High-voltage switch cabinet tubular bus temperature measurement method and system based on fluorescent optical fiber sensing

Abstract

The invention relates to the technical field of tube bus bar temperature measurement, in particular to a high-voltage switch cabinet tube bus bar temperature measurement method and system based on fluorescent optical fiber sensing, and the method comprises the following steps: distributing a unique and orthogonal pseudo-random code for each tube bus bar, carrying out the intensity modulation of an excitation light source based on the pseudo-random code, receiving the excitation light through an optical fiber coupler, and carrying out the light splitting; each path of excitation light is transmitted to each optical fiber probe; fluorescent light is obtained and reversely transmitted through the fluorescent optical fiber; acquiring fluorescence transmitted to the second surface of the first optical filter by using a photoelectric detector to obtain a mixed fluorescence signal; and separating the mixed fluorescence signal based on the pseudo-random code to obtain an independent fluorescence signal, demodulating the independent fluorescence signal to obtain fluorescence lifetime information of each tubular bus bar, and comparing the fluorescence lifetime information of each tubular bus bar with a pre-calibrated fluorescence lifetime-temperature curve to obtain the real-time temperature of each tubular bus bar. Based on the code division multiple access technology, excitation light is modulated through orthogonal pseudo-random codes, and simultaneous and independent temperature measurement of three tubular buses can be achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of temperature measurement of pipe buses, and more particularly, to a method and system for measuring the temperature of pipe buses in high-voltage switchgear cabinets based on fluorescence optical fiber sensing. Background Art

[0002] Compared with traditional temperature sensors, optical fiber temperature sensors have many advantages. For example, light waves are not affected by electromagnetic interference; optical fibers have a wide working frequency band, a large dynamic range, and are a low-loss transmission line; optical fibers are themselves non-electric, small in size, light in weight, easy to bend, and have good radiation resistance. Therefore, optical fiber temperature sensors are particularly suitable for use in harsh environments such as flammable and explosive areas, areas with strict space limitations, and strong electromagnetic interference, solving the temperature measurement problems that cannot be solved by traditional methods. Among them, fluorescence optical fiber temperature sensors achieve temperature sensing by detecting the fluorescence intensity or fluorescence lifetime according to the one-to-one correspondence between the fluorescence parameters emitted by fluorescent substances after being excited, and have now been widely used in many fields such as power systems, buildings, aerospace, medical care, food processing, petrochemical engineering, and ocean development.

[0003] In many application scenarios, it is often necessary to monitor multi-point temperature measurement. For example, in the power system, it is necessary to measure the online temperature rise of the pipe buses in high-voltage switchgear cabinets. However, at present, most fluorescence optical fiber temperature measurement systems can only be used for single-point temperature detection. Therefore, when multi-point temperature measurement is required, if multiple sets of single-point temperature measurement systems are used, the system cost will be greatly increased.

[0004] Adopting a dynamic coupling optical multiplexing scheme, that is, respectively exciting multiple fluorescence probes through a conversion device and performing corresponding measurements, can achieve multi-channel temperature monitoring, such as the research on multi-channel fluorescence optical fiber temperature measurement systems published by Jia Danping et al. However, the disadvantages of this method are as follows: on the one hand, the complex dynamic coupling device introduces dynamic coupling errors, affecting the stability of temperature measurement; on the other hand, the temperatures of each channel need to sequentially switch the optical path for measurement and cannot be obtained simultaneously.

[0005] Based on this, how to achieve multi-point simultaneous temperature measurement of the pipe buses in high-voltage switchgear cabinets is a technical problem that needs to be solved urgently at present. Summary of the Invention

[0006] The purpose of the present invention is to provide a method and system for measuring the temperature of pipe buses in high-voltage switchgear cabinets based on fluorescence optical fiber sensing, so as to solve the technical problem of how to achieve multi-point simultaneous temperature measurement of the pipe buses in high-voltage switchgear cabinets.

