JP6889227B2 - Optical power supply system power receiving device and power supply device and optical power supply system - Google Patents

Description

The present disclosure relates to optical power supply.

Recently, an optical power supply system that converts electric power into light (called feed light) and transmits it, converts the feed light into electric energy, and uses it as electric power has been studied.
Patent Document 1 describes an optical transmitter that transmits signal light modulated by an electric signal and feed light for supplying power, a core that transmits the signal light, and a core formed around the core. An optical fiber having a first clad having a small refractive index and transmitting the feeding light and a second clad formed around the first clad and having a smaller refractive index than the first clad, and a first clad of the optical fiber are used for transmission. Described is an optical communication device including an optical receiver that operates with the converted power of the fed light and converts the signal light transmitted by the core of the optical fiber into the electric signal.

Japanese Unexamined Patent Publication No. 2010-135989

In optical power supply, it is ideal that all the power sent from the power supply side is consumed on the power receiving side. However, since the load is not constant but fluctuates, it sends power that exceeds the power consumption of the load. In that case, there is too much power on the power receiving side, which is not efficient.

One aspect of the present disclosure is an optical fiber including a power feeding device including a semiconductor laser that oscillates a laser with electric power and outputs power feeding light, and a power receiving device including a photoelectric conversion element that converts the feeding light by the power feeding device into electric power. It ’s a power supply system,
The power receiving device includes a photoelectric conversion element that converts the power feeding light from the power feeding device into electric power, and outputs a part of the feeding light from the feeding device input to the photoelectric conversion element as feedback feeding light to the feeding side. A branch optical device for monitoring and a control device for monitoring the amount of power supplied to the load of the power converted by the photoelectric conversion element and controlling the amount of feedback by the branch optical device for feedback according to the amount of power supplied.
The power feeding device includes a semiconductor laser that oscillates with a laser by electric power and outputs the feeding light to the power receiving device, and the feedback feeding light from the power receiving device is associated with the feeding light output by the semiconductor laser and output. And a control device that controls the output of the semiconductor laser so that the amount of energy output by the feedback association optical device is constant.

According to the optical power supply system of one aspect of the present disclosure, it is possible to efficiently operate the optical power supply in which the surplus power on the power receiving side is suppressed even if the load fluctuates.

It is a block diagram of the optical fiber power supply system which concerns on 1st Embodiment of this disclosure. It is a block diagram of the optical fiber power supply system which concerns on 2nd Embodiment of this disclosure. It is a block diagram of the optical fiber power supply system which concerns on 2nd Embodiment of this disclosure, and is the figure which showed the optical connector and the like. It is a block diagram of the optical fiber power supply system which concerns on another Embodiment of this disclosure. It is a block diagram of the optical fiber feeding system which has the function of feedback feeding light. It is a graph which shows the time change of the power supply and demand.

An embodiment of the present disclosure will be described below with reference to the drawings.

(1) System overview [First embodiment]
As shown in FIG. 1, the optical fiber power supply (PoF: Power over Fiber) system 1A of the present embodiment includes a power supply device (PSE: Power Sourcing Equipment) 110, an optical fiber cable 200A, and a power receiving device (PD: Powered Device) 310. Be prepared.
The power feeding device in the present disclosure is a device that converts electric power into light energy and supplies it, and a power receiving device is a device that receives the supply of light energy and converts the light energy into electric power.
The power feeding device 110 includes a power feeding semiconductor laser 111.
The optical fiber cable 200A includes an optical fiber 250A that forms a transmission line for feeding light.
The power receiving device 310 includes a photoelectric conversion element 311.

The power feeding device 110 is connected to a power source, and a power feeding semiconductor laser 111 or the like is electrically driven.
The power feeding semiconductor laser 111 oscillates with the electric power from the power source and outputs the power feeding light 112.

In the optical fiber cable 200A, one end 201A can be connected to the power feeding device 110, and the other end 202A can be connected to the power receiving device 310 to transmit the feeding light 112.
The power feeding light 112 from the power feeding device 110 is input to one end 201A of the optical fiber cable 200A, the feeding light 112 propagates in the optical fiber 250A, and is output from the other end 202A to the power receiving device 310.

