Instrument for contact detection of insulator defects of drop-out fuse

Abstract

The invention relates to an instrument for contact detection of insulator defects of a drop-out fuse. The instrument judges whether the drop-out fuse insulator has defects or not through bundled heating, temperature measurement and comparison between the change rule of the difference between the temperature of a breakable point and the environment temperature and the change rule of the difference without defects. Comprising a flexible heating sheet, a strip-shaped flexible material, a heating element, a film temperature sensor, a first FPC flat cable connector and a second FPC flat cable connector. And the device can be recycled after a measurement result is waited, so that the occupied time of personnel is reduced. The structure is simple, use is efficient, and measurement is accurate.

Description

Technical Field

[0001] The present invention relates to electrical equipment detection technology, and in particular to a contact detection instrument for judging the defect of a drop-out fuse insulator based on whether the heat transfer process of the insulator is normal, and belongs to the field of power system monitoring. Background Art

[0002] Drop-out fuses are vital overload protection devices in power systems. Their core function is to quickly cut off the circuit when the current exceeds the set value to ensure the safety of equipment and circuits. However, in Northwest my country, frequent strong winds and significant temperature differences between day and night pose a severe challenge to the reliability of fuses. Drop-out fuses are mainly composed of insulators, fixed ends, fuse tubes, inlet / outlet terminals, and moving / static contacts. As an important component of the fuse, the insulator not only supports the entire device, but also performs an insulating function. Its structural characteristics make the connection between the fixed end and the insulator a weak link where stress is concentrated, which can easily lead to fuse failure, resulting in serious economic losses and waste of resources.

[0003] The failure of porcelain insulators may be manifested as porcelain body fracture, cement adhesive swelling due to moisture absorption, or cement adhesive being squeezed out of the jelly-like holes in the porcelain bottle when the insulator is subjected to large stress but not broken. In either case, the connection between the fixed end and the insulator will eventually loosen and fail. In the early stage of failure, this looseness may be very hidden and difficult to detect with the naked eye, so it is necessary to design a special instrument to detect the contact status of the two parts.

[0004] As a commonly used protective device in power systems, the health of the insulators of drop-out fuses is crucial to the safety of the entire system. Traditional detection methods often rely on ultrasonic detection, ultraviolet imaging detection and other methods, which have many operational restrictions and low detection efficiency. Therefore, the development of a high-precision detection instrument has become an inevitable demand. Summary of the invention

[0005] The object of the present invention is to provide an instrument capable of accurately detecting defects of insulators of drop-out fuses in a contact manner, based on the fact that defects of the insulators (such as cracks at any part) change the heat transfer process of the insulators, so that under the same specified heating conditions, the law of the temperature difference between a specified point and the ambient temperature is different from that when there are no defects, and then the presence or absence of defects in the insulator is judged based on this difference in degree.

[0006] The technical solution of the present invention is as follows: an instrument for contact detection of insulator defects of a drop-out fuse is designed, wherein a flexible heating sheet is designed, wherein the flexible heating sheet has at least two layers of strip-shaped flexible materials, wherein a heating element and a thin film temperature sensor are arranged in the interlayer of the strip-shaped flexible materials, wherein the flexible heating sheet is attached to a binding structure, wherein the binding structure is connected with a first FPC cable connector and a second FPC cable connector, wherein the thin film temperature sensor is electrically connected to the second FPC cable connector, wherein the heating element is electrically connected to the first FPC cable connector, wherein the first FPC cable connector is used to connect a power source, wherein the second FPC cable connector is used to transmit temperature data, wherein the flexible heating sheet is used to contact and heat the iron handle position After the two ends of the bundling structure are connected, the flexible heating sheet wraps around the cylindrical position of the heating iron handle. At the same time, the temperature of the heating iron handle position is measured by a thin film temperature sensor to obtain the temperature variation law of the difference between the measured temperature and the ambient temperature. The temperature variation law data is transmitted to the data processor via the second FPC cable connector. The obtained temperature variation law is compared with the preset temperature variation law of the difference between the heating iron handle position temperature and the ambient temperature obtained when the drop-out fuse is subjected to the same heating conditions when the insulator is not defective. The conformity of the two temperature variation laws is compared. When the conformity exceeds the design specified conformity, it is determined that the drop-out fuse insulator has defects.

