JP3105875B2 - Remote power supply method and system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data transmission network, and more particularly, to power supply to devices constituting the network.

[0002]

2. Description of the Related Art At present, in an environment where a plurality of personal computers and workstations exist, various devices including these information processing devices are used as nodes, and a LAN (local area network) connecting the nodes to one another is constructed. This is commonly done.

[0003] As a cable for connecting these nodes, an UTP (unshielded twisted-pair) cable is widely used. As a system for supplying power to a node, there has conventionally been a remote power supply system for supplying power from another node via a UTP cable.

[0004] As an example of a conventional remote power supply system,
There is a remote power supply system in which a power supply device is added as a node to a LAN, and a device to receive power supply and a power supply device are connected by a special UTP cable including a pair cable dedicated to power supply. As another example, there is a system in which power is supplied using a pair of cables not used for data transmission among four pairs of cables included in a general UTP cable.

[0005]

In the former example, a power supply device must be added to the LAN as a new device.
In addition, since a special cable must be used for connection to a device to be supplied with power, the cost increases.

On the other hand, in the latter example, there is a problem that the UTP cable does not always include a surplus pair cable. Depending on the device, a UTP cable that only has a pair cable necessary for data communication may be used. In this case, a survey is performed on a pair other than the pair cable provided for data communication, and re-wiring is performed when introducing a remote power supply system. May be required.

The problem to be solved by the present invention is that it is not necessary to add a special device as a node to the LAN, it is not necessary to use a special UTP cable, and it is necessary to take measures such as rewiring when introducing the system. There is no remote power supply method and system.

[0008]

SUMMARY OF THE INVENTION The present invention uses two pairs of cables which are always used in UTP cables, so that even when a remote power supply system is introduced into an existing LAN, special construction or the like is required. , A remote power supply function can be realized.

More specifically, the present invention provides the following means for solving the above-mentioned problems.

According to the present invention, a DC voltage is supplied from one of two devices connected by a first pair cable and a second pair cable which are two pairs of cables to which an AC voltage for data transmission is applied. In the remote power supply method, four power transmission pairs each including one cable constituting a first paired cable and one cable constituting a second paired cable
Define the cable and the magnitude of the DC voltage to be transmitted
A defining step of defining for each transmission pair cable, a feeding step of feeding side of the device a DC voltage is applied to the set of cables,
Receiving a DC voltage from a set of cables on a power receiving side device. The power supply step may include a step of inverting the polarity of the applied DC voltage. The method may further include detecting a short circuit state and an open state of the first and second paired cables.

The present invention further provides a DC voltage from one of two devices connected by a first and a second pair of cables, which are two pairs of cables to which an AC voltage for data transmission is applied. A remote power supply system for supplying, a cable bundle including first and second paired cables;
Four sets of one cable constituting the first pair cable and one cable constituting the second pair cable
For each pair of power transmission cables,
A power supply circuit for applying a separately determined DC voltage and a power transmission
Providing remote power supply system, characterized in that it comprises a receiving circuit from a set of A cable receiving the DC voltage. The power supply circuit may include means for inverting the polarity of the applied DC voltage. Short circuit caused by power transmission pair cable
An abnormality detection circuit for detecting the open state and the open state may be provided.

The remote power supply system of the present invention can also be applied to a cable whose cable bundle is composed of only the first and second paired cables. An example of a typical cable bundle is a UTP (unshielded twisted-pair) cable.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION First Embodiment A remote power supply method according to a first embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows two pairs of cables T and R used for normal data transmission among the cables constituting the UTP cable. Pair cable T consists cable T ₁ and T _2, the AC voltage V _t for the data communication between the T ₁ and T ₂ are applied. Similarly, pair cable R is an AC voltage V _r is applied consists cable R ₁ and R _2. Here, T ₁ , T ₂ and R ₁ ,
R ₂ is the number 3, 6, and 1 of the RJ-45 connector, respectively.
No. 2 corresponds to the cable normally connected to No. 2.

For four cables T ₁ , T ₂ , R ₁ and R ₂ , a set of two cables (T ₁ , T ₂ ), (T ₁ , R ₁ ), (T ₁ , R ₂ ), (T ₂ ,
R _1), can be defined six sets of cables (T _2, R ₂₎ and (R _1, R _2). In the following description, these cable sets are already used for data communication (T ₁ ,
T ₂ ) and four sets (T ₁ , R ₁ ) excluding (R ₁ , R ₂ ),
The cables (T ₁ , R ₂ ), (T ₂ , R ₁ ), and (T ₂ , R ₂ ) are called power transmission pair cables. The present invention realizes remote power supply by applying a DC voltage to a power transmission pair cable.

[0016] As shown in FIG. 1 (a), applies a DC voltages V ₁ between T ₁ -R _1. Similarly, between T _{2 and} R ₂ , V ₂ and T ₁
Between -R ₂ is between V _3, T ₂ -R ₁ applies a DC voltage of V _4. T ₁ -T ₂ and between R ₁ -R Between ₂ actually DC voltage is not applied, an AC voltage for data communication V _t and V _r
Is applied. The correlation of the DC voltage applied to the power transmission pair cable is as shown in FIG.

