CN105589020A - Detector and method for power distribution equipment inspection and live detection - Google Patents

Abstract

The invention provides a detector for power distribution equipment patrol inspection and live detection, which includes a sequentially connected composite sensor, a pre-processing unit, a thermal image acquisition unit, a map analysis unit, an analysis control and a communication unit; the composite sensor consists of Ultrasonic sensor, ground wave sensor and infrared thermal imaging sensor are formed to collect signals and convert them into analog electrical signals; the pre-processing unit performs filtering, amplification and denoising processing on the analog electrical signals; the thermal image acquisition unit synchronously acquires the processed analog electrical signals , and form a mixed digital code through the preset acquisition parameters and signal coding rules; the map analysis unit decodes the mixed digital code and forms a visualized partial positioning thermal image spectrum; the analysis control and communication unit displays the thermal image spectrum and outputs it to the outside equipment. By implementing the invention, the detection data of various detection methods can be integrated for comprehensive evaluation, the misjudgment rate of detection results can be reduced, the invention is convenient to carry, and the difficulty of electrification detection work is reduced.

Description

A detector and method for power distribution equipment inspection and live detection

technical field

The invention relates to the technical field of power distribution equipment inspection and detection, in particular to a detector and method for power distribution equipment inspection and live detection.

Background technique

In order to solve the growing demand for power supply and improve the reliability of power supply, the power sector has continuously introduced advanced technologies to strengthen the operation, maintenance and management of power distribution equipment. Ultrasonic, ground wave, infrared thermal imaging and other detection methods have become the inspection and testing methods for power distribution equipment. Necessary means for live detection. However, the detectors used for insulation testing of power distribution equipment are still in their infancy, although insulation testing technologies such as ultrasonic testing, geoelectric wave testing, and infrared thermal imaging testing have been widely used at home and abroad, and have achieved certain results. However, the degree of intelligence in detection is low, so that the judgment of insulation level and operating status of power distribution equipment is still based on manual experience.

In the actual on-site inspection, the above three methods are used to detect the insulation and state analysis of power distribution equipment, all of which have the following deficiencies: 1. Since the detection results of various detectors can only provide a single indicator and threshold alarm, making Comprehensive judgment relies on manual experience, resulting in the accuracy and reliability of the test results cannot be guaranteed; Second, due to the independent use of various detectors in the detection process, the detection data cannot be synchronized, and due to the differences in the background environment in different time periods , resulting in poor comparability among various test data (including ultrasonic partial discharge level, ground wave partial discharge level, infrared thermal temperature rise, etc.), making it difficult to make a comprehensive evaluation and easily causing misjudgment of test results; 3. The carrying capacity of the tester Too many and repeated operations are required, which increases the difficulty of live detection work.

Contents of the invention

The technical problem to be solved by the embodiments of the present invention is to provide a detector and method for power distribution equipment patrol inspection and live detection, which can comprehensively evaluate the detection data of various detection methods, reduce the misjudgment rate of detection results, And it is easy to carry, reducing the difficulty of live detection work.

In order to solve the above technical problems, an embodiment of the present invention provides a detector for power distribution equipment inspection and live detection, the detector includes a sequentially connected composite sensor, a pre-processing unit, a thermal image acquisition unit, Spectrum analysis unit and analysis control and communication unit; wherein,

The composite sensor is formed by an ultrasonic sensor, a ground wave sensor, and an infrared thermal image sensor, and is used to collect ultrasonic signals, ground wave signals, and infrared thermal image signals generated by power distribution equipment, and convert the collected ultrasonic signals, ground wave The signal and the infrared thermal image signal are respectively converted into corresponding analog electrical signals;

The pre-processing unit is used to filter, amplify and denoise the converted analog electrical signals respectively;

The thermal image acquisition unit is used to synchronously acquire the processed multiple analog electrical signals, and form a mixed digital code for the multiple synchronously acquired analog electrical signals through preset acquisition parameters and signal encoding rules ;

The spectrum analysis unit is used to decode the mixed digital code and form a visualized thermal image spectrum for local positioning;

The analysis control and communication unit is used to display the thermal image spectrogram and output the thermal image spectrogram to an external device.