[0007] The data processor is an intermediate connection device or a host computer. The intermediate connection device is provided with a first FPC interface, a second FPC interface, a built-in battery, a chip and a memory, and a USB interface. The first FPC interface is connected to the built-in battery, the second FPC interface is connected to the chip and the memory, the chip and the memory are connected to the USB interface, and the second FPC interface is used to connect to the second FPC cable connector to transmit temperature change law data to the chip and the memory. After the measured temperature change law data is calculated by the chip and the memory, the calculation result is connected to the host computer through the USB interface to directly view the result. Another way is to store it in a memory card first, and then connect to the host computer through the USB interface to view the result after a period of time.

[0008] Preferably, the binding structure is a nylon strap and a buckle, a Velcro hook surface and a Velcro fleece surface, the flexible heating sheet is pasted on the surface of the nylon strap, the buckle is connected to one end of the nylon strap, the Velcro hook surface and the Velcro fleece surface are respectively on both sides of the nylon strap, the flexible heating sheet, nylon strap and Velcro form a multi-layer structure, and the joint surfaces are bonded with hot melt adhesive.

[0009] The strip-shaped flexible material is a polyimide film, the heating element is a nickel-chromium heating wire, and the film temperature sensor adopts a T-type thermocouple.

[0010] Furthermore, a plurality of T-type thermocouples are arranged and distributed equidistantly to measure the average temperature of the position covered by the flexible heating sheet.

[0011] The heating element and the thin film temperature sensor are on one side of the nylon tape, and the first FPC cable connector and the second FPC cable connector are on the other side of the nylon tape. The wire passes through the gap of the nylon tape to connect the thin film temperature sensor and the second FPC cable connector, and the heating element and the first FPC cable connector respectively.

[0012] The beneficial effects of the present invention are as follows: by bundling heating and temperature measurement, and then comparing the temperature difference change law with the preset temperature difference change law, the degree of compliance can be obtained, and then it can be judged whether the insulator is defective. After bundling, no human supervision is required, and the device can be recovered after the measurement result is obtained, which reduces the time occupied by personnel. The structure is simple, the use is efficient, and the measurement is accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 The overall structure of the instrument is shown; Figure 2 The use process of the instrument is shown; Figure 3 Demonstrated the module interactions during the detection process; Figure 4 The temperature variation law preset by the instrument (dashed line) and the temperature variation law detected (solid line) are shown; Figure 5 Shows the installation location of the instrument. DETAILED DESCRIPTION

[0014] An instrument for contact detection of insulator defects of a drop-out fuse is designed, wherein a flexible heating sheet 2 is designed, wherein the flexible heating sheet 2 has at least two layers of strip-shaped flexible materials, wherein a heating element and a thin film temperature sensor 4 are arranged in the interlayer of the strip-shaped flexible materials, wherein the flexible heating sheet 2 is attached to a binding structure, wherein the binding structure is connected with a first FPC cable connector 16 and a second FPC cable connector 17, wherein the thin film temperature sensor 4 is electrically connected to the second FPC cable connector 17, wherein the heating element is electrically connected to the first FPC cable connector 16, wherein the first FPC cable connector 16 is used to connect a power source, wherein the second FPC cable connector 17 is used to transmit temperature data, wherein the flexible heating sheet 2 is used to contact and heat an iron handle position 3 After the two ends of the bundling structure are connected, the flexible heating sheet 2 wraps around the cylindrical position 3 of the heating iron handle, and the thin film temperature sensor 4 is used to measure the temperature of the heating iron handle position 3, and the temperature change law of the difference between the measured temperature and the ambient temperature is obtained. The temperature change law data is transmitted to the data processor through the second FPC cable connector 17, and the obtained temperature change law is compared with the preset temperature change law of the difference between the temperature of the heating iron handle position 3 and the ambient temperature obtained when the drop-out fuse is subjected to the same heating conditions when the insulator is not defective, and the compliance of the two temperature change laws is compared. When the compliance exceeds the design compliance, it is determined that the drop-out fuse insulator 11 is defective.

