JP3801166B2 - Power line carrier communication system - Google Patents

Description

  The present invention relates to a power line carrier communication system that performs communication using a power line, a power line carrier communication coupler to be used in this system, and a power line carrier communication system using this coupler. In particular, the present invention relates to a power line carrier communication system capable of performing communication using a high frequency signal even when a power line serving as a signal transmission path is cut off by a switch or the like.

  In recent years, communication using a power line, for example, power line communication (PLC: Power Line Communication) that performs high-speed communication by superimposing a high-frequency signal on an indoor wiring or the like has been studied (for example, see Non-Patent Document 1). In addition, power line carrier communication using not only low-voltage distribution lines (for example, about AC 100 to 200 V) such as indoor wiring but also high-voltage distribution lines (for example, about AC 6 kV to 33 kV) has been studied (see Patent Document 1). .

  FIG. 10 is an explanatory view schematically showing an outline of a power line carrier communication system using a low voltage distribution line and a high voltage distribution line. In the example shown in FIG. 10, the power supply to the houses 210A and 210B is as follows: the high-voltage (110 kV in FIG. 10) power line 220 connected to the substation → the transformer 231 in the first transformer room 230 → the high-voltage distribution line 90 20kV) → transformer 241 in second transformer room 240 → low voltage distribution line 100 (220V) → electric energy meter room 250 → indoor wiring 211A and 211B of each house 210A and 210B.

  Each house 210A and 210B includes a PLC modem (child modem) 260 for performing power line carrier communication. In addition, in the power line serving as a signal transmission line, the low-voltage distribution line 100 includes a relay modem 261 that relays high-frequency signals, a PLC modem (first parent modem) 262 connected to the low-voltage distribution line 100 and the high-voltage distribution line 90, A PLC modem (second parent modem) 263 connected to the high voltage distribution line 90 and the backbone network NT is provided. Note that the example shown in FIG. 10 shows an example in which an optical fiber network is used as the backbone network.

  In this system, for example, when a PLC user receives a high-frequency signal from the backbone network NT, the high-frequency signal transmitted from the backbone network NT is transmitted from the optical fiber cable 400 to the media converter (not shown) via the connection box 401. Is converted into an optical signal / electrical signal, sent to the second parent modem 263, modulated / demodulated, and injected into the high voltage distribution line 90. Then, this high frequency signal is modulated / demodulated by the first parent modem 262 and injected into the low voltage distribution line 100, and the frequency is appropriately converted by the relay modem 261 on the way, indoor wiring 211A of each house 210A, 210B, After passing through 211B, the data is extracted by the terminal device 270 such as a personal computer via the child modem 260.

  High-voltage distribution lines are generally laid in a wide range and used as power supply trunks. Therefore, the backbone network is not expanded, and even if the connection point with the backbone network (connection box 401 in FIG. 10) is away from the PLC user's house, the high-voltage distribution line should be used in addition to the low-voltage distribution line. Thus, communication with the outside becomes possible.

  In addition, since the high-voltage distribution line is a trunk line for power supply, the two lines are connected to the house so that power can be supplied to the house even when an accident or maintenance work is performed. There are some which are properly used as a power supply line for normal time and a power supply line for other than normal time. The normal power supply line is a service line, and the non-normal power supply line is a backup line.

  For example, in the example shown in FIG. 11, the high-voltage distribution line 90 includes a first distribution line 91 and a second distribution line 92, and the houses 200A and 200B use the first distribution line 91 as a service line and the second distribution line. The electric wire 92 is used as a backup line. Some houses have a service line and a backup line opposite to the houses 200A and 200B. For example, in the houses 200C and 200D, the second distribution line 92 is a service line, and the first distribution line 91 is a backup line. The first distribution line 91 and the second distribution line 92 are usually three-phase three-wire cables.

Switching between the service line and the backup line is performed by a switch unit provided in the first distribution line 91 and the second distribution line 92. For example, in a house 200A, 'switching section S ₁ is provided, the wiring 92A for connecting the second distribution line 92 and the house 200A' wire 91A for connecting the first distribution line 91 and the house 200A switch portion S ₂ Is provided. In normal times, the switch part S ₁ is turned on and the switch part S ₂ is turned off, and is converted into an appropriate voltage from the first distribution line 91 through the wiring 91A ′ by the transformer 95A. Then, power is supplied to the house 200A. On the other hand, the first distribution line 91 and the wiring 91A ', except normal of accidents or maintenance work of the transformer 95A, the switch section S ₁ is turned off, the switch section S ₂ is turned on, the first distribution line 91 and the wiring 91A The electric power supply by 'is cut off, and electric power is supplied to the house 200A through the second distribution line 92 and the wiring 92A'. The service line and the backup line similarly similarly house 200B and house 200A, normal time, 'on the switch portion S ₅ provided on the wiring 92B' wiring 91B switching section S ₆ is turned off provided, usually except when the switch section S ₅ is turned off, the switch section S ₆ is turned on. On the other hand, the house 200C service line and the backup line is different, the normal, 'switch section S ₃ provided in the off line 92C' wiring 91C switch section S ₄ provided is turned on, the second distribution line 92 and 'power supply is performed by, when normal except during the switch section S ₃ is turned on, the switch section S ₄ is turned off, the first distribution line 91 and the wiring 91C' wiring 92C power supply is performed by. Like the house 200D also houses 200C, normal is 'switch portion S ₈ is turned on provided in the wiring 91D' wiring 92D When the switch section S ₇ provided in the off, other than normal, the switch unit S ₈ is turned off, the switch unit S ₇ is turned on.

JP 2002-217796 A Kiyoshi Eto, “Current Status of Power Line Communication (PLC)”, Interface, CQ Publisher, September 2000, p.70-81

  In the power line as described above, when performing power line carrier communication using a high-voltage distribution line as a signal transmission line, there is a problem that communication cannot be performed between houses with different service lines and backup lines.

For example, let us consider a case where PLC modems (parent modems) 501A to 501D are arranged on wirings 91A ′ to 91D ′ as shown in FIG. 11, and only PLC modem 501A is connected to backbone network NT. Normal switch portion S ₁ is on, houses 200A is a wiring 91A 'and the signal transmission line, may communicate with the backbone network NT via the PLC modem 501A. Further, the PLC modem 501A can extract a high-frequency signal transmitted to the first distribution line 91 and inject a high-frequency signal into the first distribution line 91. Therefore, in the houses 200B to the first distribution line 91 and service lines, normal switching section S ₅ is on, the PLC modem 501B, extraction / first distribution line of the high-frequency signal transmitted to the first distribution line 91 The high frequency signal can be injected into 91. Accordingly, the house 200B can communicate with the backbone network NT using the PLC modem 501A.

However, in the houses 200C and 200D that use the second distribution line 92 as a service line, the switch units S ₃ and S ₇ provided on the first distribution line 91 (wiring 91C 'and 91D') are normally turned off. Yes. Therefore, the PLC modems 501C and 501D cannot extract the high frequency signal transmitted to the first distribution line 91 / inject the high frequency signal into the first distribution line 91, and cannot communicate with the backbone network NT.

  Further, the house 200A and the house 200B can communicate with each other using the first distribution line 91. However, communication between houses with different service lines and backup lines, specifically between house 200A and house 200C, between house 200A and house 200D, between house 200B and house 200C, and between house 200B and house 200D, I can't do it.

Further, even in a house 200B, for example, the switch section S ₅ in an accident such as wiring is connected to the house 200B 91B 'is disconnected is turned off, when the switch portion S ₁ is connected to the house 200A is on, House 200B cannot communicate with the outside or communicate with house 200A.

  Therefore, a main object of the present invention is to provide a power line carrier communication system capable of performing communication using a high frequency signal even when the power line is cut off by a switch or the like. Another object of the present invention is to provide a power line carrier communication coupler suitable for use in the above system.

  In order to achieve the above object, the present invention proposes two types of systems. A 1st form is a structure which couple | bonds between the supply side and demand side of a switch part provided in the power line in high frequency.

