CN110853781B - Comprehensive monitoring system and method for spent fuel pool of nuclear power station - Google Patents
Comprehensive monitoring system and method for spent fuel pool of nuclear power station Download PDFInfo
- Publication number
- CN110853781B CN110853781B CN201911017337.2A CN201911017337A CN110853781B CN 110853781 B CN110853781 B CN 110853781B CN 201911017337 A CN201911017337 A CN 201911017337A CN 110853781 B CN110853781 B CN 110853781B
- Authority
- CN
- China
- Prior art keywords
- liquid level
- signal
- sensor
- temperature
- switching value
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
- G21C—NUCLEAR REACTORS
- G21C17/00—Monitoring; Testing ; Maintaining
- G21C17/02—Devices or arrangements for monitoring coolant or moderator
- G21C17/035—Moderator- or coolant-level detecting devices
-
- G—PHYSICS
- G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
- G21C—NUCLEAR REACTORS
- G21C17/00—Monitoring; Testing ; Maintaining
- G21C17/10—Structural combination of fuel element, control rod, reactor core, or moderator structure with sensitive instruments, e.g. for measuring radioactivity, strain
-
- G—PHYSICS
- G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
- G21C—NUCLEAR REACTORS
- G21C17/00—Monitoring; Testing ; Maintaining
- G21C17/10—Structural combination of fuel element, control rod, reactor core, or moderator structure with sensitive instruments, e.g. for measuring radioactivity, strain
- G21C17/112—Measuring temperature
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E30/00—Energy generation of nuclear origin
- Y02E30/30—Nuclear fission reactors
Abstract
The invention provides a comprehensive monitoring system and method for a spent fuel pool of a nuclear power station, which comprises a plurality of switching value liquid level signal acquisition assemblies, a plurality of temperature signals and a plurality of switching value liquid level signal acquisition assemblies, wherein the switching value liquid level signal acquisition assemblies are used for acquiring and transmitting a plurality of standard temperature signals of the pool; the analog quantity liquid level detector is used for detecting the liquid level of the spent fuel pool; and the processing and transmitting unit is used for receiving the temperature signal, the thermal diffusion type liquid level signal and the liquid level signal of the analog quantity liquid level detector, judging whether the received temperature signal is an effective water temperature signal according to the received thermal diffusion type liquid level signal, and displaying the liquid level height and the water temperature of the water pool. The invention adopts the thermal diffusion type and guided wave radar diversified measurement technology for the liquid level measurement of the spent fuel pool, realizes that the liquid level of the spent fuel pool can be exactly obtained under various working conditions, and ensures the safety of the spent fuel pool; meanwhile, the water temperature of different elevations can be measured simultaneously by the non-heating element of the thermal diffusion type liquid level measurement, whether hot spots exist at different elevations of the water pool can be accurately detected, and the reliability is high.
Description
Technical Field
The invention relates to the technical field of a spent fuel pool of a nuclear power station, in particular to a comprehensive monitoring system and method for the spent fuel pool of the nuclear power station.
Background
In a nuclear power plant, a spent fuel pool cooling and treatment system does not directly participate in the reactivity control of the core and spent fuel, but provides subcritical margin for fuel assemblies stored in the spent fuel pool, and the system must discharge decay heat of the fuel assemblies stored in the spent fuel pool and perform a radioactive containment function by ensuring a containment isolation function. Under the design benchmark accident, the complete loss of the spent fuel pool cooling system is not considered, the pool cannot be boiled, the evaporation loss is not obvious, only an SSE (safe shut-down earthquake) earthquake-resistant water replenishing source is needed, and the water source flow is within the envelope range of the over-design benchmark accident. Under the over-design benchmark accident, such as common mode accidents like strong shock, tsunami and the like, and the mechanical and electrical faults of the spent fuel pool cooling system, the spent fuel pool completely loses normal cooling, the decay heat of the spent fuel assembly causes the pool to be heated to boiling, if no effective water supplement is available, the water level of the spent fuel pool continuously drops until the spent fuel assembly is exposed, and finally the spent fuel assembly loses cooling to cause cladding failure, so that a large amount of radioactivity is released to the environment. In addition, in the event of accidental drainage of the spent fuel pool, the system must avoid direct exposure of the fuel assemblies stored in the fuel grids, which is also required during fuel lifting. Therefore, the accurate measurement of the temperature and the liquid level of the spent fuel pool is realized under various working conditions, so that the water level of the spent fuel pool is ensured to be above the shielding liquid level of the spent fuel and has no temperature hot spot, and the method has very important effect on ensuring the safety of the spent fuel pool.