[0015] The data processor is an intermediate connection device 18 or a host computer. The intermediate connection device 18 is provided with a first FPC interface 19, a second FPC interface 20, a built-in battery 21, a chip and a memory 22, and a USB interface 23. The first FPC interface 19 is connected to the built-in battery 21, the second FPC interface 20 is connected to the chip and the memory 22, the chip and the memory 22 are connected to the USB interface 23, and the second FPC interface 20 is used to connect to the second FPC cable connector 17 to transmit temperature change law data to the chip and the memory 22. After the measured temperature change law data is calculated by the chip and the memory 22, the calculation result is connected to the host computer 24 through the USB interface 23 to directly view the result. Another way is to store it in a memory card first, and then connect to the host computer 24 through the USB interface 23 to view the result after a period of time.

[0016] Preferably, the binding structure is a nylon strap 12 and a buckle 13, a Velcro hook surface 14 and a Velcro fleece surface 15, the flexible heating sheet 2 is pasted on the surface of the nylon strap 12, the buckle 13 is connected to one end of the nylon strap 12, the Velcro hook surface 14, the Velcro fleece surface 15, the flexible heating sheet 2 and the nylon strap 12 form a multi-layer structure 29, and the joint surfaces are bonded using hot melt adhesive.

[0017] The strip-shaped flexible material is a polyimide film 25, which serves as an insulating medium. The heating element is a nickel-chromium heating wire 26, and the film temperature sensor 4 can be a T-type thermocouple 27, or other temperature measuring elements.

[0018] Furthermore, a plurality of T-type thermocouples 27 are arranged and distributed at equal intervals to measure the average temperature of the position covered by the flexible heating sheet 2 .

[0019] The heating element and the thin film temperature sensor 4 are on one side of the nylon tape 12, and the first FPC cable connector 16 and the second FPC cable connector 17 are on the other side of the nylon tape. The wires pass through the gaps in the nylon tape to connect the thin film temperature sensor 4 and the second FPC cable connector 17, and the heating element and the first FPC cable connector 16, respectively.

[0020] The instrument is firmly fixed to the cylindrical position 3 of the iron handle of the drop-out circuit breaker using a nylon strap 12 and a buckle 13, in combination with a Velcro hook surface 14 and a Velcro fleece surface 15. This design ensures that it is stable and does not shift during the heating and measurement process, thereby ensuring the accuracy of the data. The temperature difference between the cylindrical position of the iron handle and the ambient temperature under the specified heating conditions when the insulator is preset to be defect-free is recorded. This law is to use a flexible heating sheet at a specified position for contact heating with a specific heat flux, and then record the change of the temperature difference between the breakable point and the ambient temperature over time. During the test, by comparing the actual measured temperature difference change law with the preset temperature difference change law, when the compliance exceeds the set value, it can be judged that the insulator has defects.

[0021] The intermediate connection device 18 is connected to the host computer 24 via a USB interface for detailed data analysis and report generation.

[0022] The above components form a multi-layer structure to ensure reasonable layout and clear functions.

[0023] First layer: the heating element and the thin film temperature sensor 4 are covered between two layers of the strip-shaped flexible material, and the Velcro hook surface 14 is next to the strip-shaped flexible material; The second layer: nylon binding tape 12, which is the main structure to bear the binding force; the first FPC cable connector 16 and the second FPC cable connector 17 are connected to the nylon binding tape 12 by means of hinges (the hinges are made into one piece with the FPC cable connector housing) and rivets, or by means of connecting rings (the connecting rings are made into one piece with the FPC cable connector housing) and wrapping a cloth strip around it, and the cloth strip is then connected to the nylon binding tape 12 by sewing; The third layer: the Velcro fleece surface 15 is attached to the surface of the nylon strap 12 (the opposite side to the flexible heating sheet) as an outer layer to provide additional structural support.

[0024] Bonding: Hot melt adhesive is used to fix each layer to enhance the stability and durability of the overall equipment.

[0025] Operation method: 1. Installation: Fix the instruments to the iron handle of the drop-out fuse in order.

[0026] 2. Start heating: Turn on the flexible heating sheet and start applying heat flux.

[0027] 3. Temperature measurement and data processing: Acquire temperature data in real time, and process, store and send it through the intermediate connection device 18.