  That is, the power line carrier communication system of the present invention includes a first house and a second house that perform power line carrier communication, and a first distribution line and a second distribution line that can supply power to both the first house and the second house. With The first distribution line includes a first switch part capable of cutting off power supply from the first distribution line to the first house, and a third switch part capable of cutting off power supply from the first distribution line to the second house. Is provided. When the first switch part is on, the second distribution line cuts off the power supply from the second distribution line to the first house, and when the first switch part is off, it supplies power to the first house. When the second switch part and the third switch part are enabled, the power supply from the second distribution line to the second house is cut off, and when the third switch part is off, the power supply to the second house is performed. A fourth switch part is provided to enable the above. A first power line carrier communication device is arranged on at least one demand side or supply side of the first switch unit and the second switch unit. Among the third switch part and the fourth switch part, the second power line carrier communication apparatus is provided on the demand side or the supply side of the switch part provided on the same distribution line as the distribution line on which the first power line carrier communication apparatus is arranged. Deploy. And when the switch part provided in the distribution line by which the said 1st power line carrier communication apparatus is arrange | positioned is OFF, between the supply side and demand side of this switch part is high-frequency-coupled, and a 1st house communicates by a high frequency signal It comprises a first coupler that allows it to be performed. And when the switch part provided in the distribution line in which the second power line carrier communication device is arranged is off, the supply side and the demand side of the switch part are coupled at high frequency, and the second house communicates with the high frequency signal. It comprises a second coupler that allows it to be performed.

  With the above configuration, even if the first house and the second house are different in service line and backup line, the supply side and the demand side of the switch unit are coupled with each other at high frequency. Communication can be performed. Specifically, for example, the first house uses the first distribution line as a service line, the second house uses the first distribution line as a backup line, and the first distribution line is referred to as a first power line carrier communication device (hereinafter referred to as a PLC modem). ) And a second PLC modem. At this time, even if the first switch unit is on and the third switch unit is off, the supply side and the demand side of the third switch unit are high-frequency coupled by the second coupler. High-frequency signal communication between the modem and the second PLC modem is possible. That is, the second house can use the first distribution line as a signal transmission path, and can communicate with the first house. Therefore, when any PLC modem is connected to the backbone network, both the first house and the second house can communicate with the backbone network. That is, communication with the backbone network can be performed even in a house where the connection point with the backbone network is remote.

  For example, the first house and the second house have the same service line and backup line, the first distribution line is the service line, the second distribution line is the backup line, and the first distribution line is the first PLC. Consider the case with a modem and a second PLC modem. At this time, even if the first switch part is on and the third switch part is turned off due to an accident or the like, the third switch part is coupled at a high frequency by the second coupler, The second house can perform communication using a high-frequency signal using the first distribution line.

  The second form is a configuration in which high frequency signals are injected / extracted to both the service line and the backup line.

  That is, the power line carrier communication system of the present invention includes a first house and a second house that perform power line carrier communication, and a first distribution line and a second distribution line that can supply power to both the first house and the second house. With The first distribution line includes a first switch part capable of cutting off power supply from the first distribution line to the first house, and a third switch part capable of cutting off power supply from the first distribution line to the second house. Is provided. When the first switch part is on, the second distribution line cuts off the power supply from the second distribution line to the first house, and when the first switch part is off, it supplies power to the first house. When the second switch part and the third switch part are enabled, the power supply from the second distribution line to the second house is cut off, and when the third switch part is off, the power supply to the second house is performed. A fourth switch part is provided to enable the above. A third power line carrier communication device capable of injecting a high frequency signal and extracting a high frequency signal is provided on both the supply side of the first switch unit and the supply side of the second switch unit. In addition, a fourth power line carrier communication device capable of injecting a high frequency signal and extracting a high frequency signal is provided on both the supply side of the third switch unit and the supply side of the fourth switch unit.

  With the above configuration, even if the first house and the second house are different in service line and backup line, high-frequency signals are transmitted to both the first distribution line and the second distribution line. Communication using high-frequency signals can be performed. In particular, in this embodiment, since a high frequency signal can be injected into both the first distribution line and the second distribution line / high frequency signals can be extracted from both the first distribution line and the second distribution line with a single PLC modem. No PLC modem is placed on both the first distribution line and the second distribution line. In the first embodiment, when both the first distribution line and the second distribution line are used as signal transmission lines, it is necessary to arrange PLC modems on both the first distribution line and the second distribution line. In the embodiment, even if both the first distribution line and the second distribution line are used as signal transmission lines, only one PLC modem is required for both distribution lines, and the number of PLC modems can be reduced. In the second mode, since both the first distribution line and the second distribution line are used as signal transmission lines, even if an accident such as one of the distribution lines is broken, the other distribution line is used to generate high frequency. Communication using signals can be performed. Specifically, for example, consider a case where the first house has the first distribution line as the service line, the second house has the first distribution line as the backup line, and the first distribution line is disconnected. At this time, in the 1st house, the 1st switch part provided in the 1st distribution line is OFF, the 2nd switch part provided in the 2nd distribution line is ON, and in the 2nd house, it is provided in the 2nd distribution line. In addition, the fourth switch unit is turned on, and the first house and the second house can communicate with the high-frequency signal using the second distribution line as a signal transmission path.

  Of course, in the second embodiment, as in the first embodiment, when either the third PLC modem or the fourth PLC modem is connected to the backbone network, both the first house and the second house are connected to the backbone network. Communication is possible.

  As described above, in any of the embodiments, the present invention enables communication using a high-frequency signal regardless of opening and closing of the switch unit provided in the power line.

Hereinafter, the present invention will be described in more detail.
The first house and the second house are in a state where power line carrier communication is possible. Therefore, the first house and the second house have, for example, a terminal device such as a personal computer capable of transmitting and receiving a high-frequency signal, a PLC modem that injects a high-frequency signal into the terminal device, and extracts a high-frequency signal from the terminal device. . As this PLC modem, a known one used as a so-called child modem may be used.

  The first distribution line and the second distribution line are power lines that can supply power to the first house and the second house. For example, a high voltage distribution line of 6 kV or more may be used, and a known three-phase three-wire high voltage distribution line may be used. Moreover, it is good also as a structure which provides a shield layer in the outer periphery of a conductor. High-voltage distribution lines with shield layers are used for underground cables buried underground.

  When the first distribution line and the second distribution line are high-voltage distribution lines, the power supply to each house is done by a transformer that can transform the voltage applied to the first distribution line and the second distribution line, and a transformer. It is good also as a structure performed via the low voltage | pressure line which can supply the transformed electric power to a house. For example, it is good also as a structure which transforms from 6kV or more to 100V or 200V with a transformer, and supplies electric power to each house. At this time, between the transformer and the first distribution line, and between the transformer and the second distribution line may be connected by wiring, and each switch unit described later may be provided on these wirings.

  The first distribution line includes a first switch part that can cut off power supply from the first distribution line to the first house, and a third switch part that can cut off power supply from the first distribution line to the second house. Is provided. In addition, when the first switch part is on, the second distribution line cuts off the power supply from the second distribution line to the first house, and when the first switch part is off, the power supply to the first house When the second switch part and the third switch part are enabled, the power supply from the second distribution line to the second house is cut off. When the third switch part is off, the power to the second house is cut off. A fourth switch part that enables supply is provided. With this configuration, when the first switch unit is on, the first switch unit is turned off, power is supplied from the first distribution line, and when the first switch unit is off, the second switch unit is Turns on and power is supplied from the second distribution line. In the second house, when the third switch part is on, the fourth switch is off, power is supplied from the first distribution line, and when the third switch part is off, the fourth switch part is on, Power is supplied from the distribution line.

