Optical fiber temperature sensing system based on gallium arsenide material

Abstract

The invention discloses an optical fiber temperature sensing system based on a gallium arsenide material, and the system comprises a temperature probe based on a gallium arsenide sensing wafer, an optical fiber optical path system which is used for providing temperature information through the change of a reflection spectrum, and is responsible for the transmission of incident light of a light source and reflected light of a gallium arsenide crystal; the photoelectric detection device is used for collecting a reflection spectrum of the gallium arsenide crystal, performing photoelectric conversion and transmitting the reflection spectrum to the main control unit; the data acquisition and processing system is used for acquiring and processing spectral data and demodulating temperature information through a specific algorithm, the reflection spectrum of the gallium arsenide material has a clear relation with temperature change, and high-precision temperature measurement can be realized through an accurate wavelength-temperature algorithm; according to the system, wavelength information can be accurately extracted from spectral data, temperature calculation is carried out, and an accurate temperature value is provided; as the gallium arsenide material shows better optical characteristics in a wide temperature range, the reflection spectrum of the gallium arsenide material has high stability to temperature change.

Description

Technical Field

[0001] The present invention relates to the technical field of temperature sensing systems, and in particular to an optical fiber temperature sensing system based on gallium arsenide materials. Background Art

[0002] For high-voltage oil-immersed transformers and generators above 110kV, as well as large generators that operate in high-voltage, high-current, and strong magnetic field environments for a long time, the aging of the insulation materials directly determines the service life of the transformer, and the winding "hot spot" temperature plays a decisive role in the aging of the insulation materials. Therefore, real-time online monitoring of the hot spot temperature of transformer and generator windings is crucial. Currently, many power companies have adopted temperature sensors, infrared imaging technology, and other monitoring methods to monitor the hot spot temperature of transformer and generator windings in real time. However, the existing temperature sensing system cannot achieve high-precision temperature measurement, cannot accurately calculate the temperature, and the temperature value accuracy is not high. Summary of the Invention

[0003] The object of the present invention is to provide a fiber optic temperature sensing system based on gallium arsenide material to solve the problems raised in the above background technology.

[0004] To achieve the above objectives, the present invention provides the following technical solution: an optical fiber temperature sensing system based on gallium arsenide material, comprising:

[0005] GaAs sensor wafer-based temperature probes provide temperature information through changes in the reflected light spectrum.

[0006] Fiber optic optical system, responsible for the transmission of incident light from the light source and reflected light from the gallium arsenide crystal;

[0007] A photoelectric detection device is used to collect the reflection spectrum of the gallium arsenide crystal, perform photoelectric conversion, and transmit it to the main control unit;

[0008] The main control unit is responsible for light source control, spectrum information demodulation and temperature information output;

[0009] Data acquisition and processing system, which collects and processes spectral data and demodulates temperature information through a specific algorithm;

[0010] The display and output module displays real-time temperature data synchronously through the display screen.

[0011] Preferably, a light source is further included, which is used to provide sufficient radiation intensity and stability and emit near-infrared light to irradiate the gallium arsenide crystal.

[0012] Preferably, the central wavelength of the light source is in the wavelength range of about 845 nm to 945 nm, and the spectral range of the light source is from 320 nm to 1440 nm.

[0013] Preferably, the system further comprises a light source driving module, which is used to sequentially light up the light sources and adaptively adjust the light sources.

[0014] Preferably, the fiber optic optical path system includes an optical fiber and an optical path switching and coupling module, the optical fiber is used for transmitting optical signals, and the optical path switching and coupling module is used to control the switching of the light source and adjust the optical fiber channel to ensure that the optical signal can be accurately transmitted to the target area or returned to the detection equipment.

[0015] Preferably, the data acquisition and processing system includes a spectral data acquisition module, a signal processing and temperature calculation module, a data storage and management module, a communication interface module and a system power management module.

[0016] Preferably, the spectral data acquisition module receives the reflection spectrum of the gallium arsenide material through an optical fiber and transmits the spectral data. The signal processing and temperature calculation module is used to transmit the spectral data from the spectrometer to the main control unit, extract the wavelength information from the spectral data, and calculate the corresponding temperature value according to a pre-established wavelength-temperature relationship algorithm.

