A device for detecting partial discharge of electrical equipment by capturing sound pressure of noise points

Abstract

The present invention provides an electrical equipment partial discharge troubleshooting device for capturing the sound pressure of noise points, and belongs to the technical field of inspection of distribution networks and outdoor substations. An electrical equipment partial discharge troubleshooting device for capturing the sound pressure of noise points, comprising a noise capture system, a data processing end connected to the noise capture system, the noise capture system comprising a pan-tilt base, a sound pressure acquisition module, the data processing end comprising a multi-channel audio acquisition card, a processing terminal, a key input module and a display module, an audio conversion unit, a mixing processing unit, an electric scanning program control unit, a signal processing control unit, and a feedback output unit built into the processing terminal. On the basis of the original equipment, the design of the monitoring structure is optimized, a dynamic noise capture system is constructed, and the attenuation recognition method is adopted to realize the disassembly and differentiation of audio data, thereby improving the recognition and positioning accuracy.

Description

Technical Field

[0001] The invention belongs to the technical field of inspection of distribution networks and outdoor substations, and in particular relates to a device for troubleshooting partial discharge of electrical equipment for capturing sound pressure of noise points. Background Art

[0002] At present, a large number of electrical equipment in the power system are arranged compactly and concentratedly, and the insulation margin is getting smaller and smaller. Especially when the air pollution is serious and the humidity is high, the electrical equipment operating in such an environment will have surface discharge in the local area of ​​the insulator, which will cause the serious consequences of reduced insulation life and damage to the power equipment, affecting production safety. In order to prevent the above situation, the power department conducts regular inspections on the installed circuits and power equipment.

[0003] The substation is an environment with multiple noises. When certain equipment failures occur, some abnormal sounds will be emitted, which will be mixed with the environmental noise. If these abnormal sounds can be accurately located, the faulty equipment can be accurately identified, thereby eliminating the fault and reducing the loss caused by equipment failure to the substation.

[0004] When local discharge occurs in high-voltage electrical equipment, the gas or liquid on the insulating surface breaks down and generates ultrasonic energy that radiates in all directions. Therefore, the ultrasonic detection method can be used, that is, the sound waves generated in the discharge can be detected by the sound pressure sensor to determine the location of the local discharge point. However, traditional sound pressure sensors can only achieve a fuzzy positioning mode in a small area and cannot accurately locate the local discharge location.

[0005] Utility model CN206193169U discloses an accurate directional local discharge ultrasonic array sensor for detecting local discharge of electrical equipment for capturing sound pressure of noise points, including a housing, a small motor, a reducer, a coupling, a piezoelectric plate, a spiral structure, an array plate and an ultrasonic array sensor element. The device drives the spiral structure through the forward and reverse rotation of the motor to make the array plate reciprocate and cyclically rotate, thereby performing scanning detection. However, the device has many mechanical structures, is relatively complex, and is inconvenient to use.

[0006] The invention with patent number CN102360059A discloses an online detection method and device for local faults of power transmission and distribution lines of electrical equipment local discharge troubleshooting device that captures sound pressure of noise points. The invention adopts an online remote directional focusing pickup / positioning method to capture the ultrasonic signal generated during the discharge process, and uses heterodyne method to convert the picked-up ultrasonic signal into an acoustic / electrical signal that can be recognized by the detection personnel. According to the numerical value or change of sound pressure / voltage, it is qualitatively and quantitatively judged whether there is a dirty discharge phenomenon in the part prone to local discharge faults, and the strength of the dirty discharge, thereby judging the strength of the dirty discharge at the legal position of the discharge fault and the size of the threat to the system, which can greatly reduce the use of labor and fixed inspection costs, reduce the previous power outage workload, and effectively ensure the safe operation of power equipment. However, the invention can only use a fixed-point detection method, and cannot comprehensively check the existence of local discharge parts. In addition, the installation environment of outdoor electrical equipment is relatively harsh, and it is inevitable to be interfered by noise signals when receiving data.