  In the first embodiment, the first PLC modem is arranged on the demand side or the supply side of at least one of the first switch part and the second switch part. In the conventional system shown in FIG. 11, when a PLC modem is arranged on the supply side of the switch unit, when the switch unit is turned off, the house is cut off from the PLC modem, so communication using a high-frequency signal cannot be performed. . On the other hand, in the present invention, since the demand side and the supply side of the switch unit are coupled at a high frequency by a coupler which will be described later, even if the PLC modem is arranged on either the demand side or the supply side of the switch unit, the switch Communication with a high-frequency signal can be performed regardless of whether the unit is opened or closed.

  Further, the first PLC modem may be arranged on both the demand side (supply side) of the first switch unit and the demand side (supply side) of the second switch unit. At this time, the first house can use both the first distribution line and the second distribution line as signal transmission paths.

  On the other hand, a 2nd PLC modem is arrange | positioned at the demand side or supply side of the switch part provided in the same distribution line as the distribution line where a 1st PLC modem is arrange | positioned among the said 3rd switch part and a 4th switch part. For example, when the first PLC modem is provided on the supply side (demand side) of the first switch unit, the first PLC modem is disposed on the first distribution line, and therefore, among the third switch unit and the fourth switch unit. The second PLC modem is arranged on the supply side (demand side) of the third switch unit provided in the first distribution line. When the first PLC modem is arranged on the supply side (demand side) of both the first switch unit and the second switch unit, and both the first distribution line and the second distribution line are used as signal transmission lines, the third A second PLC modem is disposed on the supply side (demand side) of both the switch unit and the fourth switch unit.

  On the other hand, in the second embodiment, the supply side of the first switch unit, and the supply side of the first switch unit, and the supply side of the second switch unit, so that the high frequency signal can be injected and the high frequency signal can be extracted, and A third PLC modem is arranged on both the supply side of the second switch section. Further, the supply side of the third switch part and the extraction of the high frequency signal can be injected into both the supply side of the third switch part and the supply side of the fourth switch part and the high frequency signal can be extracted. A fourth PLC modem is placed on both the supply side. With the above arrangement, the first house and the second house can use both the first distribution line and the second distribution line as signal transmission paths.

  As the first PLC modem to the fourth PLC modem, a known PLC modem used as a so-called parent modem may be used. The first PLC modem to the fourth PLC modem include, for example, a power supply circuit for obtaining power for operating each component such as a transmission / reception unit and a transmission / reception unit for receiving a high-frequency signal or transmitting a signal. Examples include a power supply unit. In addition, when performing communication with the outside, a function necessary for communication with the outside, specifically, a LAN interface such as 10Base or 100Base may be provided.

  The feature of the first embodiment is that when the switch section provided on the distribution line on which the PLC modem is arranged is off, the supply side and the demand side of the switch section are coupled at high frequency to perform communication by a high frequency signal. It is in that it has a coupler that enables it. As such a coupler, any low frequency current for power supply (usually commercial frequency, for example, 50 Hz, 60 Hz current) can be cut off and any high frequency current that can be a high frequency signal can be transmitted. For example, the structure using a capacitor is mentioned as a structure directly connected to the 1st distribution line and the 2nd distribution line. When using a capacitor, if the first distribution line and the second distribution line are high voltage lines such as 6 kV or more, there is a risk of failure depending on the capacity. Therefore, as a configuration that does not use a capacitor, a configuration in which high-frequency signals can be injected / extracted without contact with the first distribution line and the second distribution line can be given. For example, the structure which can energize via magnetism using the principle of electromagnetic induction is mentioned. Specifically, a pair of first and second ferromagnets, a first winding and a second winding that are arranged on the first and second ferromagnets, respectively, and transmit high-frequency signals. There is a configuration that includes a line and a circuit that connects the first winding and the second winding, interrupts a low-frequency current such as a power supply current, and passes a high-frequency signal. As a circuit for connecting the first winding and the second winding, for example, a configuration in which capacitive coupling is performed by a capacitor can be given.

  The first ferromagnet and the second ferromagnet are arranged on the supply side and the demand side of the switch unit provided in the distribution line on which the first PLC modem and the second PLC modem are arranged, respectively. At this time, if the conductor of the distribution line on which the first PLC modem and the second PLC modem are arranged is a signal transmission line, current does not flow through the conductor when the switch section provided on the distribution line is off. The supply side and the demand side of the switch unit cannot be coupled at a high frequency. Therefore, when using a coupler including the ferromagnetic material and the winding, the distribution line on which the first PLC modem and the second PLC modem are arranged includes a shield layer, and this shield layer is used as a signal. It is preferable to use it as a transmission line. This shield layer is grounded on the supply side and the demand side of the switch unit provided on the distribution line on which the first PLC modem and the second PLC modem are arranged, and the first ferromagnetic layer is sandwiched between these grounding points. The body and the second ferromagnet are arranged respectively. Further, in this shield layer, the side away from the switch portion from the location of each ferromagnetic material is grounded, so that a closed loop with the ground is formed on each of the supply side and the demand side of the switch portion. The supply side and the demand side of the switch unit can be high-frequency coupled via the winding and the second winding.

  When the first ferromagnet and the second ferromagnet are respectively arranged on the supply side and the demand side of the switch unit provided in the distribution line in which the first PLC modem and the second PLC modem are arranged, the switch unit When is turned off, no current for supplying power (usually commercial current) flows in each ferromagnetic body. Therefore, magnetic flux saturation does not occur in the ferromagnetic bodies due to the current for supplying power, and high-frequency coupling can be performed efficiently. On the other hand, when the switch unit is turned on, a current for supplying power flows in each of the ferromagnetic bodies, and this current causes magnetic flux saturation in these ferromagnetic bodies. However, since the switch portion is closed, it is possible to energize, so communication can be performed using the first distribution line and the second distribution line. Therefore, according to the present invention, communication using a high-frequency signal can be performed regardless of opening / closing of a switch unit provided in a distribution line in which the first PLC modem and the second PLC modem are arranged.

  As the ferromagnetic material, it is preferable to use a ferrite core having a high magnetic permeability even at a high frequency. In particular, when a ferrite core is used, the signal frequency is preferably 4 MHz or more in order to further improve the high-frequency coupling characteristics. FIG. 9 is a graph showing the relationship between frequency and attenuation. As shown in the graph of FIG. 9, the amount of attenuation decreases as the frequency increases, and the amount of attenuation is substantially constant at about 4 MHz. The ferrite core is preferably annular and may have an integral structure. However, it is preferable that the ferrite core be formed into an annular shape by combining the divided pieces.

  The first PLC modem and the second PLC modem may be directly connected to the first distribution line (second distribution line) or the wiring connecting the transformer and the first distribution line (second distribution line), High frequency signals may be injected / extracted without contact with these power lines. In the latter case, for example, high-frequency signals may be injected / extracted via magnetism using the principle of electromagnetic induction. At this time, at least one of the first PLC modem and the second PLC modem has a third ferromagnet disposed on the distribution line and a third volume disposed on the third ferromagnet to transmit a high-frequency signal. Preferably it comprises a line. Both the first PLC modem and the second PLC modem may each include the ferromagnetic material and the winding. A known inductive coupler including a ferromagnetic material and a winding may be used. As the third ferromagnetic material, a ferrite core is preferable.

  When the first PLC modem and the second PLC modem are equipped with a third ferromagnetic material and a third winding to inject / extract high-frequency signals, the switch provided on the distribution line on which these modems are placed is turned on. Then, a current for supplying power (usually a commercial current) flows through the distribution line. Therefore, it is desirable that the ferromagnetic material not be magnetically saturated with a magnetic flux generated by a current for supplying power. As a countermeasure, it is possible to provide a configuration that can cancel (cancel) the magnetic field applied by the current for supplying power. For example, in addition to the third winding, the third ferromagnetic body may include a cancel winding configured to allow a current having a frequency different from the frequency of the high-frequency current flowing in the third winding to flow. The frequency of the current flowing in the cancel winding is preferably relatively lower than the frequency of the high-frequency current flowing in the third winding, for example, a commercial frequency. You may utilize the structure described in Unexamined-Japanese-Patent No. 2001-319815.