[0028] 4. Data analysis: By comparing the stored and real-time acquired temperature change data, the health status of the drop-out fuse insulator can be determined.

Claims

1. An instrument for contact detection of insulator defects of drop-out fuses, characterized in that: A flexible heating sheet (2) is designed. The flexible heating sheet (2) has at least two layers of strip-shaped flexible material. A heating element and a thin film temperature sensor (4) are arranged in the interlayer of the strip-shaped flexible material. The flexible heating sheet (2) is attached to a binding structure. The binding structure is connected to a first FPC cable connector (16) and a second FPC cable connector (17). The thin film temperature sensor (4) is electrically connected to the second FPC cable connector (17). The heating element is electrically connected to the first FPC cable connector (16). The first FPC cable connector (16) is used to connect to a power source. The second FPC cable connector (17) is used to transmit temperature data. The flexible heating sheet (2) contacts the heating iron handle position (3). The binding structure After the two ends of the structure are connected, the flexible heating sheet (2) wraps around the cylindrical position (3) of the heating iron handle, and at the same time, the temperature of the heating iron handle position (3) is measured by a thin film temperature sensor (4) to obtain a temperature variation law of the difference between the measured temperature and the ambient temperature. The temperature variation law data is transmitted to a data processor via a second FPC cable connector (17). The obtained temperature variation law is compared with a preset temperature variation law of the difference between the temperature of the heating iron handle position (3) and the ambient temperature obtained when the drop-out fuse is subjected to the same heating conditions when the insulator is not defective. The conformity of the two temperature variation laws is compared. When the conformity exceeds the conformity specified in the design, it is determined that the drop-out fuse insulator (11) has a defect.

2. The instrument for contact detection of insulator defects of drop-out fuses according to claim 1 is characterized in that: The data processor is an intermediate connection device (18) or a host computer. The intermediate connection device (18) is provided with a first FPC interface (19), a second FPC interface (20), a built-in battery (21), a chip and a memory (22), and a USB interface (23). The first FPC interface (19) is connected to the built-in battery (21), the second FPC interface (20) is connected to the chip and the memory (22), the chip and the memory (22) are connected to the USB interface (23), and the second FPC interface (20) is used to connect to the second FPC cable connector (17) to transmit temperature change law data to the chip and the memory (22). After the measured temperature change law data is calculated by the chip and the memory (22), the calculation result is connected to the host computer (24) through the USB interface (23) to directly view the result. Another method is to first store it in a memory card and then connect it to the host computer (24) through the USB interface (23) to view the result after a period of time.

3. An instrument for contact detection of insulator defects of drop-out fuses according to claim 1 or 2, characterized in that: The binding structure comprises a nylon strap (12) and a buckle (13), a Velcro hook surface (14) and a Velcro fleece surface (15); the flexible heating sheet (2) is adhered to the surface of the nylon strap (12); the buckle (13) is connected to one end of the nylon strap (12); the Velcro hook surface (14) and the Velcro fleece surface (15) are respectively on the two sides of the nylon strap (12); the flexible heating sheet (2), the nylon strap (12) and the Velcro form a multi-layer structure (29); and the joint surfaces are bonded using hot melt adhesive.

4. An instrument for contact detection of insulator defects of drop-out fuses according to claim 1 or 2, characterized in that: The strip-shaped flexible material is a polyimide film (25), the heating element is a nickel-chromium heating wire (26), and the film temperature sensor (4) uses a T-type thermocouple (27).

5. The instrument for contact detection of insulator defects of drop-out fuses according to claim 4, characterized in that: A plurality of T-type thermocouples (27) are arranged at equal intervals to measure the average temperature of the location covered by the flexible heating sheet (2).

6. The instrument for contact detection of insulator defects of drop-out fuses according to claim 3, characterized in that: The heating element and the thin film temperature sensor (4) are on one side of the nylon binding tape (12), and the first FPC cable connector (16) and the second FPC cable connector (17) are on the other side of the nylon binding tape. The wires pass through the gaps in the nylon binding tape to respectively connect the thin film temperature sensor (4) and the second FPC cable connector (17), and the heating element and the first FPC cable connector (16).

Images