[0007] At present, the noise location instruments widely used in substations use one-dimensional linear arrays or two-dimensional arrays to collect noise. The one-dimensional array has great limitations in picking up the direction information of the sound field and has low accuracy. The two-dimensional array is affected by the incident direction and has large errors when measuring distance. There are factors such as low sensitivity of the microphone, slow system operation speed, and low efficiency. It cannot meet the requirements of actual work and brings great trouble to maintenance work. At present, there are no more advanced alternative products on the market. In order to solve this problem, it is urgent to develop a more advanced, accurate, and efficient electrical equipment monitoring system based on sound pressure sensor arrays to accurately locate noise. Summary of the invention

[0008] The technical problem to be solved by the present invention is to provide an electrical equipment partial discharge detection device for capturing, monitoring, distinguishing and identifying noise points and capturing the sound pressure of noise points in view of the deficiencies in the prior art.

[0009] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0010] A device for detecting partial discharge of electrical equipment for capturing sound pressure of noise points comprises a noise capturing system, a data processing end connected to the noise capturing system,

[0011] The noise capture system includes a pan-tilt base and a sound pressure collection module arranged on the pan-tilt base.

[0012] The data processing end includes a multi-channel audio acquisition card connected to the sound pressure acquisition module, a processing terminal connected to the multi-channel audio acquisition card, a key input module and a display module connected to the processing terminal,

[0013] The audio conversion unit, mixing processing unit, electronic scanning program control unit, signal processing control unit, and feedback output unit built into the processing terminal,

[0014] The electric scanning program control unit is connected to the pan / tilt base and the key input module respectively;

[0015] The audio conversion unit converts the precisely timed audio signal read by the processing terminal from the multi-channel audio acquisition card into audio data with inserted timing annotations, and the electronic scanning program control unit inputs the spatial coordinate parameters of the sound pressure sensor in the sound pressure acquisition module into the audio conversion unit, and the audio conversion unit inserts the corresponding spatial coordinates into the audio data received from the sound pressure sensors set at different time node positions.

[0016] The gimbal base includes a three-axis gimbal base, a 3-in-1 spherical gimbal base, and a dual-axis tracking rotating gimbal base. The sound pressure acquisition module includes an equipment mounting frame, and a sound pressure sensor arranged on the equipment mounting frame. The sound pressure sensor includes a capacitive electret microphone and a noise sensor. The equipment mounting frame is a three-dimensional structural frame fixed on the mounting end of the gimbal base. The three-dimensional structural frame includes a regular triangular pyramid frame, a circular ring frame, an axisymmetric or array frame. The sound pressure sensors are arranged on the three-dimensional structural frame at equal intervals.

[0017] The multi-channel audio acquisition card is respectively connected to the corresponding sound pressure sensors arranged in the sound pressure acquisition module, and is used for synchronous acquisition of the audio signal detected by the sound pressure sensor; the multi-channel audio acquisition card is connected to a high-precision electronic clock to achieve accurate timing of the audio signal, and the multi-channel audio acquisition card includes an analog-to-digital converter connected to the sound pressure sensor in a one-to-one correspondence, and an adapter connected to the analog-to-digital converter.

[0018] The processing terminal includes a server and a high-performance computer, the key input module includes a keyboard and a handwriting board, and the display module includes a display screen and a projector.

[0019] The data transmission line arranged on the processing terminal is connected to the pan-tilt base; the electric scanning program control unit is connected to the attitude control system in the pan-tilt base through the data transmission line, and realizes the change and regulation of various parameters in the attitude control system to achieve precise control of the relative spatial attitude of the sound pressure collection module arranged on the pan-tilt base; the keyboard realizes the input of relevant parameters in the electric scanning program control unit.

[0020] The electronic scanning program control unit realizes the reading of audio data under different time node parameter models by controlling the operating state of the pan-tilt base. The mixing processing unit includes an ultrasonic array data model and a correction instruction output terminal. The ultrasonic array data model includes a wave direction of arrival algorithm, an array structure, an array signal processing algorithm, and an audio splitting unit. The wave direction of arrival algorithm realizes the positioning of the direction of the audio. The array structure is the structure and spatial layout parameters of the equipment mounting frame and the sound pressure sensor in the sound pressure acquisition module. The array signal processing algorithm is a model parameter method based on AML. The audio splitting unit performs the processing of the parameters of the different time nodes. The relevant values ​​of inconsistent audio data attenuation under the time node parameter model are decomposed according to the relative energy attenuation ratio of frequency, hertz, timbre, periodic or regular amplitude. The ultrasonic array data model combines the different postures of the pan-tilt base in the different time node parameter models and the relative energy attenuation ratios of different frequencies, hertz, timbre, periodic or regular amplitudes in the audio to achieve the distinction, disassembly and positioning of the audio data; the correction instruction output end is connected to the electric scanning program control unit. When the data read by the ultrasonic array data model is incomplete, the correction instruction output end issues an instruction to the electric scanning program control unit to reset the motion trajectory.