Assuming that the DC voltage applied on the power supply side is N,
In the simplest embodiment, N is unique and V ₁ = V ₂ = V
₃ = it is an V ₄ = N, but defines a plurality of direct current voltages as N, it is possible to assign them to V ₁ ~V _4.

The DC voltage N of V _{1 to} V ₄ is sensed on the power receiving side through the UTP cable. On the power receiving side, a voltage N-x lower than the applied voltage N by the voltage loss x in the line is observed. That is, the power receiving side can receive the DC power supply of the voltage N−x from the power supply side.

As described above, according to the first embodiment of the present invention, in a LAN environment constituted by 10BASE-T, which is widely used at present, a device connected by using a UTP cable is used. On the other hand, there is an effect that remote power supply can be performed.

2. Second Embodiment A remote power supply system according to a second embodiment of the present invention will be described with reference to the drawings.

2.1 Configuration on the Power Supply Side FIG. 2 shows the line interface portion 20 of the Ethernet which is the power supply side of the remote power supply system of the present invention. The line interface section 20 is a normal Ethernet MAC (Multi
Access Control) termination unit 21 and each transmission line T
₁ -T ₂ , transformer T22 inserted in reception lines R ₁ -R ₂
And 23, a power supply circuit 24 for supplying power on the line, and an abnormality detection circuit 25 for monitoring the power supply state.

A power supply 26 (hereinafter referred to as a local power supply 26) supplied from an accommodation device accommodating the line interface portion 20.
Is first added to the power supply circuit 24. at the same time,
A control signal 27 from the storage device is connected to the power supply circuit 24. The control signal 27 is a signal for performing / stopping the power supply to the power supply circuit 24, inverting the power supply polarity, controlling the power supply voltage, and the like. An abnormality detection circuit 25 is connected to the power supply circuit 24. This circuit is for detecting an abnormality (an abnormality due to a short circuit, disconnection, or the like) in a line to which power is supplied, and sends an alarm 28 to the accommodation device.

The MAC termination 21 and the transformers T22 and T23
Is well known to those skilled in the art, and is not directly related to the present invention.

The power supply circuit 24 receives a local power supply 26 and a control signal 27. When receiving an instruction to supply power to the line by the control signal 27, the power supply circuit 24 starts supplying power to the paired cables T and R. The DC voltage applied at this time is automatically adjusted by the power supply circuit 24 and is always properly corrected.
The applied potential is usually adjusted so as to satisfy the relationship of T> R (that is, the T side has a positive potential with respect to the R side). The control signal 27 changes the applied potential to T <R (that is, the T side becomes the R side). On the other hand, it is also possible to make the potential negative. Changing the relationship between the applied voltages in this manner is called a polarity inversion function. The power supply capacity that can be supplied depends on the type and distance of the UTP cable used, environmental conditions, and the like. Note that T
Because between ₁ between -T ₂ and R ₁ -R ₂ DC voltage is not applied, the data communication is not affected.

An abnormality detection circuit 25 is connected to the power supply circuit 24. The abnormality detection circuit 25 detects an abnormality (an abnormality due to a short circuit, a disconnection, or the like) of a line to which power is supplied, and sends an alarm 28 to the housing device and the power supply circuit 24. For example, if the line is short-circuited, the current value due to the applied voltage becomes abnormally large. The abnormality detection circuit 25 detects such an abnormality and notifies the accommodation device as an alarm 28. When an abnormality is detected in this way, the abnormality detection circuit 25 sends an alarm 28.

2.2 Configuration of Power Receiving Side Referring to FIG. 3, there is shown a line interface portion 30 of the Ethernet which is a power receiving side of the remote power supply system of the present invention. Line interface portion 30, the transformer T3 is inserted MAC terminating unit 31 of the conventional Ethernet, each transmission line T ₁ -T _2, the reception line R ₁ -R ₂
2 and 33, power receiving circuit 3 for extracting power supply voltage from the line
4 and an abnormality detection circuit 35 for monitoring the power receiving state.

The power supplied remotely from the line is first received by the power receiving circuit 34, taken out as power, and used as a power supply 36 (hereinafter, referred to as a remote power supply 36) of the accommodation device. At the same time, a control signal 37 from the housing device is connected to the power receiving circuit 34. The control signal 37 is for performing / stopping power reception, detecting inversion of the electrode receiving property, monitoring the received voltage, and the like for the power receiving circuit 34. Power receiving circuit 3
4 is connected to an abnormality detection circuit 35. Abnormality detection circuit 3
Reference numeral 5 is for detecting an abnormality (an abnormality due to a short circuit, disconnection, or the like) of a line to which power is supplied, and sending an alarm 38 to the accommodation device.

[0028] MAC termination 31 and transformers T32, 33
Is well known to those skilled in the art, and is not directly related to the present invention.

