阅读说明：本技术 基于气体特征的高压电缆隐蔽缺陷检测方法及系统 (High-voltage cable hidden defect detection method and system based on gas characteristics ) 是由 段肖力 刘三伟 段建家 黄福勇 曾泽宇 于 2021-11-12 设计创作，主要内容包括：本发明公开了一种基于气体特征的高压电缆隐蔽缺陷检测方法及系统,本发明方法包括检测高压电缆的封闭内腔中的气体成分；将气体成分与预设的隐蔽缺陷映射表确定高压电缆隐蔽缺陷状态,所述隐蔽缺陷映射表包含了主要气体成分、高压电缆隐蔽缺陷状态之间的映射关系。现有研究表明由半导电层和金属护层之间形成的不均匀空气间隙中存在微量气体,这些微量气体由金属护套内绝缘结构的缺陷而释放形成,本发明基于高压电缆的封闭内腔中的气体成分来确定高压电缆隐蔽缺陷状态,能够发现人工巡检不能发现的高压电缆隐蔽缺陷状态,而且相对DR检测方法而言所用设备较小、成本较低,尤其适用于对高压电缆的长期在线监测。(The invention discloses a high-voltage cable hidden defect detection method and a system based on gas characteristics, wherein the method comprises the steps of detecting gas components in a closed inner cavity of a high-voltage cable; and determining the hidden defect state of the high-voltage cable by using the gas component and a preset hidden defect mapping table, wherein the hidden defect mapping table comprises the mapping relation between the main gas component and the hidden defect state of the high-voltage cable. The invention determines the hidden defect state of the high-voltage cable based on the gas components in the closed inner cavity of the high-voltage cable, can find the hidden defect state of the high-voltage cable which cannot be found by manual inspection, has smaller equipment and lower cost compared with a DR detection method, and is particularly suitable for long-term online monitoring of the high-voltage cable.)

1. A high-voltage cable hidden defect detection method based on gas characteristics is characterized by comprising the following steps:

1) detecting gas components in a closed inner cavity of the high-voltage cable;

2) and determining the hidden defect state of the high-voltage cable by using the gas component and a preset hidden defect mapping table, wherein the hidden defect mapping table comprises the mapping relation between the main gas component and the hidden defect state of the high-voltage cable.

2. The high voltage cable covert defect detection method based on gas characteristics of claim 1, wherein the high voltage cable covert defect state refers to a defect state of an insulation structure in a metal sheath, the insulation structure in the metal sheath comprises a buffer layer, an insulating outer semi-conductive shielding layer and a main insulation layer, the defect state comprises a normal state, and a single layer of the buffer layer, the insulating outer semi-conductive shielding layer and the main insulation layer has defects and a combination of more than two layers has defects.

3. The high voltage cable covert defect detection method based on gas characteristics as claimed in claim 2, wherein said covert defect map comprises a mapping relationship between gas components and covert defect states of the high voltage cable, and a main gas component corresponding to defects existing in a single buffer layer is H₂And CO₂The main gas component corresponding to the defect of the single insulating outer semi-conductive shielding layer is CO₂The main gas components corresponding to the defects of the single main insulating layer are the ethylene oxide acetaldehyde and acetone; the combination of two or more layers having defects corresponds to a combination of gas components corresponding to defects in a single layer.

4. The method for detecting the hidden defects of the high-voltage cable based on the gas characteristics as claimed in claim 2, wherein the step 1) of detecting the gas components in the closed cavity of the high-voltage cable is performed in a timed trigger manner, and the step of recording the detected gas components is further included after each detection of the gas components in the closed cavity of the high-voltage cable.

5. The method of claim 4, wherein in step 2) the gas composition and the predetermined hidden defect map are used to determine the hidden defect status of the high voltage cable, if the defect status is a single defect or a combination of two or more layers of the buffer layer, the outer insulating semi-conductive shielding layer and the main insulating layer, the method further comprises determining the gas generation rate and the change of the gas composition based on the recorded history of the gas composition, and the hidden defect status of the high voltage cable at a plurality of previous moments to obtain the development status of the hidden defect status of the high voltage cable.

