CN113706840B - Partial discharge ultrahigh frequency monitoring and grading alarm circuit and alarm device and method thereof - Google Patents

Abstract

The application relates to a partial discharge UHF monitoring and grading alarm circuit and an alarm method and device thereof. The partial discharge UHF monitoring and grading alarm circuit includes a UHF signal acquisition module for collecting UHF partial discharge signals in a preset space; a UHF signal processing module, which is connected with the UHF signal acquisition module Electrically connected, used to preprocess the UHF partial discharge signal to generate a target frequency band signal; an alarm module, electrically connected to the UHF signal processing module, used to obtain the target frequency band signal according to a preset algorithm compare the maximum frequency value with at least one frequency threshold range corresponding to the alarm level, and generate an alarm signal corresponding to the alarm level according to the comparison result. The application can monitor partial discharge ultra-high frequency signals, provide hierarchical alarms, and send short messages, and has the advantages of small data volume, fast processing speed, simple hardware, low cost, and strong anti-interference.

Description

Partial discharge ultra-high frequency monitoring and classification alarm circuit and its alarm device and method

technical field

The present application relates to the technical field of equipment monitoring, in particular to a partial discharge UHF monitoring and grading alarm circuit and an alarm method and device thereof.

Background technique

There are a large number of insulators in electrical equipment, and these insulators have problems such as long-term withstand voltage or manufacturing process. When the field strength generated by the applied voltage in the electrical equipment, there will be discharges in only the insulating part of the area, but there will be no discharge in the discharge area. The phenomenon of forming fixed discharge channels is called partial discharge.

Partial discharge will lead to a vicious circle of deterioration and defects in the insulation of power equipment, and even lead to insulation accidents in severe cases. Therefore, the detection of partial discharge can avoid sudden insulation damage accidents in the operation of power equipment.

However, most of the traditional detection methods are pattern recognition methods, and pattern recognition uses certain analysis algorithms to distinguish its categories according to different characteristics or attributes of the research object. To put it simply, pattern recognition is the study of some automatic techniques, so that computing relies on this automatic technique to assign the patterns to be recognized to their own patterns. However, this method needs to collect a large amount of information data for pattern discrimination, which is difficult to process due to the large amount of data.

Contents of the invention

Based on this, it is necessary to provide a partial discharge ultra-high frequency monitoring and grading alarm circuit and an alarm method and device for the above technical problems.

In order to achieve the above purpose and other purposes, one aspect of the application provides a partial discharge UHF monitoring and grading alarm circuit, including a UHF signal acquisition module, a UHF signal processing module and an alarm module, and a UHF signal acquisition module. The module is used to collect UHF partial discharge signals in the preset space; the UHF signal processing module is electrically connected to the UHF signal acquisition module, and is used to preprocess the UHF partial discharge signals to generate Target frequency band signal; the alarm module is electrically connected to the UHF signal processing module, and is used to obtain the maximum frequency value of the target frequency band signal according to a preset algorithm, and compare the maximum frequency value with a frequency threshold corresponding to at least one alarm level Range comparison, and generate an alarm signal corresponding to the alarm level according to the comparison result.

In the partial discharge UHF monitoring and grading alarm circuit in the above embodiment, since the UHF signal is weaker during propagation and can effectively avoid interference such as on-site corona, by setting the UHF signal acquisition module, the collected The required UHF signal improves the detection sensitivity and has a strong interference ability. The collected UHF signal is transmitted to the UHF signal processing module for filtering, amplification and other processing, so that the UHF signal can meet the frequency range that the alarm module can handle, and retain some of its peak or phase characteristics, so that Achieve subsequent detection and processing capabilities for partial discharge UHF signals, optimize processing functions, and reduce the difficulty of subsequent data processing. Continue to send the preprocessed data to the alarm module, collect, record and compare with the threshold, judge whether it is within the threshold range, and send an alarm signal, so that the staff can intuitively judge the partial discharge situation immediately according to the alarm signal.

