Handheld power cable partial discharge monitoring system and method

Abstract

The invention discloses a handheld power cable partial discharge monitoring system and method, the system comprises a Fabry-Perot interference sensor, a signal processing unit, a data acquisition and storage module, a microprocessor and control unit and a display module which are electrically connected, and a fault recognition algorithm is embedded in the microprocessor and control unit; the Fabry-Perot interference sensor is composed of a pair of high-reflectivity mirrors which are arranged in parallel, and an interference cavity is formed between the two high-reflectivity mirrors; according to the power cable partial discharge detection device, the Fabry-Perot interference sensor is adopted to have extremely high sensitivity on weak discharge signals generated by power cable partial discharge, and the problem of the power cable partial discharge can be detected in the early stage; parameters of partial discharge signals can be accurately analyzed, and reliable data support is provided for fault diagnosis.

Description

Technical Field

[0001] The present invention relates to the technical field of power cable inspection, and in particular to a handheld power cable partial discharge monitoring system and method. Background Art

[0002] During the operation of power cables, partial discharge may cause insulation aging and damage, which in turn leads to power failures. Traditional partial discharge monitoring methods have some limitations. For example, some equipment is bulky and inconvenient to carry, which is not suitable for rapid on-site detection and diagnosis; some monitoring technologies are not sensitive enough to accurately detect weak partial discharge signals; and other methods are complicated to operate and require professional technicians to spend a lot of time for detection and analysis. Therefore, a convenient, efficient and accurate handheld partial discharge monitoring system is needed to meet the needs of on-site power cable detection. Summary of the invention

[0003] In view of the deficiencies in the prior art, the present invention provides a handheld power cable partial discharge monitoring system and method to solve the problems raised in the above background technology.

[0004] To achieve the above object, the present invention provides the following technical solution: a handheld power cable partial discharge monitoring system, comprising:

[0005] Fabry-Perot interferometer sensor, used to collect mechanical wave vibration signals generated when partial discharge occurs in power cables and convert them into optical signals;

[0006] A signal processing unit, the signal processing unit is electrically connected to the Fabry-Perot interferometer sensor, and is used to receive the optical signal transmitted by the Fabry-Perot interferometer sensor and convert the optical information into an electrical signal;

[0007] A data acquisition and storage module, which is electrically connected to the signal processing unit and is used to receive the electrical signal transmitted by the signal processing unit and convert the electrical signal into a digital signal for storage;

[0008] The microprocessor and the control unit are electrically connected to the data acquisition and storage module, and are used to receive the digital signal transmitted by the data acquisition and storage module, and process the digital signal to obtain the diagnosis result;

[0009] The display module is electrically connected to the microprocessor and the control unit, and is used to receive and display the diagnosis results transmitted by the microprocessor and the control unit.

[0010] Furthermore, the Fabry-Perot interferometer sensor is composed of a pair of high reflectivity mirrors arranged in parallel, and an interference cavity is formed between the two high reflectivity mirrors.

[0011] Furthermore, it also includes a power module, which is electrically connected to the Fabry-Perot interferometer sensor, the signal processing unit, the data acquisition and storage module, the microprocessor and the control unit, and the display module, and is used to provide a stable power supply to the Fabry-Perot interferometer sensor, the signal processing unit, the data acquisition and storage module, the microprocessor and the control unit, and the display module.

[0012] Furthermore, the handheld housing is used to encapsulate the Fabry-Perot interferometer sensor, the signal processing unit, the data acquisition and storage module, the microprocessor and control unit, the display module and the power module.

[0013] Further, the signal processing unit includes a photodetector, a preamplifier and a filter.

[0014] A handheld power cable partial discharge monitoring method is applied to a handheld power cable partial discharge monitoring system, comprising:

[0015] Step S1: collecting mechanical wave vibration signals generated when partial discharge occurs in the power cable through a Fabry-Perot interferometer sensor to obtain optical signals;

[0016] Step S2: converting the collected optical signal into an electrical signal through an electrical conversion module and a filtering module;

[0017] Step S3: converting the electrical signal into a digital signal through the data acquisition module, and storing the digital signal through the storage module;

[0018] Step S4: embedding the fault identification algorithm into the microprocessor and the control unit, and processing the digital signal through the microprocessor and the control unit to obtain a diagnosis result;

[0019] Step S5: Display the obtained diagnosis result through the display module.