[0007] The present invention is achieved through the following technical solutions: A method for measuring the temperature of pipe buses in high-voltage switchgear cabinets based on fluorescence optical fiber sensing, in which an optical fiber probe is provided on the fluorescence optical fiber, a fluorescent substance is provided on the optical fiber probe, and a path of fluorescence optical fiber is configured on each of the pipe bus A, pipe bus B, and pipe bus C of the high-voltage switchgear cabinet. The method includes the following steps:

[0008] Assign unique and orthogonal pseudo-random codes to the busbars A, B, and C of the high-voltage switchgear, and intensity-modulate the excitation light source based on the pseudo-random codes to make it output excitation light carrying the pseudo-random codes;

[0009] Use an optical fiber coupler to receive the excitation light reflected from the first surface of the first filter for splitting, and transmit each path of the split excitation light to the optical fiber probes corresponding to the respective busbars through fluorescence optical fibers, where the first surface of the first filter is arranged on the outgoing light path of the excitation light source;

[0010] Obtain the fluorescence emitted by the fluorescent substance on the optical fiber probe after being excited by the excitation light, and reversely transmit it to the first filter through the fluorescence optical fiber, and use the first filter to separate the excitation light and the fluorescence;

[0011] Use a photodetector to obtain the fluorescence transmitted to the second surface of the first filter to obtain a mixed fluorescence signal containing mixed coding information, where the photodetector is arranged on the outgoing light path of the second surface of the first filter;

[0012] Separate the mixed fluorescence signal based on the pseudo-random code to obtain independent fluorescence signals corresponding to the respective busbars;

[0013] Demodulate the independent fluorescence signal to obtain the fluorescence lifetime information of each busbar;

[0014] Compare the fluorescence lifetime information of each busbar with the pre-calibrated fluorescence lifetime-temperature curve to obtain the real-time temperature of each busbar.

[0015] According to a preferred embodiment, separating the mixed fluorescence signal based on the pseudo-random code is expressed as:

[0016]

[0017] In the above formula, R i (τ) represents the independent fluorescence signal corresponding to the i-th busbar, K is the total number of sampling points, S(k) represents the value of the mixed fluorescence signal at the discrete sampling point k, C i (k - τ) represents the value of the pseudo-random code sequence corresponding to the i-th busbar at the moment k - τ, C i Is the pseudo-random code assigned to the i-th busbar, and k - τ represents a shift operation of delaying the pseudo-random code by τ for correlation calculation with the mixed fluorescence signal S(k) at different moments.

[0018] According to a preferred embodiment, before separating the mixed fluorescence signal, the method further includes:

[0019] In the initialization stage, short pulse excitation light is sequentially sent to each busbar separately, and the time difference from the emission of the excitation light to the reception of the fluorescence signal by the photodetector is measured for each busbar;

[0020] The transmission delay of each busbar is compensated using the time difference, so that the pseudo-random code is aligned in time with the independent fluorescence signal corresponding to each busbar in the mixed fluorescence signal.

[0021] According to a preferred embodiment, the independent fluorescence signal is demodulated and expressed as:

[0022] R i (τ) = R i (0)·e -t / L

[0023] In the above formula, R i (0) represents the initial light intensity of the independent fluorescence signal of the i-th busbar when the excitation light is turned off, t is the measurement time, and L is the fluorescence lifetime.

[0024] The present invention also provides a temperature measurement system for busbars of high-voltage switchgear based on fluorescence optical fiber sensing, which applies the method as described above. The system includes:

[0025] An excitation light source driving unit, configured to allocate unique and orthogonal pseudo-random codes for busbar A, busbar B, and busbar C of the high-voltage switchgear, and intensity-modulate the excitation light source based on the pseudo-random codes so that it outputs excitation light carrying the pseudo-random codes;

[0026] An excitation light source, configured to output excitation light carrying the pseudo-random codes;

[0027] A first filter, whose first surface is disposed on the outgoing light path of the excitation light source, configured to reflect the excitation light emitted by the excitation light source through the first surface and separate the excitation light from the fluorescence;

[0028] An optical fiber coupler, configured to receive the excitation light reflected by the first surface of the first filter for splitting, and transmit each path of the split excitation light to the optical fiber probe corresponding to each busbar through the fluorescence optical fiber;

[0029] An optical fiber probe, configured to acquire the fluorescence emitted after the fluorescent substance is excited by the excitation light, and transmit it back to the first filter through the fluorescence optical fiber in the reverse direction;