6. A gas signature based high voltage cable covert defect detection system comprising a microprocessor and a memory interconnected, wherein the microprocessor is programmed or configured to perform the steps of the gas signature based high voltage cable covert defect detection method of any one of claims 1-5.

7. A computer readable storage medium having stored thereon a computer program programmed or configured to perform the gas signature based high voltage cable covert defect detection method of any of claims 1-5.

8. A high-voltage cable hidden defect detection system based on gas characteristics is characterized by comprising a gas component acquisition unit (1), a defect detection unit (2) and a high-voltage cable (3) as a repaired object, the end part of the high-voltage cable (3) is closed, the high-voltage cable (3) is provided with more than two air nozzles (31) which are communicated with a cavity (30) between the internal buffer layer and the metal sheath, and one of the air nozzles (31) is connected with the input end of the gas component acquisition unit (1), the gas component acquisition unit (1) is communicated with the closed inner cavity of the detected high-voltage cable to detect the gas components in the closed inner cavity, the output end of the gas component acquisition unit (1) is connected with the defect detection unit (2), the defect detection unit (2) is programmed or configured to perform the steps of the gas signature based high voltage cable covert defect detection method of any one of claims 1-5.

9. The gas signature-based high voltage cable covert defect detection system of claim 8, wherein said gas composition collection unit comprises H₂Sensor, CO₂Sensor and ringAn ethylene oxide sensor, said H₂Sensor, CO₂The output ends of the sensor and the ethylene oxide sensor are respectively connected with the defect detection unit (2).

10. The high voltage cable covert defect detection system based on gas signature of claim 9, wherein said defect detection unit (2) comprises a signal processing module (21), a microprocessor (22), a wireless communication module (23) and an energy supply module (24), said H₂Sensor, CO₂The output ends of the sensor and the ethylene oxide sensor are respectively connected with a microprocessor (22) through a signal processing module (21), the microprocessor (22) is connected with a wireless communication module (23), and the output end of an energy supply module (24) is respectively connected with H₂Sensor, CO₂The sensor, the ethylene oxide sensor, the signal processing module (21), the microprocessor (22) and the power supply terminal of the wireless communication module (23) are connected.

Technical Field

The invention relates to a high-voltage cable defect detection technology, in particular to a high-voltage cable hidden defect detection method and system based on gas characteristics.

Background

The high-voltage cable is the core power equipment for city power supply. The traditional high-voltage cable is a complete closed structure and consists of a conductor, a main insulator, an insulating shielding layer, a semi-conducting layer, a metal protective layer and an outer sheath from inside to outside, and is a relatively closed whole in structure. The defects of the outer sheath can be found through manual inspection. However, for the hidden defect of the high-voltage cable, manual inspection is impossible. In order to realize the hidden defect detection of the high-voltage cable, a DR detection method is adopted at present, namely, X-rays are adopted to image the hidden defect detection of the high-voltage cable so as to realize the hidden defect detection of the high-voltage cable. However, the DR detection method is generally only used for offline detection of cables in fixed places due to the large size, high price and high cost of equipment, and even if the DR detection method is modified to be suitable for online detection, the DR detection method still has the limitations of large size and high cost of equipment, and cannot be used for realizing long-term detection of high-voltage cables.

Disclosure of Invention

The technical problems to be solved by the invention are as follows: aiming at the problems in the prior art, a high-voltage cable hidden defect detection method and system based on gas characteristics are provided. The invention determines the hidden defect state of the high-voltage cable based on the gas components in the closed inner cavity of the high-voltage cable, can find the hidden defect state of the high-voltage cable which cannot be found by manual inspection, has smaller equipment and lower cost compared with a DR detection method, and is particularly suitable for long-term online monitoring of the high-voltage cable.

In order to solve the technical problems, the invention adopts the technical scheme that:

a high-voltage cable hidden defect detection method based on gas characteristics comprises the following steps:

1) detecting gas components in a closed inner cavity of the high-voltage cable;

2) and determining the hidden defect state of the high-voltage cable by using the gas component and a preset hidden defect mapping table, wherein the hidden defect mapping table comprises the mapping relation between the main gas component and the hidden defect state of the high-voltage cable.