  The coupler is configured to connect directly to the first distribution line and the second distribution line using a capacitor, and the third ferromagnetic body and the third winding are provided in the first PLC modem and the second PLC modem. In this case, the conductors of the first distribution line and the second distribution line may be used as signal transmission paths. On the other hand, when the coupler is configured to inject / extract high-frequency signals without contact with the first distribution line and the second distribution line using the principle of electromagnetic induction, the first distribution line and the second distribution line May include a shield layer, and the shield layer may be a signal transmission path.

In the second mode, connect the third PLC modem and the fourth PLC modem to the power line (first distribution line, second distribution line, or wiring connecting the transformer and the first distribution line, connecting between the transformer and the second distribution line. May be directly connected to the wiring). At this time, when the conductor of the power line is used as a signal transmission line, the conductor is usually supplied with a voltage such as AC100V or AC200V at a frequency (usually commercial frequency) necessary for power supply in order to supply power. Yes. For this reason, when the third PLC modem and the fourth PLC modem are directly connected to the conductor of the power line, the first distribution line and the second distribution line are connected by this connection, and a short circuit occurs between these distribution lines. Therefore, in order to effectively prevent short-circuit accidents between these distribution lines, high-frequency signal injection / extraction points on the supply side of the switch section provided on the first distribution line, and switches provided on the second distribution line Preferably, a filter that cuts off a current having a specific frequency is provided between the signal injection / extraction points on the supply side of the unit. Specific examples of the filter include a high-pass filter that easily cuts off the frequency of the current for supplying power and easily passes the signal frequency (high frequency). More specifically, a capacitor is mentioned, for example. Examples of the capacitor include a capacitor having a capacity of 10 ⁻³ to 10 ³ μF, particularly preferably a capacitor having a capacity of 10 ⁻² to 10 μF when the frequency of the high-frequency signal is ^{2 to} 30 MHz.

  At least one of the third PLC modem and the fourth PLC modem is connected to the power line (the first distribution line, the second distribution line, or the wiring connecting the transformer and the first distribution line, between the transformer and the second distribution line. A configuration may be employed in which high-frequency signals are injected / extracted in a non-contact manner without being directly connected to the wiring to be connected). For example, a configuration that can be energized via magnetism using the principle of electromagnetic induction may be used. Specifically, a pair of sixth ferromagnet and seventh ferromagnet disposed on the supply side of the switch unit provided in the first distribution line and on the supply side of the switch unit provided in the second distribution line, respectively. And a sixth winding and a seventh winding which are respectively disposed on the sixth ferromagnetic body and the seventh ferromagnetic body and transmit a high-frequency signal. The sixth ferromagnet and the seventh ferromagnet are preferably ferrite cores having high permeability even at high frequencies. The sixth winding and the seventh winding may be capacitively coupled by a capacitor. With the above configuration, the high frequency signal is supplied to both the supply side of the switch unit provided in the first distribution line and the supply side of the switch unit provided in the second distribution line via the sixth winding and the seventh winding. High-frequency signals can be extracted from both the injection and both. Both the third and fourth PLC modems may include the sixth ferromagnetic material, the seventh ferromagnetic material, the sixth winding, and the seventh winding, respectively. Thus, when injecting / extracting a high-frequency signal without contact with the power line, the first distribution line and the second distribution line may include a shield layer, and the shield layer may be used as a signal transmission path.

  Consider a case where the first distribution line and the second distribution line are high-voltage distribution lines (for example, 6 kV or more), transformed by a transformer, and power is supplied to each house via the low-voltage line. That is, a transformer capable of transforming a voltage applied to the first distribution line and the second distribution line between the switch unit provided on the first distribution line and the switch unit provided on the second distribution line and the house; Consider a case where a low-voltage line capable of supplying electric power transformed by a transformer to a house is provided. At this time, the high-frequency signal transmitted from the backbone network or the like to the first distribution line and the second distribution line is blocked by the transformer, the signal is not transmitted to the low-voltage line, and is difficult to transmit to the house. Moreover, the high frequency signal transmitted from the house to the low voltage line is similarly blocked by the transformer, and it is difficult to transmit the signal to the first distribution line and the second distribution line. Therefore, it is desired to provide a bypass mechanism that bypasses the transformer and enables communication using a high-frequency signal between the first distribution line, the second distribution line, and the low-voltage line on which the PLC modem is arranged. For example, the first distribution line (second distribution line) and the low-voltage line may be directly connected. At this time, when the first distribution line (second distribution line) is a three-phase three-wire system, a capacitor and a resistor connected in series to the capacitor are arranged between the phases of the first distribution line (same), and A configuration is possible in which both ends of the resistor are connected to a low-voltage line. The configuration described in Patent Document 1 may be used.

  As described above, the first distribution line (second distribution line) and the low-voltage line may be directly connected, but these power lines may be coupled in a high-frequency manner without contact. For example, a configuration that can be energized via magnetism using the principle of electromagnetic induction may be used. Specifically, fourth and fifth ferromagnets (eighth ferromagnet and ninth ferromagnet) placed on the low-voltage line on the demand side of the transformer and the distribution line on the supply side of the transformer, respectively. Body), and fourth and fifth windings (eighth winding and ninth winding), which are respectively disposed in the fourth and fifth ferromagnetic bodies (same), and in which high-frequency signals are transmitted. The structure which comprises is mentioned. The fourth ferromagnet (eighth ferromagnet) and the fifth ferromagnet (ninth ferromagnet) are preferably ferrite cores having high permeability even at high frequencies. Further, the fourth winding and the fifth winding (the eighth winding and the ninth winding) are connected so as to transmit a high-frequency signal. With the above configuration, a high frequency is generated between the low-voltage line on the demand side of the transformer and the distribution line on the supply side of the transformer via the fourth winding (eighth winding) and the fifth winding (ninth winding). Allows signal transmission. At this time, if the conductor is a signal transmission line in the first distribution line (second distribution line), a signal cannot be transmitted to the distribution line when the switch portion provided in the distribution line is off. Therefore, it is preferable that the first distribution line and the second distribution line include a shield layer and use the shield layer as a signal transmission path. The low voltage line does not need to have a shield layer, and the conductor is preferably a signal transmission line.

  The fourth and fifth ferromagnets may be included in the first PLC modem (second PLC modem). Further, an eighth ferromagnet and a ninth ferromagnet may be provided in the third PLC modem (fourth PLC modem). At this time, the first PLC modem (second PLC modem) and the third PLC modem (fourth PLC modem) function as a repeater that outputs a signal having a frequency different from that of the received signal to the low-voltage line. In addition, when the bypass mechanism including the ferromagnetic material and the winding and the PLC modem are separately provided, the PLC modem can communicate without using the repeater function. In addition, for example, only when the first PLC modem is provided and the second PLC modem is not provided, the second house can transmit a high-frequency signal from the first distribution line (second distribution line) to the low-voltage line. The house may include only a bypass mechanism including the ferromagnetic material and the winding. Similarly, for example, when only a third PLC modem is provided and a high frequency signal can be transmitted from the first distribution line (second distribution line) to the low-voltage line in the second house without the fourth PLC modem, The second house may include only a bypass mechanism including the ferromagnetic body and the winding.

  As described above, according to the system of the present invention, between houses connected by a power line, even if the switch part provided on the power line is closed and the house is shut off, the power line is used. An excellent effect that communication using a high-frequency signal can be performed can be achieved. Therefore, for example, a high voltage distribution line that switches between a service line and a backup line by a switch unit can be used as the power line. Thus, by using the high-voltage distribution line laid in a wide area as a signal transmission line, power line carrier communication is enabled via the high-voltage distribution line even in an area where the backbone network is not expanded. The coupler of the present invention contributes to the construction of the above-described system of the present invention.

  Embodiments of the present invention will be described below.