[0021] The signal processing control unit identifies, classifies and outputs the disassembled, differentiated and located audio data according to the characteristics of the noise points.

[0022] The feedback output unit converts the audio data output by the signal processing control unit into a video signal or a distance parameter and sends the result to the display module.

[0023] Furthermore, the traditional substation or electrical equipment has a simple structure and no barriers, which is conducive to the linear propagation of sound noise, that is, the direction of the sound source is the direction of the noise. At the same time, the noise generated by the electrical equipment itself during operation is small or the noise frequency and energy level are relatively stable, making it easy to distinguish the environmental background noise, the electrical equipment operation noise and the noise of the local discharge of the electrical equipment.

[0024] Furthermore, the traditional electrical equipment has a simple internal structure, a relatively single voltage level, and is easy to operate during maintenance. It does not involve the coordination between electrical units of multiple voltage levels, the insulation design is relatively uniform, and the internal design of the traditional electrical equipment has a relatively ample partial discharge safety gap.

[0025] Furthermore, based on the rapid development of intelligent and automated electrical equipment, the voltage difference between the operating part and the monitoring part and the control part of the electrical equipment has gradually widened. Combined with the fact that the voltage safety level of commonly used electrical equipment is mostly 220 volts. In a strong electromagnetic environment, high-potential equipment can easily cause discharge interference or damage to lower-potential equipment, forming discharge noise. In order to effectively and quickly troubleshoot discharge noise, a noise capture and troubleshooting device is designed to quickly detect, decompose, and identify discharge noise while ensuring uninterrupted operation.

[0026] Furthermore, at present, in the power industry, noise locating instruments have also been widely used in substations and other work areas. However, the noise locators currently used mostly use one-dimensional linear arrays or two-dimensional arrays to collect noise. The one-dimensional array has great limitations in picking up the direction information of the sound field and has relatively low accuracy. The two-dimensional array is affected by the incident direction and has large errors when measuring distance. There are factors such as low sensitivity of the microphone, slow system operation speed, and low efficiency.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] Furthermore, a sound pressure acquisition module with a three-dimensional structure is used to expand the differences between audio data, making it easier to locate and identify noise points.

[0029] Furthermore, the pan-tilt base is used as a motion platform to avoid the difficulty in locating the noise point due to the obstruction being located exactly between the noise point occurrence location and the noise capture system.

[0030] Furthermore, a multi-channel audio acquisition card is used to independently transmit the audio data captured by the sound pressure sensor, avoiding the reduction in positioning accuracy caused by audio compression distortion during the traditional combined transmission process, or channel congestion of a single transmission line. A high-precision electronic clock is set for time synchronization to facilitate the accurate division of audio data into time periods.

[0031] Furthermore, a pan-tilt base is provided to realize precise control of the spatial motion trajectory of the sound pressure acquisition module, so as to facilitate the detection and reading of data under parameter models at different time nodes.

[0032] Furthermore, the electronic scanning program control unit controls the motion posture of the pan-tilt base. The audio conversion unit converts the audio signal of precise timing into audio data with timing annotations and spatial coordinates, which is convenient for the mixing processing unit to identify. Based on the feature data recognition and energy level attenuation classification of the relevant audio data, the mixing processing unit adopts a combination of the wave arrival direction algorithm and the array signal processing algorithm to achieve the distinction, disassembly and positioning of the audio data.

