Portable cable defect rapid diagnosis device

Abstract

The utility model discloses a portable cable defect rapid diagnosis device which comprises a hand-held detection box, a circuit control board arranged in the hand-held detection box, and a current interface arranged on the hand-held detection box and connected with a main core current CT coil and a sheath current CT coil. The circuit control board is arranged on the portable detection box, the voltage interface is arranged on the portable detection box and is externally connected with a power supply coil, a data communication coil and a sheath induction voltage coil, the battery is arranged in the portable detection box and is connected with the circuit control board, and the display screen is arranged on the portable detection box and is connected with the circuit control board. And the current interface and the voltage interface are electrically connected with the circuit control board. Through the scheme, the cable defect detection device has the advantages of simple structure, reliability in detection and the like, and has very high practical value and popularization value in the technical field of cable defect detection.

Description

Technical Field

[0001] The utility model relates to the technical field of cable defect detection, in particular to a portable cable defect rapid diagnosis device. Background Art

[0002] The cable defect rapid diagnosis device of this technology is used for defect diagnosis of the sheath of power transmission cables. The function of the cable sheath is to protect the insulation from mechanical damage and damage caused by various environmental factors (such as water, sunlight, organisms, fire, etc.) during the laying and operation process, so as to ensure the long-term stable electrical performance of the cable. Common sheath structures include inner sheath and outer sheath. Among them, the inner sheath is a protective covering layer wrapped on the cable insulation to prevent the insulation layer from moisture, mechanical damage, light and chemical corrosive media, etc., and short-circuit current can also flow through. The inner sheath includes metal sheath, flat aluminum sheath, corrugated aluminum sheath, copper sheath, composite sheath, non-metallic plastic sheath, rubber sheath, etc. In addition, the outer sheath of the cable is mainly composed of an inner lining layer, an armor layer and an outer layer. The protective covering layer wrapped outside the cable sheath (inner sheath) mainly plays a role in mechanical reinforcement and corrosion protection.

[0003] During the laying and service of cables, factors such as incorrect construction, environmental corrosion, external force damage and self-quality problems can lead to defects in the sheath grounding system of high-voltage cables. As the service time increases, defects in the sheath grounding system can induce main insulation failures of power cable lines and even cause fires and explosions in cable channels. At present, traditional methods for diagnosing cable sheath defects mainly include: infrared temperature measurement, partial discharge test, X-ray test and power-off sheath withstand voltage test. Among them, the infrared temperature measurement method can only intuitively reflect the temperature of the cable surface, and the diagnostic effect is extremely limited. The partial discharge test method does not produce discharge phenomena for most sheath grounding system defects, so it is difficult to diagnose multiple types of defects. The X-ray test method uses X-rays to determine the structural defects of the sheath. The actual operation steps of this method are complicated and the testing cost is high. Finally, the power-off sheath withstand voltage test method cannot realize online diagnosis of the cable sheath grounding system, and the detection efficiency is low.

[0004] Therefore, there is an urgent need to propose a portable cable defect rapid diagnosis device with simple structure and reliable detection. Utility Model Content

[0005] In view of the above problems, the purpose of the present invention is to provide a portable cable defect rapid diagnosis device. The technical solution adopted by the present invention is as follows:

[0006] A portable cable defect rapid diagnosis device, with a main core current CT coil, a sheath current CT coil and a sheath induction voltage coil of an external cable, comprising a portable detection box, a circuit control board arranged in the portable detection box, a current interface arranged on the portable detection box and connected to the main core current CT coil and the sheath current CT coil, a voltage interface arranged on the portable detection box and externally connected to power supply, data communication and the sheath induction voltage coil, a battery arranged in the portable detection box and connected to the circuit control board, and a display screen arranged on the portable detection box and connected to the circuit control board; the current interface and the voltage interface are electrically connected to the circuit control board;

[0007] The circuit control board includes a microcontroller U22, an SD card interface circuit, a display interface circuit, a Type-C interface circuit, a 4G communication interface circuit, a Lora interface circuit and a Bluetooth interface circuit connected to the microcontroller U22, a wireless communication module U1 connected to the 4G communication interface circuit, a SIM communication module connected to the wireless communication module U1, a bidirectional voltage level converter U4 connected to the wireless communication module U1, a communication interface connected to the bidirectional voltage level converter U4, and a DC power supply circuit connected to the microcontroller U22, the SD card interface circuit, the display interface circuit, the Type-C interface circuit, the 4G communication interface circuit, the Lora interface circuit, the Bluetooth interface circuit, the wireless communication module U1, the SIM communication module, the bidirectional voltage level converter U4 and the communication interface; the current interface and the voltage interface are connected to the microcontroller U22, and transmit current signals of the main core current CT coil and the sheath current CT coil; the communication interface is connected to the sheath induction voltage coil, and transmits the induction voltage signal.