[0017] Preferably, the data storage and management module is used to save configuration files, historical data, temperature records and related parameters, and the system power management module is used to provide stable power supply for each sub-module to ensure the normal operation of the system.

[0018] Preferably, the communication interface module is used to implement data exchange and control with external devices.

[0019] Compared with the prior art, the present invention has the following beneficial effects: there is a clear relationship between the reflection spectrum of gallium arsenide material and temperature change, and high-precision temperature measurement can be achieved through accurate wavelength-temperature algorithm; the system can accurately extract wavelength information from spectral data and perform temperature calculation to provide accurate temperature values; since gallium arsenide material exhibits good optical properties over a wide temperature range, its reflection spectrum is highly stable to temperature changes; therefore, the fiber optic temperature sensing system based on gallium arsenide material can work stably in extreme environments and ensure data accuracy in long-term operation; the system provides stable power to each submodule through the power management module, ensuring that the system can operate stably at different times and avoiding the influence of power supply fluctuations on measurement results; the fiber optic temperature sensing system can monitor temperature changes in real time by quickly responding to changes in optical signals; since fiber optic transmission is free of current noise interference, the signal sensitivity is high and it can The system responds to tiny temperature changes, thereby improving the accuracy of temperature monitoring; the system's optical path switching and coupling module can flexibly control the switching of the light source and the adjustment of the optical fiber channel, thereby ensuring that the optical signal can be accurately transmitted to the target area or returned to the detection equipment, further enhancing the adaptability and flexibility of the system; the system not only supports communication between industrial equipment through the RS-485 bus and Modbus-RTU protocol, but also supports analog (4~20mA) and CAN bus interfaces to ensure seamless connection with various industrial control systems; for remote data monitoring, the system also supports wireless data transmission and can upload temperature data to the cloud platform for real-time monitoring, facilitating remote management and data storage; through the built-in DAC digital-to-analog converter, the system can accurately adjust the light intensity of each light source to ensure stable light source output under different environments, optimize the transmission quality of optical fiber signals, and improve measurement sensitivity and accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is the main loop logic diagram of the system of the present invention;

[0021] Figure 2 A block diagram of the peripheral circuit design of the present invention;

[0022] Figure 3 It is a data collection and processing flow chart of the present invention;

[0023] Figure 4 This is the minimum system diagram of the main control unit of the present invention;

[0024] Figure 5 A circuit for switching the I / O controlled light source of the present invention;

[0025] Figure 6 This is the light source voltage regulating circuit of the present invention. DETAILED DESCRIPTION

[0026] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0027] See also Figures 1-6 The present invention provides a technical solution: an optical fiber temperature sensing system based on gallium arsenide material, comprising: a temperature probe based on a gallium arsenide sensor chip, used to provide temperature information through changes in the reflection spectrum; an optical fiber optical path system, responsible for the transmission of incident light from a light source and reflected light from the gallium arsenide crystal; a photoelectric detection device, used to collect the reflection spectrum of the gallium arsenide crystal, perform photoelectric conversion, and transmit it to a main control unit; the main control unit, responsible for light source control, spectrum information demodulation, and temperature information output; a data acquisition and processing system, which collects and processes spectrum data and demodulates temperature information through a specific algorithm; and a display and output module, which synchronously displays real-time temperature data on a display screen.