[0033] Furthermore, the signal processing control unit screens the discharge noise points and outputs the relevant parameters according to the disassembled audio data. The feedback output unit converts the relevant parameters of the screened discharge noise points into readable data. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0035] Figure 1 : Operation principle diagram of the present invention. DETAILED DESCRIPTION

[0036] In order to better understand the present invention, the content of the present invention is further clearly described below in conjunction with the embodiments and the accompanying drawings, but the protection content of the present invention is not limited to the following embodiments. In the following description, a large number of specific details are provided to provide a more thorough understanding of the present invention. However, it is obvious to those skilled in the art that the present invention can be implemented without one or more of these details. Example

[0037] like Figure 1 As shown, this embodiment provides an electrical equipment partial discharge troubleshooting device for capturing sound pressure of noise points, including a noise capture system, a data processing end connected to the noise capture system,

[0038] The noise capture system includes a pan-tilt base and a sound pressure collection module arranged on the pan-tilt base.

[0039] The data processing end includes a multi-channel audio acquisition card connected to the sound pressure acquisition module, a processing terminal connected to the multi-channel audio acquisition card, a key input module and a display module connected to the processing terminal,

[0040] The audio conversion unit, mixing processing unit, electronic scanning program control unit, signal processing control unit, and feedback output unit built into the processing terminal,

[0041] The electric scanning program control unit is connected to the pan / tilt base and the key input module respectively.

[0042] The gimbal base includes a three-axis gimbal, a 3-in-1 spherical gimbal, and a dual-axis tracking rotating gimbal. The sound pressure acquisition module includes an equipment mounting frame, and a sound pressure sensor arranged on the equipment mounting frame. The sound pressure sensor includes a capacitive electret microphone and a noise sensor. The equipment mounting frame is a three-dimensional structural frame fixed at the mounting end on the gimbal base. The three-dimensional structural frame includes a regular triangular pyramid frame, a circular ring frame, an axisymmetric or array frame. The sound pressure sensors are arranged at equal intervals on the three-dimensional structural frame.

[0043] The multi-channel audio acquisition card is respectively connected to the corresponding sound pressure sensors arranged in the sound pressure acquisition module, and is used for synchronous acquisition of the audio signal detected by the sound pressure sensor; the multi-channel audio acquisition card is connected to a high-precision electronic clock to achieve accurate timing of the audio signal, and the multi-channel audio acquisition card includes an analog-to-digital converter connected to the sound pressure sensor in a one-to-one correspondence, and an adapter connected to the analog-to-digital converter.

[0044] The processing terminal includes a server and a high-performance computer, the key input module includes a keyboard and a handwriting board, and the display module includes a display screen and a projector.

[0045] The data transmission line arranged on the processing terminal is connected to the pan-tilt base; the electric scanning program control unit is connected to the attitude control system in the pan-tilt base through the data transmission line, and realizes the change and regulation of various parameters in the attitude control system to achieve precise control of the relative spatial attitude of the sound pressure collection module arranged on the pan-tilt base; the keyboard realizes the input of relevant parameters in the electric scanning program control unit.

[0046] The audio conversion unit converts the audio signal with precise timing read by the processing terminal from the multi-channel audio acquisition card into audio data with inserted timing annotations, and the electronic scanning program control unit inputs the spatial coordinate parameters of the sound pressure sensor in the sound pressure acquisition module into the audio conversion unit, and the audio conversion unit inserts the corresponding spatial coordinates into the audio data received from the sound pressure sensor set at different time node positions.

[0047] The electronic scanning program control unit realizes the reading of audio data under different time node parameter models by controlling the operating state of the pan-tilt base. The mixing processing unit includes an ultrasonic array data model and a correction instruction output terminal. The ultrasonic array data model includes a wave direction of arrival algorithm, an array structure, an array signal processing algorithm, and an audio splitting unit. The wave direction of arrival algorithm realizes the positioning of the direction of the audio. The array structure is the structure and spatial layout parameters of the equipment mounting frame and the sound pressure sensor in the sound pressure acquisition module. The array signal processing algorithm is a model parameter method based on AML. The audio splitting unit performs the processing of the parameters of the different time nodes. The relevant values ​​of inconsistent audio data attenuation under the time node parameter model are decomposed according to the relative energy attenuation ratio of frequency, hertz, timbre, periodic or regular amplitude. The ultrasonic array data model combines the different postures of the pan-tilt base in the different time node parameter models and the relative energy attenuation ratios of different frequencies, hertz, timbre, periodic or regular amplitudes in the audio to achieve the distinction, disassembly and positioning of the audio data; the correction instruction output end is connected to the electric scanning program control unit. When the data read by the ultrasonic array data model is incomplete, the correction instruction output end issues an instruction to the electric scanning program control unit to reset the motion trajectory.

