Temperature monitoring device for electrical penetrations in nuclear power plants

Abstract

This invention discloses a temperature monitoring device for electrical penetrations in nuclear power plants, comprising an electromagnetic induction energy harvesting module, an energy management module, a backup battery, a temperature monitoring probe, and a data processing module. The electromagnetic induction energy harvesting module, backup battery, temperature monitoring probe, and data processing module are all electrically connected to the energy management module. The temperature monitoring probe is used to detect the temperature of the electrical penetration. The temperature monitoring probe is electrically connected to the data processing module, which converts the data collected by the temperature monitoring probe and then outputs or stores it. The electromagnetic induction energy harvesting module is installed on the connecting cable of the electrical penetration, and it generates an induced current by sensing changes in the magnetic field around the connecting cable, which is then output to the energy management module. The energy management module rectifies and regulates the voltage of the induced current before outputting it to the temperature monitoring probe and the data processing module. The temperature monitoring device provided by this invention can economically and effectively perform long-term temperature detection of electrical penetrations.

Description

Technical Field

[0001] This invention relates to the field of environmental assessment and condition evaluation of electrical equipment in nuclear power plants, and in particular to a temperature monitoring device for electrical penetrations in nuclear power plants. Background Technology

[0002] An electrical penetration device (EPD) is a specialized electrical facility installed on the containment structure of a nuclear power plant for cables to pass through it. As part of the containment structure, it forms the reactor safety barrier, ensuring the continuity and reliability of electrical signals for equipment in the reactor building and other buildings under normal operating conditions and design-based accident conditions. It also maintains the integrity and sealing of pressure boundaries, preventing the leakage of radioactive materials.

[0003] Electrical penetrations operate under rated current for extended periods, inevitably causing conductor temperature rise. Due to the stringent airtightness requirements of these penetrations, the heat generated by the conductor accumulates inside the penetration casing. This sustained high-temperature environment causes the organic insulation and sealing materials to gradually crack, leading to a decline in insulation and sealing performance, thus affecting the electrical and mechanical functions of the penetration. Traditional contact temperature measurement methods pose a risk of damaging the physical structure of the object being measured, impacting normal equipment operation. Therefore, it is essential to conduct long-term temperature monitoring of electrical penetrations and develop corresponding temperature monitoring devices to ensure that they meet safety requirements throughout their entire service life.

[0004] The above background information is provided only to assist in understanding the inventive concept and technical solution of this invention. It does not necessarily belong to the prior art of this patent application, nor does it necessarily provide technical teaching. In the absence of clear evidence that the above information was disclosed before the filing date of this patent application, the above background information should not be used to evaluate the novelty and inventiveness of this application. Summary of the Invention

[0005] To overcome the shortcomings of existing technologies, this invention provides a temperature monitoring device for electrical penetrations in nuclear power plants, the specific technical solution of which is as follows:

[0006] A temperature monitoring device for electrical penetrations in nuclear power plants is provided, comprising an electromagnetic induction energy harvesting module, an energy management module, a backup battery, a temperature monitoring probe, and a data processing module; the electromagnetic induction energy harvesting module, the backup battery, the temperature monitoring probe, and the data processing module are respectively electrically connected to the energy management module;

[0007] The temperature monitoring probe is used to detect the temperature of the electrical penetration component; the temperature monitoring probe is electrically connected to the data processing module, which converts the data collected by the temperature monitoring probe and outputs or stores it; the electromagnetic induction energy harvesting module is installed on the connecting cable of the electrical penetration component, which generates an induced current by sensing the change in the magnetic field around the connecting cable and outputs it to the energy management module, which rectifies and regulates the voltage of the induced current and outputs it to the temperature monitoring probe and the data processing module.

[0008] When the induced current output by the electromagnetic induction energy harvesting module is less than a preset value, the energy management module draws power from the backup battery to supplement the insufficient power supply of the electromagnetic induction energy harvesting module; when the induced current output by the electromagnetic induction energy harvesting module is greater than the preset value, the energy management module charges the backup battery to consume part of the power supply of the electromagnetic induction energy harvesting module.

