plurality of annular members is provided, and the binding members can individually move the respective annular members in the radial direction. It is characterized by binding.
According to the present invention, it is possible to eliminate the disadvantage that the coupling amount is small due to the axial cross-sectional area of the magnetic body constituting each annular member being too small, and to improve the assembly workability. That is, the individual annular members are not easily saturated because the gap is formed by the first insulating spacer between the ends of the two semi-annular pieces, but the presence of the gap causes the signal between the signal line and the power line. The amount of movement is reduced. Therefore, in the present invention, a plurality of annular members are stacked in a non-contact state to increase the total cross-sectional area of the coupler as a whole, making it difficult to saturate, and increasing the total signal amount (injection amount, coupling amount). When an annular magnetic body is directly connected to increase the axial cross-sectional area, saturation tends to occur. However, it can be made difficult to saturate by stacking via an insulating spacer.

According to a second aspect of the present invention, in the first aspect, the two semi-annular pieces constituting the annular member are annularly closed by a band member that is crimped to the outer peripheral surface thereof, and one of the semi-annular pieces is It is configured to be openable and closable between an open posture in which the other end is opened with the end serving as a fulcrum.
The invention of claim 3 is characterized in that, in claim 1 or 2, a bundled band is used as the binding member.
The assembly structure of the coupler according to the invention of claim 4 is characterized in that the power line and the signal line extending from the power line carrier communication device are connected to the central hole of the coupler for a power line communication system according to any one of claims 1 to 3. The binding member is assembled to the power line while being inserted into the power line.
A power line communication system according to a fifth aspect of the present invention is the coupler, the power line carrier communication apparatus, and the network according to the first to third aspects, wherein the coupler is assembled to the power line and the signal line by the assembly structure according to the fourth aspect. And a line.

In Japan, when a signal line extending from a power line carrier communication device is electromagnetically coupled to a power line having three single wires as a stranded wire using a coupler, in order to reduce leakage and increase superposition efficiency, It is required to assemble a coupler for each single wire.
In the present invention, not only a coupler composed of a plurality of annular members is used, but also the gap (first gap) between the semi-annular pieces constituting each annular member is increased in order to increase the saturation current value. Yes. When the first gap is increased, the total coupling capacity is reduced. Therefore, as a countermeasure, a plurality of annular members are stacked via the second insulating spacer to secure an axial cross-sectional area, and for a commercially available low current. A coupling capacity equivalent to that of the coupler is ensured.

Further, since each annular member is semi-fixed by the binding member, each annular member can move in the radial direction by about several millimeters.
The triplex-type stranded cable to be assembled with the coupler has a three-dimensionally bent structure, but the coupler according to the present invention moves in the radial direction because the individual annular members move in the radial direction. Thus, the coupler can be installed, and the installation workability can be improved.
Although it is a structure in which a plurality of annular members are laminated, since it is a structure that opens and closes integrally, it can be assembled to the power line by a single operation without cutting the power line or causing a power failure.

Hereinafter, the coupler for power line communication systems which concerns on this invention is demonstrated in detail based on drawing.
1 (a) and 1 (b) are a perspective view and a bottom view showing a closed configuration of a coupler for a power line communication system (hereinafter referred to as a coupler) according to an embodiment of the present invention. ) Is a perspective view showing an open state. Further, FIG. 2 is a diagram showing the configuration of the coupler from which the band member has been removed.
The coupler 1 is characterized by a configuration in which a plurality of annular members 2 that pass through the power line through the central hole 3 in order to input and output a high-frequency signal to the power line are stacked (overlapped).
The annular member 2 has a configuration in which two end portions 10 a of a semi-annular piece 10 made of a magnetic material having high magnetic permeability, for example, ferrite are brought into contact with each other via a first insulating spacer 21.
The ferrite constituting each semi-annular piece 10 is used for the purpose of magnetically coupling high-frequency signals. The first insulating spacer 21 is used for the purpose of forming a first gap G1 between the end portions 10a of the semi-annular pieces 10 so as not to contact them.
The number of annular members 2 to be used may be set as appropriate according to the degree of saturation due to the current flowing through the power line and the coupling of the high frequency signal, and is not limited to three.
As will be described later, since the two semi-annular pieces 10 are configured so that the other end 10a can be opened and closed with the one end 10a as the center, the first insulating spacer 21 has an inner portion of the two ends 10a facing each other. It adheres to only one of these, and it is set as the structure which does not adhere between the other edge parts.

The greater the gap between the first gaps G1, the less likely it is to saturate due to the influence of the current flowing through the power line, while the greater the gap between the first gaps G1, the lower the amount of electromagnetic coupling between the power line and the signal line. The signal superimposition / extraction characteristics deteriorate. In the present invention, a plurality of semi-annular pieces 10 having a small axial length (width) are stacked (closely arranged) via the second insulating spacer 22 so that the axial section of the entire ferrite constituting the coupler is cut. By increasing the area (the area facing the power line), it is possible to improve saturation and extraction characteristics of the signal and make it difficult to saturate.
Further, the coupler 1 includes a binding member 30 that binds the plurality of annular members 2 in a state in which the plurality of annular members 2 are stacked via the second insulating spacer 22. The binding member 30 is means for binding (semi-fixing) each annular member 2 individually so as to be movable in the radial direction. In this example, the binding member 30 is attached at two locations avoiding the end portion 10a of the annular member. While the plurality of annular members 2 are connected in the axial direction by the binding member 30, the individual annular members can be individually moved in the radial direction, so that the power line is inserted into the center hole as will be described later. Even in the state, the radial position of each annular member can be shifted according to the curved state of the power line.