Traditional nuclear power station spent fuel pool temperature measurement sets up alone with the level measurement, and wherein the level measurement mainly adopts one of following two kinds of modes: one method is to output a liquid level switch quantity and an analog quantity signal based on a thermal diffusion principle, but the analog quantity measuring method has poor precision and is greatly influenced by water temperature fluctuation; in addition, the guided wave radar is adopted to singly output an analog quantity signal, but an alarm signal of the guided wave radar needs to be converted from the analog quantity signal, so that the problem of large measurement error exists in the extreme environment of a spent fuel pool with a large amount of steam. The liquid level measurement adopts single guided wave radar measurement, and the common cause failure risk exists under the extreme environment condition; the temperature sensor can only measure the temperature of pool water at a single elevation, and cannot reflect local hot spots. The prior art is provided with a spent fuel pool state continuous monitoring system, which adopts a combination instrument of a continuous liquid level sensor based on a thermal diffusion principle, a liquid level switch and an RTD (thermal resistance temperature sensor), but the continuous liquid level sensor based on the thermal diffusion principle has poor measurement precision, and has larger measurement deviation particularly under the condition of larger water temperature difference between pool layers; the continuous liquid level sensor and the liquid level switch both adopt a thermal diffusion principle, have no diversified measurement means, and have a common cause failure risk under extreme environmental conditions. Therefore, in the prior art, the parameter measurement of the spent fuel pool has the technical problems of scattered acquisition, inconvenience in installation and replacement, single signal source in liquid level measurement and inaccurate measurement under certain working conditions.
Therefore, the prior art has the defects and needs to be improved.
Disclosure of Invention
The invention provides a comprehensive monitoring system and a method for a spent fuel pool of a nuclear power station, which can enable an operator to accurately know parameter conditions of the pool so as to take corresponding measures and ensure the safety of the spent fuel pool, aiming at the technical problems of scattered acquisition, inconvenient installation and replacement, single signal source of liquid level measurement and inaccurate measurement under certain working conditions of the parameter measurement of the spent fuel pool in the prior art.
The technical scheme provided by the invention for the technical problem is as follows:
a nuclear power station spent fuel pool integrated monitoring system includes: the temperature/switching value liquid level acquisition assemblies are respectively arranged from top to bottom along different elevations of the spent fuel pool and are used for acquiring and transmitting temperature signals of a plurality of liquid levels of the pool and thermal diffusion type switching value liquid level signals in real time; the analog quantity liquid level detector is arranged in parallel with the temperature/switching quantity liquid level acquisition assembly and is inserted into the pool body of the spent fuel pool to continuously detect the liquid level of the spent fuel pool; and the processing transmitting unit is respectively connected with the temperature/switching value liquid level acquisition assembly and the analog quantity liquid level detector, is used for receiving the temperature signal, the thermal diffusion switching value liquid level signal and the liquid level signal of the analog quantity liquid level detector, judges whether the received temperature signal is an effective water temperature signal according to the received thermal diffusion switching value liquid level signal, and displays the height of the liquid level of the water pool and the water temperature.
The temperature/switching value liquid level acquisition assembly comprises a plurality of thermal resistance sensor assemblies which are respectively arranged at different elevation positions of the spent fuel pool, each thermal resistance sensor assembly comprises a first sensor and a second sensor which are arranged in pairs, the first sensor at the same elevation is used for acquiring a water temperature signal at the same elevation, the second sensor at the same elevation, which is correspondingly arranged with the first sensor, is used for acquiring a water temperature signal after high heat diffusion of the corresponding pool after heating, and the switching value liquid level signal at the elevation is obtained by calculation according to the water temperature signals acquired by the first sensor and the second sensor; the analog quantity liquid level detector comprises a guided wave radar liquid level meter measuring and sensing unit, is arranged at the top of the water pool and is used for sending and receiving guided wave radar analog quantity liquid level signals under the control of the processing and transmitting unit; the processing and transmitting unit is further used for receiving the temperature signals and the thermal diffusion type switching value liquid level signals, judging whether the received temperature signals are effective water temperature signals or not according to the received thermal diffusion type switching value liquid level signals, and calculating the liquid level height of the spent fuel pool according to the time difference of sending and receiving the guided wave radar analog quantity liquid level signals.