[0020] Further, in step S1, an optical signal is obtained, and the specific process is as follows:

[0021] When partial discharge occurs in the power cable, a mechanical wave vibration signal is generated. The mechanical wave vibration signal is sensed by the Fabry-Perot interferometer sensor. The mechanical wave vibration signal is preprocessed by using the wavelet threshold denoising method. The mechanical wave vibration signal is decomposed into wavelet components of different sizes, and the threshold of the noise is determined according to the characteristics of the wavelet components. Finally, the wavelet component of the threshold is removed to achieve the purpose of denoising and obtain the optical signal.

[0022] Further, in step S4, the diagnosis result is obtained, and the specific process is as follows:

[0023] The voiceprint data of the digital signal is preprocessed through the convolutional neural network of the fault recognition algorithm to generate a data set, and the data set is divided into a training set and a test set. The convolutional neural network is trained with the training set to obtain the trained model, and the trained model is verified with the test set to obtain the diagnosis result.

[0024] Compared with the existing technology, the present invention has the following beneficial effects:

[0025] (1) The present invention uses a Fabry-Perot interferometer sensor with extremely high sensitivity to weak discharge signals generated by partial discharge of power cables, which can detect partial discharge problems of power cables at an early stage, thus facilitating timely measures to avoid further development of faults.

[0026] (2) The present invention adopts a handheld housing design so that the system can be conveniently carried to the power cable site for detection without complicated installation and debugging process. The operator can quickly scan and detect the power cable, which greatly improves the detection efficiency.

[0027] (3) The present invention can accurately analyze the parameters of partial discharge signals, such as amplitude, frequency, phase, etc., by setting a fault identification algorithm, and provide reliable data support for fault diagnosis. At the same time, intelligent alarms can be issued based on historical data and preset thresholds to prompt operators to pay attention to potential problems.

[0028] (4) The present invention ensures that the system can work stably for a long time on site through rechargeable batteries and energy-saving circuits, reduces the interruption of detection due to insufficient power, and improves the continuity of detection work. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a flow chart of the present invention.

[0030] Figure 2 This is a structural diagram of the interference cavity of the Fabry-Perot interferometer sensor of the present invention.

[0031] Figure 3 This is a convolutional neural network fault diagnosis flow chart of the present invention. DETAILED DESCRIPTION

[0032] like Figure 1 As shown, the present invention provides a technical solution: a handheld power cable partial discharge monitoring system, comprising:

[0033] Fabry-Perot interferometer sensor, used to collect mechanical wave vibration signals generated when partial discharge occurs in power cables and convert them into optical signals;

[0034] A signal processing unit, the signal processing unit is electrically connected to the Fabry-Perot interferometer sensor, and is used to receive the optical signal transmitted by the Fabry-Perot interferometer sensor and convert the optical information into an electrical signal;

[0035] A data acquisition and storage module, which is electrically connected to the signal processing unit and is used to receive the electrical signal transmitted by the signal processing unit and convert the electrical signal into a digital signal for storage;

[0036] The microprocessor and the control unit are electrically connected to the data acquisition and storage module, and are used to receive the digital signal transmitted by the data acquisition and storage module, and process the digital signal to obtain the diagnosis result;

[0037] The display module is electrically connected to the microprocessor and the control unit, and is used to receive and display the diagnosis results transmitted by the microprocessor and the control unit.

[0038] It also includes a power module, which is electrically connected to the Fabry-Perot interferometer sensor, signal processing unit, data acquisition and storage module, microprocessor and control unit and display module, and is used to provide a stable power supply to the Fabry-Perot interferometer sensor, signal processing unit, data acquisition and storage module, microprocessor and control unit and display module, and the power supply is 12V DC; the power module uses a rechargeable battery and has a battery management system, which can monitor the battery power in real time and issue a prompt when the battery is low; at the same time, the power module is designed with an energy-saving circuit to reduce energy consumption and extend the battery life.

[0039] Among them, it also includes a handheld housing with an ergonomic housing design for easy handheld operation; the housing material has good mechanical strength and anti-electromagnetic interference performance, and can protect internal components from the influence of the external environment; the handheld housing is provided with a sensor interface, a charging interface, a display window and a reasonable layout of operation buttons for user convenience; the handheld housing is used to encapsulate the Fabry-Perot interferometer sensor, the signal processing unit, the data acquisition and storage module, the microprocessor and control unit, the display module and the power module.

