Optical power supply system, method for restoring the optical power supply system, and optical node device

Abstract

An optical power supply system, a restoration method for the optical power supply system, and an optical node device according to the present invention relate to an optical node device comprising: a branching unit into which is input power supply light including either light of a first light source or light of a second light source, and which outputs light of the first light source from a first terminal and outputs light of the second light source from a second terminal; a photoelectric conversion unit that receives the power supply light and converts the same into electric power; a power storage unit that stores the electric power output from the photoelectric conversion unit; an optical switch having a first port, a second port, a third port, and a fourth port; and a control unit that at least controls the optical switch. The first terminal and the first port are connected, the second terminal and the second port are connected, and the fourth port and the photoelectric conversion unit are connected. The optical switch has: a first connection state in which the first port and the third port are connected and the second port and the fourth port are connected; and a second connection state in which the first port and the fourth port are connected and the second port and the third port are connected.

Description

Technical Field

[0001] The present disclosure relates to an optical power supply system, a method for restoring an optical power supply system, and an optical node device.

Background Art

[0002] As optical fiber networks, particularly access networks connecting telecommunications carriers and optical terminals, spread, optical communication is being used in various devices such as wireless base stations, smart meters, and various sensors. Among these devices, in order to supply power to devices installed in locations without commercial power, optical power supply systems using optical fiber networks have been studied.

[0003] Non-Patent Document 1 discloses a technique related to a wide-area sensor network using an optical fiber power supply type sensor node. According to this technique, steady light is transmitted from a monitoring device composed of a laser light source and a photoreceiver to a wireless sensor node installed at an arbitrary location separated via an optical fiber. Then, in the wireless sensor node, a drive power obtained by photoelectric conversion based on the steady light drives a wireless reception circuit provided in the wireless sensor node and a modulator that converts a wireless signal into an upstream optical signal, and the upstream optical signal is transmitted to the monitoring device. This enables accommodation of a large number of sensors over a wide area.

[0004] According to the technique described in Non-Patent Document 1, when driving a large number of devices with one light source, it is necessary to branch the output from the light source to a plurality of optical fibers and connect an optical fiber for each device. Patent Document 1 discloses a technique in which an optical switch is installed in each device, and a device to be powered is selected by operating the optical switch from each device.

Prior Art Documents

Non-Patent Documents

[0005]

Non-Patent Document 1

[0006] [Patent Document 1] International Publication No. 2022 / 102103 [Overview of the project] [Problems that the invention aims to solve]

[0007] According to the technology described in Patent Document 1, whether to supply optical power to the device or to another device installed downstream of the device is determined by the control unit of the device controlling the optical switch installed in the device. However, if the device loses power due to a malfunction or disturbance such as a lightning strike while supplying optical power to another device downstream, the control unit of the device will not operate and will be unable to control the optical switch. As a result, the device cannot be charged, and it becomes difficult to restore the device.

[0008] Furthermore, if the control unit of the device stops due to external disturbances such as miscontrol or lightning strikes while it is supplying optical power to other devices downstream, the device will lose power through natural discharge, making it difficult to restore its functionality.

[0009] This disclosure has been made in view of the above-mentioned problems. Its purpose is to provide an optical power supply system, a method for restoring an optical power supply system, and an optical node device that can easily restore an optical node device even if a miscontrol or disturbance affecting the power or operation of the optical node device occurs while the optical node device is supplying optical power to other devices downstream of the optical node device. [Means for solving the problem]

[0010] To solve the above-mentioned problems, an optical power supply system, a method for restoring an optical power supply system, and an optical node device according to one aspect of the present disclosure relate to an optical node device comprising: a branching unit that receives power supply light including either light from a first light source or light from a second light source, outputs light from the first light source from a first terminal, and outputs light from the second light source from a second terminal; a photoelectric conversion unit that receives the power supply light and converts it into electricity; a power storage unit that stores the power output from the photoelectric conversion unit; an optical switch having a first port, a second port, a third port, and a fourth port; and a control unit that controls the optical switch. The first terminal and the first port are connected, the second terminal and the second port are connected, and the fourth port is connected. The optical switch has a first connection state in which the first port and the third port, and the second port and the fourth port are connected, and a second connection state in which the first port and the fourth port, and the second port and the third port are connected. [Effects of the Invention]