[0028] It should be noted that in this embodiment, the temperature probe based on a GaAs sensor wafer utilizes a GaAs sensor wafer. The temperature probe senses temperature changes through changes in the reflection spectrum. The optical properties of GaAs enable it to generate a measurable signal from changes in the reflection spectrum with temperature, thereby providing accurate temperature information. A fiber optic system transmits the incident light from the light source and the light signal reflected by the temperature probe. Optical fiber, as the transmission medium, ensures stable and efficient signal transmission. Multimode fiber is used to minimize signal attenuation and ensure complete signal transmission to the photoelectric detection device. The photoelectric detection device is a spectrometer that collects the spectral signal reflected from the GaAs sensor wafer and converts it into an electrical signal. The sensitivity and response speed of the photodetector directly impact the accuracy of the system. By collecting the reflection spectrum, the photoelectric detection device can provide high-quality photoelectric signals, which are transmitted to the main control unit for processing. The main control unit is responsible for controlling the light source on and off, adjusting the light intensity, and managing data acquisition by the photoelectric detection device. Furthermore, the main control unit is responsible for demodulating the spectral information. By comparing the collected spectral data with a pre-established temperature-spectrum relationship model, the collected spectral data is converted into temperature information for final output. The display and output module is responsible for synchronously displaying real-time temperature data on a display screen, such as an LCD or LED. This module allows real-time monitoring of temperature changes detected by the sensor. It also provides alarm and notification functions, providing alerts when the temperature exceeds a preset range. The data acquisition and processing system is responsible for receiving, collecting, and processing spectral data from the photoelectric detection device. The system uses a specific algorithm to analyze the spectral data and uses demodulation technology to convert spectral changes into temperature information. The processed temperature data is then transmitted to the main control unit for subsequent processing and output. The temperature measurement system has multiple temperature measurement channels. After the main control unit selects a channel, it collects and analyzes the GaAs reflectance spectrum data to implement the system's temperature measurement function. The system data acquisition and processing process is as follows: After the system hardware is initialized, it first reads the configuration file burned into the ROM. The configuration file mainly calibrates the wavelength-temperature data comparison table. The spectrometer integration time is set based on the demodulated light intensity of the light source signal of the current temperature measurement channel. The spectrometer collects the light signal and demodulates the spectral data. The data processing program is called to obtain the wavelength signal from the spectral data. The temperature signal corresponding to the current wavelength is found in the wavelength lookup table. The temperature signal is displayed on the LCD screen, and then the next channel is switched to the next channel. The temperature value of each channel is measured in this cycle. The main process of the temperature measurement system mainly manages three modules: the UART communication module, the USB communication module, and the LCD display module. After startup, the main process enters the main loop program. The main control board communicates with the light source driver board via the UART serial port, controls the light source on the light source driver board, and activates the light source channel through the GPIO on the main control board.The spectrometer receives the reflected light signal from the sensor, and the main control board sends commands through the USB interface to control the spectrometer to demodulate the spectral data and call the temperature-wavelength algorithm relationship. The temperature value is demodulated based on the read spectral data and displayed on the LCD screen. This process is repeated after the system starts running to demodulate the temperature signal in real time.

[0029] In one embodiment, a light source and a light source driving module are further included. The light source is used to provide sufficient radiation intensity and stability to emit near-infrared light to irradiate the gallium arsenide crystal. The central wavelength of the light source is in the wavelength range of approximately 845nm to 945nm, and the spectral range of the light source is 320nm to 1440nm. The light source driving module is used to light up the light sources in sequence and adaptively adjust each light source.

[0030] It should be noted that in this embodiment, the light source is used to provide sufficient radiation intensity and stability. It emits near-infrared light, which irradiates the gallium arsenide crystal, causing changes in the reflection spectrum. The light source design must meet the following requirements:

[0031] The light source is driven by direct current and uses the LM2596 voltage regulator chip for voltage regulation. Combined with the DAC function of the microcontroller, the voltage output of the light source can be finely adjusted, thereby achieving dynamic adjustment of the light intensity to meet the needs of different temperature measurements.

[0032] Central wavelength: The central wavelength of the light source is in the range of 845nm to 945nm. This wavelength range is very suitable for the characteristics of GaAs materials and can effectively excite and respond to temperature changes.

[0033] Spectral range: The light source's spectral range is 320nm to 1440nm, ensuring coverage of a wide wavelength band, thereby capturing the various reflective spectral characteristics of the GaAs crystal and further enhancing the accuracy of the system.

[0034] The light source driver module controls the light source on and off and adaptively adjusts the brightness of each light source according to system requirements. This module includes:

[0035] Light source lighting control: gradually light up the light source to avoid instantaneous current overload and ensure stable light source output.