[0040] like Figure 2 As shown, the Brillouin-Perot interferometer sensor:

[0041] It is designed based on the principle of Fabry-Perot interferometer sensor; the Fabry-Perot interferometer sensor consists of a pair of high-reflectivity mirrors arranged in parallel, and an interference cavity is formed between the two high-reflectivity mirrors; when a local discharge signal occurs in the power cable, the generated vibration signals such as ultrasonic waves and electromagnetic pulses will cause the optical length of the interference cavity to change, thereby causing the movement of the interference fringes; by detecting the movement and change of the interference fringes, the optical signal related to the local discharge can be obtained; the Fabry-Perot interferometer sensor has high sensitivity and good frequency response characteristics, and can accurately capture weak local discharge signals.

[0042] Among them, the signal processing unit processing process:

[0043] The signal processing unit is connected to the Fabry-Perot interferometer sensor module and is used to receive the optical signal change information output by the Fabry-Perot interferometer sensor; the signal processing unit includes a photodetector, a preamplifier, a filter and other circuits. The photodetector converts the optical signal into an electrical signal, and the preamplifier, the filter and other circuits amplify and filter the optical signal to remove noise interference, enhance the optical signal, and improve the quality and recognizability of the signal.

[0044] Among them, the data acquisition and storage module processing process:

[0045] The data acquisition and storage module is connected to the signal processing unit and is responsible for collecting the processed electrical signals and converting them into digital signals. The data acquisition and storage module has a high-speed sampling function and can accurately record the waveform and parameters of the partial discharge electrical signal. The collected digital signals are stored in the internal memory and can support large-capacity storage for subsequent analysis and processing of the digital signals.

[0046] Among them, the microprocessor and control unit process:

[0047] The microprocessor controls and coordinates the entire monitoring process. It is used to receive the digital signal output by the data acquisition and storage module. The microprocessor and the control unit run the fault identification algorithm to analyze the digital signal, identify and determine whether there is a partial discharge signal in the power cable, and evaluate the intensity, location and other parameters of the discharge to obtain the diagnosis result. At the same time, the microprocessor and the control unit also interact with the display module.

[0048] Among them, the display module processing process:

[0049] The display module provides users with an intuitive operation interface and monitoring result display; it uses a liquid crystal display (LCD) or other suitable display technology to display the waveform, parameters (such as discharge amplitude, frequency, etc.), alarm information, etc. of the partial discharge signal in the diagnosis results; there are multiple operation buttons on the operation interface, and users can start or stop monitoring and set monitoring parameters (such as sampling frequency, threshold, etc.) through buttons.

[0050] Handheld housing assembly process:

[0051] During the manufacturing process, the Fabry-Perot interferometer sensor module, signal processing unit, data acquisition and storage module, microprocessor and control unit, display module, power module and other components are installed in the casing according to the design requirements, and the circuits are connected and debugged; after the assembly is completed, initialization settings are performed to set the default sampling frequency, threshold and other parameters.

[0052] A handheld power cable partial discharge monitoring method is applied to a handheld power cable partial discharge monitoring system, comprising:

[0053] Step S1: collecting mechanical wave vibration signals generated when partial discharge occurs in the power cable through a Fabry-Perot interferometer sensor to obtain optical signals;

[0054] Step S2: converting the collected optical signal into an electrical signal through an electrical conversion module and a filtering module;

[0055] Step S3: converting the electrical signal into a digital signal through the data acquisition module, and storing the digital signal through the storage module;

[0056] Step S4: embedding the fault identification algorithm into the microprocessor and the control unit, and processing the digital signal through the microprocessor and the control unit to obtain a diagnosis result;

[0057] Step S5: Display the obtained diagnosis result through the display module.

[0058] Wherein, in step S1, an optical signal is obtained, and the specific process is as follows:

[0059] When partial discharge occurs in the power cable, a mechanical wave vibration signal is generated. The mechanical wave vibration signal is sensed by the Fabry-Perot interferometer sensor. The mechanical wave vibration signal is preprocessed by using the wavelet threshold denoising method. The mechanical wave vibration signal is decomposed into wavelet components of different sizes, and the threshold of the noise is determined according to the characteristics of the wavelet components. Finally, the wavelet component of the threshold is removed to achieve the purpose of denoising and obtain the optical signal.

