Switch cabinet state identification method and device based on spectrum ratio tracking

Abstract

The invention belongs to the technical field of switch cabinet state recognition, and particularly relates to a switch cabinet state recognition method and device based on spectrum ratio tracking. The identification method comprises the following steps: acquiring an internal optical signal of the switch cabinet; filtering the optical signals in the switch cabinet, extracting the optical signals of different wavebands, and converting the optical signals into electric signals; the optical signals of different wave bands comprise an optical signal of an ultraviolet wave band, an optical signal of an infrared wave band and an optical signal of a visible light wave band; processing the electric signal to obtain a digital signal; calculating spectrum ratios under different wave bands according to the digital signals; and based on the spectrum ratio, identifying the internal state of the switch cabinet by adopting a switch cabinet state identification criterion. The problem that an existing detection device is difficult to comprehensively reflect the operation state of internal equipment of the switch cabinet is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of switchgear status recognition, and particularly relates to a switchgear status recognition method and device based on spectral ratio tracking. Background Art

[0002] As an important switching device in the power system, the operating status of the switchgear is directly related to the safe and stable operation of the power grid. Traditional switchgear status monitoring methods mainly rely on the measurement of electrical quantities such as temperature, current, and voltage, and it is difficult to effectively reflect potential faults such as internal insulation aging and partial discharge in the switchgear. Optical sensing technology has the advantages of non-contact, anti-electromagnetic interference, and high sensitivity, and has been widely used in the field of power equipment status monitoring in recent years.

[0003] However, most of the existing switchgear optical sensing devices use single-wavelength or narrow-band spectral detection, making it difficult to distinguish abnormal discharge types inside the cabinet, resulting in inaccurate monitoring results. Secondly, traditional methods cannot effectively filter out ambient light interference, leading to a decline in monitoring accuracy and making it difficult to comprehensively reflect the operating status of the internal equipment of the switchgear. Summary of the Invention

[0004] The purpose of the present invention is to provide a switchgear status recognition method and device based on spectral ratio tracking, which solves the problem that the existing detection devices are difficult to comprehensively reflect the operating status of the internal equipment of the switchgear.

[0005] The present invention is realized through the following technical solutions: A switchgear status recognition method based on spectral ratio tracking includes the following steps: S1. Obtain the internal optical signal of the switchgear; S2. Filter the internal optical signal of the switchgear, extract optical signals in different bands, and convert the optical signals into electrical signals; The optical signals in different bands include optical signals in the ultraviolet band, optical signals in the infrared band, and optical signals in the visible light band; S3. Process the electrical signal to obtain a digital signal; S4. Calculate the spectral ratios in different bands according to the digital signal; Based on the spectral ratios, use the switchgear status recognition criterion to recognize the internal status of the switchgear.

[0006] Further, in S4, calculate the spectral ratios of different wavelengths according to the digital signal, and the expression is:

[0007] Wherein, is the spectral ratio in the ultraviolet band, is the spectral ratio in the infrared band, is the spectral ratio in the visible light band; is the digital signal intensity in the ultraviolet band, is the digital signal intensity in the infrared band, is the digital signal intensity in the visible light band.

[0008] Further, in S4, the criterion for identifying the switchgear state is specifically: When the switchgear is in a normal state, the range of the spectral ratio in different bands is: and ; When the switchgear is in a partial discharge state, the range of the spectral ratio in different bands is: or and ; When the switchgear is in an abnormal heating state, the range of the spectral ratio in different bands is: and ; Among them, is the standard spectral ratio in the ultraviolet band, is the standard spectral ratio in the infrared band.

[0009] Further, when it is recognized that the internal state of the switchgear conforms to the spectral ratio characteristics in the partial discharge fault or overheating fault state, an alarm is triggered.