In one of the embodiments, the UHF signal acquisition module includes a UHF antenna sensor, and the UHF antenna sensor is electrically connected to the UHF signal processing module for collecting UHF signals in a preset space. Partial discharge signals for accurate acquisition of UHF signals.

In one of the embodiments, the UHF signal processing module includes a bandpass filter, a high frequency amplifier and a wave detector. A band-pass filter is electrically connected to the UHF antenna sensor for acquiring UHF signals within a preset frequency band; a high-frequency amplifier is electrically connected to the band-pass filter for controlling the UHF The signal is subjected to low-noise differential amplification to obtain a high-frequency amplified signal; the detector is electrically connected to the high-frequency amplifier, and is used to generate an envelope waveform according to the high-frequency amplified signal to follow the target frequency band where the high-frequency amplified signal changes signal, wherein the target frequency band signal is an envelope signal of the high-frequency amplified signal. Effectively filter out low-frequency information and retain some of its peak or phase characteristics, so that the UHF signal can meet the frequency range that the alarm module can handle, so as to achieve the subsequent detection and processing capabilities of partial discharge UHF signals .

In one embodiment, the order of the bandpass filter is 7; the resistance value of the detector is 19 kΩ-21 kΩ, and the capacitance value of the detector is 0.015 μF-0.025 μF. In order to effectively filter out part of the interference and extract accurate UHF signals; the speed of capacitor discharge is not less than the speed of the envelope of the input signal to meet the conditions of resistance and capacitance in the detection circuit.

In one of the embodiments, the alarm module includes a sampler and a control chip, the sampler is electrically connected to the UHF signal acquisition module, and is used to obtain a target sampling signal according to the target frequency band signal; the control chip is connected to the The sampler is electrically connected, and is used to obtain the maximum frequency value of the target sampling signal according to a preset algorithm, compare the maximum frequency value with a plurality of frequency threshold ranges corresponding to different alarm levels, and generate a frequency corresponding to the alarm level according to the comparison result. alarm signal. The pulse amplitude, quantity, phase distribution and frequency spectrum of UHF signals generated by partial discharge of different types of insulation defects are different. Therefore, by setting the control chip to collect various types of discharge data of electrical equipment, extract the maximum frequency values of various discharge types according to the preset algorithm, and analyze and extract the maximum frequency values to represent the thresholds of different discharge levels. Then compare the signal processed by the UHF signal processing module collected by the sampler with the threshold value, so that the alarm level can be quickly judged and the type of insulation defect can be judged.

In one of the embodiments, the alarm module further includes an alarm device, which is connected to the control chip and is used to execute a preset alarm action according to the alarm signal; wherein, the preset alarm action includes issuing and At least one of alarm sound, alarm light and alarm message corresponding to the alarm level. In order to facilitate the staff to timely and intuitively judge the discharge situation according to the sound, light or SMS reminder.

In one of the embodiments, the alarm signal includes a first-level alarm, a second-level alarm, and a third-level alarm for indicating that the partial discharge intensity gradually increases; the frequency threshold range includes the first frequency threshold range corresponding to the first-level alarm , the second frequency threshold range corresponding to the second-level alarm and the third frequency threshold range corresponding to the third-level alarm. In order to facilitate the staff to take corresponding measures according to the alarm level.

In one of the embodiments, the alarm device is configured to: emit a yellow alarm light according to the received first-level alarm; emit an orange alarm light according to the received second-level alarm; send out an alarm light according to the received third-level alarm Red warning light. It is convenient for the staff to judge the alarm level according to the light color, so as to know the discharge situation and take corresponding measures.

Another aspect of the application provides a partial discharge UHF monitoring and grading alarm device, including: a housing, a built-in cavity; and any partial discharge UHF monitoring and grading alarm circuit described in any embodiment of the application, at least partially located within the cavity.