[0060] like Figure 3 As shown, in step S4, the diagnosis result is obtained, and the specific process is as follows:

[0061] The voiceprint data of the digital signal is preprocessed through the convolutional neural network of the fault recognition algorithm to generate a data set, and the data set is divided into a training set and a test set. The convolutional neural network is trained with the training set to obtain the trained model, and the trained model is verified with the test set to obtain the diagnosis result.

[0062] Microprocessor and control unit data processing and analysis:

[0063] After the test is completed, the data from the handheld housing can be transmitted to an external computer or other analysis device through the data interface; on the external device, special data analysis software can be used to conduct a more in-depth analysis of the collected data, such as drawing a discharge trend graph, comparing data from different test points, etc., in order to better evaluate the overall health of the power cable and formulate a maintenance plan.

[0064] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A handheld power cable partial discharge monitoring system, characterized in that: include: Fabry-Perot interferometer sensor, used to collect mechanical wave vibration signals generated when partial discharge occurs in power cables and convert them into optical signals; A signal processing unit, the signal processing unit is electrically connected to the Fabry-Perot interferometer sensor, and is used to receive the optical signal transmitted by the Fabry-Perot interferometer sensor and convert the optical information into an electrical signal; A data acquisition and storage module, which is electrically connected to the signal processing unit and is used to receive the electrical signal transmitted by the signal processing unit and convert the electrical signal into a digital signal for storage; The microprocessor and the control unit are electrically connected to the data acquisition and storage module, and are used to receive the digital signal transmitted by the data acquisition and storage module, and process the digital signal to obtain the diagnosis result; The display module is electrically connected to the microprocessor and the control unit, and is used to receive and display the diagnosis results transmitted by the microprocessor and the control unit.

2. A handheld power cable partial discharge monitoring system according to claim 1, characterized in that: The Fabry-Perot interferometer sensor consists of a pair of high-reflectivity mirrors arranged in parallel, and an interference cavity is formed between the two high-reflectivity mirrors.

3. A handheld power cable partial discharge monitoring system according to claim 2, characterized in that: It also includes a power module, which is electrically connected to the Fabry-Perot interferometer sensor, the signal processing unit, the data acquisition and storage module, the microprocessor and the control unit, and the display module, and is used to provide a stable power supply to the Fabry-Perot interferometer sensor, the signal processing unit, the data acquisition and storage module, the microprocessor and the control unit, and the display module.

4. A handheld power cable partial discharge monitoring system according to claim 3, characterized in that: The handheld housing is used to encapsulate the Fabry-Perot interferometer sensor, the signal processing unit, the data acquisition and storage module, the microprocessor and control unit, the display module and the power module.

5. A handheld power cable partial discharge monitoring system according to claim 4, characterized in that: The signal processing unit includes a photodetector, a preamplifier and a filter.

6. A handheld power cable partial discharge monitoring method, applied to a handheld power cable partial discharge monitoring system according to claims 1-5, characterized in that: include: Step S1: collecting mechanical wave vibration signals generated when partial discharge occurs in the power cable through a Fabry-Perot interferometer sensor to obtain optical signals; Step S2: converting the collected optical signal into an electrical signal through an electrical conversion module and a filtering module; Step S3: converting the electrical signal into a digital signal through the data acquisition module, and storing the digital signal through the storage module; Step S4: embedding the fault identification algorithm into the microprocessor and the control unit, and processing the digital signal through the microprocessor and the control unit to obtain a diagnosis result; Step S5: Display the obtained diagnosis result through the display module.

7. A handheld power cable partial discharge monitoring method according to claim 6, characterized in that: In step S1, an optical signal is obtained, and the specific process is as follows: When partial discharge occurs in the power cable, a mechanical wave vibration signal is generated. The mechanical wave vibration signal is sensed by the Fabry-Perot interferometer sensor. The mechanical wave vibration signal is preprocessed by using the wavelet threshold denoising method. The mechanical wave vibration signal is decomposed into wavelet components of different sizes, and the threshold of the noise is determined according to the characteristics of the wavelet components. Finally, the wavelet component of the threshold is removed to achieve the purpose of denoising and obtain the optical signal.

8. A handheld power cable partial discharge monitoring method according to claim 7, characterized in that: The diagnostic result is obtained in step S4, and the specific process is as follows: The voiceprint data of the digital signal is preprocessed through the convolutional neural network of the fault recognition algorithm to generate a data set, and the data set is divided into a training set and a test set. The convolutional neural network is trained with the training set to obtain the trained model, and the trained model is verified with the test set to obtain the diagnosis result.

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