[0030] A photodetector, which is disposed on the outgoing light path of the second surface of the first filter, configured to acquire the fluorescence transmitted to the second surface of the first filter, and obtain a mixed fluorescence signal containing mixed coding information;

[0031] An analysis unit, configured to separate the mixed fluorescence signals based on the pseudo-random code, obtain independent fluorescence signals corresponding to each busbar, perform demodulation processing on the independent fluorescence signals to obtain the fluorescence lifetime information of each busbar, and compare the fluorescence lifetime information of each busbar with a pre-calibrated fluorescence lifetime-temperature curve to obtain the real-time temperature of each busbar.

[0032] According to a preferred embodiment, it further includes a second filter. The second filter is disposed on the incident light path of the photodetector and is configured to receive the fluorescence transmitted to the second surface of the first filter for filtering processing, and reflect the filtered fluorescence into the photodetector.

[0033] According to a preferred embodiment, the fluorescence optical fiber is a quartz optical fiber.

[0034] According to a preferred embodiment, the photodetector is a silicon photodiode.

[0035] According to a preferred embodiment, it further includes a photoelectric conversion circuit. The silicon photodiode D1 is disposed in the photoelectric conversion circuit. The photoelectric conversion circuit further includes a resistor R1, a resistor R2, a resistor R3, a capacitor C1, a capacitor C2, and an operational amplifier U1.

[0036] Wherein, the first end of the silicon photodiode D1 is sequentially connected to the inverting input terminal of the operational amplifier U1, the first end of the resistor R3, and the first end of the capacitor C1. The second end of the resistor R3 and the second end of the capacitor C1 are connected to the output terminal of the operational amplifier U1. The positive terminal of the operational amplifier U1 is respectively connected to the first end of the resistor R1 and the first end of the resistor R2. The second end of the resistor R1, the positive power supply terminal of the operational amplifier U1, and the first end of the capacitor C2 are connected to the power supply voltage input. The second end of the resistor R2, the second end of the silicon photodiode D1, the negative power supply terminal of the operational amplifier U1, and the second end of the capacitor C2 are all grounded.

[0037] According to a preferred embodiment, it further includes a filtering circuit. The filtering circuit is connected to the output terminal of the operational amplifier U1.

[0038] The technical solution of the method and system for measuring the temperature of the busbar of a high-voltage switchgear based on fluorescence optical fiber sensing provided by the present invention has at least the following advantages and beneficial effects: (1) Based on the code division multiple access technology, by modulating the excitation light with an orthogonal pseudo-random code, the simultaneous independent temperature measurement of three busbars can be realized; (2) By combining transmission delay compensation, the independent fluorescence signals of each busbar can be accurately separated. After demodulating the fluorescence lifetime information, the real-time temperature of each busbar can be accurately obtained according to the fluorescence lifetime-temperature correspondence relationship, improving the temperature measurement accuracy and reliability; (3) The application of the orthogonal pseudo-random code makes the signals of each busbar independent. The correlation detection of the mixed fluorescence signal only produces a significant peak for the matching signal, which can effectively suppress the interference of other channels and external noise, and ensure the stable transmission and accurate detection of the signal in a complex environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic flow chart of the method for measuring the temperature of the busbar of a high-voltage switchgear based on fluorescence optical fiber sensing provided in Embodiment 1 of the present invention;

[0040] Figure 2 It is a schematic structural diagram of the system for measuring the temperature of the busbar of a high-voltage switchgear based on fluorescence optical fiber sensing provided in Embodiment 2 of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0041] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and illustrated herein can be arranged and designed in various different configurations.

[0042] Embodiment 1

[0043] Refer to Figure 1 as shown Figure 1 It is a schematic flow chart of a method for measuring the temperature of the busbar of a high-voltage switchgear based on fluorescence optical fiber sensing provided in an embodiment of the present invention; it should be noted that an optical fiber probe is provided on the fluorescence optical fiber, and a fluorescent substance is provided on the optical fiber probe, and the fluorescent substance can emit fluorescence when excited; a path of fluorescence optical fiber is configured for each of the busbar A, busbar B, and busbar C corresponding to the high-voltage switchgear in the present invention.

