CN216899352U - Cable conductor temperature measuring device - Google Patents

Abstract

A cable conductor temperature measuring device is composed of a temperature sensor, a reading antenna, a control circuit, cloud platform monitoring software and a positioning module. The temperature sensor is attached to the cable conductor in a sensing mode of a resonant circuit. And a signal transceiver module in the control circuit sends a sweep frequency signal to the reading antenna, so that the reading antenna and the resonant circuit generate inductive coupling, the signal transceiver module receives a characteristic value fed back by the resonant circuit, and the temperature of the cable conductor is obtained through the corresponding relation between the characteristic value and the temperature. The temperature information is transmitted to the cloud platform monitoring software through the wireless transmission module, and real-time display of the temperature is achieved. The temperature and humidity reading module is placed in the control circuit, the surrounding environment state of the control circuit is monitored, and the damage of the control circuit caused by abnormal temperature or humidity is pre-warned. Through the positioning module, the abnormal temperature position of the cable is positioned, and the maintenance efficiency is improved.

Description

A cable conductor temperature measuring device

technical field

The utility model relates to the field of temperature measurement, in particular to a cable conductor temperature measurement device.

Background technique

With the improvement of the degree of modern industrialization and the rapid development of the national power Internet of Things, the voltage level of electrical equipment is constantly improving and the working current is also increasing, and people's demand for electricity is also getting higher and higher, resulting in electrical equipment heating damage. The phenomenon is becoming more and more serious, in which temperature is the most obvious indicator to detect whether an electrical device is working properly. Therefore, it can be judged whether the equipment is in a healthy state by detecting the temperature of the key parts of the electrical equipment. When the temperature is abnormal, it can be repaired in time to avoid larger failures. Therefore, it is necessary to conduct real-time detection of the temperature of key parts of electrical equipment.

For high-voltage cables, the cable conductors are the critical heating and fault location. Therefore, the temperature monitoring of the cable conductor requires that the sensor can directly contact the inner core conductor, so as to monitor the temperature of the conductor with higher precision. Considering the extremely small space inside the cable, the design of the sensor size has great requirements. At the same time, it is a strong electromagnetic field environment inside the cable, so the designed sensor should not be affected by the internal electric field distribution. The service life of the cable is generally 30 years, so the service life of the built-in sensor should not be less than 30 years. Based on the above problems, the utility model discloses a temperature measuring device for a cable conductor.

The temperature measurement system includes a temperature sensor, a reading antenna, a control circuit, a cloud platform monitoring software, and a positioning module. The signal transceiver module in the control circuit transmits a frequency sweep signal to the resonant sensor through the reading antenna, and uses the corresponding relationship between the characteristic value of the loop and the temperature to directly read the temperature of the cable conductor to realize real-time monitoring of the temperature. At the same time, the temperature and humidity reading module of the control circuit transmits the temperature and humidity information of the control circuit to the monitoring software of the cloud platform, so as to realize the real-time display of the performance status of the control circuit and warn the damage of the control circuit. Through the positioning module, the positioning of the abnormal temperature of the cable is realized, which provides convenience for subsequent maintenance.

Utility model content

Based on the above content, the present utility model provides a cable conductor temperature measurement device, including a temperature sensor, a reading antenna, a control circuit, a cloud platform monitoring software and a positioning module. The temperature sensor is attached to the cable conductor and is used for measuring The temperature of the cable conductor, the reading antenna and the temperature sensor are located in the same section and used to obtain the measured value of the temperature sensor, the control circuit is located outside the cable, is wired to the reading antenna, and transmits a frequency sweep signal to the temperature sensor.

The temperature sensor is composed of a temperature-sensitive substrate, a resonant circuit, and a protective layer. The temperature sensor is composed of making a resonant circuit on a temperature-sensitive substrate and attaching a protective layer to the surface of the circuit, and the temperature sensor is close to the cable conductor. The signal transceiver module makes the read antenna and the resonant circuit inductively couple by sending a frequency sweep signal, and receives the characteristic value signal fed back by the resonant circuit, and the control circuit is based on the characteristic value received by the signal transceiver module. temperature of the cable conductor.

The temperature sensitive substrate is polyethylene terephthalate.

In order to improve the measurement accuracy, preferably, a Q value is selected for the eigenvalue.