Wherein, the ultrasonic sensor, the ground wave sensor and the infrared thermal image sensor in the composite sensor are integrated together through MEMS technology.

Wherein, the sampling amplitude range of the ultrasonic sensor is -20～65dBmV, and the center frequency is 40kHz; the sampling amplitude range of the ground wave sensor is 0～60dBmV, and the signal bandwidth is 3～60MHz; the infrared thermal imaging sensor The sampling amplitude range is 0°C~100°C, and the thermal image pixels are 320*240 pixels.

Wherein, the pre-processing unit includes a first filter amplifier circuit for filter amplification and denoising processing of ultrasonic signals and a second filter amplifier circuit for filter amplification and denoise processing of ground wave signals; wherein,

The first filter amplifier circuit is formed by a narrowband filter with a filter frequency of 40±2kHz and a signal amplifier with a power of 60dB, 80dB, or 100dB;

The second filtering and amplifying circuit is formed by a broadband filter with a filtering frequency of 3-60 MHz and two-stage signal amplifiers with powers of 20 dB and 40 dB respectively.

Wherein, the thermal image acquisition unit is formed by a field programmable gate array FPGA.

Wherein, the spectrum analysis unit is formed by a digital signal processing DSP chip.

Wherein, the analysis control and communication unit includes a liquid crystal display module, a wireless communication module and a wired communication module for displaying the thermal image spectrogram; wherein,

The wireless communication module includes one or more of GPRS sub-communication modules, Zigbee communication sub-modules, WIFI communication sub-modules and Bluetooth communication sub-modules;

The wired communication module includes one or more of a 10/100BASE-T adaptive Ethernet sub-module, an RS-485 interface sub-module, an RS-232 interface sub-module, and an optical fiber interface sub-module.

Wherein, the detector further includes a thermal image code memory, which is arranged between the thermal image acquisition unit and the spectrum analysis unit, and is used for storing the mixed digital code.

The embodiment of the present invention also provides a method for power distribution equipment inspection and live detection, which is implemented on the aforementioned detector, and the method includes:

Collect the ultrasonic signal, ground wave signal and infrared thermal image signal generated by the power distribution equipment, and convert the collected ultrasonic signal, ground wave signal and infrared thermal image signal into corresponding analog electrical signals;

performing filter amplification and denoising processing on the converted multiple analog electrical signals;

synchronously acquiring the processed multiple analog electrical signals, and forming a mixed digital code from the multiple synchronously acquired analog electrical signals through preset acquisition parameters and signal encoding rules;

decoding the hybrid digital code and forming a visualized partial localization thermogram; and

displaying the thermal image spectrogram, and outputting the thermal image spectrogram to an external device.

Wherein, the partial discharge localization thermal image spectrum includes defect location information, defect type information, partial discharge state information and insulation information of the power distribution equipment.

Implementing the embodiment of the present invention has the following beneficial effects:

1. In the embodiment of the present invention, since the composite sensor of the detector is integrated with an ultrasonic sensor, a ground wave sensor and an infrared thermal imaging sensor, the detector is convenient to carry and can be used for multiple purposes, avoiding the disadvantages of carrying too many detectors, And it can synchronize the detection data of multiple detection methods through the thermal image acquisition unit, and comprehensively evaluate the detection data, which reduces the misjudgment rate of detection results and reduces the difficulty of live detection work;

2. In the embodiment of the present invention, since the spectrum analysis unit of the detector can form a visualized thermal image spectrum, which can be displayed and output to external equipment for further analysis through the analysis control and communication unit, thereby improving the intelligent level of detection .

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. For those of ordinary skill in the art, obtaining other drawings based on these drawings still belongs to the scope of the present invention without any creative effort.

Figure 1 is a schematic diagram of the system structure of a detector for power distribution equipment inspection and live detection provided by an embodiment of the present invention;

Fig. 2 is a sampling flowchart of an application scenario of a thermal image sampling unit in a detector for power distribution equipment inspection and live detection provided by an embodiment of the present invention;

Fig. 3 is a flow chart of a method for power distribution equipment inspection and live detection provided by an embodiment of the present invention.

detailed description

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings.