[0036] Brightness Adjustment: Based on the temperature sensor's requirements and environmental conditions, the light source's brightness is adaptively adjusted to ensure stable radiant intensity. The driver module precisely controls the light source's brightness using DAC (digital-to-analog converter) technology. The system's built-in DAC adjusts the light source's output amplitude. Controlling the DAC via a single-chip microcontroller allows precise adjustment of each light source's intensity. The system uses I / O control to switch each light source, turning different light source channels on and off via precise control signals. This allows for dynamic switching of light sources based on measurement needs, ensuring efficient system operation.

[0037] Stability management: The light source driver module also needs to ensure the stability of the light source to avoid light intensity fluctuations caused by long-term operation, which may affect the accuracy of temperature measurement.

[0038] The collaboration between the light source and the light driver module ensures the system's stable operation in various environments. The light source provides the necessary radiation intensity, while the light driver module adjusts the light source based on feedback, ensuring the system's reliability and stability in various usage scenarios.

[0039] The system exchanges data with the spectrometer in real time via serial communication (such as UART), acquiring reflectance spectral data. Spectral data is processed internally using an analysis algorithm and ultimately converted into temperature information. To exchange data with external devices, the system utilizes the RS-485 bus and Modbus-RTU protocol, enabling efficient and stable transmission of temperature data to external monitoring or other control systems. The system supports data output via 4-20mA analog signals, a widely used signal in industry that effectively reduces signal interference. Furthermore, the CAN bus is a commonly used interface in industrial production and suitable for real-time data exchange between devices. For wireless transmission, the system supports cloud-based access, enabling real-time data acquisition and display via a cloud platform, facilitating remote monitoring and management. The cloud platform centrally manages temperature data, facilitating data analysis and storage. Temperature information is transmitted to a TFT display via an SPI interface, visually displaying real-time temperature data for each channel. The TFT screen provides a clear, easy-to-read interface, facilitating on-site monitoring. The device's built-in memory allows for the storage and modification of relevant information, such as channel name, product model, specifications, and temperature alarm values. According to the temperature measurement model, the absorption edge wavelength of GaAs's reflection spectrum within the temperature range of 250K to 500K (-23.15°C to 226.85°C) is approximately 845nm to 945nm. Therefore, this design selected a light source with a central wavelength of 880nm, covering a spectral range of 320nm to 1440nm. This effectively matches the optical properties of GaAs material, enabling accurate temperature sensing.

[0040] In one embodiment, the fiber optic optical path system includes an optical fiber and an optical path switching and coupling module. The optical fiber is used to transmit optical signals. The optical path switching and coupling module is used to control the switching of the light source and adjust the optical fiber channel to ensure that the optical signal can be accurately transmitted to the target area or returned to the detection equipment. The data acquisition and processing system includes a spectral data acquisition module, a signal processing and temperature calculation module, a data storage and management module, a communication interface module, and a system power management module. The spectral data acquisition module receives the reflection spectrum of the gallium arsenide material through the optical fiber and generates spectral data. The signal processing and temperature calculation module is used to transmit the spectral data from the spectrometer to the main control unit. The wavelength information is extracted from the spectral data and the corresponding temperature value is calculated according to a pre-established wavelength-temperature relationship algorithm. The data storage and management module is used to save configuration files, historical data, temperature records, and related parameters. The system power management module is used to provide a stable power supply for each submodule to ensure the normal operation of the system. The communication interface module is used to realize data exchange and control with external devices.

[0041] It should be noted that in this embodiment, the fiber optic optical path system is used to transmit optical signals, transferring the optical signal emitted by the light source to the gallium arsenide material and receiving the reflected optical signal. The optical path switching and coupling module is used to control the light source on and off and adjust the optical fiber path. Optical path switching ensures that the optical signal is accurately transmitted to the target area or returned to the detection equipment. The coupling module also ensures effective coupling of the optical signal, reducing transmission loss and interference, and improving the sensitivity and stability of the system.