The photoelectric conversion element 311 converts the feeding light 112 transmitted through the optical fiber cable 200A into electric power. The electric power converted by the photoelectric conversion element 311 is used as the driving power required in the power receiving device 310. Further, the power receiving device 310 can output the electric power converted by the photoelectric conversion element 311 for an external device.

The semiconductor material constituting the semiconductor region that exerts the light-electric conversion effect of the power feeding semiconductor laser 111 and the photoelectric conversion element 311 is a semiconductor having a short wavelength laser wavelength of 500 nm or less.
Since a semiconductor having a short wavelength laser wavelength has a large band gap and high photoelectric conversion efficiency, the photoelectric conversion efficiency on the power generation side and the power receiving side of optical power supply is improved, and the optical power supply efficiency is improved.
For that purpose, as the semiconductor material, for example, a semiconductor material of a laser medium having a laser wavelength (fundamental wave) of 200 to 500 nm, such as diamond, gallium oxide, aluminum nitride, and GaN, may be used.
Further, as the semiconductor material, a semiconductor having a band gap of 2.4 eV or more is applied.
For example, a semiconductor material of a laser medium having a bandgap of 2.4 to 6.2 eV, such as diamond, gallium oxide, aluminum nitride, and GaN, may be used.
The longer the wavelength of the laser light, the better the transmission efficiency, and the shorter the wavelength, the better the photoelectric conversion efficiency. Therefore, in the case of long-distance transmission, a semiconductor material of a laser medium having a laser wavelength (fundamental wave) larger than 500 nm may be used. When the photoelectric conversion efficiency is prioritized, a semiconductor material of a laser medium having a laser wavelength (fundamental wave) smaller than 200 nm may be used.
These semiconductor materials may be applied to either one of the power feeding semiconductor laser 111 and the photoelectric conversion element 311. The photoelectric conversion efficiency on the power feeding side or the power receiving side is improved, and the optical power feeding efficiency is improved.

[Second Embodiment]
As shown in FIG. 2, the optical fiber power supply (PoF: Power over Fiber) system 1 of the present embodiment includes a power supply system via an optical fiber and an optical communication system, and is a power supply device (PSE: Power Sourcing Equipment) 110. A first data communication device 100 including the above, an optical fiber cable 200, and a second data communication device 300 including a power receiving device (PD) 310 are provided.
The power feeding device 110 includes a power feeding semiconductor laser 111. The first data communication device 100 includes a power supply device 110, a transmission unit 120 that performs data communication, and a reception unit 130. The first data communication device 100 corresponds to a data terminal device (DTE (Date Terminal Equipment)), a repeater (Repeater), and the like. The transmitter 120 includes a signal semiconductor laser 121 and a modulator 122. The receiving unit 130 includes a signal photodiode 131.

The optical fiber cable 200 includes an optical fiber 250 having a core 210 forming a signal light transmission path and a clad 220 arranged on the outer periphery of the core 210 and forming a feeding light transmission path.

The power receiving device 310 includes a photoelectric conversion element 311. The second data communication device 300 includes a power receiving device 310, a transmitting unit 320, a receiving unit 330, and a data processing unit 340. The second data communication device 300 is a power end station.
Etc. The transmitter 320 includes a signal semiconductor laser 321 and a modulator 322. The receiving unit 330 includes a signal photodiode 331. The data processing unit 340 is a unit that processes a received signal. The second data communication device 300 is a node in the communication network. Alternatively, the second data communication device 300 may be a node that communicates with another node.

The first data communication device 100 is connected to a power source, and a power feeding semiconductor laser 111, a signal semiconductor laser 121, a modulator 122, a signal photodiode 131, and the like are electrically driven. The first data communication device 100 is a node in the communication network. Alternatively, the first data communication device 100 may be a node that communicates with another node.
The power feeding semiconductor laser 111 oscillates with the electric power from the power source and outputs the power feeding light 112.