In the storage device in the above embodiment, the UHF signal acquisition module can effectively collect UHF signals by setting the antenna sensing surface to collect signals, so that the partial discharge UHF monitoring and grading alarm device can effectively avoid on-site Interference such as corona. By setting the UHF signal processing module to filter and amplify the collected UHF signal, the UHF signal can meet the frequency range that the alarm module can handle, and retain some of its peak or phase characteristics, so as to achieve follow-up The ability to detect and process partial discharge ultra-high frequency signals and optimize the processing function to reduce the difficulty of subsequent data processing. By setting the alarm module to collect and record the pre-processed signal and compare it with the threshold value, the indicator lights of different colors are issued, so that the staff can intuitively judge the alarm level according to the color of the indicator light.

Another aspect of the present application provides a partial discharge UHF monitoring and grading alarm method, including: collecting UHF partial discharge signals in a preset space; preprocessing the UHF partial discharge signals to generate target frequency bands signal; obtain the maximum frequency value of the target frequency band signal according to a preset algorithm, and compare the maximum frequency value with at least one frequency threshold range corresponding to the alarm level, so as to generate an alarm signal corresponding to the alarm level according to the comparison result.

In the data storage control method in the above embodiment, the UHF partial discharge signal in the preset space is collected to facilitate data detection and effectively avoid interference such as on-site corona. By preprocessing the UHF partial discharge signal, amplify the extremely small signal collected by the UHF antenna sensor, filter the low frequency signal, and retain some of its peak or phase characteristics, so as to improve the accuracy of the data and reduce the processing data difficulty. By obtaining the maximum frequency value of the target frequency band signal according to a preset algorithm, comparing the maximum frequency value with a frequency threshold range corresponding to at least one alarm level, the alarm device judges the alarm signal according to the comparison result, thereby making a preset alarm action, so that the staff can quickly judge the discharge situation according to the alarm action.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those skilled in the art, other drawings can also be obtained based on these drawings without creative effort.

FIG. 1 is a schematic structural diagram of a partial discharge UHF monitoring and grading alarm circuit provided in the first embodiment of the present application;

2 is a schematic structural diagram of a partial discharge UHF monitoring and grading alarm circuit provided in the second embodiment of the present application;

3 is a schematic structural diagram of a partial discharge ultra-high frequency monitoring and grading alarm circuit provided in the third embodiment of the present application;

Fig. 4 is a diagram of input and output signals when the detector resistance value is 20 kΩ and the capacitance value is 0.02 μF in a partial discharge ultra-high frequency monitoring and classification alarm circuit provided in the third embodiment of the present application;

5 is a schematic structural diagram of a partial discharge UHF monitoring and grading alarm circuit provided in the fourth embodiment of the present application;

6 is a schematic structural diagram of a partial discharge UHF monitoring and grading alarm circuit provided in the fifth embodiment of the present application;

Fig. 7 is a structural schematic diagram of a partial discharge ultra-high frequency monitoring and grading alarm device in an embodiment;

Fig. 8 is a schematic flowchart of a partial discharge ultra-high frequency monitoring and grading alarm method in an embodiment.

Explanation of reference signs:

100. Partial discharge UHF monitoring and grading alarm circuit; 10. UHF signal acquisition module; 20. UHF signal processing module; 30. Alarm module; 101. UHF antenna sensor; 201. Bandpass filter; 202. High-frequency amplifier; 203. Geophone; 301. Sampler; 302. Control chip; 303. Alarm device; 200. Partial discharge UHF monitoring and grading alarm device; 1. Shell; 2. Cavity; 3. Cable; 4. Antenna sensing surface; 5. Indicator light.

Detailed ways

In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the application are given in the drawings. However, the present application can be embodied in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of this application more thorough and comprehensive.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this application belongs. The terms used herein in the specification of the application are only for the purpose of describing specific embodiments, and are not intended to limit the application.

It can be understood that the terms "first", "second" and the like used in this application may be used to describe various elements herein, but these elements are not limited by these terms. These terms are only used to distinguish one element from another element.