[0044] Specifically in this embodiment, the method for measuring the temperature of the busbar of a high-voltage switchgear based on fluorescence optical fiber sensing combines the code division multiple access (CDMA) technology. By modulating the excitation light with an orthogonal pseudo-random code, the simultaneous independent temperature measurement of three busbars can be realized, and the steps are as follows:

[0045] Step 1: Encoding and modulating the excitation light source; In some embodiments of this embodiment, unique and orthogonal pseudo-random codes are assigned to the busbars A, B, and C of the high-voltage switchgear. Based on the pseudo-random codes, intensity modulation is performed on the excitation light source to make it output excitation light carrying the pseudo-random codes.

[0046] It should be noted that the pseudo-random codes have good orthogonality, which can effectively reduce interference between channels; in the busbar temperature measurement scenario, unique pseudo-random codes are assigned to each busbar to modulate the excitation light. After being excited, the fluorescence signals of each busbar carry the corresponding pseudo-random code characteristics, and these signals are mixed together during the transmission process; when detecting later, it is necessary to perform correlation operations between the mixed fluorescence signals and each pseudo-random code respectively to separate the fluorescence signals. Due to the good orthogonality of the pseudo-random codes, the signal components of other channels that do not match a certain pseudo-random code in the mixed fluorescence signals have extremely small contributions to the operation results because the cross-correlation values approach zero during the correlation operation, and will not interfere with the detection of the busbar signals, thus effectively reducing interference between channels. Only the channel signals that match this pseudo-random code will generate significant correlation peaks, thereby realizing the accurate separation and independent detection of each busbar signal.

[0047] Specifically, in this embodiment, through code division multiple access technology, the fluorescence signals of different busbars are distinguished by coding, which can avoid the complexity of multi-frequency component modulation and realize efficient and accurate detection of the temperature of three busbars.

[0048] Step 2: Optical path transmission of the excitation light; In some embodiments of this embodiment, an optical fiber coupler is used to receive the excitation light reflected from the first surface of the first filter for splitting, and each path of the split excitation light is transmitted through a fluorescence optical fiber to an optical fiber probe corresponding to each busbar. Among them, the first surface of the first filter is arranged on the outgoing light path of the excitation light source; further, the fluorescence emitted after the fluorescent substance on the optical fiber probe is excited by the excitation light is obtained and reversely transmitted to the first filter through the fluorescence optical fiber, and the excitation light and the fluorescence are separated by using the first filter; further, a photodetector is used to obtain the fluorescence transmitted to the second surface of the first filter to obtain a mixed fluorescence signal containing mixed coding information, where the photodetector is arranged on the outgoing light path of the second surface of the first filter;

[0049] Step 3: Separation of the mixed fluorescence signal; In this step, the mixed fluorescence signal is separated based on the pseudo-random code to obtain independent fluorescence signals corresponding to each busbar; in some embodiments, separating the mixed fluorescence signal based on the pseudo-random code is expressed as:

[0050]

[0051] In the above formula, R i$(\tau)$ represents the independent fluorescence signal corresponding to the $i$-th busbar, $K$ is the total number of sampling points, $S(k)$ represents the value of the mixed fluorescence signal at the discrete sampling point $k$, and $C$ i $(k - \tau)$ represents the value of the pseudo-random code sequence corresponding to the $i$-th busbar at the moment $k - \tau$, and $C$ i is the pseudo-random code assigned to the $i$-th busbar. $k - \tau$ represents a shift operation of delaying the pseudo-random code by $\tau$ in time, which is used for correlation calculation at different moments with the mixed fluorescence signal $S(k)$.

[0052] Specifically, in this embodiment, by applying orthogonal pseudo-random codes, the signals of each busbar are made independent of each other. For the correlation detection of the mixed fluorescence signal, only the matching signal generates a significant peak, which can effectively suppress interference from other channels and external noise, and ensure the stable transmission and accurate detection of the signal in a complex environment.