Optionally, the high-voltage cable hidden defect state refers to a defect state of an insulation structure in a metal sheath, the insulation structure in the metal sheath is composed of a buffer layer, an insulation outer semi-conductive shielding layer and a main insulation layer, the defect state includes a normal state, and a single layer of the buffer layer, the insulation outer semi-conductive shielding layer and the main insulation layer has defects and a combination of more than two layers has defects.

Optionally, the hidden defect map includes a mapping relationship between gas components and hidden defect states of the high-voltage cable, and the main gas component corresponding to the defect existing in the single buffer layer is H₂And CO₂The main gas component corresponding to the defect of the single insulating outer semi-conductive shielding layer is CO₂The main gas components corresponding to the defects of the single main insulating layer are the ethylene oxide acetaldehyde and acetone; the combination of two or more layers having defects corresponds to a combination of gas components corresponding to defects in a single layer.

Optionally, the step 1) of detecting the gas component in the closed inner cavity of the high-voltage cable is performed by timing triggering, and a step of recording the detected gas component is further included after each detection of the gas component in the closed inner cavity of the high-voltage cable.

Optionally, when the hidden defect state of the high-voltage cable is determined by the gas composition and the preset hidden defect mapping table in step 2), if the defect state is that a single layer of the buffer layer, the insulating outer semiconductive shielding layer and the main insulating layer has a defect or a combination of more than two layers has a defect, determining the gas production speed and the change of the gas composition based on the recorded history of the gas composition, and determining the hidden defect state of the high-voltage cable at a plurality of previous moments so as to obtain the development condition of the hidden defect state of the high-voltage cable.

In addition, the invention also provides a high-voltage cable covert defect detection system based on gas characteristics, which comprises a microprocessor and a memory which are connected with each other, wherein the microprocessor is programmed or configured to execute the steps of the high-voltage cable covert defect detection method based on gas characteristics.

Furthermore, the present invention also provides a computer readable storage medium having stored therein a computer program programmed or configured to execute the gas signature-based high voltage cable covert defect detection method.

In addition, the invention also provides a high-voltage cable concealed defect detection system based on gas characteristics, which comprises a gas component acquisition unit, a defect detection unit and a high-voltage cable serving as a repaired object, wherein the end part of the high-voltage cable is closed, the high-voltage cable is provided with more than two gas nozzles communicated with a cavity between an internal buffer layer and a metal sheath, one of the gas nozzles is connected with the input end of the gas component acquisition unit, the gas component acquisition unit is communicated with the closed inner cavity of the high-voltage cable to be detected so as to detect the gas components in the closed inner cavity, the output end of the gas component acquisition unit is connected with the defect detection unit, and the defect detection unit is programmed or configured to execute the steps of the high-voltage cable concealed defect detection method based on the gas characteristics.

Optionally, the gas component collection unit comprises H₂Sensor, CO₂Sensor and ethylene oxide sensor, said H₂Sensor, CO₂The output ends of the sensor and the ethylene oxide sensor are respectively connected with a defect detection unitAre connected.

Optionally, the defect detecting unit comprises a signal processing module, a microprocessor, a wireless communication module and an energy supply module, and the H₂Sensor, CO₂The output ends of the sensor and the ethylene oxide sensor are respectively connected with the microprocessor through the signal processing module, the microprocessor is connected with the wireless communication module, and the output end of the energy supply module is respectively connected with the H₂Sensor, CO₂The sensor, the ethylene oxide sensor, the signal processing module, the microprocessor and the power supply terminal of the wireless communication module are connected.

Compared with the prior art, the invention has the following advantages:

1. the prior studies show that trace gases exist in the uneven air gap formed between the semi-conducting layer and the metal sheath, and the trace gases are released and formed by the defects of the insulating structure in the metal sheath; the hidden defect state of the high-voltage cable is determined by the gas composition and a preset hidden defect mapping table, the hidden defect mapping table contains the mapping relation between the main gas composition and the hidden defect state of the high-voltage cable, the hidden defect state of the high-voltage cable is determined based on the gas composition in a closed inner cavity of the high-voltage cable, and the hidden defect state of the high-voltage cable which cannot be found by manual inspection can be found.