It should be noted that when an element is considered to be "connected" to another element, it may be directly connected to the other element, or connected to the other element through an intervening element. In addition, "connection" in the following embodiments should be understood as "electrical connection", "communication connection" and the like if there is transmission of electrical signals or data between the connected objects.

Partial discharge is a discharge phenomenon in a local area in the insulation structure of the switchgear. This discharge is due to the breakdown of the insulation in a local area, but the insulation does not have a penetrating breakdown. Timely detection of partial discharge in the switchgear will effectively avoid further damage to the insulation of the switchgear. The existing detection system collects a large amount of information and data for mode discrimination. The amount of data is large, the processing is difficult, and the accuracy is high, but it cannot meet the requirements of on-site detection and alarm. .

Based on this, please refer to FIG. 1. In one embodiment of the present application, a partial discharge UHF monitoring and classification alarm circuit 100 is provided, including a UHF signal acquisition module 10, a UHF signal processing module 20 and an alarm circuit. Module 30 , the UHF signal acquisition module 10 is electrically connected to the UHF signal processing module 20 , and the alarm module 30 is electrically connected to the UHF signal processing module 20 . Wherein the UHF signal acquisition module 10 is used to collect UHF partial discharge signals in a preset space, and the UHF signal processing module 20 is used to preprocess the UHF partial discharge signals to generate target frequency band signals, The alarm module 30 is used to obtain the maximum frequency value of the target frequency band signal according to a preset algorithm, compare the maximum frequency value with at least one frequency threshold range corresponding to the alarm level, and generate an alarm signal corresponding to the alarm level according to the comparison result .

As an example, please continue to refer to FIG. 1. Since the UHF signal has less attenuation during propagation and can effectively avoid interference such as on-site corona, the required UHF signal is collected by setting the UHF signal acquisition module 10. Therefore, the detection sensitivity is high and the interference ability is strong. Transmit the collected UHF signal to the UHF signal processing module 20 for filtering, amplification and other processing, so that the UHF signal can meet the frequency range that the alarm module 30 can handle, and retain some of its peak or phase characteristics , so as to achieve the subsequent detection and processing capabilities of partial discharge UHF signals, optimize the processing function, and reduce the difficulty of subsequent data processing. Continue to send the preprocessed data to the alarm module 30 for collection, recording and comparison with the threshold value to determine whether it is within the threshold value range and send an alarm signal so that the staff can intuitively judge the partial discharge situation immediately according to the alarm signal.

As an example, please refer to FIG. 2. In one embodiment of the present application, the UHF signal acquisition module 10 includes a UHF antenna sensor 101, which is electrically connected to the UHF signal processing module 20, and is used to collect UHF partial discharge signal. In order to accurately collect UHF signals.

As an example, please refer to FIG. 3 , in an embodiment of the present application, the UHF signal processing module 20 includes a bandpass filter 201 , a high frequency amplifier 202 and a wave detector 203 . By setting the band-pass filter 201 to filter out the low-frequency information, obtain the UHF signal within 300MHz～1000MHz; the high-frequency amplifier 202 is electrically connected with the band-pass filter 201, because the UHF antenna sensor 101 receives The partial discharge signal power is between -85dBm and -15dBm, and the sensitivity of the subsequent envelope detection circuit is not higher than -40dBm, so it is necessary to perform low-noise differential amplification on the UHF signal to obtain high-frequency amplified signals The wave detector 203 is electrically connected with the high-frequency amplifier 202, and is used to generate the target frequency band signal whose envelope waveform follows the change of the high-frequency amplified signal according to the high-frequency amplified signal, and effectively retains part of its peak value or phase, etc. feature, so that the ultra-high frequency signal can meet the frequency range that the alarm module 30 can handle, so as to achieve the subsequent detection and processing capabilities of the partial discharge ultra-high frequency signal.