[0010] The present invention also discloses a switchgear state recognition device based on spectral ratio tracking for implementing the switchgear state recognition method, including: A data acquisition module for acquiring the optical signal inside the switchgear; A filter extraction module for filtering the optical signal inside the switchgear, extracting the optical signals in different bands, and converting the optical signals into electrical signals; A signal processing module for processing the electrical signals to obtain digital signals; A data processing module for calculating the spectral ratio in different bands based on the digital signals; Based on the spectral ratio, the internal state of the switchgear is recognized by using the switchgear state recognition criterion.

[0011] Further, the filter extraction module is divided into a first module, a second module and a third module. The first module includes a silicon photomultiplier tube array and an ultraviolet filter mounted on the substrate of the silicon photomultiplier tube array, and is used for extracting the optical signal in the ultraviolet band and converting the optical signal into an electrical signal; The second module includes a silicon photomultiplier tube array and a visible light filter mounted on the substrate of the silicon photomultiplier tube array, which is used to extract the optical signal in the visible light band and convert the optical signal into an electrical signal; The third module includes a silicon photomultiplier tube array and an infrared filter mounted on the substrate of the silicon photomultiplier tube array, which is used to extract the optical signal in the infrared band and convert the optical signal into an electrical signal.

[0012] Furthermore, the signal processing module includes an amplifier, a band-pass filter, a multiplexer, and an analog-to-digital converter connected in sequence; The amplifier is used to amplify the weak current signal output by the silicon photomultiplier tube array; The band-pass filter is used to filter out the high-frequency noise and low-frequency interference in the amplified signal; The multiplexer is used to sequentially select the multiple output signals from the three modules to the analog-to-digital converter in a time-division multiplexing manner according to the preset timing logic, realizing the time-division acquisition and digital processing of multi-channel signals; The analog-to-digital converter is used to convert the analog signal into a digital signal and transmit it to the data processing module for processing.

[0013] Furthermore, the data processing module includes: A spectral ratio calculation unit, which is used to calculate the spectral ratios at different wavelengths; A state recognition unit, which is used to recognize the internal state of the switch cabinet based on the spectral ratios by using the switch cabinet state recognition criterion.

[0014] Furthermore, the switch cabinet state recognition criterion is specifically: When the switch cabinet is in a normal state, the spectral ratio ranges at different bands are: And ; When the switch cabinet is in a partial discharge state, the spectral ratio ranges at different bands are: Or And ; When the switch cabinet is in an abnormal heating state, the spectral ratio ranges at different bands are: And ; Among them, is the standard spectral ratio in the ultraviolet band, is the standard spectral ratio in the infrared band.

[0015] Furthermore, the switchgear status recognition device further includes an alarm module and a wireless communication module. When it detects that the spectral ratio characteristics conform to the spectral ratio characteristics in the case of partial discharge faults or overheating faults, it triggers an alarm and transmits the information to the upper computer or the remote monitoring center through the wireless communication module.

[0016] Compared with the prior art, the present invention has the following beneficial technical effects: The present invention discloses a switchgear status recognition method based on spectral ratio tracking. By acquiring optical signals in multiple bands (ultraviolet, infrared, visible light) inside the switchgear and performing filtering processing and electrical signal conversion on them, it can capture specific spectral characteristics emitted inside the switchgear under different states. Calculating the spectral ratios in these different bands can more effectively distinguish between normal states and abnormal states (such as overheating, discharge), thereby improving the accuracy and reliability of status recognition. This method utilizes spectral analysis technology and can achieve remote and real-time monitoring of the switchgear status without directly contacting the internal components of the switchgear. This reduces the work risks of maintenance personnel and at the same time avoids equipment damage or misoperation caused by direct contact. Through continuous tracking and analysis of the spectral ratios, abnormal spectral characteristics can be detected before equipment failures occur, realizing early warning. This helps to timely discover and handle potential problems, reduce power outage time and maintenance costs caused by equipment failures, and improve the stability and reliability of the power system. By synchronously collecting and calculating the ratios of ultraviolet, visible light, and infrared multi-band spectra, the recognition ability for partial discharge faults and overheating fault states is significantly improved, avoiding misjudgments caused by single-wavelength detection. Description of the Drawings