As shown in Fig. 1, in the embodiment of the present invention, a detector for power distribution equipment inspection and live detection is provided. The detector includes a composite sensor 1 connected in sequence, a pre-processing unit 2, Thermal image acquisition unit 3, spectrum analysis unit 4 and analysis control and communication unit 5; wherein,

Composite sensor 1 is formed by an ultrasonic sensor, a ground wave sensor and an infrared thermal image sensor, and is used to collect ultrasonic signals, ground wave signals and infrared thermal image signals generated by power distribution equipment, and to collect the collected ultrasonic signals, ground wave signals and infrared thermal image signals. Thermal image signals are converted into corresponding analog electrical signals;

The pre-processing unit 2 is used to filter, amplify and denoise the converted analog electrical signals;

The thermal image acquisition unit 3 is used to synchronously acquire a plurality of analog electrical signals after processing, and form a mixed digital encoding of the synchronously acquired multiple analog electrical signals through preset acquisition parameters and signal encoding rules;

The spectrum analysis unit 4 is used to decode the mixed digital code, and form a visualized partial localization thermal image spectrogram;

The analysis control and communication unit 5 is used for displaying the thermal image spectrogram and outputting the thermal image spectrogram to an external device.

In the embodiment of the present invention, the composite sensor 1 is formed by an ultrasonic sensor, a ground wave sensor and an infrared thermal imaging sensor, and is integrated together through MEMS (Microelectromechanical Systems) technology, so that the composite sensor 1 can be integrated in a small space There are three sensors. It should be noted that the composite sensor 1 is processed with a special shielding device, which can suppress electromagnetic interference and prevent crosstalk between multiple signals.

In one embodiment, the composite sensor 1 includes three sensors: an ultrasonic sensor, a ground wave sensor and an infrared thermal image sensor; wherein, the sampling amplitude range of the ultrasonic sensor is -20 to 65dBmV, and the center frequency is 40kHz; The sampling amplitude range is 0~60dBmV, and the signal bandwidth is 3~60MHz; the sampling amplitude range of the infrared thermal imaging sensor is 0°C~100°C, and the thermal image pixels are 320*240 pixels.

In order to resist electromagnetic interference and suppress crosstalk, thereby outputting high-quality analog electrical signals, the pre-processing unit 2 includes a first filter amplifier circuit for filter amplification and denoising processing of ultrasonic signals and a first filter amplifier circuit for filter amplification and denoising of ground wave signals. Noise processing second filter amplifier circuit; Wherein,

The first filtering and amplifying circuit is formed by a narrow-band filter with a filtering frequency of 40±2kHz and a signal amplifier with a power of 60dB, 80dB, or 100dB;

The second filtering and amplifying circuit is formed by a broadband filter with a filtering frequency of 3-60MHz and two-stage signal amplifiers with powers of 20dB and 40dB respectively.

In the embodiment of the present invention, the thermal image acquisition unit 3 is formed by a field programmable gate array FPGA, which can be configured with a logic module CLB, an input and output module IOB and internal wiring to realize high-speed processing of multiple processed analog electrical signals. Synchronous acquisition, output mixed digital code through preset acquisition parameters and signal encoding rules.

In one embodiment, as shown in FIG. 2 , it is a sampling flowchart in the application scene of the thermal image acquisition unit 3. In order to collect different insulation signals synchronously, the thermal image acquisition unit 3 adopts high-speed time-division synchronous sampling technology to collect infrared images point by point. Thermal image signal, ultrasonic partial discharge signal, ground electric wave partial discharge signal.

The red thermal imaging pixel is 320x240=76800, the image frame frequency is 25Hz, and the sampling frequency is 76800x25=1.92MHz; the ultrasonic partial discharge signal sampling center frequency is 40kHz, according to the Nyquist law, the minimum undistorted sampling frequency is 80kHz; The discharge signal acquisition bandwidth is usually 3-60MHz. In order to reduce the volume of the present invention, envelope sampling technology is adopted, and the sampling frequency is 2MHz.

Therefore, the sampling frequency of the thermal image acquisition unit 3 formed by FPGA is designed to be 20MHz, which is used for high-fidelity synchronous sampling of infrared thermal image signals, ultrasonic partial discharge signals and ground wave partial discharge signals,

In the embodiment of the present invention, the map analysis unit 4 is formed by a digital signal processing DSP chip, by analyzing the defect location information (such as the specific location of the insulation defect), defect type information (such as the type of insulation defect), and the partial discharge state of the power distribution equipment. Information (such as the severity of partial discharge) and insulation information (such as insulation evaluation) and other information form a visualized partial discharge location thermal image spectrum.