[0008] Furthermore, the microcontroller U22 is STM32H743IIT6.

[0009] Furthermore, the wireless communication module U1 is EC800G-CN.

[0010] Furthermore, the bidirectional voltage level converter U4 is TXS0108EPWR.

[0011] Furthermore, the DC power supply circuit includes a leakage current prevention circuit connected to the battery, a voltage conversion interface circuit connected to the leakage current prevention circuit, an optocoupler circuit connected to the voltage conversion interface circuit, and a power interface circuit connected to the optocoupler circuit.

[0012] Compared with the prior art, the utility model has the following beneficial effects:

[0013] (1) The utility model collects the current information of the main core current CT coil and the sheath current CT coil, as well as the induced voltage signal of the sheath induced voltage coil, and uses the microcontroller U22 to store, diagnose, calculate and display, and uses the 4G communication interface circuit, the Lora interface circuit and the Bluetooth interface circuit for communication transmission.

[0014] (2) The utility model obtains the induced voltage signal of the cable sheath by setting a bidirectional voltage level converter U4 and a communication interface.

[0015] (3) The utility model sets a leakage current prevention circuit, performs power supply switching and prevents leakage current; in addition, the utility model sets an optical coupling circuit to realize the opening and closing of the power interface circuit, and closes the unused coil before sleep.

[0016] In summary, the utility model has the advantages of simple structure and reliable detection, and has high practical value and promotion value in the field of cable defect detection technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope of protection. For those skilled in the art, other relevant drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 This is a schematic diagram of the appearance structure of the utility model.

[0019] Figure 2 This is a schematic diagram of the first part of the microcontroller of the present invention.

[0020] Figure 3 This is a schematic diagram of the second part of the microcontroller of the present invention.

[0021] Figure 4 This is a schematic diagram of the debugging interface of the utility model.

[0022] Figure 5 This is the schematic diagram of the Bluetooth interface circuit of the utility model.

[0023] Figure 6 This is a schematic diagram of the 4G communication interface circuit of the utility model.

[0024] Figure 7 This is the schematic diagram of the Lora interface circuit of the utility model.

[0025] Figure 8 This is the schematic diagram of the induction voltage interface circuit of the utility model.

[0026] Fig. 9 This is the principle diagram of the main core current CT coil interface circuit of the utility model.

[0027] Fig.10 This is the principle diagram of the sheath current CT coil interface circuit of the utility model.

[0028] Fig.11 This is the schematic diagram of the comprehensive ground current interface circuit of the utility model.

[0029] Fig.12 This is the principle diagram of the main core CT coil interface circuit of the utility model.

[0030] Fig.13 This is the schematic diagram of the SD card interface circuit of the utility model.

[0031] Fig.14 This is a schematic diagram of the Type-C interface circuit of the utility model.

[0032] Fig.15 This is a schematic diagram of the first part of the wireless communication module U1 of the present invention.

[0033] Fig.16 This is a schematic diagram of the second part of the wireless communication module U1 of the present invention.

[0034] Fig.17 This is a schematic diagram of the third part of the wireless communication module U1 of the present invention.

[0035] Fig.18 This is a schematic diagram of the SIM communication module of the present utility model.

[0036] Fig.19 This is a schematic diagram of the communication interface of the utility model.

[0037] Fig. 20 This is a schematic diagram of a bidirectional voltage level converter U4 of the present utility model.

[0038] Fig.21 This is a schematic diagram of the power interface circuit of the utility model.

[0039] Fig. 22 This is a schematic diagram of the voltage conversion interface circuit of the utility model.

[0040] Fig.23 This is a schematic diagram of an optocoupler circuit of the utility model.

[0041] Fig.24 This is a schematic diagram of a leakage current prevention circuit of the utility model.

[0042] Fig.25This is a schematic diagram of the display interface circuit of the utility model.

[0043] Fig.26 This is the wiring diagram of the coaxial measurement mode of the utility model.

[0044] Fig. 27 This is the wiring diagram of the continuous piece measurement mode of the utility model.