[0011] According to this disclosure, even if a malfunction or disturbance affecting the power or operation of the device occurs while the device is supplying optical power to other devices downstream, the device can be easily restored. [Brief explanation of the drawing]

[0012] [Figure 1] Figure 1 shows the configuration of the optical power supply system according to the present disclosure. [Figure 2] Figure 2 shows the configuration of an optical power supply system according to a modified embodiment of the present disclosure. [Modes for carrying out the invention]

[0013] Next, embodiments of the present disclosure will be described in detail with reference to the drawings. In the description, identical components are denoted by the same reference numerals, and redundant explanations will be omitted.

[0014] [Configuration of the optical power supply system] Figure 1 shows the configuration of an optical power supply system according to an embodiment of the present disclosure. As shown in Figure 1, the optical power supply system 1 includes a first light source 11, a second light source 12, a light source switching unit 20, an optical fiber FB, and an optical node device 100. The optical power supply system 1 may also include a transmitting unit 30. Furthermore, other devices 200 may be connected downstream of the optical node device 100.

[0015] The first light source 11 and the second light source 12 output light (supply light) for optical power supply to the optical node device 100. The supply light includes at least one of the light from the first light source and the light from the second light source. For example, the first light source 11 and the second light source 12 are beam light sources such as lasers. The wavelength of the light from the first light source 11 may be different from the wavelength of the light from the second light source 12.

[0016] The light source switching unit 20 introduces the power supply light output from the first light source 11 or the second light source 12 into the optical fiber FB. For example, the light source switching unit 20 may be connected to the first light source 11 and the second light source 12, and selectively use either the light from the first light source 11 or the light from the second light source 12 as the power supply light. More specifically, the light source switching unit 20 may be an optical switch.

[0017] The optical power supply system 1 does not necessarily have to include a light source switching unit 20. In this case, the administrator managing the optical power supply system 1 may select either the first light source 11 or the second light source 12 and connect the selected light source to the optical fiber FB.

[0018] The transmitting unit 30 outputs a control signal superimposed on the power supply light at one end of the optical fiber FB. For example, the transmitting unit 30 may be an optical media converter that converts a control signal received from an external device as an electrical signal into an optical signal, and outputs the optical signal superimposed on the power supply light.

[0019] The optical fiber FB transmits power supply light that includes either the light from the first light source 11 or the light from the second light source 12. The optical fiber FB may also transmit power supply light on which control signals are superimposed.

[0020] The optical node device 100 is provided on the other end side of the optical fiber FB, and the optical node device 100 receives the power supply light transmitted through the optical fiber FB. The optical node device 100 may receive the power supply light with a control signal superimposed thereon.

[0021] The optical node device 100 includes a branching unit 110, an optoelectronic conversion unit 120, a power storage unit 130, an optical switch 140, and a control unit 150. The optical node device 100 may include a receiving unit 40.

[0022] The receiving unit 40 receives the control signal superimposed on the power supply light at the other end side of the optical fiber FB. For example, the receiving unit 40 may be an optical media converter that receives a part of the power supply light and converts it into an electrical signal, and outputs the electrical signal as a control signal. For example, the control signal may be transmitted to the control unit 150 described later. The receiving unit 40 may be a photodiode.

