Resonant temperature sensor and cable connector temperature monitoring system

Abstract

This application provides a resonant temperature sensor and a cable joint temperature monitoring system. The sensor includes a dielectric plate, a first metal sheet, a second metal sheet, and an induction coil. The first metal sheet is attached to the upper surface of the dielectric plate, and the second metal sheet is attached to the lower surface of the dielectric plate, with the first and second metal sheets facing each other. The first metal sheet, the second metal sheet, and the dielectric plate together constitute a capacitor. One end of the induction coil is connected to the first metal sheet. The dielectric plate is made of ethylene vinyl acetate copolymer with added PZT piezoelectric ceramic powder and nano-metal particles. This material itself has a sufficiently large dielectric constant and temperature coefficient, which can generate additional capacitance on the basis of the dielectric. Furthermore, the flexible material allows it to be directly embedded inside the cable joint to directly measure the temperature of the conductor, solving the problem of not being able to directly and accurately measure the temperature of the cable joint in a small, enclosed space.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of temperature measurement, in particular to a resonant temperature sensor and a cable joint temperature monitoring system. BACKGROUND

[0002] Although the existing temperature sensor device can realize the monitoring of temperature, the temperature sensor cannot realize the temperature measurement of special scenes in many specific environments and scenes due to the design of the wireless and passive sensor, thereby resulting in the untimely, inaccurate measurement of temperature, the short service life of the equipment and the inconvenience of maintenance and disassembly.

[0003] For example, the biggest limitation of the distributed optical fiber in the application scene of cable temperature measurement is that it can only measure the temperature outside the cable, which leads to two serious problems: 1) the temperature measurement point is outside the cable, and the temperature inside the cable needs to be inversely calculated by an algorithm, and the accuracy of the result is greatly affected by external factors such as environment, and it is difficult to accurately reflect the temperature inside the cable; 2) because the temperature measurement point is outside the cable, it cannot reflect the abnormal situation inside the cable in time, which causes serious delay for early warning and fault handling. SUMMARY

[0004] The main purpose of the present application is to provide a resonant temperature sensor and a cable joint temperature monitoring system to solve the problem that the distributed optical fiber temperature measurement in the prior art cannot realize real-time monitoring of the temperature inside the cable.

[0005] According to one aspect of the embodiment of the present application, a resonant temperature sensor and a cable joint temperature monitoring system are provided, the sensor comprising a dielectric plate, a first metal sheet, a second metal sheet and an induction coil, the first metal sheet being attached to the upper surface of the dielectric plate, the second metal sheet being attached to the lower surface of the dielectric plate, and the first metal sheet and the second metal sheet being oppositely arranged, one end of the induction coil being connected with the first metal sheet; wherein the material for preparing the dielectric plate is ethylene-vinyl acetate copolymer added with PZT piezoelectric ceramic powder and nano-sized metal particles, and the resonant temperature sensor is used for monitoring the temperature inside the cable.

[0006] Further, the resonant temperature sensor is arranged outside the conductor connection pipe of the cable.

[0007] Further, the shape of the induction coil is planar spiral, the first metal sheet is located at the center position of the induction coil, and the second metal sheet is close to the outer surface of the conductor connection pipe.

[0008] Further, the resonant temperature sensor is clamped between the inner insulation layer of the cable and the conductor connection pipe.

[0009] Further, the resonant temperature sensor further comprises a protective layer, which is arranged on the upper layer of the first metal sheet and the inductive coil.

[0010] According to another aspect of the present application, a cable joint temperature monitoring system is provided, which comprises any one of the resonant temperature sensors, and further comprises a signal transceiver and a processor, the resonant temperature sensor is installed in the cable joint; the signal transceiver is installed in the surrounding area of the resonant temperature sensor, and is used for emitting an electromagnetic signal and receiving a resonance signal, wherein the inductive coil generates electromagnetic induction under the excitation of the electromagnetic signal, so that the resonant temperature sensor generates the resonance signal; the processor is electrically connected with the signal transceiver, and is used for determining the temperature inside the cable joint according to the resonance signal.