[0009] Furthermore, the electrical penetration device is installed on the containment vessel of the nuclear power plant. The electrical penetration device includes a cylinder and a feeder line. The cylinder passes through the containment vessel, and the feeder line passes through the cylinder and is connected to a cable in a junction box outside the containment vessel via a port assembly. The temperature monitoring probe uses non-contact infrared thermometry technology and is located at the end of the cylinder outside the containment vessel of the electrical penetration device. The temperature collected by the temperature monitoring probe is used as the temperature of the outer surface of the cylinder end. Combined with a preset offline temperature rise simulation test model of the electrical penetration device, the actual operating temperature inside the cylinder is predicted. Combined with the temperature of the surrounding environment of the electrical penetration device, the temperature rise of the outer surface of the cylinder end and the temperature rise of the feeder line end are obtained.

[0010] Furthermore, the temperature monitoring device also includes a microcontroller, which receives monitoring data from the temperature monitoring probe through the data processing module;

[0011] If the temperature rise on the outer surface of the cylinder end is detected to be greater than a first preset value, or the temperature rise at the end of the feeder line is detected to be greater than a second preset value, the microcontroller outputs an alarm signal to the remote control room, wherein the first preset value is less than the second preset value.

[0012] Furthermore, if the predicted actual operating temperature inside the cylinder is greater than a third preset value, the microcontroller outputs an alarm signal to the remote control room.

[0013] Furthermore, the microcontroller transmits the monitored temperature data to a remote control room for integrated display via 4G / 5G communication protocols.

[0014] Furthermore, when the induced current output by the electromagnetic induction energy harvesting module is less than a preset value and the power of the backup battery is less than the safe power, the microcontroller reduces the sampling frequency of the temperature monitoring probe; when the induced current output by the electromagnetic induction energy harvesting module is greater than the preset value and the backup battery is fully charged, the microcontroller increases the sampling frequency of the temperature monitoring probe.

[0015] Furthermore, when the induced current output by the electromagnetic induction energy harvesting module is greater than a preset value and the backup battery is fully charged, the energy management module draws power from the backup battery and automatically disconnects from the electromagnetic induction energy harvesting module. When the power of the backup battery drops to a preset level, it automatically reconnects to the electromagnetic induction energy harvesting module.

[0016] Furthermore, when the microcontroller outputs an alarm signal, the microcontroller increases the sampling frequency of the temperature monitoring probe.

[0017] Furthermore, there are multiple feedthrough lines, and these multiple dispersed feedthrough lines are integrated into one unit through a port assembly to connect to the connecting cable, which is located outside the containment enclosure.

[0018] Furthermore, the microcontroller is electrically connected to the energy management module, and the microcontroller can regulate the output voltage of the energy management module.

[0019] Compared with the prior art, the present invention has the following advantages: it can economically and effectively conduct long-term temperature detection of electrical penetrations without affecting their normal operation. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the temperature monitoring device provided in an embodiment of the present invention;

[0021] Figure 2 This is a schematic diagram of the electrical penetration component installation structure in the temperature monitoring device provided in this embodiment of the invention.

[0022] The attached diagram is labeled as follows: 1-Containment, 2-Cylinder, 3-Feeder. Detailed Implementation

[0023] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0024] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion.

[0025] In one embodiment of the present invention, a temperature monitoring device for electrical penetrations in nuclear power plants is provided, see [link to relevant documentation]. Figure 1 It includes an electromagnetic induction energy harvesting module, an energy management module, a backup battery, a temperature monitoring probe, and a data processing module; the electromagnetic induction energy harvesting module, the backup battery, the temperature monitoring probe, and the data processing module are all electrically connected to the energy management module.