Since the second insulating spacer 22 is disposed between the two annular members 2 that move relative to each other in an adjacent positional relationship, the second insulating spacer 22 is bonded and fixed to one of the annular members.
The second insulating spacer 22 disposed on the opposing surface of the annular member 2 to be laminated is used for the purpose of preventing the ferrites from contacting each other while keeping the distance between the annular members 2 appropriate.
Further, the two semi-annular pieces 10 constituting the annular member 2 are closed in an annularly closed state (FIGS. 1A and 1B) by a band member 40 that is crimped to the outer peripheral surface, and one end is a fulcrum. As shown in FIG. 1 (c), which can be opened and closed. The band member 40 is formed in a substantially C shape so that a flexible thin plate-like and strip-shaped resin material can be closely adhered along the outer peripheral surface of the annular member 2, and the band member 40 has an annular shape at the open end 40 a. It is assembled so that one end 10a of the member is positioned. Therefore, when an external force is not applied, the annular member 2 is maintained in the closed posture by the elastic force. On the other hand, when a force in the opening direction is applied, the other end is opened as a fulcrum. It is possible to shift to the released posture. Therefore, the annular member 2 can be fitted to the outer periphery of the power line with the ring member 2 opened.

FIG. 1A shows a state in which the open end 40a of the band member 40 is opened. However, when the band member 40 is closed, the annular member 2 is not opened by fastening the holes provided in the open end 40a with a connector (not shown). To fix.
As the binding member 30, for example, a commercially available bundled band as shown in FIGS. 1 and 4 can be used.
FIG. 3 (a) is a view showing a state in which the coupler of the present invention is properly attached to the power line (fixed band is omitted), and FIGS. It is a figure which shows the state attached appropriately.

When the coupler 1 of the present invention is attached to each single wire 171 in a state where a single strand 171 consisting of three single wires as shown in FIG. 10 is loosened, the coupler of the present invention is small. In addition, since it is configured to be openable and closable, it can be easily attached to each single wire 171 by utilizing a small space formed between the single wires when the stranded wires are loosened.
Even when the single wire 171 is curved or otherwise deformed in a non-linear manner as shown in the figure, each annular member 2 is held in a semi-fixed state by the binding member 30 and is displaced in the radial direction. Therefore, it can be easily assembled while following the shape of the single wire. Therefore, it can be assembled in a narrow space between the loosened single wires with good storage.
Reference numeral 152 denotes a signal line extending from a power line carrier communication device (not shown), and is inserted into the central hole 3 of the coupler 1 together with the power line 171.

On the other hand, FIG. 3B shows a state in which the distance between the annular members is separated when the plurality of annular members 2 are assembled to the power line without using the binding member 30. Thus, when the distance between the annular members is increased, the total coupling capacity of the entire coupler is reduced. This is because the coupling capacity is attenuated as the looped portion of the signal line 152 extending from the power line carrier communication apparatus shown in FIG. 7 becomes longer. Therefore, the coupling capacity obtained from the three annular members spaced apart is smaller than expected.
On the other hand, according to the present invention, the annular members are made as close as possible through the second insulating spacer 22, so that the coupling capacity obtained from each annular member is equal to the coupling capacity corresponding to the number of the annular members. Can be obtained.

Moreover, FIG.3 (c) has shown the state which the ferrite which comprises an annular member contacted. When the ferrites come into contact with each other, the saturation current value becomes small and saturation is likely to occur.
On the other hand, in the present invention, the second gap G2 is provided between the annular members by the second insulating spacer 22 having a thickness of about 1 mm, and the distance between the annular members is semi-fixed by the binding member 30. It was possible to realize an insulating structure that kept as close as possible to each other and did not make contact.
In FIG. 3A, there is no limitation on the means for fixing the coupler 1 to the power line. For example, the binding band 30 as shown in FIG. 4A or 4B is used as the binding member 30, for example. In such a case, the end 30a protruding when the bundled band is tightened can be used to assemble the power line 71. Specifically, the end portions 30a extending in the same direction from the two bundled bands assembled to each coupler 1 are assembled to the power line by another bundled band.

FIG. 5 shows a low-current coupler (low-current product, for example, a coupler disclosed in Japanese Patent Laid-Open No. 2006-5888), a gap between end portions of a semi-annular piece, that is, a coupler in which the first gap G1 is increased. (Gap processed product) and the coupling amount when the coupler of the present invention (three-stage stack) is applied, respectively.
As is clear from this figure, according to the coupler of the present invention, the same amount of coupling (transmission characteristics) as when the low current coupler was applied could be obtained.