The photoelectric conversion element 311 converts the feeding light 112 transmitted through the optical fiber cable 200 into electric power. The electric power converted by the photoelectric conversion element 311 is the driving power of the transmitting unit 320, the receiving unit 330, and the data processing unit 340, and other driving power required in the second data communication device 300. Further, the second data communication device 300 may be capable of outputting the electric power converted by the photoelectric conversion element 311 for an external device.

On the other hand, the modulator 122 of the transmitting unit 120 modulates the laser light 123 from the signal semiconductor laser 121 based on the transmission data 124 and outputs it as the signal light 125.
The signal photodiode 331 of the receiving unit 330 demodulates the signal light 125 transmitted through the optical fiber cable 200 into an electric signal and outputs it to the data processing unit 340. The data processing unit 340 transmits the data obtained by the electric signal to the node, while receiving the data from the node and outputting the data as the transmission data 324 to the modulator 322.
The modulator 322 of the transmitting unit 320 modulates the laser light 323 from the signal semiconductor laser 321 based on the transmission data 324 and outputs it as the signal light 325.
The signal photodiode 131 of the receiving unit 130 demodulates the signal light 325 transmitted through the optical fiber cable 200 into an electric signal and outputs it. The data by the electric signal is transmitted to the node, while the data from the node is referred to as transmission data 124.

The feed light 112 and the signal light 125 from the first data communication device 100 are input to one end 201 of the optical fiber cable 200, the feed light 112 propagates through the clad 220, the signal light 125 propagates through the core 210, and the other end. It is output from 202 to the second data communication device 300.
The signal light 325 from the second data communication device 300 is input to the other end 202 of the optical fiber cable 200, propagates through the core 210, and is output from one end 201 to the first data communication device 100.

As shown in FIG. 3, the first data communication device 100 is provided with an optical input / output unit 140 and an optical connector 141 attached to the optical input / output unit 140. Further, the second data communication device 300 is provided with an optical input / output unit 350 and an optical connector 351 attached to the optical input / output unit 350. An optical connector 230 provided at one end 201 of the optical fiber cable 200 connects to the optical connector 141. An optical connector 240 provided at the other end 202 of the optical fiber cable 200 connects to the optical connector 351. The optical input / output unit 140 guides the feeding light 112 to the clad 220, guides the signal light 125 to the core 210, and guides the signal light 325 to the receiving unit 130. The optical input / output unit 350 guides the feeding light 112 to the power receiving device 310, guides the signal light 125 to the receiving unit 330, and guides the signal light 325 to the core 210.
As described above, the optical fiber cable 200 has one end 201 connectable to the first data communication device 100 and the other end 202 connectable to the second data communication device 300 to transmit the feeding light 112. Further, in the present embodiment, the optical fiber cable 200 transmits the signal lights 125 and 325 in both directions.

As the semiconductor material constituting the semiconductor region that exerts the light-electricity conversion effect of the power feeding semiconductor laser 111 and the photoelectric conversion element 311, the same materials as those in the first embodiment are applied, and high light power feeding efficiency is realized. ..

As in the optical fiber cable 200B of the optical fiber feeding system 1B shown in FIG. 4, the optical fiber 260 for transmitting signal light and the optical fiber 270 for transmitting the feeding light may be provided separately. The optical fiber cable 200B may also be composed of a plurality of cables.

(2) Control of Feedback Feeding Light Next, control of the feedback feeding light will be described with reference to FIGS. 5 and 6 in addition to FIGS. 1 to 4.

FIG. 5 shows the configuration of the optical fiber feeding system 1A1 having the function of feedback feeding light.
The optical fiber power feeding system 1A1 further has the following configurations in the power receiving device 310 and the power feeding device 110 with respect to the optical fiber power feeding system 1A (configuration shown by FIG. 1) described as the first embodiment.
The power receiving device 310 includes a dimming mirror 311F and a control device 312 as a feedback branch optical device.
The dimming mirror 311F outputs a part of the feeding light 112 from the feeding device 110 input to the photoelectric conversion element 311 as the feedback feeding light 112F to the feeding side. The dimming mirror 311F is an electronic device that can electrically switch between a mirror state and a transparent state. The adjustment of the amount of light of the feedback feed light 112F is not only to variably control the ratio of reflectance and transmittance, but also to variably control the duty ratio by periodically executing the period of reflection and the period of transmission. May be good. Instead of the dimming mirror 311F, a mechanism for mechanically switching between reflection and transmission may be applied.
The control device 312 monitors the power supply amount (Q1) of the electric power (Q) converted by the photoelectric conversion element 311 to the load 20, and the feedback amount by the dimming mirror 311F according to the power supply amount (Q1), that is, feedback. The amount of light (P1) of the feed light 112F is controlled.