[0026] The temperature monitoring probe is used to detect the temperature of the electrical penetration component. The temperature monitoring probe is electrically connected to a data processing module, which converts the data collected by the temperature monitoring probe and then outputs or stores it. Specifically, the temperature monitoring probe is an infrared temperature probe. The task of the infrared temperature probe is to convert thermal radiation energy into an electrical signal. Due to the complexity of the temperature measurement environment, such as high temperature, water vapor, smoke, and mechanical vibration, a temperature measuring instrument with high anti-interference capability is required to ensure that the device can operate stably for a long time under complex conditions in order to obtain a target electrical signal with a high signal-to-noise ratio. The infrared temperature probe converts the infrared radiation emitted by the conductor into an analog electrical signal through high-frequency sampling, and then converts it from digital to analog for subsequent storage and processing. Furthermore, since the intensity of the infrared signal is affected by distance and environmental conditions, the signal may contain noise and interference. Therefore, digital-to-analog conversion technology is also involved in signal filtering and amplification to ensure reliable access to the temperature measurement data.

[0027] The electromagnetic induction energy harvesting module is installed on the connecting cable of the electrical penetration component. It generates an induced current by sensing the change in the magnetic field around the connecting cable and outputs it to the energy management module. The energy management module rectifies and regulates the voltage of the induced current and outputs it to the temperature monitoring probe and the data processing module.

[0028] When the induced current output by the electromagnetic induction energy harvesting module is less than a preset value, the energy management module draws power from the backup battery to supplement the insufficient power supply of the electromagnetic induction energy harvesting module; when the induced current output by the electromagnetic induction energy harvesting module is greater than the preset value, the energy management module charges the backup battery to consume part of the power supplied by the electromagnetic induction energy harvesting module. Specifically, the electromagnetic induction energy harvesting module harvests energy in the form of an electromagnetic induction coil, which is installed on the outer sheath of the electrical penetration cable and harvests energy by inducing the surrounding magnetic field. Because the current variation range in the circuit is large, the current transformer may fail to harvest energy, therefore a backup battery is introduced to power the circuit. When the operating current of the connecting cable is too low, the electromagnetic induction energy harvesting module, together with the backup battery, powers the entire temperature monitoring device. When there is no current in the connecting cable, the electromagnetic induction coil generates no induced current, and the backup battery powers the temperature monitoring device alone. When the operating current of the connecting cable is too high, the energy harvesting circuit powers the temperature monitoring device and simultaneously charges the backup battery with the remaining energy. When the operating circuit of the connecting cable is constantly under high current, the energy management module activates the frequency converter control to regulate the output voltage of the system, ensuring that the output current remains stable within the limits of the subsequent load.

[0029] Since the induced current is sinusoidal AC, in order to meet the load's requirement for DC voltage flatness, it needs to be rectified and filtered to convert AC to DC for use by the temperature monitoring probe. Since the voltage of the operating circuit may vary widely, a voltage regulator can be connected to deal with voltage fluctuations and distortions during decoupling and accurately output trigger pulses for load operation. This allows the energy management module to use a voltage regulator for rectification and transformation regulation.

[0030] In one embodiment of the present invention, see Figure 2 The electrical penetration device is installed on the containment vessel of the nuclear power plant. The electrical penetration device includes a cylinder 2, a feeder line 3, and a junction box. The cylinder 2 passes through the concrete wall of the containment vessel 1. The junction box is located on the outside of the containment vessel 1 and connected to the cylinder 2. The feeder line 3 passes through the cylinder 2 and is connected to a cable outside the containment vessel via a port assembly inside the junction box. Specifically, there are multiple feeder lines, which are integrated into one unit through the port assembly to connect to the connecting cable. The temperature monitoring probe uses non-contact infrared thermometry and is located inside the junction box. The temperature detected by the temperature monitoring probe is taken as the temperature of the outer surface of the cylinder end. Combined with a preset electrical penetration device temperature rise simulation test model, the predicted temperature inside the cylinder is obtained. Combined with the temperature of the surrounding environment of the electrical penetration device, the temperature rise of the outer surface of the cylinder end and the predicted temperature rise inside the cylinder are obtained.