[0017] Figure 1 The composition of a switchgear status recognition device based on spectral ratio tracking of the present invention during simulation; Figure 2 The defect model of solid metal protrusions in the switchgear; Figure 3 The creepage defect model of the switchgear; Figure 4 The experimental device diagram used in the implementation scheme of the present invention; Figure 5 The result schematic diagram of Embodiment 4 and Embodiment 5 of the present invention; Figure 6 The flowchart of a switchgear status recognition method based on spectral ratio tracking of the invention. Detailed Embodiments

[0018] In order to make the objectives, technical solutions and advantages of the present invention more clear, the following further elaborates in detail in conjunction with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention, that is, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0019] The components described and illustrated in the drawings and embodiments of the present invention can be arranged and designed in various different configurations. Therefore, the detailed description of the embodiments of the present invention provided in the following drawings is not intended to limit the scope of the present invention to be protected, but merely represents a selected embodiment of the present invention. Based on the drawings and embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts fall within the protection scope of the present invention.

[0020] It should be noted that the term "comprising", "including" or any other variant is intended to cover non-exclusive inclusion, such that a process, element, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to the process, element, method, article or device.

[0021] The features and performance of the present invention are further described in detail below in conjunction with embodiments.

[0022] Embodiment 1 As Figure 6 shown, the present invention discloses a method for identifying the state of a switchgear based on spectral ratio tracking, including the following steps: S1. Obtain the optical signal inside the switchgear; S2. Perform filtering processing on the obtained optical signal inside the switchgear, extract optical signals in different bands, and convert the optical signals into electrical signals; The optical signals in different bands include optical signals in the ultraviolet band, optical signals in the infrared band, and optical signals in the visible light band; S3. Process the electrical signal to obtain a digital signal; S4. Calculate the spectral ratio in different bands according to the digital signal; Based on the spectral ratio, use the switchgear state identification criterion to identify the internal state of the switchgear.

[0023] In S1, sensors can be specifically arranged to obtain partial discharge optical signals.

[0024] Internal layout of switchgear: For some large switchgears, small optical sensors or fiber optic probes can be installed at key internal positions, such as busbar connection points, near switch contacts, and on the surface of insulators. These are the positions where partial discharges are likely to occur. By arranging sensors closely, optical signals can be collected more effectively. The sensors should be firmly fixed to avoid affecting the detection results due to vibrations or other factors of the switchgear.

[0025] External detection of switchgear: For cases where sensors cannot be directly installed inside the switchgear, external detection methods can be used. For example, an ultraviolet imager can be used to detect the inside through the observation window or gap of the switchgear, or a fiber optic sensor can be wound around the outside of the switchgear to collect the optical signals generated by internal partial discharges through the light transmission characteristics of the optical fiber.

[0026] In S4, calculate the spectral ratios of different wavelengths according to the digital signals. The expression is:

[0027] Among them, is the spectral ratio in the ultraviolet band, is the spectral ratio in the infrared band, is the spectral ratio in the visible light band; is the digital signal intensity in the ultraviolet band, is the digital signal intensity in the infrared band, is the digital signal intensity in the visible light band.

[0028] Embodiment 2 The present invention discloses a switchgear status recognition device based on spectral ratio tracking, including: A data acquisition module for acquiring the optical signals inside the switchgear: A filter extraction module for filtering the acquired optical signals, extracting the optical signals of different bands, and converting the optical signals into electrical signals; A signal processing module for processing the electrical signals to obtain digital signals; A data processing module for calculating the spectral ratios in different bands based on the digital signals; Based on the spectral ratios, use the switchgear status recognition criterion to recognize the internal status of the switchgear.

[0029] The switchgear status recognition device further includes an alarm module and a wireless communication module. When it is detected that the spectral ratio characteristics conform to the spectral ratio characteristics in the case of partial discharge faults or overheating faults, an alarm is triggered and sent to the upper computer through the wireless communication module.