The power feeding device 110 includes a combiner 111F and a control device 114 as feedback meeting optical devices. The combiner 111F includes an opening in which the feeding light 112G from the feeding semiconductor laser 111 is incident, an opening in which the feedback feeding light 112F is incident, and an opening in which these are merged and the feeding light 112 is emitted. That is, the feedback feeding light 112F from the power receiving device 310 is associated with the feeding light 112G output by the semiconductor laser 111 and output.
The control device 114 controls the output of the semiconductor laser 111 so that the amount of energy output by the combiner 111F is constant (P). Therefore, the output (P) of the semiconductor laser 111 is detected.

Here, the power equivalent of the feed light 112 is P, the power equivalent of the feedback feed light 112F is P1, the power converted by the photoelectric conversion element 311 is Q, and the power supply to the load 20 is Q1. The electric power equivalent amount P of the feeding light 112 is constant, and the time change of P, Q, etc. is shown in the graph as shown in FIG.
On the other hand, the amount of power supply Q1 to the load 20 varies depending on the operating condition, for example, as shown in FIG. 6A.
FIG. 6A shows a case where 110% power Q is prepared with the maximum value of the load 20 as 100%. As a result, the load 20 fluctuates below the maximum value, so that the power is not insufficient and the system can be prevented from going down.
However, the surplus power R1 is wasted and is not efficient.

In the control device 312, the amount of feedback by the dimming mirror 311F, that is, the amount equivalent to the power of the feedback feeding light 112F, so that the power Q converted by the photoelectric conversion element 311 converges to the target value exceeding the load 20 at a predetermined ratio. Control P1.
As a result, a part of the surplus power R1 is sent to the power feeding side as the feedback power feeding light 112F before the power conversion.
The feedback feeding light 112F is input to the combiner 111F and becomes a part of the feeding light 112.
The feeding light 112 corresponds to the sum of the feedback feeding light 112F and the feeding light 112G output by the semiconductor laser 111.

The predetermined ratio is such that the lower limit is 0% and the upper limit is the ratio at which the power Q exceeds the maximum value of the load 20. In the case of this example, the ratio of the electric power Q exceeding the maximum value of the load 20 is 10%, so it is set in the range of 0 to 10%. For example, the target value is set to be 10% higher than the load 20. In this case, it will be as shown in FIG. 6 (b).
When the power supply amount Q1 to the load 20 is the maximum value of 100%, the feedback power supply light 112F (P1) is zero and no feedback is performed. On the other hand, as the power supply amount Q1 to the load 20 becomes lower than the maximum value, the feedback power supply light 112F (P1) is increased to keep the surplus power R2 small.
As usual, the power equivalent amount P of the power supply light 112 output by the power supply device 110 is constant, but the portion that cannot be consumed by the load 20 is fed back as the feedback power supply light 112F before the power conversion, so the power supply 10 covers the power. The new power generated is equivalent to P-P1, and even if the load 20 fluctuates, the surplus power R2 on the power receiving side is suppressed, and efficient optical power supply operation becomes possible.
In the above description, the loss due to the transmission efficiency and the like not being 100% is ignored. Since the feedback is performed before the power conversion, the feedback can be performed without loss due to the photoelectric conversion, which is efficient.