[0031] The temperature monitoring device in this embodiment adopts non-contact infrared thermometry technology. It uses the relationship between conductor temperature and infrared radiation intensity to monitor and store temperature data. Without affecting the normal operation of electrical penetrations, it has the characteristics of high temperature resolution and fast response speed, and does not interfere with the temperature distribution field of the measured object.

[0032] Non-contact infrared thermometry technology has advantages such as long-distance transmission, real-time monitoring, and high measurement accuracy, and can be widely applied to normal, abnormal, transient, and post-accident conditions of electrical penetrations. The principle of infrared thermometry is to use a temperature probe to receive infrared radiation from the target conductor, convert it into an analog electrical signal, and then the sampling chip in the data processing module performs digital-to-analog conversion and stores it as a digital signal. By establishing a proportional model between radiation energy and conductor temperature, digital calculations for temperature compensation and correction are performed to obtain the surface temperature of the monitored object.

[0033] Considering the specific operating conditions of the electrical penetration component during long-term operation, this embodiment decides to use electromagnetic induction to power the temperature monitoring device. When the normal power supply line is cut off, the backup battery can continue to supply power to the temperature monitoring device, ensuring real-time monitoring and collection of temperature sampling signals.

[0034] In one embodiment of the present invention, the temperature monitoring device further includes a microcontroller, which is electrically connected to the energy management module, the data processing module, and the temperature monitoring probe, respectively. The microcontroller can regulate the output voltage of the energy management module and the sampling frequency of the temperature monitoring probe, enabling the energy management module and the temperature monitoring probe to operate in coordination. The microcontroller transmits the monitored temperature data to a remote control room for integrated display via 4G / 5G communication protocols, either wirelessly or via wired connection.

[0035] The microcontroller receives monitoring data from the temperature monitoring probe via the data processing module. If the temperature rise on the outer surface of the cylinder end is detected to be greater than a first preset value, or the temperature rise at the end of the feeder line is detected to be greater than a second preset value, the microcontroller outputs an alarm signal to the remote control room. The first preset value is less than the second preset value. Temperature rise refers to the difference between the actual temperature of the temperature measuring component and the ambient temperature. For example, the first preset value is 15°C and the second preset value is 30°C. If the predicted actual operating temperature inside the cylinder is greater than a third preset value, the microcontroller outputs an alarm signal to the remote control room. The third preset value is 70°C. When the microcontroller outputs an alarm signal, it increases the sampling frequency of the temperature monitoring probe.

[0036] In one embodiment of the present invention, when the induced current output by the electromagnetic induction energy harvesting module is less than a preset value and the power of the backup battery is less than the safe power, the microcontroller reduces the sampling frequency of the temperature monitoring probe to save power; when the induced current output by the electromagnetic induction energy harvesting module is greater than the preset value and the backup battery is fully charged, the microcontroller increases the sampling frequency of the temperature monitoring probe to consume excess power.

[0037] In one embodiment of the present invention, when the induced current output by the electromagnetic induction energy harvesting module is greater than a preset value and the backup battery is fully charged, the energy management module draws power from the backup battery and automatically disconnects from the electromagnetic induction energy harvesting module. When the power of the backup battery drops to a preset power level, it automatically reconnects to the electromagnetic induction energy harvesting module.

[0038] The temperature monitoring device for electrical penetrations in nuclear power plants provided by this invention uses infrared thermometry to monitor the end temperature of the electrical penetration cylinder. Combined with the temperature rise simulation test model of the electrical penetration, the temperature of the conductor inside the electrical penetration cylinder is obtained. By sampling temperature signals in real time and accurately, a temperature database of the electrical penetration under various operating conditions is established, providing data support for the aging management and in-service status monitoring of the electrical penetration.