[0053] In addition, to solve the deviation introduced by the difference in the transmission distance of the fluorescence optical fibers corresponding to each busbar, before separating the mixed fluorescence signal, this embodiment of the method further includes: in the initialization stage, short pulse excitation light is sequentially sent to each busbar alone, and the time difference between the emission of the excitation light from each busbar and the reception of the fluorescence signal by the photodetector is measured; the transmission delay of each busbar is compensated by using the time difference, so that the pseudo-random code is aligned with the independent fluorescence signal corresponding to each busbar in the mixed fluorescence signal in time.

[0054] Specifically, by combining transmission delay compensation in this embodiment, the independent fluorescence signals of each busbar can be accurately separated. After demodulating the fluorescence lifetime information, the real-time temperature of each busbar can be accurately obtained according to the fluorescence lifetime-temperature correspondence relationship, improving the temperature measurement accuracy and reliability.

[0055] Step Four: Demodulation processing of the fluorescence signal; in this step, the independent fluorescence signal is demodulated to obtain the fluorescence lifetime information of each busbar; in some embodiments, the demodulation processing of the independent fluorescence signal is expressed as:

[0056] $R$ i $(\tau)=R$ i $(0)\cdot e$ -t / L

[0057] In the above formula, $R$ i $(0)$ represents the initial light intensity of the independent fluorescence signal of the $i$-th busbar when the excitation light is turned off, $t$ is the measurement time, and $L$ is the fluorescence lifetime.

[0058] Step Five: Curve comparison; in this step, the fluorescence lifetime information of each busbar is compared with the pre-calibrated fluorescence lifetime-temperature curve, and the real-time temperature of each busbar can be obtained.

[0059] Embodiment 2

[0060] This embodiment provides a temperature measurement system for the busbars of a high-voltage switchgear based on fluorescence fiber optic sensing, which is based on the technical solution provided in Embodiment 1 and applies the method described in Embodiment 1; see Figure 2 As shown, the system includes: an excitation light source driving unit, an excitation light source, a first filter, an optical fiber coupler, an optical fiber probe, a photodetector, and an analysis unit.

[0061] Among them, the excitation light source driving unit is configured to allocate unique and orthogonal pseudo-random codes to busbar A, busbar B, and busbar C of the high-voltage switchgear, and intensity-modulate the excitation light source based on the pseudo-random codes to output excitation light carrying the pseudo-random codes.

[0062] The excitation light source is configured to output excitation light carrying pseudo-random codes; the first filter is configured such that its first surface is disposed on the outgoing light path of the excitation light source, reflects the excitation light emitted by the excitation light source through the first surface, and separates the excitation light from the fluorescence; the optical fiber coupler is configured to receive the excitation light reflected by the first surface of the first filter for splitting, and transmit the split excitation light to the optical fiber probes corresponding to each busbar through the fluorescence optical fiber; in some embodiments of this embodiment, the fluorescence optical fiber is a quartz optical fiber; the optical fiber probe is configured to acquire the fluorescence emitted after the fluorescent substance is excited by the excitation light, and transmit it back to the first filter through the fluorescence optical fiber; the photodetector is disposed on the outgoing light path of the second surface of the first filter, and is configured to acquire the fluorescence transmitted to the second surface of the first filter to obtain a mixed fluorescence signal containing mixed coding information; in some embodiments, the photodetector is a silicon photodiode.

[0063] The analysis unit is configured to separate the mixed fluorescence signal based on the pseudo-random code to obtain independent fluorescence signals corresponding to each busbar, perform demodulation processing on the independent fluorescence signals to obtain the fluorescence lifetime information of each busbar, and compare the fluorescence lifetime information of each busbar with a pre-calibrated fluorescence lifetime-temperature curve to obtain the real-time temperature of each busbar.

[0064] Further, the system further includes a second filter, which is disposed on the incident light path of the photodetector, and is configured to receive the fluorescence transmitted to the second surface of the first filter for filtering processing, and reflect the filtered fluorescence into the photodetector.