[0011] Further, the processor comprises a filtering unit, a signal amplification unit and a signal processing unit, the filtering unit is electrically connected with the signal transceiver, and is used for filtering the resonance signal to obtain a filtered resonance signal; the signal amplification unit is electrically connected with the filtering unit, and is used for amplifying the filtered resonance signal to obtain an amplified resonance signal; the signal processing unit is electrically connected with the signal amplification unit, and is used for determining the temperature inside the cable joint according to the resonance signal.

[0012] Further, the signal processing unit comprises a signal demodulation module and a signal processing module, the signal demodulation module is used for demodulating the frequency of the amplified resonance signal; the signal processing module is electrically connected with the signal demodulation module, and is used for determining the temperature inside the cable joint according to the frequency of the amplified resonance signal.

[0013] Further, the processor further comprises an analog-to-digital conversion unit, which is electrically connected with the signal amplification unit and the signal processing unit respectively, and is used for converting the amplified resonance signal into a digital signal.

[0014] Further, the cable joint monitoring system further comprises a cloud server, which communicates with the processor.

[0015] The technical scheme of the application is applied to form a capacitor by a dielectric plate, a first metal sheet and a second metal sheet, one end of an induction coil is connected to the first metal sheet, the capacitor is arranged at the center of the induction coil, the capacitor and the induction coil form an LC circuit, the material of the dielectric plate is ethylene-vinyl acetate copolymer added with PZT piezoelectric ceramic powder and nano metal particles, the dielectric constant and temperature coefficient of the material are large enough to generate additional capacitance on the basis of the dielectric, and the flexible material can be directly embedded in the cable joint and directly contact with the conductor, the corresponding relationship between the characteristic frequency of the LC resonant circuit and the temperature can be used to directly read the conductor temperature in the cable joint, and the problem that the temperature of the cable joint cannot be directly and accurately measured in a narrow and closed space is solved. BRIEF DESCRIPTION OF DRAWINGS

[0016] The accompanying drawings, which form a part of the specification, are included to provide a further understanding of the application and are incorporated herein by reference. The illustrations are shown schematically and are not intended to limit the application in any way. In the drawings:

[0017] Figure 1 A cross-sectional structure schematic diagram of a resonant temperature sensor according to an embodiment of the application is shown;

[0018] Figure 2 A structure relationship schematic diagram of an induction coil and a capacitor according to an embodiment of the application is shown;

[0019] Figure 3 A cross-sectional schematic diagram of a capacitor and an induction coil according to an embodiment of the application is shown;

[0020] Figure 4 A cable joint schematic diagram according to an embodiment of the application is shown;

[0021] Figure 5 A system block diagram of a cable joint temperature monitoring system according to an embodiment of the application is shown;

[0022] Figure 6 A signal generation and transceiver module schematic diagram according to an embodiment of the application is shown.

[0023] In the above drawings, the following reference signs are used:

[0024] 10, resonant temperature sensor; 11, LC circuit; 12, protective layer; 20, capacitor; 201, first metal sheet; 202, second metal sheet; 203, dielectric plate; 21, induction coil; 30, outer tube insulation layer; 31, inner insulation layer; 32, shielding layer; 33, conductor connecting tube; 34, outer insulation layer; 40, signal transceiver. DETAILED DESCRIPTION

[0025] It should be noted that the following detailed description is merely exemplary in nature and is intended to provide further description of the application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0026] It is also important to note that the terms "including", "containing", and / or "comprising", etc., are intended to be open-ended terms. As used herein, the singular form "a", "an" and "the" include plural references unless the context clearly dictates otherwise. As used herein, the term "or" is intended to mean either or both of whichever is desired. As used herein, "and / or" is intended to mean either or both of whichever is desired.

[0027] It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" another element, it can be directly on the other element or intervening elements can also be present. In addition, it will be understood that when an element is referred to as being "connected" to or "coupled" to another element, it can be directly connected or coupled to the other element, or intervening elements can be present.

[0028] For the convenience of description, the following describes some nouns or terms related to the embodiments of the application:

[0029] PZT: PbZrO3 and PbTiO3 solid solution.

