O que é medição de temperatura por fibra óptica? Why use fiber optic temperature measurement system-INNO

Visão geral da medição de temperatura em fibra óptica
1、 O que é medição de temperatura de fibra óptica
A medição de temperatura por fibra óptica é uma tecnologia que utiliza fibras ópticas como elementos sensores para medição de temperatura. Fibra óptica, também conhecida como fibra óptica, é um material de guia de onda dielétrico cilíndrico comumente usado. A essência da tecnologia de detecção de fibra óptica é detectar alvos usando a luz como portadora medida através da comunicação de fibra óptica..

Medição de temperatura de fibra óptica a tecnologia tem vários tipos. A medição de temperatura baseada em pontos é a implantação de uma única sonda de temperatura em certas áreas-chave do sistema para medição.
1. Sensor de temperatura por fibra óptica fluorescente tecnologia é uma técnica que envolve o revestimento de uma substância fluorescente na extremidade de um cabo de fibra óptica. By measuring the decay time of fluorescence energy and utilizing the temperature correlation of the intrinsic afterglow time of the fluorescent substance, the temperature value of the measured point can be obtained. It is suitable for a temperature range of -50-200 ℃ and has an accuracy of about ± 1 ℃. It is mainly used for temperature measurement inside electrical equipment and has the characteristics of small size, fácil integração, desempenho confiável, resistência à interferência eletromagnética, bom desempenho de isolamento, instalação conveniente, e rede flexível.

2. Gallium arsenide fiber temperature measurement technology embeds gallium arsenide crystal material into the far end of the fiber as a temperature probe, injects incident light into the near end device of the fiber, and obtains the temperature parameters at the probe by analyzing the spectrum of the reflected light. Its advantage is that the probe temperature is obtained through absolute spectral measurement, without involving on-site calibration. The probe has good universality, and the sensing distance can exceed 500m. The light source life and online detection long-term stability exceed 30 anos, but the cost is high.

3. Fiber Bragg Grating Measurement
The single point temperature measurement is connected in series along the propagation direction of the optical fiber to form a measurement method that covers multi-point temperature detection. Por exemplo, in a temperature measurement system with multiple fiber Bragg gratings connected in series, several Bragg fiber Bragg gratings with different center wavelengths are formed by exposure and etching through ultraviolet radiation along the longitudinal direction of the optical fiber. When the ambient temperature of the fiber Bragg grating changes, the wavelength of the grating reflection signal also changes. This system has a small probe volume, an appropriate bending of the optical path, resistance to electromagnetic radiation, and is easy to telemetry. No entanto, the mechanical strength of the fiber Bragg grating is low, and it is easily damaged in complex working conditions. The sensitivity of wavelength demodulation is also a problem. The wavelength drift of reflected light caused by a temperature rise of tens of degrees does not exceed 1nm. Fully distributed measurement refers to the use of optical fibers as both a channel for transmitting optical signals and a temperature sensitive material for conducting temperature changes. By deploying a monitoring device and a sensing fiber, o custo de monitoramento por unidade de comprimento de fibra pode ser reduzido à medida que a distância de detecção aumenta. É uma solução de medição de temperatura de engenharia altamente promissora.

2、 Por que usar medição de temperatura por fibra óptica

（1） Vantagens em ambientes especiais

Interferência anti-eletromagnética
Em alguns ambientes com forte interferência eletromagnética, como em torno de equipamentos de alta tensão em sistemas de energia, perto de grandes motores, ou em locais com equipamentos eletrônicos densos, sensores de temperatura tradicionais baseados em medições de sinais elétricos (como termopares, termistores, etc.) será afetado por interferência eletromagnética, resultando em medições imprecisas ou mesmo incapacidade de funcionar corretamente. A própria fibra óptica é um meio óptico, e as ondas de luz não geram interferência eletromagnética, nem têm medo de interferência eletromagnética. Portanto, fiber optic temperature measurement technology can accurately measure temperature in such strong electromagnetic interference environments, ensuring the reliability and stability of measurement results.
Segurança intrínseca
In flammable and explosive environments, such as oil and gas storage sites in the petrochemical industry and underground coal mines, traditional electrical temperature sensors may generate electrical sparks due to their working principle involving electrical signals, which can cause serious safety accidents such as explosions or fires. Fiber optic is made of insulating materials such as glass or plastic, which are not charged and do not generate electrical sparks during the measurement process. Portanto, fiber optic temperature measurement technology has inherent safety characteristics and can safely measure temperature in these hazardous environments, effectively ensuring the safety of personnel and equipment.
Resistência à corrosão
In some harsh chemical environments, such as chemical production workshops and equipment monitoring in marine environments, the air may contain corrosive gases or liquids, which can corrode traditional metal temperature sensors and affect their service life and measurement accuracy. Fiber optic materials have good corrosion resistance and can work stably in such harsh chemical environments for a long time, ensuring the accuracy and continuity of temperature measurement.

（2） Advantages in measuring characteristics
Alta precisão e alta sensibilidade
Fiber optic temperature measurement technology can achieve high-precision temperature measurement and meet the requirements for temperature measurement accuracy in various complex environments. Por exemplo, in scientific research experiments that are highly sensitive to temperature changes, or in temperature monitoring of electronic chips, even small temperature changes can have a significant impact on experimental results or equipment performance. Fiber optic temperature measurement technology can accurately capture these subtle temperature changes. Its high sensitivity also enables it to quickly respond to temperature changes and provide timely feedback on temperature information, which is crucial in some application scenarios that require high temperature response speed, such as temperature monitoring in certain chemical reaction processes.
Long distance monitoring and multi-point measurement

Fiber optic can achieve continuous temperature monitoring for tens or even hundreds of kilometers, and through a fibra óptica distribuída sistema de medição de temperatura, temperature monitoring at multiple points can also be achieved simultaneously. This characteristic is of great significance in some large-scale infrastructure construction and industrial production processes. Por exemplo, in long-distance oil pipeline monitoring, optical fibers can be laid along the pipeline to monitor the temperature of multiple points throughout the pipeline at once, and timely detect temperature anomalies caused by leaks, bloqueios, or external environmental influences in the pipeline; In temperature management of large buildings, optical fibers can also be used to monitor temperature at different locations inside the building, achieving efficient energy management and equipment maintenance.

（3） Other advantages

Can be linked with other systems
The fiber optic temperature measurement system can be linked with fire protection, sistemas de alarme, etc.. When an abnormal temperature rise is detected, the alarm system can be triggered in a timely manner to notify relevant personnel to take measures. Ao mesmo tempo, temperature information can also be provided to the fire protection system for early warning and prevention before a fire occurs. Por exemplo, in densely populated and cargo concentrated places such as large shopping malls and warehouses, the linkage between fiber optic temperature measurement and fire alarm systems can effectively improve fire safety levels and reduce losses from fire accidents.

Convenient data transmission and analysis
Fiber optic can not only serve as a temperature sensor, but also as a medium for temperature measurement and transmission, enabling remote data transmission and facilitating users to remotely view and manipulate measurement results. And it can analyze the collected temperature data for easy troubleshooting. In some remote monitoring or large-scale device monitoring networks, the convenience of data transmission and analysis can greatly improve management efficiency, reduzir custos de manutenção, and timely detect and handle potential problems.