[0065] Further, the system further includes a photoelectric conversion circuit. The silicon photodiode D1 is disposed in the photoelectric conversion circuit. The photoelectric conversion circuit further includes a resistor R1, a resistor R2, a resistor R3, a capacitor C1, a capacitor C2, and an operational amplifier U1. Among them, the first end of the silicon photodiode D1 is sequentially connected to the inverting input end of the operational amplifier U1, the first end of the resistor R3, and the first end of the capacitor C1. The second end of the resistor R3 and the second end of the capacitor C1 are connected to the output end of the operational amplifier U1. The positive extreme end of the operational amplifier U1 is respectively connected to the first end of the resistor R1 and the first end of the resistor R2. The second end of the resistor R1, the positive power supply end of the operational amplifier U1, and the first end of the capacitor C2 are connected to the power supply voltage input. The second end of the resistor R2, the second end of the silicon photodiode D1, the negative power supply end of the operational amplifier U1, and the second end of the capacitor C2 are all grounded. Specifically, since the fluorescence signal is relatively weak, the above photoelectric conversion circuit can further amplify the signal, improve the signal-to-noise ratio of the fluorescence signal, and make the signal as distortion-free as possible.

[0066] Further, a filtering circuit is further included. The filtering circuit is connected to the output end of the operational amplifier U1 and can process the signal to eliminate the interference of high-frequency noise to further improve the signal-to-noise ratio of the system.

[0067] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A temperature measurement method for the busbar of a high-voltage switchgear based on fluorescence optical fiber sensing. An optical fiber probe is provided on the fluorescence optical fiber, and a fluorescent substance is provided on the optical fiber probe. It is characterized in that, One fluorescence optical fiber is arranged on each of the busbars A, B, and C of the high-voltage switchgear. The method includes the following steps: Assign unique and orthogonal pseudo-random codes to the busbars A, B, and C of the high-voltage switchgear, and intensity-modulate the excitation light source based on the pseudo-random codes to make it output excitation light carrying the pseudo-random codes; Use an optical fiber coupler to receive the excitation light reflected by the first surface of the first filter for splitting, and transmit the split excitation lights to the optical fiber probes corresponding to the respective busbars through the fluorescence optical fibers. Among them, the first surface of the first filter is arranged on the outgoing light path of the excitation light source; Obtain the fluorescence emitted by the fluorescent substance on the optical fiber probe after being excited by the excitation light, and reversely transmit it to the first filter through the fluorescence optical fiber, and use the first filter to separate the excitation light and the fluorescence; Use a photodetector to obtain the fluorescence transmitted to the second surface of the first filter to obtain a mixed fluorescence signal containing mixed coding information. Among them, the photodetector is arranged on the outgoing light path of the second surface of the first filter; Separate the mixed fluorescence signal based on the pseudo-random codes to obtain independent fluorescence signals corresponding to the respective busbars; Perform demodulation processing on the independent fluorescence signals to obtain the fluorescence lifetime information of the respective busbars; Compare the fluorescence lifetime information of the respective busbars with the pre-calibrated fluorescence lifetime-temperature curve to obtain the real-time temperature of the respective busbars.

2. The temperature measurement method for the busbar of a high-voltage switchgear based on fluorescence optical fiber sensing according to claim 1, wherein, Separate the mixed fluorescence signal based on the pseudo-random codes, which is expressed as: In the above formula, R i (τ) represents the independent fluorescence signal corresponding to the i-th busbar tube, K is the total number of sampling points, S(k) represents the value of the mixed fluorescence signal at the discrete sampling point k, C i (k - τ) represents the value of the pseudo-random code sequence corresponding to the i-th busbar tube at the moment k - τ, C i is the pseudo-random code assigned to the i-th busbar tube, and k - τ represents the shift operation of delaying the pseudo-random code by time τ, which is used for the correlation calculation at different moments with the mixed fluorescence signal S(k).

3. The temperature measurement method for the busbar of a high-voltage switchgear based on fluorescence optical fiber sensing according to claim 2, wherein Before separating the mixed fluorescence signal, the method further includes: In the initialization stage, sequentially send short-pulse excitation light to each busbar alone, and measure the time difference from when the excitation light is emitted to when the fluorescence signal is received by the photodetector for each busbar; Use the time difference to supplement the transmission delay of each busbar to align the pseudo-random codes with the independent fluorescence signals corresponding to the respective busbars in the mixed fluorescence signal in terms of time.