The resonant circuit in the temperature sensor adopts upper and lower plate capacitors and planar spiral inductors. In order to make the largest possible inductance value on the substrate, the multi-layer spiral inductance method is adopted. Two layers of inductors are made on top of the insulating protective layer of the outer coating of the capacitor, and the two layers of inductors rotate in the same direction. A protective layer is coated on the outside of the resonant circuit, and the inductor and the capacitor are connected in series in the form of through holes. This not only achieves a larger inductance value, but also has more protective layers to protect the circuit, while making the size of the sensor smaller. Finally, the lower plate of the capacitor is attached to the cable conductor, and the inductance is in multiple protective layers, which can prevent the breakage caused by directly attaching to the cable conductor for a long time, damage the sensor, and improve the service life of the sensor.

In order to improve the measurement sensitivity, preferably, the resonant circuit in the temperature sensor adopts an LC resonant circuit.

The reading antenna is composed of a multi-turn coil, and the reading antenna and the signal transceiving module are connected by wires.

The control circuit includes a signal transceiver module, a temperature and humidity reading module, a microcontroller and a wireless transmission module.

The signal transceiver module adopts AD9833 chip. The signal transceiver module is controlled by a microcontroller, transmits a frequency sweep signal to the reading antenna, and receives the feedback signal.

The temperature and humidity reading module adopts an HDC1080 temperature and humidity sensor, which is a digital humidity sensor with an integrated temperature sensor, which is used to detect the temperature and humidity of the control circuit and warn of damage to the control circuit.

The wireless transmission module adopts SIM800C module. The SIM800C module is a GSM/GPRS module. The data communication between the temperature measurement device and the cloud platform monitoring software is realized through the SIM800C module and the SIM card, and the data is first transmitted to the cloud server, and then directly transmitted to the cloud through the cloud. Platform monitoring software.

The AD9833 chip of the signal transceiver module does not need external components, and the output frequency and phase can be programmed by software, which is easy to adjust and control, and cooperates with a low-power microcontroller, which has the advantages of small size and low power consumption. The HDC1080 temperature and humidity sensor can monitor temperature and humidity signals at the same time, has the advantages of low cost and low power consumption, can be well combined with the microcontroller, and transmits information with the microcontroller through the I ² C bus. The wireless transmission module SIM800C has a compact appearance and stable performance, and is suitable for use in the surrounding environment of cables, and transmits data more accurately.

The microcontroller uses NXP Kinetis KEA series S9KEAZ64AMLH chip, up to 16-channel 12-bit SARADC, which is a common structure for medium to high-resolution applications, with low power consumption and small size.

The cloud platform monitoring software is used to display the temperature of the cable conductor and the temperature and humidity of the control circuit.

The model of the cloud platform monitoring software is built based on PYQT, and its functions are implemented by python programs.

The positioning module has a built-in Bluetooth module and an ultra-wideband wireless communication module in the work station and the control circuit board. The positioning module adopts the DWM1000 module, the clock in the DWM1000 module is 63.9GHz, as the frequency source of the counter, that is, a count timestamp corresponds to 15.65ps, which has extremely high ranging accuracy, and its positioning accuracy can reach centimeter level. The DWM1000 module communicates with the microcontroller through the SPI interface. When the Bluetooth connection between the work station and the control circuit board is established, the real-time ranging and searching function is turned on, and the UWB enables ranging, and the work station displays the distance of the corresponding cable and simple directional guidance in real time. Compared with GPS, UWB has strong penetrating ability and strong anti-jamming energy, while GPS positioning system can only work within the visible range of GPS positioning satellites.

To sum up, in the present invention, the signal transceiver module sends a frequency sweep signal to the reading antenna, the reading antenna is coupled with the resonant circuit, the signal transceiver module receives the signal with the characteristic value returned from the resonant circuit, and then the The signal is sent to the microcontroller, and the temperature of the cable conductor is obtained through the relationship between the characteristic value and the temperature. The data communication between the temperature measurement device and the cloud platform monitoring software is realized by the wireless transmission module. The temperature of the cable conductor is obtained in real time in the cloud platform monitoring software, which can realize early warning of faults. At the same time, the temperature and humidity sensor can be used in real time on the cloud platform monitoring software. The state of the surrounding environment of the control circuit is observed, and the positioning module can locate the abnormal temperature of the cable, which improves the maintenance efficiency.