[0030] Specifically, the alarm module includes a buzzer and an LED indicator light, which are used to emit an audible and visual alarm signal. When there is a significant difference between the calculated real-time spectral ratio and the spectral ratio under normal conditions, the alarm is triggered. The buzzer emits an alarm sound, and the LED indicator light flashes red. Different alarm levels are set according to the severity of the fault.

[0031] The wireless communication module includes a LoRa module and an antenna. The LoRa module uses the SX1278 chip of Semtech Corporation, with a working frequency of 433 MHz, a transmit power of 20 dBm, and a receive sensitivity of -148 dBm. The antenna uses a whip antenna in the 433 MHz band with a gain of 2 dBi, and is used to transmit the internal state information and fault alarm signal of the switch cabinet to the host computer or remote monitoring center.

[0032] The alarm time and alarm type are transmitted to the remote monitoring center through the wireless communication module, so as to realize the state monitoring and fault early warning of the switch cabinet.

[0033] In order to reduce the energy consumption of the wireless communication module sensor hardware, a low-power ARM chip is used as the controller of the sensor in the design, and the working mode, sleep mode and shutdown mode are set.

[0034] The sleep mode will reduce the power loss of the device. If the real-time discharge amount and spectral ratio fluctuation of the sensor are both below the warning threshold within 5 minutes, it will enter the sleep mode. After that, the device will calibrate the spectral ratio under normal conditions every 10 minutes.

[0035] Embodiment 3 From a hardware perspective, a switch cabinet sensing device designed by the present invention based on spectral ratio tracking mainly includes: a filter group, a silicon photomultiplier (SiPM) array, a signal processing module, and a data processing module.

[0036] The filter group includes an ultraviolet filter (center wavelength 365 nm), a visible light filter (center wavelength 550 nm), and an infrared filter (center wavelength 850 nm), which are respectively used to extract optical signals in the ultraviolet, visible, and infrared bands.

[0037] SiPM array: Four silicon photomultipliers (SiPMs) are used to form a 2*2 sensing array. Its spectral response range is 300 nm to 900 nm, the response speed reaches the ns level, and the peak wavelength is 420 nm; the filter group is mounted on the substrate of the SiPM array to convert the optical signal into an electrical signal.

[0038] The signal processing module includes an amplifier, a band-pass filter, a multiplexer, and a high-precision analog-to-digital converter (ADC). The amplifier is used to amplify the weak current signal output by the silicon photomultiplier tube array; The band-pass filter is used to filter out high-frequency noise and low-frequency interference in the amplified signal; The multiplexer is used to sequentially switch the output signals of multiple signal conditioning circuits to the analog-to-digital converter; The analog-to-digital converter is used to convert the analog signal into a digital signal and transmit it to the data processing module for processing.

[0039] The data processing module includes: A spectral ratio calculation unit for calculating the spectral ratios at different wavelengths; A state recognition unit for recognizing the internal state of the switchgear based on the spectral ratios using the switchgear state recognition criterion.

[0040] The state of the switchgear usually includes normal state, partial discharge state, overheating state, etc. The spectral ratio characteristics corresponding to different states are different. The following is a specific introduction: Normal state: When the switchgear is operating normally, the electrical equipment inside is in a stable working state without abnormal heating or discharging phenomena. At this time, the spectrum inside the switchgear mainly comes from ambient light and the weak thermal radiation emitted by the equipment itself.

[0041] The spectral ratio characteristics are relatively stable, the light intensity ratios of each band are relatively uniform, and there are no obvious peaks or abnormal spectral changes. For example, in the visible light band, the ratios of the three primary colors red, green, and blue are close to the ratio of ambient light; in the infrared band, the spectral ratio of thermal radiation also conforms to the temperature characteristics during normal operation of the equipment.

[0042] Partial discharge state: When partial discharge occurs inside the switchgear, light radiation of multiple wavelengths such as ultraviolet, visible, and infrared light will be generated. Partial discharge will decompose and ionize the insulating material, generating some characteristic spectral signals.

