Power-Over-Fiber Output Control for Distance-Based Attenuation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing optical power supply systems face challenges in improving photoelectric conversion efficiency, particularly on the power-sourcing and powered sides, which affects overall optical power supply efficiency.

Innovation Solution

A power-over-fiber system that includes a power sourcing equipment with a semiconductor laser to output feed light, a powered device with a photoelectric conversion element to convert feed light into electric power, and an optical fiber cable for transmitting feed light. The system features a measurer to determine the distance between the power sourcing equipment and the powered device, and a control device that adjusts the output of the feed light to compensate for attenuation based on the measured distance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Length of stationary object

If the transmission distance is increased to extend the power supply range, then the coverage area is improved, but the feed light attenuation increases and photoelectric conversion efficiency deteriorates

Engineering Contradiction:
Improvetransmission distanceVSAvoidfeed light attenuation
Core Design Contradiction:
Length of stationary objectVSLoss of energy

Solution Approach 1:

The system performs preliminary distance measurement using optical time domain reflection (OTDR) before power supply begins. Based on the measured distance, the control device pre-calculates and applies the appropriate attenuation compensation value to the feed light output, ensuring optimal power delivery is established before the powered device operates

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The control device dynamically adjusts the feed light output parameters based on the measured transmission distance. By changing the output power parameter according to the distance-dependent attenuation characteristics, the system compensates for signal loss and maintains efficient photoelectric conversion at the remote end

Inventive Principle:
Principle #35Parameter changes

2Productivity

If the feed light output power is increased to compensate for attenuation, then the power supply efficiency is improved, but the risk of over-powering and device damage increases

Engineering Contradiction:
Improvepower supply efficiencyVSAvoidover-powering risk
Core Design Contradiction:
ProductivityVSObject-affected harmful factors

Solution Approach 1:

The system uses optical time domain reflection (OTDR) to measure the actual transmission distance and provides feedback to the control device. This feedback mechanism enables the control device to calculate the precise attenuation value and adjust the feed light output accordingly, preventing both under-powering and over-powering conditions

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The distance measurement and attenuation compensation are performed before power supply begins. This preliminary action ensures that the feed light output is precisely calibrated to the actual transmission conditions, eliminating the need for excessive power output and preventing over-powering risks

Inventive Principle:
Principle #10Preliminary action

3Use of energy by moving object

If the photoelectric conversion element size is increased to improve conversion efficiency, then the power conversion efficiency is improved, but the device complexity and size increase

Engineering Contradiction:
Improvephotoelectric conversion efficiencyVSAvoidpowered device size
Core Design Contradiction:
Use of energy by moving objectVSDevice complexity

Solution Approach 1:

The system changes the optical input parameters (power, wavelength, pulse duration) based on the measured transmission distance to optimize the energy delivered to the photoelectric conversion element. This allows the use of smaller, more efficient conversion elements while maintaining high conversion efficiency through optimized input conditions

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The system enhances photoelectric conversion efficiency and ensures appropriate power supply by compensating for feed light attenuation, thereby improving overall optical power supply efficiency.

Implementation Method 1

a semiconductor laser that oscillates with electric power to output feed light

Methodology Applied
Scientific EffectElectroluminescence: Electroluminescence

Implementation Method 2

an optical fiber cable that transmits the feed light from the power sourcing equipment to the powered device

Methodology Applied
Scientific EffectTotal internal reflection: Total Internal Reflection

Implementation Method 3

a photoelectric conversion element that converts the feed light into electric power

Methodology Applied
Scientific EffectPhotoelectric conversion: Photoelectric Effect

Data Source

PatentEP4050818B1Optical fiber power supply system
Publication Date: 2025.04.23 KYOCERA CORP
  • EP4050818B1 patent drawingFigure 1
  • EP4050818B1 patent drawingFigure 2
  • EP4050818B1 patent drawingFigure 3

AI summary

To improve the optical power supply efficiency, a power-over-fiber system includes a power sourcing equipment 110 including a semiconductor laser that oscillates with electric power to output feed light, a powered device 310 including a photoelectric conversion element 311 that converts the feed light into electric power, a plurality of optical fiber cables 200A that transmit the feed light, a measurer 150A that measures a distance from the power sourcing equipment to the powered device, and a control device 153A that controls the power sourcing equipment to output the feed light after compensating for an amount of attenuation of the feed light according to a transmission distance on the basis of the distance from the power sourcing equipment to the powered device measured by the measurer.