[0030] As introduced in the background, the existing temperature sensor device cannot realize temperature measurement in many specific environments and scenarios when monitoring temperature, because the design of the sensor does not consider wireless and passive problems, thereby leading to that the measured temperature is not timely, the device is not long in use, and maintenance and disassembly are not convenient. In order to solve the problem that the distributed optical fiber temperature measurement in the prior art cannot realize monitoring of the internal temperature of the cable, the embodiments of the application provide a resonant temperature sensor and a cable joint temperature monitoring system.

[0031] According to a typical embodiment of the application, as Figure 1 and Figure 3As shown in the drawings, a resonant temperature sensor 10 is provided. The resonant temperature sensor 10 comprises a medium plate 203, a first metal sheet 201, a second metal sheet 202 and an induction coil 21, the first metal sheet 201 is attached to the upper surface of the medium plate 203, the second metal sheet 202 is attached to the lower surface of the medium plate 203, and the first metal sheet 201 and the second metal sheet 202 are arranged opposite to each other, one end of the induction coil 21 is connected with the first metal sheet 201; wherein the material for preparing the medium plate 203 is ethylene vinyl acetate copolymer added with PZT piezoelectric ceramic powder and nano metal particles, and the resonant temperature sensor 10 is used for monitoring the temperature inside the cable.

[0032] As shown in the drawings, Figure 1 , Figure 2 and Figure 3 , the first metal sheet 201, the second metal sheet 202 and the medium plate 203 together constitute a capacitor 20, one end of the induction coil 21 is connected with the first metal sheet 201, and the capacitor 20 is arranged at the center of the induction coil 21, which is helpful for the generation of resonance and facilitates the monitoring of the temperature of the cable intermediate joint, and the capacitor 20 and the induction coil 21 together constitute an LC circuit 11.

[0033] Specifically, as shown in the drawings, Figure 4 , the resonant temperature sensor 10 can be in a sheet shape, and is arranged around the conductor connecting pipe 33 during installation, which reduces the space and can be closely attached to the conductor connecting pipe 33, thereby facilitating the collection of the temperature of the cable intermediate joint.

[0034] Specifically, as shown in the drawings, Figure 2 and Figure 3 , the reason for selecting ethylene vinyl acetate copolymer added with PZT piezoelectric ceramic powder and nano metal particles as the material of the medium plate 203 is that: the piezoelectric ceramic and other materials with large rigidity are generally used in the medium of the capacitor 20, while the flexible sensor is required in the present application. And the ethylene / vinyl acetate copolymer (EVA) has the following characteristics: (1) EVA is a high polymer material, which is acceptable in cost as an industrialized raw material; (2) it has sufficient flexibility, and its Young's modulus is 42 MPa (as a comparison, the Young's modulus of the commonly used polyimide Pi material is 2.5 GPa, and the Young's modulus of aluminum is 70 Gpa), so it is soft enough to be used as a flexible substrate material; (3) it can be used as an adhesive, so it can be well bonded with the external packaging material, improving the mechanical reliability of the whole device.

[0035] Specifically, the reason for selecting PZT ceramic is that PZT ceramic is a material with very large dielectric constant, which can increase the dielectric constant of PZT-EVA composite material, and its temperature coefficient of dielectric constant is large enough.

[0036] Specifically, the reason for selecting EVA-PZT-metal nanoparticles is as follows: after the flexible sensor is prepared, it needs to be attached to the surface of the connecting pipe during installation, and the connecting pipe is arc-shaped, so deformation will inevitably occur during the attachment process. When the sensor deforms, deformation and pressure will occur in the microstructure of the material. For PZT material, in addition to its own dielectric constant and temperature coefficient being large enough, when deformation occurs, piezoelectric effect will occur, at which point charge separation will occur, that is, an additional electric field will be generated in the capacitor, so that an additional capacitance can be generated on the basis of the dielectric.

[0037] At the same time, after charge separation, the electric field will be localized and amplified under the quantum effect of metal nanoparticles. At the same time, because both PZT ceramic powder and metal nanoparticles are in the EVA polymer material, they will not undergo relative displacement, so as long as the external field does not change, the localized electric field will not shift, thereby ensuring the stability and enhancement of the additional electric field.