[0043] In terms of spectral ratio characteristics, the light intensity in the ultraviolet band will relatively increase, and the ratio with visible light or infrared light will change. For example, in some studies, it is found that the ratio of ultraviolet light to visible light during partial discharge is significantly higher than that in the normal state because a large number of ultraviolet photons are generated during the partial discharge process. In addition, in the visible light band, the light intensity of some specific colors may increase, such as blue or purple light, resulting in abnormal spectral ratios.

[0044] Overheating state: Overheating of the equipment inside the switchgear is a common fault state. The overheating may be caused by poor contact, excessive load, etc. When the temperature of the equipment rises, its thermal radiation will increase, and the spectral distribution will change.

[0045] In terms of the spectral ratio characteristics, the light intensity in the infrared band will increase significantly, and the ratio with the visible light band will increase. According to Wien's displacement law, when the temperature of an object rises, the peak wavelength of its thermal radiation will shift towards the short-wave direction. Therefore, in the overheating state, the intensity of the infrared light with a shorter wavelength increases more significantly, resulting in a change in the ratio of different bands within the infrared light. For example, the ratio of the mid-infrared band to the far-infrared band may increase with the increase in temperature.

[0046] Therefore, the present invention designs the switchgear state recognition criterion, specifically: When the switchgear is in the normal state, the spectral ratio range in different bands is: And ; When the switchgear is in the partial discharge state, the spectral ratio range in different bands is: Or And ; When the switchgear is in the abnormal heating state, the spectral ratio range in different bands is: And ; Among them, is the standard spectral ratio in the ultraviolet band, is the standard spectral ratio in the infrared band.

[0047] Embodiment 4 From a specific experimental perspective, in the design, it is necessary to place a discharge defect electrode in the switchgear partial discharge experimental device. Taking the actual acquisition process of the internal discharge signal of the switchgear as an example, the complete working principle of the present invention is illustrated.

[0048] Step 1: Device design and production The device design is as described in Embodiment 2. As Figure 1 shown, it includes a discharge defect electrode, a filter group, a SiPM array, a signal processing module, and a data processing module. And the integrated design of each circuit part is carried out to trial-produce a fast-response sensing device for switchgear based on spectral ratio tracking.

[0049] Place the discharge-defective electrode in the cable chamber of the switchgear. The SiPM array uses a 2×2 silicon photomultiplier (SIPM) array with a response speed reaching the nanosecond level. Arbitrarily select the substrates of three of the arrays, and respectively mount an ultraviolet filter (center wavelength 365 nm), a visible light filter (center wavelength 550 nm), and an infrared filter (center wavelength 850 nm) in front of the array substrates. The analog input channels of the signal processing module are 4, the amplifier uses a low-noise operational amplifier, and the band-pass filter uses an active filter.

[0050] The discharge-defective electrode is illustrated by taking the solid metal protrusion defect model as an example.

[0051] As Figure 2 shown, the solid metal protrusion defect model includes a needle electrode and a plate electrode, which are used to simulate the tip discharge caused by the metal protrusion inside the switchgear. Both the needle electrode and the plate electrode are made of brass, and the distance between the needle electrode and the plate electrode is 20 mm. The needle electrode adopts a hyperboloid shape, and its equivalent curvature radius is 50 μm and 100 μm.

[0052] Step 2: Spectral signal acquisition inside the switchgear Align the prototype of the fast-response sensing device for switchgear based on spectral ratio tracking with the switchgear equipped with the discharge-defective electrode through the cabinet observation window to directionally collect optical signals. The experimental platform is as shown in the appendix Figure 4 shown.

[0053] The working process is as follows: Switch the device from the shutdown mode to the working mode, apply an AC voltage of 10 kV, and the discharge-defective electrode generates a stable partial discharge optical signal. The optical signal sequentially passes through the ultraviolet filter, the visible light filter, and the infrared filter. The SiPM receives the optical signal after being spectrally processed by the filter components, extracts the optical signals in the ultraviolet, visible, infrared bands and the full band respectively, and converts them into electrical signals. The electrical signals of each channel are respectively transmitted to the corresponding analog input channels.