FIG. 1 is an explanatory view schematically showing an outline of the first embodiment in the power line carrier communication system of the present invention. In this example, a case where a high-voltage distribution line 90 having a service line and a backup line is used as a signal transmission line is shown. The high-voltage distribution line 90 includes a first distribution line 91 and a second distribution line 92. In this example, power supply to each of the houses 200A to 200D is performed from the high voltage distribution line 90 through the low voltage distribution lines (low voltage lines) 100A to 100D via the transformers 95A to 95D, respectively. Between each transformer 95A-95D and the 1st distribution line 91, between each transformer 95A-95D and the 2nd distribution line 92, respectively, wiring 91A'-91D 'which can supply electric power, 92A'-92D 'are connected by the wiring 91A'～91D', each of the 92A'～92D ', comprises a switch unit S ₁ to S ₈ capable of interrupting the power supply to each house 200A through 200D.

Houses 200A and 200B are, among the high-voltage distribution lines 90, the first distribution line 91 serves as a service line, the second distribution line 92 serves as a backup line, and a wiring 91A that connects between the transformers 95A and 95B and the first distribution line 91. The switch portions S ₁ and S ₅ are provided in ', 91B', respectively. In addition, when the switches S ₁ and S ₅ are turned on to the wirings 92A ′ and 92B ′ connecting the transformers 95A and 95B and the second distribution line 92, respectively, the second distribution line 92 to the houses 200A and 200B It has switch parts S ₂ and S ₆ for cutting off the power supply. FIG. 1 shows a case where the switch units S ₁ and S ₅ are on and the switch units S ₂ and S ₆ are off.

The houses 200C and 200D are houses that have different service lines and backup lines from the houses 200A and 200B. That is, in the houses 200C and 200D, among the high-voltage distribution lines 90, the first distribution line 91 is a backup line and the second distribution line 92 is a service line. Then, the switch portions S ₃ and S ₇ are provided on the wirings 91C ′ and 91D ′ connecting the transformers 95C and 95D and the first distribution line 91, respectively. In addition, when the switch sections S ₃ and S ₇ are turned on to the wirings 92C 'and 92D' connecting the transformers 95C and 95D and the second distribution line 92, respectively, the second distribution line 92 to the house 200C and 200D The switch units S ₄ and S ₈ for cutting off the power supply are provided. FIG. 1 shows a case where the switch units S ₃ and S ₇ are off and the switch units S ₄ and S ₈ are on.

Each house 200A to 200D is a house capable of power line communication, and a terminal device (not shown) such as a personal computer, and a PLC modem (so-called high frequency signal injection / extraction from the terminal device to the terminal device) Child modem (not shown). On the other hand, PLC modems (so-called parent modems) 501A and 501B are provided on the demand side of the switch units S ₁ and S ₅ , respectively. Further, the same distribution line as that on which the PLC modems 501A and 501B are arranged, that is, the PLC modem (so-called parent modem) on the demand side of the switch units S ₃ and S ₇ provided on the first distribution line 91, respectively. Has 501C and 501D. In this example, these PLC modems 501A to 501D are directly connected to the conductors of the wirings 91A ′ to 91D ′, respectively. In this example, it is assumed that only the PLC modem 501A is connected to the backbone network NT, and the backbone network NT is constructed of an optical fiber network using the optical fiber cable 400. Further, the PLC modem 501A has a built-in MC that performs optical / electrical signal conversion. The high-voltage distribution line 90 including the wirings 91A ′ to 91D ′ and 92A ′ to 92D ′ is a three-phase three-wire system, and includes a shield layer on the outer periphery of the conductor.

Houses 200A is normal, the switch section S ₁ is turned on, the switch section S ₂ is turned off, the power supply is made from the first distribution line 91. At this time, the house 200A can also communicate with the backbone network NT using the PLC modem 501A included in the first distribution line 91 (wiring 91A ′). Also, house 200B which have the same service lines and backup lines and houses 200A also normal, the switch section S ₅ is turned on, the switch section S ₆ is turned off, the power supply is performed by the first distribution line 91, PLC modem The high frequency signal transmitted to the first distribution line 91 can be extracted using 501B / injection of the high frequency signal into the first distribution line 91 is possible. Therefore, the house 200B can perform high-frequency signal communication with the house 200A and the backbone network NT using the first distribution line 91 as a signal transmission path. On the other hand, in the houses 200C and 200D where the service line and the backup line are different from the house 200A, the switch units S ₃ and S ₇ provided in the first distribution line 91 are normally disconnected from the first distribution line 91 in the normal state. In this state, communication using a high-frequency signal cannot be performed using the first distribution line 91 as a signal transmission path. Also in homes 200B, when the switch portion S ₁ is ON, there is a case where the switch portion S ₅ is turned off. Even in such a case, in the present invention, the first distribution line 91 provided with the PLC modems 501A to 501D is provided in order to enable communication using a high-frequency signal using the first distribution line 91 as a signal transmission path. The switch units S ₁ , S ₅ , S ₃ and S ₇ are coupled at high frequency between the supply side and the demand side by couplers 1A to 1D.

Due to this connection, regardless of whether the switch parts S ₁ , S ₅ , S ₃ , S ₇ are opened or closed, the houses having different service lines and backup lines, that is, between the houses 200A and 200C, between the houses 200A and 200D, and between the houses Communication between the 200B and the house 200C and between the house 200B and the house 200D is possible using the first distribution line 91 as a signal transmission path. In addition, when the service line and the backup line are in the same house, the switch part of one house is opened, so that communication using a high-frequency signal is possible even when the house is disconnected from the other house.

For example, in a house 200A and house 200C, the switch section S ₁ is turned on, when the switch portion S ₃ is turned off, the high-frequency signal from the house 200C is the first distribution line 91 via the coupler 1C from the PLC modem 501C transmission Then, it is transmitted from the wiring 91A ′ to the house 200A and the backbone network NT via the PLC modem 501A. Further, the high frequency signal transmitted from the house 200A and the backbone network NT to the first distribution line 91 is extracted from the wiring 91C ′ via the coupler 1C by the PLC modem 501C and transmitted to the house 200C. On the other hand, when the switch portion S ₁ is turned off, the switch section S ₃ is turned on, the high-frequency signal from the house 200C is 'transmitted to the first distribution line 91 via the wiring 91A' wire 91C from the PLC modem 501C → coupler 1A is transmitted to the house 200A and the backbone network NT via the PLC modem 501A. The high frequency signal transmitted from the house 200A or the backbone network NT via the PLC modem 501A is transmitted to the first distribution line 91 via the coupler 91A via the wiring 91A ', and then via the wiring 91C' to the PLC modem 501C. Extracted to the house 200C.

In the example shown in FIG. 1, the couplers 1A to 1D are arranged only in the switch portions S ₁ , S ₅ , S ₃ , and S ₇ provided in the wirings 91A ′ to 91D ′. The switch units S ₂ , S ₆ , S ₄ , S ₈ provided in the above are also provided with the above couplers, and a PLC modem is provided on the demand side of the switch units S ₂ , S ₆ , S ₄ , S _8. Also good. At this time, in addition to the first distribution line 91, the second distribution line 92 can also be used as a signal transmission line, and even if the wirings 91A ′ to 91D ′ and the first distribution line 91 cannot be used due to disconnection or the like. Communication by high frequency signal can be performed. Further, in this embodiment, the switch unit _{S 1, S 5, S 3} , an example is shown comprising a PLC modem 501A~501D the demand side of the S _7, the switch portion _{S 1, S 5, S 3} , S 7 The supply side may be used.

  A specific example of the coupler 1 will be described. FIG. 2 is an enlarged view of the coupler portion. In this example, a configuration using the principle of electromagnetic induction is shown as the coupler 1. Specifically, a high-frequency signal is transmitted by being wound around a pair of ferrite cores 2a and 2b and cores 2a and 2b respectively arranged on the supply-side wiring 91 ′ and the demand-side wiring 91 ′ of the switch unit S Windings 3a and 3b, and a capacitor 4 that capacitively couples the windings 3a and 3b. The capacitor 4 can cut off a low-frequency power supply current and efficiently pass a high-frequency signal.