4. The method for measuring the temperature of the busbar of a high-voltage switchgear based on fluorescence optical fiber sensing according to claim 3, wherein Perform demodulation processing on the independent fluorescence signals, which is expressed as: R i R(τ) = i R(0)·e -t / L In the above formula, R i (0) represents the initial light intensity of the independent fluorescence signal of the i-th pipe busbar when the excitation light is turned off, t is the measurement time, and L is the fluorescence lifetime.

5. A temperature measurement system for the busbar of a high-voltage switchgear based on fluorescence optical fiber sensing, characterized in that, Applied to the method according to any one of claims 1 to 4, the system includes: An excitation light source driving unit configured to assign unique and orthogonal pseudo-random codes to the busbars A, B, and C of the high-voltage switchgear, and intensity-modulate the excitation light source based on the pseudo-random codes to make it output excitation light carrying the pseudo-random codes; An excitation light source configured to output excitation light carrying the pseudo-random codes; A first filter, the first surface of which is arranged on the outgoing light path of the excitation light source, and is configured to reflect the excitation light emitted by the excitation light source through the first surface and separate the excitation light and the fluorescence; An optical fiber coupler configured to receive the excitation light reflected by the first surface of the first filter for splitting, and transmit the split excitation lights to the optical fiber probes corresponding to the respective busbars through the fluorescence optical fibers; An optical fiber probe configured to obtain the fluorescence emitted by the fluorescent substance after being excited by the excitation light, and reversely transmit it to the first filter through the fluorescence optical fiber; A photodetector, the photodetector is arranged on the outgoing light path of the second surface of the first filter, and is configured to obtain the fluorescence transmitted to the second surface of the first filter to obtain a mixed fluorescence signal containing mixed coding information; An analysis unit, configured to separate the mixed fluorescence signals based on the pseudo-random code to obtain independent fluorescence signals corresponding to each busbar, perform demodulation processing on the independent fluorescence signals to obtain the fluorescence lifetime information of each busbar, and compare the fluorescence lifetime information of each busbar with a pre-calibrated fluorescence lifetime-temperature curve to obtain the real-time temperature of each busbar.

6. The temperature measurement system for the busbar of a high-voltage switchgear based on fluorescence optical fiber sensing according to claim 5, wherein It further includes a second filter, which is arranged on the incident optical path of the photodetector and is configured to receive the fluorescence transmitted to the second surface of the first filter for filtering processing, and reflect the filtered fluorescence into the photodetector.

7. The temperature measurement system for the busbar of a high-voltage switchgear based on fluorescence optical fiber sensing according to claim 4, wherein The fluorescence optical fiber is a quartz optical fiber.

8. The temperature measurement system for the busbar of a high-voltage switchgear based on fluorescence optical fiber sensing according to claim 4, wherein The photodetector is a silicon photodiode.

9. The temperature measurement system for the busbar of a high-voltage switchgear based on fluorescence optical fiber sensing according to claim 8, characterized in that, It further includes a photoelectric conversion circuit. The silicon photodiode D1 is arranged in the photoelectric conversion circuit. The photoelectric conversion circuit further includes a resistor R1, a resistor R2, a resistor R3, a capacitor C1, a capacitor C2, and an operational amplifier U1. Wherein, the first end of the silicon photodiode D1 is sequentially connected to the inverting input end of the operational amplifier U1, the first end of the resistor R3, and the first end of the capacitor C1. The second end of the resistor R3 and the second end of the capacitor C1 are connected to the output end of the operational amplifier U1. The positive terminal of the operational amplifier U1 is respectively connected to the first end of the resistor R1 and the first end of the resistor R2. The second end of the resistor R1, the positive power supply terminal of the operational amplifier U1, and the first end of the capacitor C2 are connected to the power supply voltage input. The second end of the resistor R2, the second end of the silicon photodiode D1, the negative power supply terminal of the operational amplifier U1, and the second end of the capacitor C2 are all grounded.

10. The temperature measurement system for the tube bus of a high-voltage switchgear based on fluorescence optical fiber sensing according to claim 9, characterized in that, It further includes a filtering circuit, and the filtering circuit is connected to the output end of the operational amplifier U1.

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