Specifically, in the partial discharge UHF monitoring and grading alarm circuit 100 in the above embodiment, please continue to refer to FIG. 3 , the high-frequency amplifier 202 selects ZKL-1R5, each of which has good performance, and uses differential amplification, common mode The rejection ratio is high, and the gain is 40dB, so as to amplify the partial discharge signal. The band-pass filter 201 is designed based on the Chebyshev I-type filter. Since the magnitude response of the Chebyshev I-type filter is equiripple in the passband and monotonous in the stopband, the simulation structure shows that part of the interference can be effectively filtered out. The extracted UHF signal can meet the design requirements. The design steps are: Step 1, measure the signal characteristics of partial discharge according to the UHF detection method, at first determine the bandwidth, the lower cut-off frequency fl=300MHz of the frequency band, the lower stop band frequency fls=240MHz; the upper cut-off frequency fh=1500MHz, the upper stop frequency Band frequency fhs=300MHz; center frequency f0=900MHz, bandwidth BW=1200MHz. Then determine the minimum attenuation of the stop band, take its value As=30dB; take the value of the passband ripple as δ=0.5dB, then the parameter ε=0.023 about the passband ripple, and the larger the ε, the larger the ripple, 0<ε <1; step 2, and then obtain the applicable order n of the Chebyshev I type filter through the passband corner frequency ω_0, the stopband start frequency ω_s, the passband ripple δ and the stopband minimum attenuation A_S. The order of the bandpass filter 201 is finally determined to be 7th order, which can meet the design requirements. The detector 203 needs to select appropriate RC parameters to meet the requirements of no distortion and maximum relative error of the peak value, that is, the output envelope waveform follows the change of the input signal, and the envelope is the curve of the amplitude of the random process changing with time. The design steps of the wave detector 203 are as follows: Step 1. Take R as a fixed value of 10kΩ, and change the value of C. Take C=0.002μF, 0.02μF, and 0.1μF. The input and output waveforms are detected by the oscilloscope. It can be obtained by observation that when C =0.02μF, the waveform of the output signal is the envelope detection of the input signal, and the waveform of the output voltage has been closely following the change of the envelope of the input signal; step 2, take the C value as a fixed value of 0.02μF, and change the R value , take R=1kΩ, 20kΩ, 50kΩ, and obtain the input and output by the oscilloscope, which can be obtained from observation. When taking R=20kΩ, the output signal is the envelope signal of the input signal; step 3, from the above simulation experiment can be obtained: when When R=20kΩ, C=0.02μF, the discharge speed of capacitor C is not less than the speed of falling of the input signal envelope, which meets the conditions of R and C in the detection circuit. The waveform is shown in Figure 4. Therefore, the resistance value of the detector 203 is 19 kΩ-21 kΩ, and the capacitance value of the detector 203 is 0.015 μF-0.025 μF.

As an example, please refer to FIG. 5 . In one embodiment of the present application, the alarm module 3030 includes a sampler 301 and a control chip 302 . The sampler 301 is electrically connected to the UHF signal acquisition module 10, and is used to obtain the target sampling signal according to the target frequency band signal; the control chip 302 is electrically connected to the sampler 301, and is used to obtain the target sampling signal according to a preset algorithm. A maximum frequency value, comparing the maximum frequency value with frequency threshold ranges corresponding to multiple different alarm levels, and generating an alarm signal corresponding to the alarm level according to the comparison result. The pulse amplitude, quantity, phase distribution and frequency spectrum of UHF signals generated by partial discharge of different types of insulation defects are different. Therefore, by setting the control chip 302 to collect various types of discharge data of electrical equipment, extract each maximum frequency value of each discharge type according to a preset algorithm, and analyze and extract each maximum frequency value to represent the threshold value of different discharge levels. Then compare the signal processed by the UHF signal processing module 20 collected by the sampler 301 with the threshold value, so as to quickly determine the alarm level and the type of insulation defect.