[0038] In the above-mentioned resonant temperature sensor, the dielectric plate, the first metal sheet, and the second metal sheet together constitute a capacitor, one end of the induction coil is connected to the first metal sheet, the capacitor is arranged at the center of the induction coil, and the capacitor and the induction coil together constitute an LC circuit. The material of the dielectric plate is ethylene-vinyl acetate copolymer added with PZT piezoelectric ceramic powder and nanoscale metal particles. The dielectric constant and temperature coefficient of this material are large enough to generate an additional capacitance on the basis of the dielectric, and the flexible material can be directly embedded in the cable joint and directly contact the conductor. By using the corresponding relationship between the characteristic frequency of the LC resonant circuit and the temperature, the temperature of the conductor inside the cable joint can be directly read, solving the problem of being unable to directly and accurately measure the temperature of the cable intermediate joint in a narrow and closed space.

[0039] In another embodiment, as shown in Figure 4As shown in the drawings, the resonant temperature sensor 10 is wound outside the conductor connecting tube 33 of the cable. Specifically, the resonant temperature sensor 10 is clamped between the inner insulation layer 31 of the cable and the conductor connecting tube 33. Specifically, the tube outer insulation layer 30 is provided between the shielding layer 32 between the inner insulation layer 31 and the outer insulation layer 34, the conductor connecting tube 33 connecting the two cable ends, and the signal transceiver 40 is provided between the outer insulation layer 34 and the tube outer insulation layer 30. The thicker insulation layer and the inner and outer shielding structure can effectively prevent electromagnetic interference. From the above description, it can be seen that the above-mentioned embodiments of the present application achieve the following technical effects: on the one hand, it can no longer need to change its structure according to the size of the shielding layer internal space, and only needs to be wound outside the conductor connecting tube, which can complete the fixation of the temperature sensor, and has better adaptability to different models of cable joints of different manufacturers; on the other hand, the wireless passive flexible temperature sensor can be closer to the conductor connecting tube, facilitating heat conduction and more accurate temperature measurement; in addition, the clamping position between the inner insulation layer and the conductor connecting tube not only has a small internal space, ensuring complete sealing and excellent composite interface electrical performance, but also has a compact internal structure of the cable intermediate joint, facilitating installation and making the temperature sensor closer to the signal transceiver of the control circuit, making the received signal more accurate.

[0040] As shown in the drawings, Figure 2 , Figure 3 and Figure 4 , the shape of the induction coil 21 is planar spiral, the first metal sheet 201 is located at the center of the induction coil 21, and the second metal sheet 202 is close to the outer surface of the conductor connecting tube 33. Specifically, the induction coil 21 is arranged in a planar spiral shape, the capacitor 20 is arranged at the center of the planar spiral induction coil 21, and the plane on which the plates of the capacitor 20 are arranged is parallel to the extension direction of the wireless passive flexible thin film temperature sensor. When the wireless passive flexible thin film temperature sensor is wound around the conductor connecting tube 33, one of the plates of the capacitor 20 can be arranged close to the conductor connecting tube 33. An intermediate medium is also provided between the two plates of the capacitor 20. The intermediate medium can be formed of a temperature-sensitive dielectric material to increase the response sensitivity of the capacitor 20 to temperature.

[0041] In another embodiment, as shown in the drawings, Figure 1 , Figure 2 and Figure 3 , the resonant temperature sensor 10 further comprises a protective layer 12, and the protective layer 12 covers the upper layer of the first metal sheet 201 and the induction coil 21. Specifically, the wireless passive flexible thin film temperature sensor can be in the form of a sheet, and the protective layer 12 also covers the surface of the second metal sheet 202 away from the dielectric plate 203.

[0042] In addition, the setting of the protective layer can prevent electromagnetic interference, and the airtight environment, i.e., the full-sealing installation can ensure complete sealing and excellent composite interface electrical performance.