[0023] The branching unit 110 receives the power supply light transmitted through the optical fiber FB. Then, the branching unit 110 outputs the light of the first light source 11 included in the power supply light from the first terminal T1 and outputs the light of the second light source 12 from the second terminal T2. For example, when the wavelength of the light of the first light source 11 is different from the wavelength of the light of the second light source 12, the branching unit 110 may branch the light of the first light source 11 and the light of the second light source 12 by wavelength branching. More specifically, the branching unit 110 may be a WDM (Wavelength Division Multiplexing) optical coupler.

[0024] The optoelectronic conversion unit 120 receives the power supply light and converts it into electric power. For example, the optoelectronic conversion unit 120 may be a photodiode.

[0025] The power storage unit 130 stores the electric power output from the optoelectronic conversion unit 120. For example, the power storage unit 130 may be a capacitor, a battery, or the like.

[0026] The optical switch 140 has a first port P1, a second port P2, a third port P3, and a fourth port P4. The optical switch 140 has a first connection state in which the first port P1 and the third port P3, and the second port P2 and the fourth port P4 are connected. The optical switch 140 also has a second connection state in which the first port P1 and the fourth port P4, and the second port P2 and the third port P3 are connected. The optical switch 140 is driven by power supplied from the energy storage unit 130.

[0027] Furthermore, the first port P1 of the optical switch 140 is connected to the first terminal T1 of the branching unit 110, and the second port P2 of the optical switch 140 is connected to the second terminal T2 of the branching unit 110. In addition, the fourth port P4 of the optical switch 140 is connected to the photoelectric conversion unit 120. In addition, the third port P3 of the optical switch 140 may be connected to another device 200.

[0028] The control unit 150 is driven by power supplied from the energy storage unit 130 and controls at least the optical switch 140. The optical switch 140 switches between a first connection state and a second connection state based on a control signal from the control unit 150. Here, the control signal may be a control signal received by the receiving unit 40.

[0029] [Differentiation] Figure 2 shows the configuration of an optical power supply system according to a modified embodiment of the present disclosure. Unlike the optical node device 100 shown in Figure 1, the optical node device 100 shown in Figure 2 further includes a voltage monitoring unit 160 and a power supply control unit 170.

[0030] The voltage monitoring unit 160 monitors the voltage of the energy storage unit 130. The voltage monitoring unit 160 determines whether the voltage of the energy storage unit 130 is above a predetermined threshold, and if it is above the predetermined threshold, it sends a signal to the power control unit 170.

[0031] The power control unit 170 switches the control unit 150 between the ON and OFF states based on a signal from the voltage monitoring unit 160. More specifically, when the power control unit 170 receives a signal from the voltage monitoring unit 160, it restarts the control unit 150. More specifically, the power control unit 170 switches the control unit 150 from the ON state to the OFF state, and then switches the control unit 150 from the OFF state to the ON state.

[0032] [How to restore the optical power supply system] Next, we will explain how to recover from an abnormal state in the optical power supply system 1 shown in Figures 1 and 2.

[0033] The following are examples of situations in which the optical power supply system 1 may be in an abnormal state. For example, the power storage unit 130 of the optical node device 100 may be unable to supply power. Also, the control unit 150 may be in an abnormal state.

[0034] Examples of situations in which the power storage unit 130 of the optical node device 100 may be unable to supply power include cases where power is lost in the power storage unit 130 due to external disturbances such as miscontrol or lightning strikes. Other examples include cases where the power stored in the power storage unit 130 is lost due to natural discharge or other reasons when the optical node device 100 is left unattended for a long period of time. However, the examples of situations in which the power storage unit 130 of the optical node device 100 may be unable to supply power are not limited to those listed above.

[0035] Furthermore, an example of when the control unit 150 is in an abnormal state is when the operation of the control unit 150 stops due to external disturbances such as miscontrol or lightning strikes. Examples of when the control unit 150 is in an abnormal state are not limited to those listed here.