The above description is a technical overview of the solution, and the preferred embodiments are exemplified below, and the detailed description is as follows in conjunction with the accompanying drawings.

Description of drawings

Figure 1 shows a block diagram of a cable conductor temperature measuring device provided by the utility model

Figure 2 shows a schematic diagram of a cable conductor temperature measuring device installed inside the cable

Figure 3 shows a cross-sectional view of the temperature sensor in Figure 2

Figure 4 shows a schematic diagram of the structure of the inductor coil and capacitor in Figure 2

The block diagram of the control circuit system shown in Figure 5

Figure 6 shows the block diagram of the positioning module system

Detailed ways

In order to further illustrate the technical means adopted by the present utility model to achieve the predetermined utility model purpose, the following detailed description is as follows in conjunction with the accompanying drawings and preferred embodiments:

Figure 1 shows a block diagram of a cable conductor temperature measuring device provided by the utility model. The temperature measurement system includes a temperature sensor, a reading antenna, a control circuit and a cloud platform monitoring software, wherein the control circuit includes a signal transceiver module, a temperature and humidity reading module, a microcontroller and a wireless transmission module. The signal transceiver module adopts AD9833 chip, the AD9833 chip is controlled by the microcontroller to transmit frequency sweep signal, the temperature and humidity reading module adopts HDC1080 temperature and humidity sensor, the wireless transmission module in the control circuit adopts SIM800C module, and the microcontroller adopts NXP S9KEAZ64AMLH chip. By reading the coupling between the antenna and the temperature sensor, the signal transceiver module AD9833 receives the signal with Q value information returned from the temperature sensor, and then transmits the signal to the microcontroller S9KEAZ64AMLH, and obtains the cable conductor through the corresponding relationship between the Q value and the temperature. temperature. The temperature and humidity sensor HDC1080 transmits the obtained signal to the microcontroller S9KEAZ64AMLH by sensing the surrounding environment, and the obtained temperature and humidity information will be transmitted to the cloud platform monitoring software through the wireless transmission module SIM800C for real-time monitoring by personnel.

Figure 2 shows a schematic diagram of a cable conductor temperature measuring device installed inside the cable. The cable conductor 11, the temperature sensor 12 is attached to the cable conductor 11, between the inner insulating layer 13 and the outer insulating layer 15, and the reading antenna 16 is placed above the shielding layer 14, between the shielding layer 14 and the outer insulating layer 15 , are encased in the cable casing 17 .

The reading antenna 17 generates electromagnetic coupling with the temperature sensor 12 through the frequency sweep signal transmitted by the signal transceiver module AD9833, thereby performing signal transmission. There is only one inner insulating layer 13 between the reading antenna 16 and the temperature sensor 12, which makes the signal transmission process more stable.

The control circuit provided by the present invention is located outside the cable casing 17 and is connected to the reading antenna 16 through wires.

FIG. 3 is a cross-sectional view of the temperature sensor in FIG. 2 . The temperature sensor 12 is composed of a capacitor 121 , a temperature-sensitive material 126 , a first-layer inductor 123 , a second-layer inductor 122 , a capacitor protection layer 127 , an insulating protection layer 125 and a protection layer 124 . The inductors 122 and 123 are placed directly above the capacitor 121. A temperature-sensitive material 126 is placed between the upper and lower plates of the capacitor 121. A protective layer 127 is applied outside the capacitor 121. The first layer of inductor 123 is made on the protective layer 127. A layer of insulating protection layer 125 is coated on the first layer of inductor 123, a second layer of inductor 122 is made on top of the insulating protection layer 125, and finally a layer of protection layer 124 is coated on the outside of the resonant circuit to protect the circuit to prevent the resonant circuit from being damaged by other influences.

The temperature-sensitive substrate provided by the utility model is polyethylene terephthalate.

The temperature sensor 12 provided by the present invention adopts a sheet-like attachment type, which can be directly attached to the cable conductor 11, which is convenient for heat conduction and more accurate in temperature detection.

The magnetic flux of the temperature-sensitive material 126 in the middle layer of the capacitor 121 is significantly changed by temperature, resulting in a significant change in the inductance value and finally a change in the Q value. The temperature can be obtained by observing the corresponding relationship between the Q value and the temperature.