  When the coupler 1 is arranged on the supply side and the demand side of the switch unit S and the switch unit S is open as shown in FIG. 2, the wiring 91 ′ is in a cut-off state, so that the current for supplying power is It does not flow from the supply side to the demand side. Therefore, the cores 2a and 2b can be efficiently high-frequency coupled without causing magnetic saturation due to the magnetic flux generated by the power supply current. At this time, if the frequency of the high-frequency signal is 4 MHz or more, a large coupling efficiency can be obtained.

  On the other hand, when the switch unit S is closed, the wiring 91 ′ is in a connected state, so that a power supply current flows from the supply side to the demand side. Therefore, the cores 2a and 2b cause magnetic flux saturation due to the current for supplying power. However, since the switch portion S is closed, communication using a high-frequency signal can be performed using the wiring 91 ′.

When the coupler 1 is used, the signal transmission path preferably uses a shield layer provided on the outer periphery of the conductor instead of the conductor of the wiring 91 ′. Here, a case where communication using a high-frequency signal is performed between the house 200A and the house 200C will be described as an example. FIG. 3 is an explanatory diagram schematically showing the flow of a high-frequency signal when the shield layer is used as a signal transmission path. Wires 91A ', 91C', conductor 93, comprising a shield layer 94 on the outer periphery of the conductor 93 is grounded by a ground line 96 of the supply side and the demand side of the switch section S ₃ in the shielding layer 94 of the wiring 91C '. Then, the cores 2a and 2b of the coupler 1 are arranged so as to sandwich both grounded portions. Note that the wiring 91C 'side away from the switch section S ₃ in the shielding layer 94 (on the left in FIG. 3), and the wiring 91A' the shield layer 94 of grounded by respective ground line 96.

With this configuration, in both the supply side and the demand side of the switch section S _3, the shield layer 94, and ground and closed loop is formed through the ground line 96 which is attached to the shield layer 94, the high frequency signal is in this closed loop Is transmitted. That is, even if the open switch section S _3, the supply side of the switch section S _3, the high-frequency signal is transmitted to both the demand side. In FIG. 3, the two-dot chain line indicates the flow of the high-frequency signal.

  When the shield layer 94 is used as the signal transmission path as described above, the PLC modems 501A and 501C perform injection / extraction of the high frequency signal from the shield layer 94 to the shield layer 94 of the wirings 91A ′ and 91C ′, respectively. Arrange so that you can. For example, it may be directly connected to the shield layer 94 as in the PLC modem 501C shown in FIG. 3, or may be configured to be able to inject / extract high-frequency signals without contact with the wiring 91A ′ as in the PLC modem 501A. . In this example, the PLC modem 501A is provided with an inductive coupler 10 for injecting / extracting a high-frequency signal using the principle of electromagnetic induction. The inductive coupler 10 includes a ferrite core 11 disposed on the wiring 91A ′ and a winding 12 that is wound around the core 11 and transmits a high-frequency current. In addition to the winding 12, the ferrite core 11 of the inductive coupler 10 may be provided with a cancel winding that can flow a current that cancels the magnetic field due to the current for supplying power. At this time, even if a current for supplying power flows through the wiring 91A ′, the magnetic field due to the current for supplying power is canceled by the cancel winding, so that a stable level signal can be extracted.

  A method for transmitting a high-frequency signal between the high-voltage distribution line 90 and the low-voltage distribution line 100 will be described. FIG. 4 is a schematic configuration diagram schematically showing a state in which a PLC modem is arranged on both the high-voltage distribution line and the low-voltage distribution line so that high-frequency signals can be injected / extracted from both. As described above, the transformers 95A to 95D are provided between the high-voltage distribution line 90 and the low-voltage distribution line 100, and a large impedance is generated at high frequencies due to the leakage inductance of the transformers 95A to 95D. High-frequency signals are difficult to be transmitted from the electric wire toward the low-voltage distribution line. Therefore, it is preferable to provide a bypass mechanism that bypasses the transformers 95A to 95D so that a high-frequency signal can be efficiently transmitted between the high-voltage distribution line 90 and the low-voltage distribution line 100.

As the bypass mechanism, for example, as shown in a house 200C in FIG. 4, the PLC modem 501C may be directly connected to the low-voltage distribution line 100 so that a high-frequency signal can be injected from the PLC modem 501C to the low-voltage distribution line 100. Further, as shown in the house 200A, the PLC modem 501A may be provided with a separate inductive coupler 13 so that high-frequency signals can be injected into the low-voltage distribution line 100 without contact. The inductive coupler 13 includes a configuration including a ferrite core 14 disposed on the low-voltage distribution line 100 and a winding 15 wound around the ferrite core 14 to transmit a high-frequency signal. Then, the demand side the ferrite core 11 of the switch section S ₁ of the inductive coupler 10, i.e., disposed on the wiring 91 'of the interphase transformer 95A and the switch section S _1, the demand for the transformer 95 and the ferrite core 14 of the inductive coupler 13 It is arranged on the low-voltage distribution line 100 on the side. At this time, in the wiring 91A ′, the shield layer 94 may be a signal transmission path, and in the low-voltage distribution line 100, the conductor may be a signal transmission path. Note that the house 200B in FIG. 4 is illustrated in a simplified manner, but an example in which the inductive couplers 10 and 13 are provided in the PLC modem 501B as in the house 200A is shown.

  In this way, the PLC modem allows the high-frequency signal to be injected into both the high-voltage distribution line and the low-voltage distribution line, thereby bypassing the transformer and communicating with the high-frequency signal between the high-voltage distribution line and the low-voltage distribution line. It can be carried out.

  In the above example, the PLC modems 501A to 501C are examples in which the repeater function is used. However, when a high-frequency signal can be transmitted to the house without using the repeater function, the PLC modem 501A to 501C is illustrated in the house 200D in FIG. As described above, the PLC modem 501D may be arranged on the wiring 91D ′, and a bypass line BL connecting the low-voltage distribution line 100D and the wiring 91D ′ may be separately arranged to bypass only the signal. In addition, as shown in FIG. 5A, a high-frequency signal may be transmitted between the high-voltage distribution line (wiring 91 ′) and the low-voltage distribution line 100 by a bypass mechanism including the inductive coupler 16. The inductive coupler 16 includes ferrite cores 17a and 17b and cores 17a and 17b disposed on the shield layer 94 provided in the low-voltage distribution line 100 on the demand side of the transformer 95 and the wiring 91 ′ on the supply side of the transformer 95, respectively. And windings 18a and 18b through which high-frequency signals are transmitted. At this time, in the wiring 91 ′, the shield layer 94 may be a signal transmission path, and in the low-voltage distribution line 100, the conductor may be a signal transmission path.

  Further, as shown in FIG. 5B, a bypass mechanism including the inductive coupler 16 and a PLC modem 501 may be provided separately. At this time, the PLC modem 501 does not need a repeater function. 5B shows an example in which the inductive coupler 10 is provided in the PLC modem 501, the PLC modem 501 may be directly connected to the shield layer 94 of the wiring 91 ′ as shown in FIG. .

  By providing such a transformer bypass function, a high-frequency signal from the wiring 91 ′ is transmitted to the low-voltage distribution line 100 via the inductive coupler 16, as shown in FIG.

In this example, a configuration in which a single PLC modem performs high frequency signal injection / extraction from both the service line and the backup line will be described. FIG. 6 is an explanatory view schematically showing the outline of the power line carrier communication system of the present invention including a PLC modem for injecting / extracting a high frequency signal in both a service line and a backup line. High-voltage distribution line 90, a transformer 95a to 95d, low-voltage distribution lines 100A to 100D, the wiring 91A'~91D ', 92A'~92D', the basic configuration of a switch section S ₁ to S ₈ are performed as shown in FIG. 1 Same as Example 1. The feature of this example is that in each house 200A to 200D, the supply side of the switch parts S ₁ , S ₅ , S ₃ , S ₇ provided in the first distribution line 91 (wiring 91A ′ to 91D ′), and a second distribution line 92 (wiring 92A'~92D ') switching section S ₂ provided at, S _6, S _4, injection of high-frequency signals to both the supply side of the S ₈ and extraction capable PLC modem 502A~ The point is that each 502D is placed.