[0045] Fig.28 This is the wiring diagram of the horn measurement mode of the utility model.

[0046] In the above drawings, the component names corresponding to the reference numerals are as follows:

[0047] 1. Portable testing box; 2. Current interface; 3. Voltage interface; 4. Circuit control board; 5. Display screen. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical scheme and advantages of this application clearer, the utility model is further described below in conjunction with the accompanying drawings and embodiments, and the implementation methods of this utility model include but are not limited to the following embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0049] In this embodiment, the term "and / or" is merely a term used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent three situations: A exists alone, A and B exist at the same time, and B exists alone.

[0050] The terms "first" and "second" in the description and claims of this embodiment are used to distinguish different objects rather than to describe a specific order of objects. For example, a first target object and a second target object are used to distinguish different target objects rather than to describe a specific order of target objects.

[0051] In the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0052] In the description of the embodiments of the present application, unless otherwise specified, the meaning of "multiple" refers to two or more than two. For example, multiple processing units refer to two or more processing units; multiple systems refer to two or more systems.

[0053] like Figures 1 to 28As shown, this embodiment provides a portable cable defect rapid diagnosis device, which is externally connected to the main core current CT coil, sheath current CT coil and sheath induction voltage coil of the cable. Figure 26 to Figure 28 As shown, the installation requirements of the main core current CT are as follows: (1) The direction of the main core current CT is stipulated as the head end to the end end; (2) For the sheath grounding box of the independent grounding terminal and the protective grounding terminal, when it is the head end of the interval, the main core current CT should be set on the end end side. Similarly, when it is the end of the interval, the main core current CT should be set on the head end side. (3) For the sheath grounding box of the common grounding terminal and the cross-connected terminal, two measurement methods of the main core current CT on the head end side and the end end side can be provided according to the on-site conditions. In addition, the installation requirements of the sheath current CT are as follows: (1) For the sheath grounding box of the independent grounding terminal, the protective grounding terminal, and the common grounding terminal, the direction of the sheath current CT is stipulated as the joint towards the grounding box. (2) For the cross-connected sheath grounding box, the R-phase sheath CT is uniformly installed on the main grounding wire, and the CT direction is stipulated as the grounding box towards the earth. At the same time, this system can provide 3 different measurement modes, namely coaxial, horn, and connected.

[0054] Among them, in the coaxial measurement mode: A, B, C sheath CTs are respectively installed on the coaxial grounding wires of the A, B, C phases of the cross-connected grounding box, and the direction of the sheath CT is the direction of the joint toward the grounding box. In addition, in the continuous piece measurement mode: A, B, C sheath CTs are respectively installed on the continuous pieces of A→B, B→C, C→A of the cross-connected grounding box. In the horn measurement mode: at the 1# cross-connection, the A, B, C sheath CTs are respectively installed on the single-core grounding wires of the A, B, C phases of the horn toward the head end; at the 2# cross-connection, the A, B, C sheath CTs are respectively installed on the single-core grounding wires of the A, B, C phases of the horn toward the end end.

[0055] Specifically, the portable cable defect rapid diagnosis device of this embodiment includes a portable detection box 1, a circuit control board 4 arranged in the portable detection box 1, a current interface 2 arranged on the portable detection box 1 and connected to the main core current CT coil and the sheath current CT coil, a voltage interface 3 arranged on the portable detection box 1 and externally connected to the power supply, data communication and sheath induction voltage coil, a battery arranged in the portable detection box 1 and connected to the circuit control board 4, and a display screen 5 arranged on the portable detection box 1 and connected to the circuit control board 4. Among them, the current interface 2 and the voltage interface 3 are electrically connected to the circuit control board 4. This embodiment measures the ground loop current and induced voltage of the cable sheath by externally connecting the main core current CT coil (i.e., the main core current sensor), the sheath current CT coil (i.e., the sheath current sensor) and the sheath induction voltage coil (sheath voltage sensor) to replace the measurement method of the traditional clamp ammeter, and can carry out diagnosis and analysis of various defects of the sheath under power, thereby improving the efficiency of cable operation and maintenance. This embodiment can be equipped with a diagnostic terminal, which communicates wirelessly with the circuit control board 4 to complete the collection, storage and analysis of measurement data, and realize the diagnosis of multiple types of sheath defects such as sheath protector breakdown, sheath grounding fault, sheath phase short circuit, sheath connection reverse, sheath grounding resistance is too large, sheath contact resistance is too large, etc. It should be noted that the process of calculating and analyzing based on the collected main core current, sheath current and sheath induced voltage is a mature technical means, which will not be repeated here.