[0054] Step 3: Data processing of the internal discharge of the switchgear An amplifier amplifies the weak current signal output by the SiPM.

[0055] A band-pass filter filters out the high-frequency noise and low-frequency interference in the signal.

[0056] A multiplexer sequentially switches the output signals of the multiplex signal conditioning circuits to the ADC.

[0057] The ADC converts the analog signal into a digital signal and transmits it to the digital signal processing module for processing.

[0058] The data processing module calculates the spectral ratios in different bands, specifically: AsFigure 5 As shown in the figure, fault type 1 is the tip discharge model caused by internal metal protrusions, that is, the switchgear is in a partial discharge state. The spectral ratio in the ultraviolet band is 13.95%, the spectral ratio in the infrared band is 20.46%, and the spectral ratio in the visible light band is 65.95%.

[0059] Meet the ultraviolet spectral ratio or and the infrared spectral ratio The criterion shows the effectiveness of the switchgear state recognition criterion proposed by the present invention.

[0060] Among them, , .

[0061] Example 5 Different from Example 4, the discharge defect electrode is described by taking the creepage defect model as an example.

[0062] As Figure 3 shown, the creepage defect model includes a high-voltage rod electrode, a brass ground electrode, and an SMC insulating board. The high-voltage rod electrode and the brass ground electrode tightly press the insulating dielectric board to form an interface of insulating materials with a strong vertical component. The diameter of the brass rod electrode is 6 mm, and the thickness of the insulating dielectric board is 2 mm.

[0063] As Figure 5 shown, fault type 2 is the creepage defect model, that is, the switchgear is in a partial discharge state.

[0064] The discharge defect electrode adopts fault type 2. Through the above process, the data processing module finally calculates the spectral ratios in different bands, specifically: the spectral ratio in the ultraviolet band is 16.78%, the spectral ratio in the infrared band is 23.04%, and the spectral ratio in the visible light band is 60.18%.

[0065] Meet the ultraviolet spectral ratio or and the infrared spectral ratio The criterion shows the effectiveness of the switchgear state recognition criterion proposed by the present invention.

[0066] Among them, , .

[0067] Example 6 Different from Example 4, no discharge defect model is placed in the cable chamber of the switchgear, which is equivalent to the normal state inside the switchgear. The data processing module finally calculates the spectral ratios in different bands, specifically: the spectral ratio in the ultraviolet band is 8%, the spectral ratio in the infrared band is 15%, and the spectral ratio in the visible light band is 77%.

[0068] Meet ; ; It demonstrates the effectiveness of the switchgear status recognition criterion proposed by the present invention.

[0069] Among them, , .

[0070] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: modifications or equivalent replacements can still be made to the specific implementation manners of the present invention, and any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention should be covered by the protection scope of the claims of the present invention.

Claims

1. A method for identifying the state of a switchgear cabinet based on spectral ratio tracking, characterized in that, It includes the following steps: S1. Obtain the optical signals inside the switchgear cabinet; S2. Filter the optical signals inside the switchgear cabinet, extract optical signals of different bands, and convert the optical signals into electrical signals; The optical signals of different bands include optical signals in the ultraviolet band, optical signals in the infrared band, and optical signals in the visible light band; S3. Process the electrical signals to obtain digital signals; S4. Calculate the spectral ratios at different bands according to the digital signals; Based on the spectral ratios, use the switchgear cabinet status recognition criterion to recognize the internal status of the switchgear cabinet.

2. The method for identifying the state of a switchgear cabinet based on spectral ratio tracking according to claim 1, wherein, In S4, calculate the spectral ratios at different wavelengths according to the digital signals, and the expression is: Among them, is the spectral ratio in the ultraviolet band, is the spectral ratio in the infrared band, is the spectral ratio in the visible light band; is the digital signal intensity in the ultraviolet band, is the digital signal intensity in the infrared band, is the digital signal intensity in the visible light band.