  With this configuration, in each of the houses 200A to 200D, high frequency signals can be injected / extracted from both the first distribution line 91 and the second distribution line 92 with one PLC modem. For example, a high frequency signal transmitted to the PLC modem 502A via the backbone network NT → the optical fiber cable 400 → the connection box 401 is injected into both the wirings 91A ′ and 92A ′ from the PLC modem 502A. By this injection, a high-frequency signal from the backbone network NT is transmitted to both the first distribution line 91 and the second distribution line 92. Therefore, in the houses 200B to 200D, high frequency signals can be extracted from both the first distribution line 91 and the second distribution line 92 by the PLC modems 502B to 502D. Therefore, the houses 200B to 200D can communicate with the backbone network NT. The high frequency signals transmitted from the houses 200A to 200D are injected into both the first distribution line 91 and the second distribution line 92 by the PLC modems 502A to 502D, and the high frequency signals are transmitted from the PLC modems 502A to 502D in the same manner as described above. Can be extracted, thus enabling communication between houses.

  As described above, similarly to the first embodiment, this form can perform power line carrier communication regardless of whether the switch unit is opened or closed. That is, for example, communication between a house 200C and a house 200C different in service line and backup line is possible. In this embodiment, one PLC modem can use both the first distribution line and the second distribution line as signal transmission paths. Therefore, even when any of the distribution lines and the wiring connected to the distribution lines cannot be used due to disconnection or the like, the power line carrier communication can be performed without providing a separate PLC modem.

Describes how to place a PLC modem. The PLC modems 502A to 502D may be directly connected to the wirings 91A ′ to 91D ′ and 92A ′ to 92D ′. In this case, the first distribution line 91 and the second distribution line 92 are connected. Short circuit. Therefore, in order to effectively prevent a short circuit, it is preferable to dispose a high-pass filter HPF that cuts off the power supply current and passes the signal high-frequency current as shown in FIG. High-pass filter HPF in the case of the example shown in FIG. 7, 'injection / extraction point P ₁ of the high-frequency signal in the wiring 92A of the supply side of the switch section S _2' wiring 91A of the supply side of the switch section S ₁ of the high-frequency signal in injection / extraction points may be arranged between the P _2. In this example, a high-pass filter composed of a capacitor having a capacitance of 10 μF was used.

  In addition, an inductive coupler may be provided in the PLC modem, and high-frequency signals may be injected / extracted without contact with the wiring. FIG. 8 is a schematic diagram showing a state in which a PLC modem having an inductive coupler is arranged in the wiring.

PLC modem 502A is a pair to be arranged 'supply side of the switch section S ₁ provided, and the wiring 92A' wiring 91A on the supply side of the switch section S ₂ provided at each ferrite core 21 shown in FIG. 8, And an inductive coupler 20 including windings 22 and 24 that are wound around the cores 21 and 23 to transmit a high-frequency current, and a capacitor 25 that capacitively couples the windings 22 and 24 to each other.

By providing the inductive coupler 20, when a high frequency current flows on the supply side of the switch units S ₁ and S _2, a magnetic field is generated and applied to the cores 21 and 23 by the current. A current according to the magnetic field and the magnetic permeability of the cores 21 and 23 flows through the windings 22 and 24, and the current can be extracted by the PLC modem 502A to perform communication. On the other hand, when a high-frequency current from the modem 502A flows through the windings 22 and 24, a magnetic field is generated and applied to the cores 21 and 23 by the current. A current corresponding to the magnetic field and the magnetic permeability of the cores 21 and 23 flows to the supply side of the switch portions S ₁ and S ₂ , and this is applied to both the first distribution line and the second distribution line from the wiring 91A ′ and the wiring 92A ′. Communication can be performed by transmitting the current. When a PLC modem is provided with an inductive coupler to inject / extract high-frequency signals, the signal transmission path is preferably a shield layer provided in the wirings 91A ′ and 92A ′.

  In the example shown in FIG. 8, since the PLC modem is arranged in a non-contact manner with respect to the wiring, the first distribution line and the second distribution line are not connected and are not short-circuited. Therefore, it is not necessary to provide a high pass filter.

  In this form as well, it is preferable to provide a bypass mechanism that bypasses the transformer as in the first embodiment. For example, as shown in FIG. 6, the PLC modems 502A to 502D are directly connected to the low-voltage distribution lines 100A to 100D, respectively, and signals are injected, or the PLC modems 502A to 502D are respectively connected to the PLC modems 501A and 501B shown in FIG. Similarly, a separate inductive coupler may be provided, and these couplers may be arranged in the low-voltage distribution lines 100A to 100D, respectively, and signal injection may be performed in a non-contact manner on the low-voltage distribution lines 100A to 100D. At this time, the PLC modems 502A to 502D also function as repeaters. Furthermore, if the repeater function is not required when bypassing the transformer, a bypass line connecting the low voltage distribution line and the wiring can be arranged in the same manner as the house 200D in FIG. 4, or an inductive as shown in FIG. Only a signal may be bypassed by providing a bypass mechanism including a coupler.

  The present invention is suitable when power line carrier communication is performed using a power transmission line in which power supply is interrupted by a switch or the like as a signal transmission path. In particular, it is optimal when performing power line carrier communication using a high-voltage distribution line as a signal transmission line.

It is explanatory drawing which shows typically the outline | summary of the structure which carries out high frequency coupling between the supply side and demand side of a switch part by a coupler in the power line carrier communication system of this invention. It is a schematic block diagram of the coupler for power line carrier communication of the present invention. It is explanatory drawing which shows typically the flow of a high frequency signal in the power line carrier communication system of this invention which used the shield layer as the signal transmission path. FIG. 2 is a schematic configuration diagram schematically showing a state in which a PLC modem is arranged so that high-frequency signals can be injected / extracted from both high-voltage distribution lines and low-voltage distribution lines. (A) is a bypass mechanism for bypassing a transformer in the power line carrier communication system of the present invention, and is an explanatory diagram showing an outline of a configuration including an inductive coupler, and (B) is a bypass mechanism including an inductive coupler and An explanatory view showing an outline of a configuration including a PLC modem, (C) is an explanatory view showing a flow of a high-frequency signal to the low-voltage distribution line side when a bypass mechanism including an inductive coupler is arranged. It is explanatory drawing which shows typically the outline | summary of the power line carrier communication system of this invention provided with the PLC modem which injects / extracts a high frequency signal to both a service line and a backup line. FIG. 7 is an explanatory diagram showing a state in which a high-pass filter is arranged between high-frequency signal injection / extraction points in the power line carrier communication system of the present invention shown in FIG. FIG. 7 is a schematic diagram showing a state in which a PLC modem including an inductive coupler is arranged in the wiring in the power line carrier communication system of the present invention shown in FIG. It is a graph which shows the relationship between the frequency of a signal, and attenuation amount. It is explanatory drawing which shows typically the outline | summary of the power line carrier communication system using a low voltage distribution line and a high voltage distribution line. It is explanatory drawing which shows typically the structure of the switch part vicinity provided in the high voltage distribution line in the power line carrier communication system using a low voltage distribution line and a high voltage distribution line.