[0039] The above description is merely a preferred embodiment of the present invention and does not limit its patent scope. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, whether directly or indirectly applied to other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A temperature monitoring device for electrical penetrations in nuclear power plants, characterized in that, It includes an electromagnetic induction energy harvesting module, an energy management module, a backup battery, a temperature monitoring probe, and a data processing module; the electromagnetic induction energy harvesting module, the backup battery, the temperature monitoring probe, and the data processing module are all electrically connected to the energy management module. The temperature monitoring probe is used to detect the temperature of the electrical penetration component; the temperature monitoring probe is electrically connected to the data processing module, which converts the data collected by the temperature monitoring probe and outputs or stores it; the electromagnetic induction energy harvesting module is installed on the connecting cable of the electrical penetration component, which generates an induced current by sensing the change in the magnetic field around the connecting cable and outputs it to the energy management module; the energy management module rectifies and regulates the voltage of the induced current and outputs it to the temperature monitoring probe and the data processing module. When the induced current output by the electromagnetic induction energy harvesting module is less than a preset value, the energy management module draws power from the backup battery to supplement the insufficient power supply of the electromagnetic induction energy harvesting module; when the induced current output by the electromagnetic induction energy harvesting module is greater than the preset value, the energy management module charges the backup battery to consume part of the power supply of the electromagnetic induction energy harvesting module.

2. The temperature monitoring device according to claim 1, characterized in that, The electrical penetration device is installed on the containment vessel of the nuclear power plant. The electrical penetration device includes a cylinder and a feeder line. The cylinder passes through the containment vessel, and the feeder line passes through the cylinder, connecting to a cable in a junction box outside the containment vessel via a port assembly. The temperature monitoring probe uses non-contact infrared thermometry and is positioned at the end of the cylinder outside the containment vessel. The temperature collected by the temperature monitoring probe is used as the temperature of the outer surface of the cylinder end. Combined with a preset offline temperature rise simulation test model for the electrical penetration device, the actual operating temperature inside the cylinder is predicted. Furthermore, by combining this with the ambient temperature around the electrical penetration device, the temperature rise of the outer surface of the cylinder end and the temperature rise of the feeder line end are obtained.

3. The temperature monitoring device according to claim 2, characterized in that, It also includes a microcontroller, which receives monitoring data from the temperature monitoring probe through the data processing module; If the temperature rise on the outer surface of the cylinder end is detected to be greater than a first preset value, or the temperature rise at the end of the feeder line is detected to be greater than a second preset value, the microcontroller outputs an alarm signal to the remote control room, wherein the first preset value is less than the second preset value.

4. The temperature monitoring device according to claim 3, characterized in that, If the predicted actual operating temperature inside the cylinder is greater than the third preset value, the microcontroller outputs an alarm signal to the remote control room.

5. The temperature monitoring device according to claim 3, characterized in that, The microcontroller transmits the monitored temperature data to a remote control room for integrated display via 4G / 5G communication protocols.

6. The temperature monitoring device according to claim 3, characterized in that, When the induced current output by the electromagnetic induction energy harvesting module is less than a preset value and the power of the backup battery is less than the safe power, the microcontroller reduces the sampling frequency of the temperature monitoring probe; when the induced current output by the electromagnetic induction energy harvesting module is greater than the preset value and the backup battery is fully charged, the microcontroller increases the sampling frequency of the temperature monitoring probe.

7. The temperature monitoring device according to claim 1, characterized in that, When the induced current output by the electromagnetic induction energy harvesting module is greater than a preset value and the backup battery is fully charged, the energy management module draws power from the backup battery and automatically disconnects from the electromagnetic induction energy harvesting module. When the power of the backup battery drops to a preset level, it automatically reconnects to the electromagnetic induction energy harvesting module.

8. The temperature monitoring device according to claim 3, characterized in that, When the microcontroller outputs an alarm signal, the microcontroller increases the sampling frequency of the temperature monitoring probe.

9. The temperature monitoring device according to claim 2, characterized in that, There are multiple feedthrough lines, which are integrated into one unit through a port assembly to connect to the connecting cable, which is located outside the containment enclosure.

10. The temperature monitoring device according to claim 3, characterized in that, The microcontroller is electrically connected to the energy management module, and the microcontroller can regulate the output voltage of the energy management module.

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