In the embodiment of the present invention, the analysis control and communication unit 5 includes a liquid crystal display module, a wireless communication module and a wired communication module for displaying a thermal image spectrogram; wherein,

The wireless communication module includes one or more of GPRS sub-communication module, Zigbee communication sub-module, WIFI communication sub-module and Bluetooth communication sub-module;

The wired communication module includes one or more of a 10/100BASE-T adaptive Ethernet sub-module, an RS-485 interface sub-module, an RS-232 interface sub-module, and an optical fiber interface sub-module.

In the embodiment of the present invention, the detector also includes a thermal image encoding memory 6, which is arranged between the thermal image acquisition unit 3 and the atlas analysis unit 4, and is used to store mixed digital codes and store them frame by frame.

The working principle of power distribution equipment inspection and live detection in the embodiment of the present invention is as follows: the composite sensor 1 collects the ultrasonic signal, ground wave signal and temperature field distribution signal (obtained by the infrared thermal imaging sensor) generated by the power distribution equipment, And the collected ultrasonic signal, ground wave signal and temperature field distribution signal are converted into corresponding identifiable analog electrical signals, and filtered, amplified and denoised by the pre-processing unit 2 to form high-quality analog electrical signals The thermal image acquisition unit 3 performs cross-sampling and digital mixed encoding on the pre-processed mixed signal, and uses the thermal image encoding memory 6 to store it; the stored digital mixed encoding is processed and analyzed by the map analysis unit 4 to form a visualized Thermal image spectrogram for localized localization; display data through the analysis control and communication unit 5, control the collection process, and communicate and transmit the collected data and analysis results.

As shown in Figure 3, in the embodiment of the present invention, a method for power distribution equipment inspection and live detection is provided, which is implemented on the aforementioned detector, and the method includes:

Step S1, collecting the ultrasonic signal, ground wave signal and infrared thermal image signal generated by the power distribution equipment, and converting the collected ultrasonic signal, ground wave signal and infrared thermal image signal into corresponding analog electrical signals;

Step S2, performing filter amplification and denoising processing on the converted multiple analog electrical signals respectively;

Step S3, synchronously acquiring the processed multiple analog electrical signals, and forming a mixed digital code from the multiple synchronously acquired analog electrical signals through preset acquisition parameters and signal encoding rules;

Step S4, decoding the mixed digital code, and forming a visualized partial localization thermal image spectrogram;

Step S5, displaying the thermal image spectrogram, and outputting the thermal image spectrogram to an external device.

Wherein, the partial discharge localization thermal image spectrum includes defect location information, defect type information, partial discharge state information and insulation information of the power distribution equipment.

Implementing the embodiment of the present invention has the following beneficial effects:

1. In the embodiment of the present invention, since the composite sensor of the detector is integrated with an ultrasonic sensor, a ground wave sensor and an infrared thermal imaging sensor, the detector is convenient to carry and can be used for multiple purposes, avoiding the disadvantages of carrying too many detectors, And it can synchronize the detection data of multiple detection methods through the thermal image acquisition unit, and comprehensively evaluate the detection data, which reduces the misjudgment rate of detection results and reduces the difficulty of live detection work;

2. In the embodiment of the present invention, since the spectrum analysis unit of the detector can form a visualized thermal image spectrum, which can be displayed and output to external equipment for further analysis through the analysis control and communication unit, thereby improving the intelligent level of detection .

Those of ordinary skill in the art can understand that all or part of the steps in the method of the above-mentioned embodiments can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium, and the storage Media such as ROM/RAM, magnetic disk, optical disk, etc.

The above disclosures are only preferred embodiments of the present invention, and certainly cannot limit the scope of rights of the present invention. Therefore, equivalent changes made according to the claims of the present invention still fall within the scope of the present invention.