Explanation of symbols

1,1A ~ 1D Coupler 2a, 2b Core 3a, 3b Winding 4 Capacitor
10,13,16,20 Inductive coupler 11,14,17a, 17b, 21,23 Ferrite core
12,15,18a, 18b, 22,24 Winding 25 Capacitor
90 High-voltage distribution line 91 First distribution line 91 ', 92', 91A 'to 91D', 92A 'to 92D' wiring
92 Second distribution line 93 Conductor 94 Shield layer 95, 95A to 95D Transformer
96 Ground wire
100,100A ~ 100D Low voltage distribution line 200A ~ 200D House 210A, 210B House
211A, 211B Indoor wiring 220 High voltage power line 230 First transformer room
231,241 Transformer
240 Second transformer room 250 Electricity meter room 260 Child modem 261 Relay modem
262 First parent modem 263 Second parent modem 270 Terminal equipment
400 Optical fiber cable 401 Junction box
501,501A ~ 501D, 502A ~ 502D PLC modem
NT backbone network P ₁ and P ₂ signal injection / extraction points
S, S _{1 to} S ₈ switch section

Claims (9)

A first house and a second house that perform power line carrier communication; and
A first distribution line and a second distribution line capable of supplying power to both the first house and the second house;
A first switch part provided in the first distribution line, capable of cutting off power supply from the first distribution line to the first house;
When the first switch part is on, the power supply from the second distribution line to the first house is cut off, and when the first switch part is off, the power to the first house is provided on the second distribution line. A second switch part enabling supply;
A third switch part provided in the first distribution line, capable of cutting off power supply from the first distribution line to the second house;
Provided in the second distribution line, when the third switch part is on, cuts off the power supply from the second distribution line to the second house, and when the third switch part is off, the power to the second house A fourth switch part enabling supply,
A first power line carrier communication device disposed on at least one demand side or supply side of the first switch part and the second switch part;
Of the third switch unit and the fourth switch unit, the second power line carrier disposed on the demand side or the supply side of the switch unit provided on the same distribution line as the distribution line on which the first power line carrier communication device is disposed. A communication device;
When the switch unit provided on the distribution line in which the first power line communication device is disposed is off, the supply side and the demand side of the switch unit are coupled at high frequency, and the first house performs communication using a high frequency signal. A first coupler that enables,
When the switch unit provided on the distribution line on which the second power line communication device is disposed is off, the supply side and the demand side of the switch unit are coupled at high frequency, and the second house performs communication using a high frequency signal. A power line carrier communication system comprising: a second coupler that enables The distribution line on which the first power line carrier communication device and the second power line carrier communication device are arranged includes a shield layer, and this shield layer is grounded on the supply side and the demand side of the switch unit,
Each of the first coupler and the second coupler is
A pair of first ferromagnet and second ferromagnet disposed so as to sandwich the both grounded portions;
The first and second ferromagnets, respectively, comprising a first winding and a second winding through which a high-frequency signal is transmitted;
2. The power line carrier communication system according to claim 1, wherein a high frequency signal is transmitted between a supply side and a demand side of the switch unit via the first winding and the second winding. At least one of the first power line carrier communication device and the second power line carrier communication device is
A third ferromagnetic material disposed on the distribution line;
3. The power line carrier communication system according to claim 1, further comprising a third winding disposed on the third ferromagnetic body and transmitting a high-frequency signal. Between the first house and the first switch part and the second switch part,
A first transformer capable of transforming a voltage applied to the first distribution line and the second distribution line;
Comprising a first low-voltage line capable of supplying the electric power transformed by the first transformer to the first house,
Bypassing the first transformer, comprising a first bypass mechanism that enables communication by a high-frequency signal between the distribution line and the first low-voltage line where the first power line carrier communication device is disposed,
Between the second house and the third switch part and the fourth switch part,
A second transformer capable of transforming a voltage applied to the first distribution line and the second distribution line;
A second low-voltage line capable of supplying the power transformed by the second transformer to the second house,
By providing a second bypass mechanism that bypasses the second transformer and enables communication by a high-frequency signal between a distribution line in which the second power line carrier communication device is arranged and the second low-voltage line. The power line carrier communication system according to any one of claims 1 to 3. The first low-voltage line arranged on the demand side of the first transformer and the second low-voltage line arranged on the demand side of the second transformer do not have a shield layer,
Among the distribution lines arranged on the supply side of the first transformer and the distribution lines arranged on the supply side of the second transformer, at least a distribution line in which the first power line carrier communication device and the second power line carrier communication device are arranged. The electric wire has a shield layer,
At least one of the first bypass mechanism and the second bypass mechanism is
A fourth ferromagnet and a fifth ferromagnet respectively disposed on the low-voltage line on the demand side of the transformer and the distribution line on the supply side of the transformer;
The fourth and fifth ferromagnets, respectively, comprising a fourth winding and a fifth winding through which a high-frequency signal is transmitted;
5. The power line carrier communication system according to claim 4, wherein a high-frequency signal can be transmitted between a supply side and a demand side of the transformer via the fourth winding and the fifth winding. A first house and a second house that perform power line carrier communication; and
A first distribution line and a second distribution line capable of supplying power to both the first house and the second house;
A first switch part provided in the first distribution line, capable of cutting off power supply from the first distribution line to the first house;
When the first switch part is on, the power supply from the second distribution line to the first house is cut off, and when the first switch part is off, the power to the first house is provided on the second distribution line. A second switch part enabling supply;
A third switch part provided in the first distribution line, capable of cutting off power supply from the first distribution line to the second house;
Provided in the second distribution line, when the third switch part is on, cut off the power supply from the second distribution line to the second house, and when the third switch part is off, the power to the second house A fourth switch part enabling supply,
A third power line carrier communication device capable of injecting a high frequency signal and extracting a high frequency signal on both the supply side of the first switch unit and the supply side of the second switch unit;
A power line carrier communication comprising a fourth power line carrier communication device capable of injecting a high frequency signal and extracting a high frequency signal on both the supply side of the third switch part and the supply side of the fourth switch part. system. The first distribution line and the second distribution line have a shield layer,
At least one of the third power line carrier communication device and the fourth power line carrier communication device is
A pair of sixth ferromagnets and seventh ferromagnets respectively disposed on the supply side of the switch part provided on the first distribution line and on the supply side of the switch part provided on the second distribution line;
The sixth and seventh ferromagnets are respectively disposed on the sixth and seventh ferromagnets, and comprise sixth and seventh windings through which high-frequency signals are transmitted,
High-frequency signals are transmitted to both the supply side of the switch unit provided in the first distribution line and the supply side of the switch unit provided in the second distribution line via the sixth winding and the seventh winding. 7. The power line carrier communication system according to claim 6, wherein Between the first house and the first switch part and the second switch part,
A first transformer capable of transforming a voltage applied to the first distribution line and the second distribution line;
Comprising a first low-voltage line capable of supplying the electric power transformed by the first transformer to the first house,
By bypassing the first transformer, comprising a first bypass mechanism that enables communication by a high-frequency signal between the first distribution line and the second distribution line and the first low-voltage line,
Between the second house and the third switch part and the fourth switch part,
A second transformer capable of transforming a voltage applied to the first distribution line and the second distribution line;
A second low-voltage line capable of supplying the power transformed by the second transformer to the second house,
A second bypass mechanism is provided, which bypasses the second transformer and enables communication by a high-frequency signal between the first distribution line and the second distribution line and the second low-voltage line. 6. The power line carrier communication system according to 6 or 7. The first low-voltage line arranged on the demand side of the first transformer and the second low-voltage line arranged on the demand side of the second transformer do not have a shield layer,
The first distribution line and the second distribution line arranged on the supply side of the first transformer and the supply side of the second transformer have a shield layer,
At least one of the first bypass mechanism and the second bypass mechanism is
An eighth ferromagnet and a ninth ferromagnet respectively disposed on the low-voltage line on the demand side of the transformer and the distribution line on the supply side of the transformer;
The eighth and ninth ferromagnets, respectively, comprising an eighth winding and a ninth winding through which a high-frequency signal is transmitted;
9. The power line carrier communication system according to claim 8, wherein a high-frequency signal can be transmitted between a supply side and a demand side of the transformer via the eighth winding and the ninth winding.

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