[0043] Embodiments of the present application also provide a cable joint temperature monitoring system, as shown in the accompanying drawings, which comprises any one of the above-mentioned resonant temperature sensors, and further comprises a signal transceiver and a processor, the resonant temperature sensor is installed inside the cable joint; the signal transceiver is installed in the surrounding area of the resonant temperature sensor, and is used for emitting an electromagnetic signal and receiving a resonance signal, wherein the induction coil generates electromagnetic induction under the excitation of the electromagnetic signal, so that the resonant temperature sensor generates the resonance signal; the processor is electrically connected with the signal transceiver, and is used for determining the temperature inside the cable joint according to the resonance signal. Figure 5

[0044] Specifically, the system further comprises a positioning module and a GSM / GPRS module.

[0045] Specifically, the data communication between the temperature measuring device and the interactive host computer software is realized by the GSM / GPRS module through the cooperation of the SIM800C and the SIM card, the data is first transmitted to the cloud server, and then directly transmitted to the interactive host computer software through the cloud, without the need for short-distance intermediate communication means such as WiFi or Bluetooth, without the need to build a local area network, and the shortcomings of local area network communication are made up.

[0046] Specifically, the temperature measuring system further comprises an external circuit temperature and humidity monitoring system, and a DHT11 temperature and humidity sensor can be selected to realize the temperature and humidity sensing of the control circuit, i.e., the running condition of the control circuit can be known, real-time monitoring of the performance state of the temperature measuring circuit and device damage warning are realized, and the safety of the entire temperature measuring system is further ensured.

[0047] By applying the above technical solutions, the cable joint of various models can have good adaptability, and the monitoring system can realize the direct monitoring function of the cable joint temperature and the precise positioning function of the cable joint, improve the maintenance efficiency, and has the advantages of simple installation and low cost, and meets the actual operation requirements.

[0048] In another example, as shown in Figure 5 and Figure 6 ​As shown in the figure, the processor includes a filtering unit, a signal amplification unit, and a signal processing unit. The filtering unit is electrically connected to the signal transceiver, and is configured to perform filtering processing on the resonance signal to obtain a filtered resonance signal. The signal amplification unit is electrically connected to the filtering unit, and is configured to perform amplification processing on the filtered resonance signal to obtain an amplified resonance signal. The signal processing unit is electrically connected to the signal amplification unit, and is configured to determine the temperature inside the cable joint according to the resonance signal.

[0049] In a specific embodiment, as shown in the figure, Figure 6 The signal processing unit includes a signal demodulation module and a signal processing module. The signal demodulation module is configured to demodulate the frequency of the amplified resonance signal. The signal processing module is electrically connected to the signal demodulation module, and is configured to determine the temperature inside the cable joint according to the frequency of the amplified resonance signal.

[0050] In another example, as shown in the figure, Figure 6 The processor further includes an analog-to-digital conversion unit, which is electrically connected to the signal amplification unit and the signal processing unit, and is configured to convert the amplified resonance signal into a digital signal.

[0051] Specifically, an algorithm for monitoring the temperature of a cable joint is provided, a program is designed based on python, the received data is analyzed and calculated to obtain a characteristic frequency, and finally a relationship between temperature and characteristic frequency is obtained based on a series of characteristic frequencies obtained at different temperatures. The beneficial effects of the built-in temperature measurement system of the electromagnetic resonance cable intermediate joint lie in that it can realize direct measurement of the conductor temperature inside the cable joint; through the GSM / GPRS module, the SIM800C cooperates with the SIM card to realize data communication between the temperature measurement device and the interactive host computer software, the data is first transmitted to the cloud server, and then directly transmitted to the interactive host computer software through the cloud, without the need for short-distance intermediate communication means such as WiFi or Bluetooth, without the need to build a local area network, and the shortcomings of local area network communication are made up.

[0052] In a specific embodiment, as shown in the figure, Figure 5 The cable joint temperature monitoring system further includes a cloud server, which communicates with the processor.

[0053] Applying the above embodiment, the signal transceiver generates electromagnetic signals, which are amplified by the amplifier, matched with the multi-way relay and other capacitors and resistors, and then sent to the controller after simple amplification processing of the received signals; the control circuit transmits the resonant signal to the wireless passive flexible temperature sensor through the external reading coil, directly reads the internal conductor temperature of the cable joint by using the corresponding relationship between the characteristic frequency of the electromagnetic resonant loop and the temperature; selects the SIM800C8 module matched with the SIM card, directly transmits the data to the cloud server, and then directly transmits the data to the interactive host computer software through the cloud, so as to monitor the internal conductor temperature of the cable joint in real time; supplemented by the positioning module, the cable joint position is accurately positioned, which is convenient for subsequent maintenance work.