[0048] The signal processing control unit identifies, classifies and outputs the disassembled, differentiated and located audio data according to the characteristics of the noise points.

[0049] The feedback output unit converts the audio data output by the signal processing control unit into a video signal or a distance parameter and sends the result to the display module.

[0050] The adapter is connected to the high-precision electronic clock.

[0051] The different time node parameter models are position parameters of the sound pressure sensor set on the equipment mounting frame under the premise that the pan / tilt base is in different positions.

[0052] The adapter includes a 3.5mm audio data cable to Type-C and an audio data cable to USB port. The three-dimensional structure frame has built-in sound insulation cotton. Based on the premise that the audio and energy levels between the discharge noise point and the ambient noise are not exactly the same, the sound insulation cotton is set to achieve rapid screening of the discharge noise point.

[0053] The timing is to update and send out time parameters every certain time interval.

[0054] The timing annotation is to insert a new time parameter into the audio data field at a certain interval.

[0055] The audio conversion unit is connected to the electric scanning program control unit.

[0056] The relative spatial posture parameters in the electronic scanning program control unit are sent to the audio conversion unit.

[0057] When operating, the key input module can be manipulated as needed to control the spatial motion position and trajectory of the pan-tilt base through the electric scanning programmable control unit, so as to achieve positioning and movement of different relative positions under different time node parameter model conditions.

[0058] When monitoring and reading audio data, the sound pressure sensor installed on the equipment mounting bracket will read the audio information and send it to the multi-channel audio acquisition card, convert the audio signal into a digital signal and use a high-precision electronic clock to accurately time it, thereby completing the capture of the audio signal.

[0059] The audio conversion unit converts the precisely timed audio signal into audio data in a readable format with timing annotations, and merges the audio data with the spatial coordinates of the sound pressure sensor when reading the audio data. The ultrasonic array data model realizes the decomposition, differentiation and positioning of the audio data, splits the audio data into related parameters of several independent sound sources, and combines the noise reduction settings to realize the determination of the attenuation of the audio parameter energy level. Based on the array structure layout of the sound pressure sensor in the equipment mounting frame, combined with the wave arrival direction algorithm and the array signal processing algorithm, the time domain array signal is converted into a frequency domain signal through discrete Fourier transform DTF based on the AML algorithm to realize the positioning of the spatial domain parameters and audio.

[0060] The relevant parameters of the split independent sound sources are imported into the signal processing control unit for retrieval and comparison. On the basis of filtering out the background environmental noise that persists for a long time and the operation sound of electrical equipment with relatively stable audio parameters that change regularly or periodically, the relevant parameters of high-Hz, short-duration noise sound are output. The parameters meet the audio characteristics of the discharge noise during partial discharge of electrical equipment. The feedback output unit transcodes the output parameters into a readable mode for the display module to realize the display of the final result.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Other modifications or equivalent substitutions made to the technical solution of the present invention by ordinary technicians in the field should be included in the scope of the claims of the present invention as long as they do not depart from the spirit and scope of the technical solution of the present invention.

Claims

1. A device for detecting partial discharge of electrical equipment by capturing the sound pressure of noise points, characterized in that: It includes a noise capture system, the noise capture system is connected to a data processing terminal, The noise capture system includes a pan-tilt base and a sound pressure collection module arranged on the pan-tilt base. The data processing end includes a multi-channel audio acquisition card connected to the sound pressure acquisition module, a processing terminal connected to the multi-channel audio acquisition card, a key input module and a display module connected to the processing terminal, The audio conversion unit, mixing processing unit, electronic scanning program control unit, signal processing control unit, and feedback output unit built into the processing terminal, The electric scanning program control unit is connected to the pan / tilt base and the key input module respectively; The audio conversion unit converts the precisely timed audio signal read by the processing terminal from the multi-channel audio acquisition card into audio data with inserted timing annotations, and the electronic scanning program control unit inputs the spatial coordinate parameters of the sound pressure sensor in the sound pressure acquisition module into the audio conversion unit, and the audio conversion unit inserts the corresponding spatial coordinates into the audio data received from the sound pressure sensors set at different time node positions.