[0036] If the power storage unit 130 of the optical node device 100 is unable to supply power, and the optical switch 140 is in the first connection state, the light from the second light source 12 is first input to the optical fiber FB as the power supply light. Alternatively, the light source switching unit 20 may be switched to input the light from the second light source 12 to the optical fiber FB, or the administrator may connect the second light source 12 to the optical fiber FB to input the light from the second light source 12 to the optical fiber FB. As a result, the light from the second light source 12 reaches the photoelectric conversion unit 120 via the optical fiber FB.

[0037] Subsequently, the photoelectric conversion unit 120 converts the light from the second light source 12 that has arrived into electrical power, and uses the converted electrical power to charge the energy storage unit 130.

[0038] Similarly, if the power storage unit 130 of the optical node device 100 is unable to supply power, and the optical switch 140 is in the second connection state, the light from the first light source 11 is first input to the optical fiber FB as the power supply light. Alternatively, the light source switching unit 20 may be switched to input the light from the first light source 11 to the optical fiber FB, or the administrator may connect the first light source 11 to the optical fiber FB to input the light from the first light source 11 to the optical fiber FB. As a result, the light from the first light source 11 reaches the photoelectric conversion unit 120 via the optical fiber FB.

[0039] Subsequently, the photoelectric conversion unit 120 converts the light from the first light source 11 that has arrived into electrical power, and uses the converted electrical power to charge the energy storage unit 130.

[0040] In this way, the power to the energy storage unit 130 is restored, allowing the energy storage unit 130 to supply power and recover from the abnormal state.

[0041] Furthermore, if the control unit 150 is in an abnormal state and the optical switch 140 is in the first connection state, the light from the second light source 12 is first input to the optical fiber FB as power supply light. As a result, the photoelectric conversion unit 120 converts the light from the second light source 12 that has arrived into power, and charges the energy storage unit 130 with the converted power.

[0042] Similarly, if the control unit 150 is in an abnormal state and the optical switch 140 is in the second connection state, first, the light from the first light source 11 is input to the optical fiber FB as power supply light. As a result, the photoelectric conversion unit 120 converts the light from the first light source 11 that has arrived into power, and charges the energy storage unit 130 with the converted power.

[0043] As the charging of the energy storage unit 130 progresses and the voltage of the energy storage unit 130 exceeds a predetermined threshold, the voltage monitoring unit 160 transmits a signal to the power control unit 170 indicating that the voltage of the energy storage unit 130 has exceeded a predetermined threshold. Subsequently, when the power control unit 170 receives the signal from the voltage monitoring unit 160, it restarts the control unit 150.

[0044] In this way, the abnormal state can be recovered by restarting the control unit 150.

[0045] [Effects of the Embodiment] As described in detail above, the optical power supply system according to this embodiment comprises a first light source, a second light source, an optical fiber for transmitting power supply light including either the light from the first light source or the light from the second light source, and an optical node device to which the power supply light transmitted via the optical fiber is input.

[0046] Herein, the optical node device according to this embodiment includes a branching unit that receives power supply light, outputs light from a first light source from a first terminal, and outputs light from a second light source from a second terminal; a photoelectric conversion unit that receives power supply light and converts it into electricity; a power storage unit that stores the power output from the photoelectric conversion unit; an optical switch having a first port, a second port, a third port, and a fourth port, which is driven by the power supplied from the power storage unit; and a control unit that controls at least the optical switch and is driven by the power supplied from the power storage unit.

[0047] Furthermore, the first terminal is connected to the first port, the second terminal is connected to the second port, and the fourth port is connected to the photoelectric conversion unit. The optical switch has a first connection state in which the first port is connected to the third port and the second port is connected to the fourth port, and a second connection state in which the first port is connected to the fourth port and the second port is connected to the third port.

[0048] This allows for easy recovery of the optical node even if a miscontrol or disturbance affecting the power or operation of the optical node occurs while it is supplying optical power to other devices downstream. In particular, it enables recovery from situations where power is lost in the energy storage unit of the optical node and the energy storage unit is unable to supply power, or when the control unit of the optical node is in an abnormal state.