[0054] In another embodiment, in addition to monitoring the temperature of the cable and positioning the cable joint, a fault positioning device is also added.

[0055] Specifically, the positioning device is composed of a workbench and a cable monitoring device built-in Bluetooth and uwb modules. Bluetooth technology is actually a kind of short-range wireless communication technology. In simple terms, Bluetooth technology enables modern mobile communication devices and computer devices that are easy to carry to be connected without the help of cables, and can realize wireless Internet, and its actual application range can be extended to various information home appliances, consumer electronics and automobiles, etc. Information home appliances, to form a huge wireless communication network.

[0056] Specifically, the UWB technology is a wireless carrier communication technology using a frequency bandwidth of 1 GHz or more. It does not use a sinusoidal carrier, but transmits data using a nanosecond-level non-sinusoidal wave narrow pulse, so it occupies a very large frequency spectrum range, and although it uses wireless communication, its data transmission rate can reach hundreds of megabits per second or more. Using the UWB technology can transmit signals over a very wide bandwidth, and the Federal Communications Commission (FCC) regulation for the UWB technology is to occupy a bandwidth of 500 MHz or more in the 3.1-10.6 GHz frequency band. UWB is essentially a carrierless spread spectrum technology that uses an impulse pulse with a very low duty cycle as an information carrier, which is directly modulated by an impulse pulse with very steep rising and falling times. A typical UWB directly emits an impulse pulse train, which no longer has the concept of traditional intermediate frequency and radio frequency. At this time, the transmitted signal can be regarded as a baseband signal (according to the conventional radio), and also as a radio frequency signal (from the frequency spectrum component of the transmitted signal). The impulse pulse usually uses a single-cycle Gaussian pulse, and one information bit can be mapped to hundreds of such pulses. The width of the single-cycle pulse is in the nanosecond level, and has a very wide frequency spectrum. UWB develops a new wireless channel with gigahertz capacity and the highest spatial capacity. The CDMA-based UWB pulse wireless transceiver generates a pulse sequence with a certain repetition period at the sending end clock generator. The information to be transmitted by the user and the pseudo-random code representing the user address are modulated in a certain way or combined to modulate the above-mentioned periodic pulse sequence. The modulated pulse sequence drives the pulse generating circuit to form a pulse sequence with a certain pulse shape and regularity, and then amplifies it to the required power and couples it to the UWB antenna for transmission. At the receiving end, the signal received by the UWB antenna is amplified by the low-noise amplifier and sent to one input of the correlator. The other input of the correlator adds a locally generated and synchronized pseudo-random code modulated pulse sequence with the sending end. The received signal and the locally synchronized pseudo-random code modulated pulse sequence are multiplied, integrated, and sampled and held in the correlator to produce a signal that separates the user address information, which only contains the user transmission information and other interference. Then, the signal is demodulated. The positioning device uses these two technologies to embed the Bluetooth + uwb module in the working station and the cable monitoring device. The uwb end of the monitoring device is usually in a dormant state. When the Bluetooth of the station and the monitoring device establishes a connection, the real-time distance finding function is opened by operation, the uwb is opened for distance finding, and the station end displays the distance and simple directionality of the corresponding monitoring device in real time.

[0057] From the above description, it can be seen that the above-mentioned embodiments of the present application achieve the following technical effects:

[0058] 1) The resonant temperature sensor of the present application, by the first metal sheet, the second metal sheet and the dielectric plate together constitute a capacitor, the capacitor and the induction coil together constitute an LC circuit, using the corresponding relationship between the characteristic frequency of the LC resonant circuit and the temperature, the internal conductor temperature of the cable joint can be directly read, and the material of the dielectric plate is ethylene-vinyl acetate copolymer added with PZT piezoelectric ceramic powder and nano-sized metal particles, the dielectric constant and its temperature coefficient of the material itself are large enough to generate additional capacitance on the basis of dielectric, and the flexible material can be directly embedded in the internal part of the cable joint and directly contact with the conductor, solving the problem of not being able to directly and accurately measure the temperature of the cable joint in a small and closed space.