Specifically, in the partial discharge UHF monitoring and grading alarm circuit 100 in the above-mentioned embodiment, please continue to refer to FIG. The maximum value of the frequency point, analyzing and extracting the maximum value of each frequency point to obtain thresholds that can characterize different discharge levels, such as the first frequency threshold, the second frequency threshold, and the third frequency threshold. The FFT algorithm is a fast algorithm for discrete Fourier transform. It can transform a signal into the frequency domain and extract the spectrum of a signal. It is difficult to see the characteristics of some signals in the time domain, but if they are transformed into the frequency domain , it is easy to see the characteristics. Therefore, FFT is used here. First, an oscilloscope is used to collect UHF single-shot waveforms under different discharge types in the preset space, and then the collected data group is extracted in the host computer according to the FFT algorithm. The maximum value of each frequency point in various discharge types, Finally, the maximum values of various discharge types at each frequency point are analyzed by the mean value algorithm, and the corresponding average values are used to characterize the parameters of different discharge levels: the first frequency threshold, the second frequency threshold, and the third frequency threshold.

As an example, please refer to FIG. 6. In one embodiment of the present application, the alarm device 303 is connected to the control chip 302, and is used to execute a preset alarm action according to the alarm signal; wherein, the preset alarm action includes sending and alarm level At least one of the corresponding alarm sound, alarm light and alarm text message, so that the staff can timely and intuitively judge the discharge situation according to the sound, light or text message reminder.

Further, in one embodiment of the present application, the alarm signal includes a first-level alarm, a second-level alarm, and a third-level alarm for indicating that the partial discharge intensity gradually increases; the frequency threshold range includes the first frequency threshold corresponding to the first-level alarm range, a second frequency threshold range for a second-level alarm, and a third frequency threshold range for a third-level alarm. It emits yellow alarm light according to the received first-level alarm; emits orange alarm light according to the received second-level alarm; emits red alarm light according to the received third-level alarm. It should be noted that, in other embodiments, one siren sound may be sounded according to the received first-level alarm; two siren sounds may be sounded according to the received second-level alarm; three siren sounds may be sounded according to the received third-level alarm. Or send the corresponding first-level, second-level, and third-level SMS to the mobile phone or computer according to the first-level alarm, second-level alarm, and third-level alarm.

As an example, please refer to FIG. 7. In one embodiment of the present application, a partial discharge ultra-high frequency monitoring and grading alarm device 200 is provided, including a housing 1, a built-in cavity 2 and any of the embodiments of the present application. The partial discharge UHF monitoring and grading alarm circuit 100 described above. By setting the antenna sensing surface 4 to collect signals, the UHF signal acquisition module 10 can effectively collect UHF signals, so that the partial discharge UHF monitoring and grading alarm device can effectively avoid interference such as on-site corona. By setting the ultra-high frequency signal processing module 20, the collected ultra-high frequency signal is processed by filtering, amplifying, etc., so that the ultra-high frequency signal can meet the frequency range that the alarm module 30 can handle, and retain its partial peak or phase characteristics, thereby Achieve subsequent detection and processing capabilities for partial discharge UHF signals, optimize processing functions, and reduce the difficulty of subsequent data processing. By setting the alarm module 30 to collect and record the pre-processed signal and compare it with the threshold value, the indicator lights 5 of different colors are issued, so that the staff can intuitively judge the alarm level according to the color of the indicator lights 5 .

As an example, please refer to FIG. 8. In one embodiment of the present application, a partial discharge UHF monitoring and grading alarm method is provided, which is applied to a partial discharge UHF monitoring and grading alarm circuit 100. The method includes:

Step S10: collecting UHF partial discharge signals in a preset space;

Step S20: Preprocessing the UHF partial discharge signal to generate a target frequency band signal;

Step S30: Acquire the maximum frequency value of the target frequency band signal according to a preset algorithm, compare the maximum frequency value with at least one frequency threshold range corresponding to the alarm level, and generate an alarm signal corresponding to the alarm level according to the comparison result.