2. The method determines the hidden defect state of the high-voltage cable based on the gas components in the closed inner cavity of the high-voltage cable, has smaller equipment and lower cost compared with a DR detection method, and is particularly suitable for long-term online monitoring of the high-voltage cable.

Drawings

FIG. 1 is a schematic diagram of a basic flow of a method according to an embodiment of the present invention.

Fig. 2 is a schematic structural diagram of a system according to an embodiment of the present invention.

Fig. 3 is a schematic diagram of an electrical principle framework of the system according to the embodiment of the present invention.

Detailed Description

As shown in fig. 1, the method for detecting concealed defects of a high-voltage cable based on gas characteristics in the embodiment includes:

1) detecting gas components in a closed inner cavity of the high-voltage cable;

2) and determining the hidden defect state of the high-voltage cable by using the gas component and a preset hidden defect mapping table, wherein the hidden defect mapping table comprises the mapping relation between the main gas component and the hidden defect state of the high-voltage cable.

In this embodiment, the hidden defect state of the high-voltage cable refers to a defect state of an insulation structure in a metal sheath, the insulation structure in the metal sheath includes a buffer layer, an insulation outer semiconductive shielding layer and a main insulation layer, and the defect state includes a normal state, and a single layer of the buffer layer, the insulation outer semiconductive shielding layer and the main insulation layer has a defect and a combination of more than two layers has a defect, for example, the buffer layer + the insulation outer semiconductive shielding layer, the buffer layer + the main insulation layer, the insulation outer semiconductive shielding layer + the main insulation layer, and the like. It should be noted that the buffer layer, the insulating outer semiconductive shielding layer and the main insulating layer are all an internal insulating structure form of the existing high-voltage cable, and the method of this embodiment does not depend on a specific internal insulating structure form.

In this embodiment, the hidden defect mapping table includes mapping relationships between gas components and hidden defect states of the high-voltage cable, and the main gas component corresponding to the defect existing in the single buffer layer is H₂And CO₂The main gas component corresponding to the defect of the single insulating outer semi-conductive shielding layer is CO₂Ethylene oxide Acetaldehyde and Acetone, and main gas components corresponding to defects of the single main insulating layer are ethylene oxide Acetaldehyde (Acetaldehyde) and Acetone (Acetone); the combination of two or more layers having defects corresponds to a combination of gas components corresponding to defects in a single layer. Can adopt H according to the needs₂Sensor, CO₂Sensors and ethylene oxide sensors to achieve the detection of the gas components.

It should be noted that the method of the present embodiment can be used for single detection, and is particularly suitable for long-term online monitoring of high-voltage cables. In order to implement long-term online monitoring of the high-voltage cable, in this embodiment, step 1) of detecting the gas component in the closed inner cavity of the high-voltage cable is executed by timing trigger, and after detecting the gas component in the closed inner cavity of the high-voltage cable each time, the method further includes a step of recording the detected gas component.

In the process of long-term online monitoring of the high-voltage cable, in order to more clearly understand the development of hidden defects of the high-voltage cable, in step 2) of the present embodiment, when the state of hidden defects of the high-voltage cable is determined by using the gas components and the preset hidden defect mapping table, if the state of defects is that a single layer of the buffer layer, the outer insulating semiconductive shielding layer and the main insulating layer has defects or that a combination of more than two layers has defects, the method further includes determining the gas generation speed and the change of the gas components based on the recorded history records of the gas components, and the current previous hidden defect states of the high-voltage cable at multiple moments, so as to obtain the development condition of the hidden defect state of the high-voltage cable. After the development condition of the hidden defect state of the high-voltage cable is obtained, all information of the hidden defect state of the high-voltage cable, gas production speed, gas composition and the like can be generated into a chart report for fault detection and analysis and high-voltage cable performance analysis.

In addition, the present embodiment also provides a high voltage cable covert defect detection system based on gas characteristics, which comprises a microprocessor and a memory connected with each other, wherein the microprocessor is programmed or configured to execute the steps of the high voltage cable covert defect detection method based on gas characteristics.