The power supplied remotely by the line is first applied to the power receiving circuit 34. At the same time, a control signal 37 from the housing device is input to the power receiving circuit 34. The control signal 37 is
This is for performing / stopping power reception, detecting reversal of the electrode receiving property, controlling the power receiving voltage, and the like for the power receiving circuit 34.

When receiving an instruction to receive power from the line by the control signal 37, the power receiving circuit 34 extracts power from the paired cables T and R. The DC voltage applied at this time is automatically monitored by the power receiving circuit 34 and is always checked for properness.

[0031] As in FIG. 1, T ₁ -R DC voltages V ₁ between ₁ is applied at a feed side, likewise V ₂ between _{T 2 -R 2, T 1 -R} 2
V ₃ is applied during the period and V ₄ is applied between T _{2 and} R ₁ , and V ₁ =
Assume that V ₂ = V ₃ = V ₄ = N. The power supply capacity that can be supplied depends on the type and distance of the UTP cable used, environmental conditions, and the like, and a voltage drop due to the cable occurs. Assuming that this voltage loss is x, a voltage of Nx is observed on the power receiving side. This voltage Nx is taken out by the power receiving circuit 34 and supplied to the accommodation device as the remote power supply 36.

By the polarity inversion function described above, the applied potential is T> R (that is, the T side is a positive potential with respect to the R side).
And T <R (that is, the T side has a negative potential with respect to the R side). The power receiving circuit 34 has a function of detecting this polarity inversion.

Since no DC voltage is applied between T _{1 and} T _{2 and} between R _{1 and} R _2, there is no effect on actual data communication.

An abnormality detection circuit 35 is connected to the power receiving circuit 34. This circuit detects an abnormality of a line to be supplied with power (an abnormality due to a short circuit, disconnection, or the like) or a decrease in receiving voltage, and sends an alarm 38 to the device. For example, if the line (line) is short-circuited, the applied voltage cannot reach a specified value and an abnormality can be detected. When such an abnormality is detected, the abnormality detection circuit sends an alarm 38.

[0035]

Conventionally, power supply equipment was required for each device connected to both ends of a UTP cable. However, according to the remote power supply method and system of the present invention, a UTP cable widely used in an Ethernet LAN environment is used. The remote power supply using the UTP cable has an effect that power supply equipment can be omitted from a device connected to one end of the UTP cable without using a special UTP cable.

Although the present invention has been described based on the embodiments, the present invention is not limited to these embodiments, and it is understood that changes and improvements can be made within the ordinary knowledge of those skilled in the art. Of course.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of a remote power supply method according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a power supply side of a remote power supply system according to a second embodiment of the present invention.

FIG. 3 is a diagram illustrating a power receiving side of a remote power supply system according to a second embodiment of the present invention.

[Explanation of symbols]

 20, 30 Line interface section 21, 31 MAC termination 22, 23, 32, 33 Transformer 24 Power supply circuit 25, 35 Abnormality detection circuit 26 Local power supply 27, 37 Control signal 28, 38 Alarm 34 Power reception circuit 36 Remote power supply

Claims (8)

(57) [Claims] 1. A remote power supply for supplying a DC voltage from one of two devices connected by a first and a second pair of cables, which are two pairs of cables to which an AC voltage for data transmission is applied. in the method, the one cable constituting the first pair cable, as well as define the four sets of the transmission pair cable consisting of one cable constituting the second pair cable and transmission
A definition step of defining the magnitude of the DC voltage for each power transmission pair cable; a power supply step of applying a DC voltage to the power transmission pair cable; and a power reception side device receiving the DC voltage from the power transmission pair cable. And a power receiving step. 2. The remote power supply method according to claim 1,
The method further comprises the step of inverting the polarity of the DC voltage applied in the power supply step. 3. The remote power supply method according to claim 1, further comprising a step of detecting a short-circuit state and an open state of said first and second paired cables. Remote power supply method. 4. A remote power supply for supplying a DC voltage from one of two devices connected by a first and a second pair of cables, which are two pairs of cables to which an AC voltage for data transmission is applied. In the system, four sets of: a cable bundle including the first and second paired cables; one cable forming the first paired cable; and one cable forming the second paired cable . for the power transmission pair cable, each transmission Peakebu
A remote power supply system, comprising: a power supply circuit that applies a DC voltage individually determined for each power supply; and a power receiving circuit that receives a DC voltage from the power transmission pair cable. 5. The remote power supply system according to claim 4, wherein said power supply circuit includes means for inverting the polarity of the applied DC voltage. 6. The remote power supply system according to claim 4, further comprising :
A remote power supply system comprising an abnormality detection circuit that detects a short circuit state and an open state . 7. The remote power supply system according to claim 4, wherein the cable bundle includes only the first and second paired cables. 8. The remote power supply system according to claim 4, wherein the cable bundle is a UTP (unshi
A remote power supply system characterized by being an elded twisted-pair) cable.