Specifically, due to the small attenuation of the UHF electromagnetic wave signal generated by the partial discharge of electrical equipment during propagation, the electromagnetic wave is reflected at discontinuities such as insulators in the equipment, and will also cause resonance in the equipment cavity, prolonging the oscillation time of the partial discharge signal Corona discharge interference between high-voltage lines and equipment in the air is the most common interference on site. The frequency of electromagnetic waves generated by the discharge is mainly below 200MHz, and the frequency band of UHF signals is usually 300M~3000MHz. Therefore, by collecting UHF partial discharge signals in the preset space, data detection is facilitated and interference such as on-site corona is effectively avoided. Since the acquisition signals of the UHF acquisition module 10 are extremely small signals at the millivolt level, the signal amplitude acquired by the UHF antenna sensor 101 needs to be amplified by the high frequency amplifier 202; There are still some low-frequency signals at 3000MHz. In order to reduce the amount of data, the bandpass filter 201 needs to be used to filter the signals; in order to quickly and conveniently process the data of the sampler 301, the wave detector 203 needs to be used to retain some of its peak or phase characteristics. Therefore, the UHF partial discharge signal is preprocessed by the UHF signal processing module 20 so that the UHF signal can meet the frequency range that the alarm module 30 can process. In order to enable the staff to intuitively and quickly judge different discharge situations according to the alarm signal, the ultra-high frequency single-shot waveform under various discharge types in the equipment is collected, and the maximum value of each frequency point is extracted through a preset algorithm, and represented as different threshold ranges. According to the gradual increase of partial discharge intensity, it is set as the first-level alarm threshold range, the second-level alarm threshold range and the third-level alarm threshold range. Then compare the collected UHF signal with the frequency threshold range corresponding to at least one alarm level according to the preset algorithm, and make a preset alarm action according to the received alarm. The preset alarm action includes sending out an alarm sound corresponding to the alarm level , alarm light and alarm message at least one. The alarm signal, for example, emits a yellow alarm light according to the received first-level alarm; emits an orange alarm light according to the received second-level alarm; and emits a red alarm light according to the received third-level alarm. Or sound one siren upon receipt of a first-level alarm; two sirens upon receipt of a second-level alarm; three sirens upon receipt of a third-level alarm. Or send the corresponding first-level, second-level, and third-level SMS to the mobile phone or computer according to the first-level alarm, second-level alarm, and third-level alarm.

In the description of this specification, descriptions referring to the terms "some embodiments", "other embodiments", "ideal embodiments" and the like mean that specific features, structures, materials, or characteristics described in connection with the embodiments or examples are included in this specification. In at least one embodiment or example of the invention. In this specification, schematic descriptions of the above terms do not necessarily refer to the same embodiment or example.

The technical features of the above embodiments can be combined arbitrarily. To make the description concise, all possible combinations of the technical features in the above embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, they should be It is considered to be within the range described in this specification.

The above-mentioned embodiments only represent several implementation modes of the present application, and the description thereof is relatively specific and detailed, but it should not be construed as limiting the scope of the patent for the invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the scope of protection of the patent application should be based on the appended claims.

Claims (9)

1. The utility model provides a partial discharge superfrequency monitoring hierarchical alarm circuit which characterized in that includes:

the ultrahigh frequency signal acquisition module is used for acquiring an ultrahigh frequency partial discharge signal in a preset space;

the ultrahigh frequency signal processing module is electrically connected with the ultrahigh frequency signal acquisition module and is used for preprocessing the ultrahigh frequency partial discharge signal to generate a target frequency band signal;

the alarm module is electrically connected with the ultrahigh frequency signal processing module and is used for acquiring a maximum frequency value of the target frequency band signal according to a preset algorithm, comparing the maximum frequency value with a frequency threshold range corresponding to at least one alarm level, and generating an alarm signal corresponding to the alarm level according to a comparison result, wherein the frequency threshold range is generated by the alarm module according to the ultrahigh frequency partial discharge signal acquired by history;