Claims (10)

1. A detector for power distribution equipment inspection and live detection is characterized by comprising a composite sensor (1), a preprocessing unit (2), a thermal image acquisition unit (3), an atlas analysis unit (4) and an analysis control and communication unit (5) which are sequentially connected; wherein,

the composite sensor (1) is formed by an ultrasonic sensor, a geoelectric wave sensor and an infrared thermal image sensor and is used for acquiring ultrasonic signals, geoelectric signals and infrared thermal image signals generated by power distribution equipment and respectively converting the acquired ultrasonic signals, geoelectric signals and infrared thermal image signals into corresponding analog electric signals;

the preprocessing unit (2) is used for respectively carrying out filtering amplification and denoising processing on the converted analog electric signals;

the thermal image acquisition unit (3) is used for synchronously acquiring the processed plurality of analog electric signals and forming a mixed digital code by the plurality of synchronously acquired analog electric signals according to preset acquisition parameters and signal coding rules;

the map analysis unit (4) is used for decoding the mixed digital code and forming a visual local discharge positioning thermal image map;

and the analysis control and communication unit (5) is used for displaying the thermal image spectrogram and outputting the thermal image spectrogram to external equipment.

2. The apparatus according to claim 1, wherein the ultrasonic sensor, the geoelectric sensor and the thermographic infrared sensor of the composite sensor (1) are integrated by MEMS technology.

3. The meter of claim 2, wherein the ultrasonic sensor has a sampling amplitude in the range of-20 to 65dBmV, a center frequency of 40 kHz; the sampling amplitude range of the ground electric wave sensor is 0-60 dBmV, and the signal bandwidth is 3-60 MHz; the sampling amplitude range of the infrared thermal image sensor is 0-100 ℃, and the thermal image pixels are 320x240 pixels.

4. The apparatus according to claim 1, wherein the pre-processing unit (2) comprises a first filter-amplifier circuit for filtering amplification and de-noising of the ultrasonic signals and a second filter-amplifier circuit for filtering amplification and de-noising of the ultrasonic signals; wherein,

the first filtering and amplifying circuit is formed by a narrow-band filter with filtering frequency of 40 +/-2 kHz and a signal amplifier with one of power of 60dB, 80dB and 100 dB;

the second filtering and amplifying circuit is formed by a broadband filter with the filtering frequency of 3-60MHz and two stages of signal amplifiers with the power of 20dB and 40dB respectively.

5. The detector according to claim 1, characterized in that the thermographic acquisition unit (3) is formed by a field programmable gate array FPGA.

6. The detector according to claim 1, characterized in that the profile analysis unit (4) is formed by a digital signal processing DSP chip.

7. The detector according to claim 1, characterized in that said analysis control and communication unit (5) comprises a liquid crystal display module, a wireless communication module and a wired communication module for displaying said thermographic spectrogram; wherein,

the wireless communication module comprises one or more of a GPRS sub-communication module, a Zigbee communication sub-module, a WIFI communication sub-module and a Bluetooth communication sub-module;

the wired communication module comprises one or more of 10/100BASE-T self-adaptive Ethernet sub-module, RS-485 interface sub-module, RS-232 interface sub-module and optical fiber interface sub-module.

8. The detector according to any one of claims 1 to 7, further comprising a thermographic code memory (6), the thermographic code memory (6) being arranged between the thermographic acquisition unit (3) and the atlas analysis unit (4) for storing the hybrid digital code.

9. A method for power distribution equipment inspection and live detection, implemented on a detector comprising any one of claims 1 to 8, the method comprising:

collecting ultrasonic signals, geoelectric wave signals and infrared thermal image signals generated by power distribution equipment, and respectively converting the collected ultrasonic signals, geoelectric wave signals and infrared thermal image signals into corresponding analog electric signals;

respectively carrying out filtering amplification and denoising treatment on the converted analog electric signals;

synchronously acquiring the processed plurality of analog electric signals, and forming a mixed digital code by the plurality of synchronously acquired analog electric signals according to preset acquisition parameters and signal coding rules;

decoding the mixed digital code and forming a visual partial discharge positioning thermal image spectrogram; and

and displaying the thermal image spectrogram and outputting the thermal image spectrogram to external equipment.

10. The method of claim 9, wherein the local discharge positioning thermal image spectrum comprises defect location information, defect type information, local discharge status information, and insulation information of the power distribution equipment.