[0056] In this embodiment, the circuit control board 4 includes a microcontroller U22, an SD card interface circuit, a display interface circuit, a Type-C interface circuit, a 4G communication interface circuit, a Lora interface circuit and a Bluetooth interface circuit connected to the microcontroller U22, a wireless communication module U1 connected to the 4G communication interface circuit, a SIM communication module connected to the wireless communication module U1, a bidirectional voltage level converter U4 connected to the wireless communication module U1, a communication interface connected to the bidirectional voltage level converter U4, and a DC power supply circuit connected to the microcontroller U22, the SD card interface circuit, the display interface circuit, the Type-C interface circuit, the 4G communication interface circuit, the Lora interface circuit, the Bluetooth interface circuit, the wireless communication module U1, the SIM communication module, the bidirectional voltage level converter U4 and the communication interface. In this embodiment, the current interface 2 and the voltage interface 3 are connected to the microcontroller U22, and transmit the current signals of the main core current CT coil and the sheath current CT coil; in addition, the communication interface is connected to the sheath induction voltage coil, and transmits the induction voltage signal.

[0057] In this embodiment, the DC power supply circuit includes a leakage current prevention circuit connected to the battery, a voltage conversion interface circuit connected to the leakage current prevention circuit, an optocoupler circuit connected to the voltage conversion interface circuit, and a power interface circuit connected to the optocoupler circuit. Before sleep, the optocoupler circuit is used to turn off the voltage conversion of the power interface circuit to stop the power supply to the external sensor.

[0058] The above embodiments are only preferred embodiments of the present utility model and are not intended to limit the protection scope of the present utility model. Any changes that adopt the design principles of the present utility model and are made through non-creative labor on this basis should fall within the protection scope of the present utility model.

Claims

1. A portable cable defect rapid diagnosis device, externally connected to the main core current CT coil, sheath current CT coil and sheath induction voltage coil of the cable, characterized in that: The portable detection box comprises a portable detection box (1), a circuit control board (4) arranged in the portable detection box (1), a current interface (2) arranged on the portable detection box (1) and connected to the main core current CT coil and the sheath current CT coil, a voltage interface (3) arranged on the portable detection box (1) and externally connected to power supply, data communication and sheath induction voltage coil, a battery arranged in the portable detection box (1) and connected to the circuit control board (4), and a display screen (5) arranged on the portable detection box (1) and connected to the circuit control board (4); the current interface (2) and the voltage interface (3) are electrically connected to the circuit control board (4); The circuit control board (4) comprises a microcontroller U22, an SD card interface circuit, a display interface circuit, a Type-C interface circuit, a 4G communication interface circuit, a Lora interface circuit and a Bluetooth interface circuit connected to the microcontroller U22, a wireless communication module U1 connected to the 4G communication interface circuit, a SIM communication module connected to the wireless communication module U1, a bidirectional voltage level converter U4 connected to the wireless communication module U1, a communication interface connected to the bidirectional voltage level converter U4, and a DC power supply circuit connected to the microcontroller U22, the SD card interface circuit, the display interface circuit, the Type-C interface circuit, the 4G communication interface circuit, the Lora interface circuit, the Bluetooth interface circuit, the wireless communication module U1, the SIM communication module, the bidirectional voltage level converter U4 and the communication interface; the current interface (2) and the voltage interface (3) are connected to the microcontroller U22 and transmit current signals of the main core current CT coil and the sheath current CT coil; the communication interface is connected to the sheath induction voltage coil and transmits the induction voltage signal.

2. A portable cable defect rapid diagnosis device according to claim 1, characterized in that: The microcontroller U22 is STM32H743IIT6.

3. A portable cable defect rapid diagnosis device according to claim 1 or 2, characterized in that: The wireless communication module U1 is EC800G-CN.

4. A portable cable defect rapid diagnosis device according to claim 1 or 2, characterized in that: The bidirectional voltage level converter U4 is TXS0108EPWR.

5. A portable cable defect rapid diagnosis device according to claim 1, characterized in that: The DC power supply circuit includes a leakage current prevention circuit connected to a battery, a voltage conversion interface circuit connected to the leakage current prevention circuit, an optocoupler circuit connected to the voltage conversion interface circuit, and a power interface circuit connected to the optocoupler circuit.

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