The load 20 is an external load (power output for an external device) in addition to the drive power required in the power receiving device 310.
The optical fiber feeding system 1A1 shown in FIG. 5 has been described based on the first embodiment, but is based on the optical fiber feeding systems 1 and 1B (configuration shown in FIG. 2-4) described as the second embodiment. Similarly, by additionally providing a configuration (111F, 311F, 312) for realizing the function of feedback feeding, the configuration may be implemented including the optical communication system.
In this case, the power Q converted by the photoelectric conversion element 311 provided in the power receiving device 310 is also used as the driving power of the transmitting unit 320 and the receiving unit 330 provided in the second data communication device 300.

Although the embodiments of the present disclosure have been described above, this embodiment is shown as an example, and can be implemented in various other embodiments, and components are omitted as long as the gist of the invention is not deviated. , Can be replaced or changed.

1A1 Optical fiber power supply system (optical power supply system)
1A Optical fiber power supply system (optical power supply system)
1 Optical fiber power supply system (optical power supply system)
1B optical fiber power supply system (optical power supply system)
100 First data communication device 110 Power supply device 111 Power supply semiconductor laser 111F combiner (feedback association optical device)
112 Feeding light 112F Feedback feeding light 114 Controller 120 Transmitter 125 Signal light 130 Receiver 140 Optical input / output 141 Optical connector 200A Optical fiber cable 200 Optical fiber cable 200B Optical fiber cable 210 Core 220 Clad 250A Optical fiber 250 Optical fiber 260 Optical fiber 270 Optical fiber 300 2 Data communication device 310 Power receiving device 311 Photoelectric conversion element 311F Dimming mirror (branch optical device for feedback)
312 Control device 320 Transmitter 325 Signal light 330 Receiver 350 Optical input / output 351 Optical connector

Claims (9)

A power receiving device including a photoelectric conversion element that converts the power feeding light from the power feeding device into electric power.
A feedback branching optical device that outputs a part of the feeding light from the feeding device input to the photoelectric conversion element as feedback feeding light to the feeding side.
A power receiving device of an optical power supply system including a control device that monitors the amount of power supplied to the load of electric power converted by the photoelectric conversion element and controls the amount of feedback by the branch optical device for feedback according to the amount of power supplied. The optical power supply according to claim 1, wherein the control device controls the amount of feedback by the feedback branch optical device so that the power converted by the photoelectric conversion element converges to a target value exceeding the load at a predetermined ratio. Power receiving device of the system. The power receiving device of the optical power supply system according to claim 1 or 2, wherein the semiconductor material constituting the semiconductor region exhibiting the light-electricity conversion effect of the photoelectric conversion element is a laser medium having a laser wavelength of 500 nm or less. A power supply device that includes a semiconductor laser that oscillates a laser with electric power and outputs the power supply light to the power receiving device.
An association optical device for feedback that associates the feedback feeding light from the power receiving device with the feeding light output by the semiconductor laser and outputs the light.
A power supply device for an optical power supply system including a control device for controlling the output of the semiconductor laser so that the amount of energy output by the feedback association optical device is constant. The power supply device for an optical power supply system according to claim 4, wherein the semiconductor material constituting the semiconductor region that exhibits the light-electricity conversion effect of the semiconductor laser is a laser medium having a laser wavelength of 500 nm or less. An optical fiber power feeding system including a power feeding device including a semiconductor laser that oscillates a laser with electric power and outputs power feeding light, and a power receiving device including a photoelectric conversion element that converts the power feeding light by the power feeding device into electric power.
An optical power supply system including the power receiving device according to any one of claims 1 to 3 as the power receiving device, and the power feeding device according to claim 4 or 5 as the power receiving device. A first data communication device including the power feeding device and a second data communication device that optically communicates with the first data communication device and includes the power receiving device are provided.
The optical power supply system according to claim 6, wherein the electric power converted by the photoelectric conversion element is used as a driving power for a transmitting unit and a receiving unit provided in the second data communication device. The optical power supply system according to claim 7, further comprising an optical fiber cable having one end connectable to the power supply device and the other end connectable to the power receiving device to transmit the power supply light. The seventh aspect of claim 7, wherein one end is connectable to the first data communication device, the other end is connectable to the second data communication device, and the optical fiber cable for transmitting the feeding light and the signal light is provided. Optical power supply system.

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