FIG. 4 is a schematic diagram showing the structure of the inductor and capacitor in FIG. 2 . The capacitor 121 is of the parallel plate type, and the inductors 122 and 123 are of the plane spiral type.

Figure 5 shows the block diagram of the control circuit system. The control circuit is outside the cable housing 17, the signal transceiver module AD9833 is controlled by the microcontroller S9KEAZ64AMLH to transmit a frequency sweep signal to the reading antenna 16, the reading antenna is coupled with the temperature sensor 12, and the signal transceiver module AD9833 receives the feedback signal and transmits it to The microcontroller S9KEAZ64AMLH performs processing, and the temperature and humidity sensor HDC1080 senses the external environmental conditions of the control circuit, and also transmits the signals received from the outside to the microcontroller S9KEAZ64AMLH for processing. The signals received by the microcontroller S9KEAZ64AMLH will be transmitted to the cloud platform monitoring software through the SIM800C module for display.

Figure 6 shows the block diagram of the positioning module system. The positioning module has built-in Bluetooth and UWB modules in the work station and the control circuit board. The UWB side of the control circuit board is usually in a dormant state. When the Bluetooth connection between the work station and the control circuit board is established, the real-time ranging and searching function is turned on, and the UWB enables ranging, and the work station displays the distance of the cable and simple directional guidance in real time. When the cable fails, it can be positioned in time, saving time and improving maintenance efficiency.

To sum up, the cable conductor temperature measuring device in the present invention is controlled by the signal transceiver module AD9833 to transmit the sweep frequency signal to the reading antenna 16 under the control of the microcontroller S9KEAZ64AMLH, so that the reading antenna 16 is coupled with the temperature sensor 12, The signal transceiver module AD9833 receives and returns the signal with Q value information, and after a series of circuits amplifies the signal, it is transmitted to the microcontroller S9KEAZ64AMLH, and then wirelessly transmitted to the cloud platform monitoring software through the SIM800C module. The temperature and humidity sensor HDC1080 receives changes in the external environment, transmits the information to the microcontroller S9KEAZ64AMLH for processing, and finally transmits it to the cloud platform monitoring software. At the same time, there are built-in Bluetooth and UWB modules in the work table and the control circuit board. When the two ends are connected by Bluetooth, the work table can accurately locate the cable. The sensor in the utility model adopts the resonant sensor, and the size is small and can be directly attached to the cable conductor, the temperature of the cable conductor is directly monitored, and the measured temperature is more accurate.

Claims (8)

1. a cable conductor temperature measuring device, it is characterized in that: comprise temperature sensor, reading antenna, control circuit, cloud platform monitoring software and positioning module, described temperature sensor is attached on the cable conductor, and is used to measure the temperature of the cable conductor. temperature, the reading antenna and the temperature sensor are located in the same section, and are used to obtain the measurement value of the temperature sensor. 2. A cable conductor temperature measuring device according to claim 1, wherein the temperature sensor is composed of a temperature-sensitive substrate, a resonant circuit, and a protective layer. 3 . The temperature measuring device for cable conductors according to claim 2 , wherein the temperature-sensitive substrate is polyethylene terephthalate. 4 . 4 . The temperature measuring device for cable conductors according to claim 1 , wherein the temperature sensor and the reading antenna perform data transmission through inductive coupling. 5 . 5 . The temperature measuring device for cable conductors according to claim 1 , wherein the control circuit comprises a signal transceiver module, a temperature and humidity reading module, a microcontroller and a wireless transmission module. 6 . 6. A cable conductor temperature measuring device as claimed in claim 5, characterized in that: the signal transceiver module adopts AD9833 chip, and the AD9833 chip is controlled by the microcontroller to transmit a frequency sweep signal, and the temperature and humidity reading module HDC1080 temperature and humidity sensor is adopted, the wireless transmission module in the control circuit adopts SIM800C module, and the microcontroller adopts NXP S9KEAZ64AMLH chip. 7. A cable conductor temperature measurement device according to claim 1, wherein the cloud platform monitoring software is used to display the temperature of the cable conductor and the temperature and humidity of the control circuit. 8 . The temperature measuring device for cable conductors according to claim 1 , wherein the positioning module is composed of an ultra-wideband wireless communication device and a Bluetooth device, and the positioning module adopts a DWM1000 module. 9 .

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