[0059] 2) The cable joint temperature monitoring system of the present application generates electromagnetic signals through the signal transceiver, amplifies through the amplifier, cooperates with the multi-way relay and other capacitors and resistors, and sends the received signals into the controller after simple amplification processing; the control circuit transmits the resonant signal to the wireless passive flexible temperature sensor through the external reading coil, directly reads the internal conductor temperature of the cable joint by using the corresponding relationship between the characteristic frequency of the electromagnetic resonant circuit and the temperature; select SIM800C8 module with SIM card, directly transmit data to cloud server, then directly transmit to interactive host computer software through cloud, real-time monitor the internal conductor temperature of the cable joint; supplemented by positioning module, realize the accurate positioning of the cable joint position, facilitate the subsequent maintenance work. The above only for the preferred embodiment of the present application, and not for limiting the present application, for those skilled in the art, the present application can have various changes and variations. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A resonant temperature sensor, characterized by The resonant temperature sensor comprises a medium plate, a first metal sheet, a second metal sheet and an induction coil, the first metal sheet is attached to the upper surface of the medium plate, the second metal sheet is attached to the lower surface of the medium plate, and the first metal sheet and the second metal sheet are oppositely arranged, one end of the induction coil is connected with the first metal sheet. The material for preparing the medium plate is ethylene-vinyl acetate copolymer added with PZT piezoelectric ceramic powder and nano metal particles, and the resonant temperature sensor is used for monitoring the temperature inside the cable joint. The first metal sheet, the second metal sheet and the medium plate jointly constitute a capacitor. The resonant temperature sensor further comprises a protective layer, which covers the upper layer of the first metal sheet and the induction coil, and when the resonant temperature sensor is in a sheet shape, the protective layer also covers the surface of the second metal sheet away from the medium plate. The resonant temperature sensor is arranged outside the conductor connection pipe of the cable joint.

2. The resonant temperature sensor of claim 1, wherein, The shape of the induction coil is planar spiral, the first metal sheet is located at the center of the induction coil, and the second metal sheet is close to the outer surface of the conductor connection pipe.

3. The resonant temperature sensor of claim 2, wherein, The resonant temperature sensor is clamped between the inner insulation layer of the cable joint and the conductor connection pipe.

4. The resonant temperature sensor of claim 2, wherein, The resonant temperature sensor according to any one of claims 1 to 4 is installed inside the cable joint.

5. A cable joint temperature monitoring system characterised in that, A signal transceiver is installed in the surrounding area of the resonant temperature sensor, and is used for emitting an electromagnetic signal and receiving a resonance signal, wherein the induction coil generates electromagnetic induction under the excitation of the electromagnetic signal, so that the resonant temperature sensor generates the resonance signal. A processor is electrically connected with the signal transceiver, and is used for determining the temperature inside the cable joint according to the resonance signal. The processor comprises: A filtering unit is electrically connected with the signal transceiver, and is used for filtering the resonance signal to obtain a filtered resonance signal.

6. The cable joint temperature monitoring system of claim 5, wherein, A signal amplification unit is electrically connected with the filtering unit, and is used for amplifying the filtered resonance signal to obtain an amplified resonance signal. A signal processing unit is electrically connected with the signal amplification unit, and is used for determining the temperature inside the cable joint according to the resonance signal. The signal processing unit comprises: A signal demodulation module is used for demodulating the frequency of the amplified resonance signal.

7. The cable joint temperature monitoring system of claim 6, wherein, A signal processing module is electrically connected with the signal demodulation module, and is used for determining the temperature inside the cable joint according to the frequency of the amplified resonance signal. The processor further comprises: An analog-to-digital conversion unit is electrically connected with the signal amplification unit and the signal processing unit respectively, and is used for converting the amplified resonance signal into a digital signal.

8. The cable joint temperature monitoring system of claim 6, wherein, The cable joint temperature monitoring system further comprises: A cloud server in communication with the processor.

9. The cable joint temperature monitoring system of any one of claims 5 to 8, wherein, ​ ​

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