Furthermore, the present embodiment also provides a computer readable storage medium having stored therein a computer program programmed or configured to execute the foregoing gas signature-based high voltage cable covert defect detection method.

In addition, as shown in fig. 2 and fig. 3, the embodiment further provides a high voltage cable hidden defect detecting system based on gas characteristics, which includes a gas component collecting unit 1, a defect detecting unit 2 and a high voltage cable 3 as a repaired object, wherein an end of the high voltage cable 3 is closed, the high voltage cable 3 has a cavity (30) communicated with an internal buffer layer and a metal sheath, and more than two gas nozzles 31 are arranged, one of the gas nozzles 31 is connected with an input end of the gas component collecting unit 1, the gas component collecting unit 1 is communicated with the closed inner cavity of the detected high voltage cable to detect gas components in the closed inner cavity, an output end of the gas component collecting unit 1 is connected with the defect detecting unit 2, and the defect detecting unit 2 is programmed or configured to execute the steps of the high voltage cable hidden defect detecting method based on gas characteristics. The defect detection unit 2 can determine the hidden defect state of the high-voltage cable by detecting the gas components in the closed inner cavity of the high-voltage cable and combining the gas components with a preset hidden defect mapping table.

In order to facilitate the sealing of the cavity 30 between the buffer layer and the metal sheath of the high voltage cable 3 after the repair of the buffer layer of the high voltage cable is completed and to prevent external moisture from entering the cavity 30 between the buffer layer and the metal sheath of the high voltage cable 3, as shown in fig. 2, in this embodiment, the air tap 31 is provided with a valve 32. The valve 32 can conveniently control the opening state of the air tap 31, and the air tap is opened when the high-voltage cable concealed defect detection operation is carried out, and is closed after the high-voltage cable concealed defect detection operation is completed, so that external moisture is prevented from entering the cavity 30 between the buffer layer and the metal sheath of the high-voltage cable 3.

In this embodiment, the gas component collecting unit includes H₂Sensor, CO₂Sensors and ethylene oxide Sensors, H₂Sensor, CO₂The output ends of the sensor and the ethylene oxide sensor are respectively connected with the defect detection unit 2. In addition, H is₂Sensor, CO₂The sensor and the ethylene oxide sensor are both existing sensors, and the type with the precision required by the hidden defect detection of the high-voltage cable can be selected according to the requirement.

As shown in FIG. 2, the defect detecting unit 2 includes a signal processing module 21, a microprocessor 22, a wireless communication module 23 and an energy supply module 24, H₂Sensor, CO₂The output ends of the sensor and the ethylene oxide sensor are respectively connected with a microprocessor 22 through a signal processing module 21, the microprocessor 22 is connected with a wireless communication module 23, and an energy supply moduleThe outputs of block 24 are respectively connected to H₂Sensor, CO₂The sensors, the ethylene oxide sensor, the signal processing module 21, the microprocessor 22 and the power supply terminal of the wireless communication module 23 are connected.

In this embodiment, the signal processing module 21 is a filtering and amplifying circuit, and is configured to reduce signal interference and improve a signal-to-noise ratio of the acquired signal. Since the filter amplifying circuit is a conventional circuit, its specific circuit structure will not be described in detail here.

In this embodiment, the microprocessor 22 is implemented by an MCU.

In this embodiment, the wireless communication module 23 is a 4G communication module, and in addition, a WiFi module, other mobile communication modules or an internet of things wireless communication module may also be adopted as required.

In this embodiment, the energy supply module 24 is powered by a solar battery and a storage battery, the solar battery charges the storage battery through the charging circuit, and the storage battery directly provides power supply output. In order to improve the power supply performance, a small-sized wind power generation module, an induction power-taking module (for performing induction power-taking from a power transmission line), and the like may be further added as necessary.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-readable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein. The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks. These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks. These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments, and all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention. It should be noted that modifications and embellishments within the scope of the invention may occur to those skilled in the art without departing from the principle of the invention, and are considered to be within the scope of the invention.