[0042] Data acquisition and processing system:

[0043] The system consists of multiple modules responsible for collecting, processing, and calculating spectral data received from optical fibers, storing and managing the results. The spectral data acquisition module receives optical signals reflected from the gallium arsenide material via optical fibers and converts these signals into spectral data. The signal processing and temperature calculation module receives spectral data transmitted from the spectrometer to the main control unit. It extracts wavelength information from the spectral data and calculates the corresponding temperature value based on a pre-established wavelength-temperature relationship algorithm. The data storage and management module stores system configuration files, historical data, temperature records, and other relevant parameters. This module ensures long-term data storage for subsequent analysis and retrieval. The system power management module provides stable power to each submodule, ensuring normal operation of the system under different operating conditions. The communication interface module facilitates data exchange and control with external devices. Communication interfaces typically include RS-485, Modbus-RTU, or other industry-standard interfaces, enabling transmission of measurement data to remote monitoring systems or integration with other devices.

[0044] Spectral data acquisition and temperature calculation process:

[0045] The optical fiber receives the light signal reflected from the gallium arsenide material;

[0046] These reflectance spectra are converted into digital data by a spectral data acquisition module;

[0047] The signal processing and temperature calculation module analyzes the spectral data and extracts the wavelength information in the spectrum;

[0048] Using the preset relationship algorithm between wavelength and temperature, the current temperature value is calculated;

[0049] The calculation results are transmitted to the data storage and management module for recording and storage.

[0050] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. The fiber optic temperature sensing system based on gallium arsenide material is characterized by: include: GaAs sensor wafer-based temperature probes provide temperature information through changes in the reflected light spectrum. Fiber optic optical system, responsible for the transmission of incident light from the light source and reflected light from the gallium arsenide crystal; A photoelectric detection device is used to collect the reflection spectrum of the gallium arsenide crystal, perform photoelectric conversion, and transmit it to the main control unit; The main control unit is responsible for light source control, spectrum information demodulation and temperature information output; Data acquisition and processing system, which collects and processes spectral data and demodulates temperature information through a specific algorithm; The display and output module displays real-time temperature data synchronously through the display screen.

2. The fiber optic temperature sensing system based on gallium arsenide material according to claim 1, characterized in that: The invention also includes a light source, which is used to provide sufficient radiation intensity and stability and emit near-infrared light to irradiate the gallium arsenide crystal.

3. The fiber optic temperature sensing system based on gallium arsenide material according to claim 1, characterized in that: The central wavelength of the light source is in the wavelength range of about 845nm to 945nm, and the spectrum range of the light source is from 320nm to 1440nm.

4. The fiber optic temperature sensing system based on gallium arsenide material according to claim 1, characterized in that: It also includes a light source driving module, which is used to light up the light sources in sequence and adaptively adjust the light sources.

5. The fiber optic temperature sensing system based on gallium arsenide material according to claim 1, characterized in that: The fiber optic light path system includes an optical fiber and an optical path switching and coupling module. The optical fiber is used to transmit optical signals. The optical path switching and coupling module is used to control the switching of the light source and adjust the optical fiber channel to ensure that the optical signal can be accurately transmitted to the target area or returned to the detection equipment.

6. The fiber optic temperature sensing system based on gallium arsenide material according to claim 1, characterized in that: The data acquisition and processing system includes a spectrum data acquisition module, a signal processing and temperature calculation module, a data storage and management module, a communication interface module and a system power management module.

7. The fiber optic temperature sensing system based on gallium arsenide material according to claim 6, characterized in that: The spectral data acquisition module receives the reflection spectrum of the gallium arsenide material through the optical fiber and transmits the spectral data. The signal processing and temperature calculation module is used to transmit the spectral data from the spectrometer to the main control unit, extract the wavelength information from the spectral data, and calculate the corresponding temperature value according to the wavelength-temperature relationship algorithm established in advance.

8. The fiber optic temperature sensing system based on gallium arsenide material according to claim 6, characterized in that: The data storage and management module is used to save configuration files, historical data, temperature records and related parameters, and the system power management module is used to provide stable power to each submodule to ensure the normal operation of the system.

9. The fiber optic temperature sensing system based on gallium arsenide material according to claim 6, characterized in that: The communication interface module is used to implement data exchange and control with external devices.

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