wherein, the ultrahigh frequency signal processing module includes:

the band-pass filter is electrically connected with the ultrahigh frequency signal acquisition module and is used for acquiring an ultrahigh frequency signal in a preset frequency band;

the high-frequency amplifier is electrically connected with the band-pass filter and is used for carrying out low-noise differential amplification on the ultrahigh-frequency signal so as to obtain a high-frequency amplified signal;

the detector is electrically connected with the high-frequency amplifier and is used for generating a target frequency band signal with an envelope waveform changing along with the high-frequency amplified signal according to the high-frequency amplified signal, wherein the target frequency band signal is the envelope signal of the high-frequency amplified signal;

the alarm module comprises:

the sampler is electrically connected with the ultrahigh frequency signal acquisition module and is used for acquiring a target sampling signal according to the target frequency band signal;

the control chip is electrically connected with the sampler and is used for acquiring the maximum frequency value of the target sampling signal according to a preset algorithm, comparing the maximum frequency value with frequency threshold ranges corresponding to a plurality of different alarm levels and generating an alarm signal corresponding to the alarm level according to the comparison result.

2. The alarm circuit of claim 1, wherein the uhf signal acquisition module comprises:

and the ultrahigh frequency antenna sensor is electrically connected with the ultrahigh frequency signal processing module and is used for acquiring an ultrahigh frequency partial discharge signal in a preset space.

3. The alarm circuit of claim 1, wherein the uhf signal has a frequency of 300MHz to 1000MHz.

4. An alarm circuit according to claim 3, wherein the bandpass filter has an order of 7; the resistance value of the detector is 19k omega-21 k omega, and the capacitance value of the detector is 0.015 mu F-0.025 mu F.

5. The alarm circuit of claim 1, wherein the alarm module further comprises:

the alarm device is connected with the control chip and used for executing preset alarm actions according to the alarm signals;

the preset alarm action comprises at least one of alarm sound, alarm light and alarm short message corresponding to the alarm level.

6. The alarm circuit of claim 5, wherein the alarm signal comprises a primary alarm, a secondary alarm, and a tertiary alarm for indicating a gradual increase in partial discharge intensity;

the frequency threshold ranges include a first frequency threshold range corresponding to a primary alarm, a second frequency threshold range corresponding to a secondary alarm, and a third frequency threshold range corresponding to a tertiary alarm.

7. The alarm circuit of claim 6, wherein the alarm device is configured to:

sending out yellow alarm light according to the received primary alarm;

sending out orange alarm light according to the received secondary alarm;

and sending out red alarm light according to the received three-level alarm.

8. The utility model provides a partial discharge superfrequency monitoring hierarchical alarm device which characterized in that includes:

a housing having a cavity therein;

and the partial discharge ultrahigh frequency monitoring and classifying alarm circuit as claimed in any one of claims 1 to 7, at least partially located in the cavity.

9. The partial discharge ultrahigh frequency monitoring and grading alarm method is characterized by comprising the following steps of:

collecting an ultrahigh frequency partial discharge signal in a preset space;

obtaining an ultrahigh frequency signal in a preset frequency band, and performing low-noise differential amplification on the ultrahigh frequency signal to obtain a high-frequency amplified signal, and generating a target frequency band signal with an envelope waveform changing along with the high-frequency amplified signal according to the high-frequency amplified signal, wherein the target frequency band signal is an envelope signal of the high-frequency amplified signal;

acquiring a target sampling signal according to the target frequency band signal, acquiring a maximum frequency value of the target sampling signal according to a preset algorithm, and comparing the maximum frequency value with frequency threshold ranges corresponding to a plurality of different alarm levels to generate an alarm signal corresponding to the alarm level according to a comparison result; the frequency threshold range is generated by the alarm module according to the ultrahigh frequency partial discharge signals collected by the history.