Next, FIGS. 6A and 6B show a case where a low-current coupler (a coupler disclosed in Japanese Patent Application Laid-Open No. 2006-5888) is applied to a power line through which a current from a commercial power source is passed. It is a figure which shows each saturated state at the time of applying this coupler.
In the case of the low current (20A) coupler shown in FIG. 6 (a), the transmission characteristics at 60A energization are greatly reduced due to the deterioration of the saturation state, compared with 0A (ideal state where the power line is not energized). It is falling. For this reason, practicality is low.
On the other hand, in the case of the coupler of the present invention shown in FIG. 6 (b), the saturation state is improved as compared with the case of 0A in which the power line is not energized. There is little deterioration in characteristics, and it can be sufficiently put to practical use.

As described above, the present invention forms a single annular member by combining a semi-annular piece made of a magnetic material such as ferrite in a coupler that superimposes a high frequency signal on a power line or extracts a high frequency signal from a power line, and The power line and the signal line were inserted into the center hole in a state where a plurality of the annular members were laminated in the axial direction and brought close to each other. And since the sufficient gap is ensured by interposing the 1st insulating spacer between the edge parts of two semi-annular pieces, the current saturation by the commercial power supply which supplies with electricity to a power line can be prevented. That is, since the first gap G1 in each annular member is ensured large and each semi-annular piece has an insulating structure that does not directly contact each other, even if the current value of the commercial power supply 60A-100A is not saturated. can do.
In addition, since the annular members are laminated close to each other via the second insulating spacer having the minimum necessary thickness, the total cross-sectional area in the axial direction of the magnetic material constituting the coupler is more than a predetermined value. As a result, current saturation due to commercial current can be prevented and the coupling capacity can be increased.

Further, by semi-fixing the annular members so as to be movable in the radial direction by the binding members, the radial positions of the annular members can be appropriately assembled following the change in the shape of the power line. Furthermore, since the plurality of annular members are integrated by the binding member, the attachment work to the power line becomes easy. In particular, when a coupler is attached to two single wires in a triplex type cable with three single wires as stranded wires, the fixed clamps are structured to move horizontally, so that they are loosened. It becomes possible to install according to the shape with respect to each single wire in the.
As described above, according to the present invention, it is possible to provide a coupler that is smaller, lighter and less expensive than a commercially available coupler for large current.

(A) And (b) is a perspective view which shows the structure of the closed state of the coupler for power line communication systems which concerns on one Embodiment of this invention, and a bottom view, (c) is a perspective view which shows an open state. It is a figure which shows the structure of the coupler which removed the band member. (A) is the figure which shows the state which attached the coupler of this invention appropriately with respect to the power line (a fixed band is abbreviate | omitted), (b) (c) attached the some annular member improperly with respect to the power line. It is a figure which shows a state. (A) And (b) is a figure which shows the specific structural example of a binding member. It is the figure which showed the coupling amount at the time of applying the coupler for low current, the coupler which enlarged the 1st gap, and the coupler of this invention, respectively. (A) And (b) is a figure which shows each saturated state at the time of applying the coupler for low currents to the power line which supplies the electric current from a commercial power source, and the coupler of this invention. It is explanatory drawing of the superimposition / extraction means using a ferrite core. It is a figure which shows the example of an assembly structure in the conventional coupler. (A) And (b) is explanatory drawing of the state which assembled | attached the coupler to the structure of a strand wire, and the two single wires which comprise a strand wire.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Coupler, 2 ... Ring member, 3 ... Center hole, 10 ... Semi-annular piece, 10a ... End part, 21 ... Insulating spacer, 22 ... Insulating spacer, 30 ... Binding member (bundling band), 30a ... End 40, a band member.

Claims (5)

A power line communication system coupler comprising a plurality of annular members attached in a state where the power line is inserted through a center hole in order to input and output a high frequency signal to the power line,
The annular member has a configuration in which two end portions of a semi-annular piece made of a magnetic material are brought into contact with each other via a first insulating spacer,
In a state where the plurality of annular members are stacked via the second insulating spacer, a binding member that binds the plurality of annular members is provided,
The said binding member binds each said annular member individually so that radial movement is possible, The coupler for power line communication systems characterized by the above-mentioned.   The two semi-annular pieces constituting the annular member are closed by a band member that is crimped to the outer peripheral surface thereof, and the other end is opened with one end of each semi-annular piece as a fulcrum. The power line communication system coupler according to claim 1, wherein the coupler is configured to be openable and closable between the open postures.   The coupler for a power line communication system according to claim 1 or 2, wherein a binding band is used as the binding member.   A power line and a signal line extending from the power line carrier communication device are inserted into the center hole of the power line communication system coupler according to any one of claims 1 to 3, and the binding member is connected to the power line. The assembly structure of the coupler, which is characterized by being assembled.   5. A power line comprising: the coupler according to claim 1 assembled to a power line and a signal line by the assembly structure according to claim 4, a power line carrier communication device, and a network line. Communications system.

Images