[0049] Furthermore, in the optical power supply system and optical node device according to this embodiment, the wavelength of the light from the first light source may differ from the wavelength of the light from the second light source, and the branching unit may branch the light from the first light source and the light from the second light source by wavelength branching. This ensures that at least one of the light from the first light source or the light from the second light source is reliably introduced into the photoelectric conversion unit and the energy storage unit is charged. As a result, the optical node device can be restored.

[0050] Furthermore, the optical power supply system and optical node device according to this embodiment may further include a light source switching unit connected to the first and second light sources, which selectively supplies power from either the light of the first or the light of the second light source. This allows at least one of the light from the first or second light source to be introduced into the optical fiber and guided to the optical node device as power supply light. The optical node device can be restored by charging the energy storage unit with the power supply light.

[0051] Furthermore, the optical power supply system and optical node device according to this embodiment may further include a transmitting unit that superimposes a control signal onto the power supply light and outputs it at one end of the optical fiber, and a receiving unit that receives the control signal superimposed on the power supply light at the other end of the optical fiber. The control unit may also control at least an optical switch based on the control signal. This allows a control signal for controlling the optical node device to be transmitted to the optical node device via the optical fiber when the control unit of the optical node device is not in an abnormal state.

[0052] Furthermore, the optical power supply system and optical node device according to this embodiment may further include a voltage monitoring unit that monitors the voltage of the energy storage unit, and a power control unit that switches the control unit between an on state and an off state based on a signal from the voltage monitoring unit. This allows the control unit to be restarted if the control unit of the optical node device is in an abnormal state.

[0053] Furthermore, the recovery method for the optical power supply system according to this embodiment may involve, when the optical switch is in the first connection state and the power storage unit cannot supply power to the control unit, inputting light from the second light source as power supply light into the optical fiber, allowing the light from the second light source to reach the photoelectric conversion unit, and charging the power storage unit with the power converted from the light from the second light source.

[0054] This allows for easy recovery of the optical node device even if a miscontrol or disturbance occurs that affects the power or operation of the optical node device while it is supplying optical power to other devices downstream. In particular, it enables recovery from situations where the power storage unit of the optical node device is lost and unable to supply power.

[0055] Furthermore, the recovery method for the optical power supply system according to this embodiment may involve, when the optical switch is in the first connection state and the control unit is in an abnormal state, inputting light from the second light source as power supply light into the optical fiber, causing the light from the second light source to reach the photoelectric conversion unit, and charging the energy storage unit with the power converted from the light from the second light source. The voltage monitoring unit may then determine whether the voltage has exceeded a predetermined threshold, and if it is determined that the voltage has exceeded the predetermined threshold, the power supply control unit may restart the control unit to recover it from the abnormal state.

[0056] This allows for easy recovery of the optical node device even if a control error or disturbance affecting the power or operation of the optical node device occurs while it is supplying optical power to other devices downstream. In particular, it enables recovery even when the control unit of the optical node device is in an abnormal state.

[0057] While the contents of this disclosure have been described above in accordance with the embodiments, it will be obvious to those skilled in the art that this disclosure is not limited to these descriptions and that various modifications and improvements are possible. The discussions and drawings that constitute part of this disclosure should not be understood as limiting this disclosure. Various alternative embodiments, examples and operational techniques will become apparent to those skilled in the art from this disclosure.