2. The device for detecting partial discharge of electrical equipment for capturing sound pressure of noise points according to claim 1, characterized in that: The gimbal base includes a three-axis gimbal base, a 3-in-1 spherical gimbal base, and a dual-axis tracking rotating gimbal base. The sound pressure acquisition module includes an equipment mounting frame, and a sound pressure sensor arranged on the equipment mounting frame. The sound pressure sensor includes a capacitive electret microphone and a noise sensor. The equipment mounting frame is a three-dimensional structural frame fixed on the mounting end of the gimbal base. The three-dimensional structural frame includes a regular triangular pyramid frame, a circular ring frame, an axisymmetric or array frame. The sound pressure sensors are arranged on the three-dimensional structural frame at equal intervals.

3. The device for detecting partial discharge of electrical equipment by capturing sound pressure of noise points according to claim 2, characterized in that: The multi-channel audio acquisition card is respectively connected to the corresponding sound pressure sensors arranged in the sound pressure acquisition module, and is used for synchronous acquisition of the audio signal detected by the sound pressure sensor; the multi-channel audio acquisition card is connected to a high-precision electronic clock to achieve accurate timing of the audio signal, and the multi-channel audio acquisition card includes an analog-to-digital converter connected to the sound pressure sensor in a one-to-one correspondence, and an adapter connected to the analog-to-digital converter.

4. The device for detecting partial discharge of electrical equipment for capturing sound pressure of noise points according to claim 3, characterized in that: The processing terminal includes a server and a high-performance computer, the key input module includes a keyboard and a handwriting board, and the display module includes a display screen and a projector.

5. The device for detecting partial discharge of electrical equipment for capturing sound pressure of noise points according to claim 4, characterized in that: The data transmission line arranged on the processing terminal is connected to the pan-tilt base; the electric scanning program control unit is connected to the attitude control system in the pan-tilt base through the data transmission line, and realizes the change and regulation of various parameters in the attitude control system to achieve precise control of the relative spatial attitude of the sound pressure collection module arranged on the pan-tilt base; the keyboard realizes the input of relevant parameters in the electric scanning program control unit.

6. The device for detecting partial discharge of electrical equipment for capturing sound pressure of noise points according to claim 5, characterized in that: The electronic scanning program control unit realizes the reading of audio data under different time node parameter models by controlling the operating state of the pan-tilt base. The mixing processing unit includes an ultrasonic array data model and a correction instruction output terminal. The ultrasonic array data model includes a wave direction of arrival algorithm, an array structure, an array signal processing algorithm, and an audio splitting unit. The wave direction of arrival algorithm realizes the positioning of the direction of the audio. The array structure is the structure and spatial layout parameters of the equipment mounting frame and the sound pressure sensor in the sound pressure acquisition module. The array signal processing algorithm is a model parameter method based on AML. The audio splitting unit performs the processing of the parameters of the different time nodes. The relevant values ​​of inconsistent audio data attenuation under the time node parameter model are decomposed according to the relative energy attenuation ratio of frequency, hertz, timbre, periodic or regular amplitude. The ultrasonic array data model combines the different postures of the pan-tilt base in the different time node parameter models and the relative energy attenuation ratios of different frequencies, hertz, timbre, periodic or regular amplitudes in the audio to achieve the distinction, disassembly and positioning of the audio data; the correction instruction output end is connected to the electric scanning program control unit. When the data read by the ultrasonic array data model is incomplete, the correction instruction output end issues an instruction to the electric scanning program control unit to reset the motion trajectory.

7. The device for detecting partial discharge of electrical equipment for capturing sound pressure of noise points according to claim 6, characterized in that: The signal processing control unit identifies, filters out and outputs the disassembled, differentiated and located audio data according to the characteristics of the noise points.

8. The device for detecting partial discharge of electrical equipment by capturing sound pressure of noise points according to claim 7, characterized in that: The feedback output unit converts the audio data output by the signal processing control unit into a video signal or a distance parameter and sends the result to the display module.

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