3. A switchgear cabinet state recognition method based on spectral ratio tracking according to claim 2, characterized in that, In S4, the switchgear cabinet status recognition criterion is specifically: When the switchgear cabinet is in a normal state, the range of spectral ratios at different bands is: and ; When the switchgear cabinet is in a partial discharge state, the range of spectral ratios at different bands is: or and ; When the switchgear cabinet is in an abnormal heating state, the range of spectral ratios at different bands is: and ; Among them, is the standard spectral ratio in the ultraviolet band, is the standard spectral ratio in the infrared band.

4. A switchgear status recognition method based on spectral ratio tracking according to claim 1, characterized in that, When it is recognized that the internal status of the switchgear cabinet conforms to the spectral ratio characteristics in the partial discharge fault or overheating fault state, trigger an alarm.

5. A switchgear status recognition device based on spectral ratio tracking for implementing the switchgear status recognition method according to any one of claims 1-4, characterized in that, It includes: A data acquisition module for obtaining the optical signals inside the switchgear cabinet; A filter extraction module for filtering the optical signals inside the switchgear cabinet, extracting optical signals of different bands, and converting the optical signals into electrical signals; A signal processing module for processing the electrical signals to obtain digital signals; A data processing module for calculating the spectral ratios at different bands based on the digital signals; Based on the spectral ratios, use the switchgear cabinet status recognition criterion to recognize the internal status of the switchgear cabinet.

6. The state recognition device for switchgear based on spectral ratio tracking according to claim 5, characterized in that, The filter extraction module is divided into a first module, a second module, and a third module. The first module includes a silicon photomultiplier tube array and an ultraviolet filter mounted on the substrate of the silicon photomultiplier tube array, and is used to extract the optical signals in the ultraviolet band and convert the optical signals into electrical signals; The second module includes a silicon photomultiplier tube array and a visible light filter mounted on the substrate of the silicon photomultiplier tube array, and is used to extract the optical signals in the visible light band and convert the optical signals into electrical signals; The third module includes a silicon photomultiplier tube array and an infrared filter mounted on the substrate of the silicon photomultiplier tube array, and is used to extract the optical signals in the infrared band and convert the optical signals into electrical signals.

7. The state recognition device for switchgear based on spectral ratio tracking according to claim 6, characterized in that The signal processing module includes an amplifier, a band-pass filter, a multiplexer, and an analog-to-digital converter connected in sequence; The amplifier is used to amplify the weak current signal output by the silicon photomultiplier tube array; The band-pass filter is used to filter out the high-frequency noise and low-frequency interference in the amplified signal; The multiplexer is used to sequentially select the multiple output signals transmitted from the three modules to the analog-to-digital converter in a time-division multiplexing manner according to the preset timing logic, so as to realize the time-division acquisition and digital processing of multi-channel signals; The analog-to-digital converter is used to convert the analog signal into a digital signal and transmit it to the data processing module for processing.

8. A switchgear status recognition device based on spectral ratio tracking according to claim 5, characterized in that, The data processing module includes: A spectral ratio calculation unit for calculating the spectral ratios at different wavelengths; A status recognition unit for recognizing the internal status of the switchgear cabinet based on the spectral ratios by using the switchgear cabinet status recognition criterion.

9. The state recognition device for switchgear based on spectral ratio tracking according to claim 5, wherein The switchgear cabinet status recognition criterion is specifically: When the switchgear is in the normal state, the spectral ratio ranges under different wavelength bands are as follows: and ; When the switchgear is in the partial discharge state, the spectral ratio ranges under different wavelength bands are as follows: or and ; When the switchgear is in the abnormal heating state, the spectral ratio ranges under different wavelength bands are as follows: and ; Among them, is the standard spectral ratio in the ultraviolet band, is the standard spectral ratio in the infrared band.

10. A switchgear status recognition device based on spectral ratio tracking according to claim 5, characterized in that, The switchgear state recognition device further includes an alarm module and a wireless communication module. When it is detected that the spectral ratio characteristics conform to the spectral ratio characteristics in the partial discharge fault or overheating fault state, an alarm is triggered and transmitted to the host computer or the remote monitoring center through the wireless communication module.

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