[0058] This disclosure naturally includes various embodiments and other features not described herein. Therefore, the technical scope of this disclosure is determined solely by the inventive features relating to the claims that are reasonable given the above description. [Explanation of Symbols]

[0059] 1. Optical power supply system 11 1st light source 12 Second light source 20 Light source switching unit 30 Transmitter 40 Receiver 100 Optical Node Devices 110 Branching point 120 Photoelectric conversion unit 130 Energy Storage Unit 140 Optical switch 150 Control Unit 160 Voltage Monitoring Unit 170 Power supply control unit FB optical fiber P1 Port 1 P2 2nd Port P3 3rd Port P4 4th Port T1 First terminal T2 Second terminal

Claims

1. First light source and The second light source and An optical fiber that transmits power supply light including either the light from the first light source or the light from the second light source, An optical node device to which the power supply light transmitted via the optical fiber is input, A light-power supply system comprising, The optical node device is, A branching section that receives the aforementioned power supply light, outputs light from the first light source from the first terminal, and outputs light from the second light source from the second terminal, A photoelectric conversion unit that receives the aforementioned power supply light and converts it into electricity, A power storage unit that stores the power output from the photoelectric conversion unit, An optical switch having a first port, a second port, a third port, and a fourth port, which is driven by power supplied from the energy storage unit, A control unit that controls at least the optical switch and is driven by power supplied from the energy storage unit, Equipped with, The first terminal and the first port are connected, The second terminal and the second port are connected, The fourth port and the photoelectric conversion unit are connected, The aforementioned optical switch is A first connection state in which the first port and the third port, and the second port and the fourth port are connected, A second connection state in which the first port and the fourth port, and the second port and the third port are connected, A light-power supply system having the following features.

2. The wavelength of light from the first light source is different from the wavelength of light from the second light source. The optical power supply system according to claim 1, wherein the branching section branches the light from the first light source and the light from the second light source by wavelength branching.

3. The optical power supply system according to claim 1, further comprising a light source switching unit connected to the first light source and the second light source, which selectively uses either the light from the first light source or the light from the second light source as the power supply light.

4. A transmitting unit that superimposes a control signal onto the power supply light and outputs it at one end of the optical fiber, The other end of the optical fiber includes a receiving unit that receives the control signal superimposed on the power supply light, Furthermore, The optical power supply system according to claim 1, wherein the control unit controls at least the optical switch based on the control signal.

5. A voltage monitoring unit that monitors the voltage of the aforementioned energy storage unit, A power control unit that switches the on state and off state of the control unit based on a signal from the voltage monitoring unit, The optical power supply system according to claim 1, further comprising the following:

6. In the optical power supply system according to any one of claims 1 to 5, when the optical switch is in the first connection state and the power storage unit is unable to supply power to the control unit, The light from the second light source is input to the optical fiber as the power supply light, and the light from the second light source reaches the photoelectric conversion unit. A method for restoring an optical power supply system, comprising charging the power storage unit with electricity converted from the light of the second light source.

7. In the optical power supply system according to claim 5, when the optical switch is in the first connection state and the control unit is in an abnormal state, The light from the second light source is input to the optical fiber as the power supply light, and the light from the second light source reaches the photoelectric conversion unit. The power stored in the energy storage unit is charged by the power obtained by converting the light from the second light source. The voltage monitoring unit determines whether the voltage has reached a predetermined threshold or higher. A method for restoring an optical power supply system, wherein, when it is determined that the voltage has exceeded a predetermined threshold, the power supply control unit restarts the control unit to restore it from the abnormal state.

8. An optical node device to which power supply light including either the light from a first light source or the light from a second light source is input, A branching section that receives the aforementioned power supply light, outputs light from the first light source from the first terminal, and outputs light from the second light source from the second terminal, A photoelectric conversion unit that receives the aforementioned power supply light and converts it into electricity, A power storage unit that stores the power output from the photoelectric conversion unit, An optical switch having a first port, a second port, a third port, and a fourth port, which is driven by power supplied from the energy storage unit, A control unit that controls at least the optical switch and is driven by power supplied from the energy storage unit, Equipped with, The first terminal and the first port are connected, The second terminal and the second port are connected, The fourth port and the photoelectric conversion unit are connected, The aforementioned optical switch is A first connection state in which the first port and the third port, and the second port and the fourth port are connected, A second connection state in which the first port and the fourth port, and the second port and the third port are connected, Having An optical node device characterized by the following.

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