The processing and transmitting unit comprises a control module connected with the first sensor, a switching value liquid level processing module connected with the first sensor and the second sensor, and an analog quantity liquid level processing module connected with the analog quantity liquid level detector; the switching value liquid level processing module is used for calculating and outputting a switching value liquid level signal to the control module according to the received thermal diffusion type switching value liquid level signal and based on a thermal diffusion principle; the control module is used for judging whether the water level of the water tank contacts a liquid level switch of a second sensor which is correspondingly arranged, judging that a water temperature signal measured by the temperature sensor is an effective water temperature signal if the water level of the water tank contacts the liquid level switch of the second sensor, and outputting the water temperature signal; control module still is used for surveying the actual liquid level height in pond through analog quantity liquid level processing module control analog quantity liquid level detector, and analog quantity liquid level detector is based on the guided wave radar level gauge output analog quantity liquid level signal of time domain reflection principle extremely control module, through control module calculates and obtains the actual liquid level height in spentnuclear fuel pond.
The device also comprises a display alarm module connected to the control module; the control module is also used for comparing the received actually measured water temperature signal with a preset water temperature signal and outputting an alarm signal according to the comparison result; the display alarm module is used for receiving the alarm signal and outputting a temperature signal of the spent fuel pool.
The processing and transmitting unit further comprises a power supply and power control module, a switching value liquid level processing module and an analog value liquid level processing module, wherein the power supply and power control module is used for controlling the power supply power of the heating resistor of the second sensor and supplying power to the guided wave radar liquid level detector; the control module, the switching value liquid level processing module, the analog value liquid level processing module and the power supply and power control module are all integrated in the processing transmitting unit.
The system comprises a spent fuel pool, a temperature/switching value liquid level acquisition assembly, an analog quantity liquid level detector, a temperature/switching value liquid level acquisition assembly, a first anti-seismic support and a second anti-seismic support, wherein the first anti-seismic support and the second anti-seismic support are fixedly connected to an upper platform of the spent fuel pool respectively, the temperature/switching value liquid level acquisition assembly is fixed to the first anti-seismic support, the analog quantity liquid level detector is fixed to the second anti-seismic support, and a preset distance is reserved between the analog quantity liquid level detector and the temperature/switching value liquid level acquisition assembly.
The first anti-seismic support is provided with a first mounting plate, the first mounting plate is welded with a protection tube extending along the direction of the bottom of the water pool, the protection tube is used for protecting a temperature/switching value liquid level acquisition assembly, the temperature/switching value liquid level acquisition assembly is of an armored structure of a stainless steel tube, and a first sensor and a second sensor which are arranged in pairs are arranged at positions corresponding to different water level heights in the armored stainless steel tube body; the device comprises a pipe body, a plurality of first sensors and a plurality of second sensors, a pair of double branch heating resistors and a controller, wherein the first sensors and the second sensors which are arranged in pairs along the cross section direction of the pipe body are symmetrically arranged along two sides of the center in the pipe body, and the center in the cross section direction of the pipe body is provided with a pair of double branch heating resistors for measuring the temperature of a medium at the lowest position in a spent fuel water pool; the second is resisted and is shaken the support and is provided with the second mounting panel, have the guided wave pole that extends along pond bottom direction on the second mounting panel, guided wave radar level gauge measurement sensing unit includes radar wave transmission and receiving arrangement, and the sensing unit is used for sending the radar wave along the guided wave pole, and when the radar wave contact liquid level reflection, and the sensing unit still is used for receiving the radar wave of reflection back.
The analog quantity liquid level detector also comprises a high-speed timing module and a signal processing and converting module, wherein the high-speed timing module calculates the time difference between the emission and the reflection of the radar waves, the high-speed timing module, the signal processing and converting module and the radar wave emitting and receiving device are of a split structure, the high-speed timing module and the signal processing and converting module are integrated in a processing and transmitting unit, and the radar wave emitting and receiving device is arranged on the second mounting plate.
Wherein, each first sensor that sets up in pairs that different elevation set up is platinum resistance temperature sensor, the second sensor is platinum resistance temperature sensor who has heating resistor
The invention also provides a comprehensive monitoring method for the spent fuel pool of the nuclear power station, which comprises the following steps: acquiring A-grade platinum thermal resistance temperature signals of different elevations of a spent fuel pool of a nuclear power station, acquiring another A-grade platinum thermal resistance temperature signal of a corresponding elevation point, and calculating to obtain a thermal diffusion type switching value liquid level signal based on a thermal diffusion principle; sending out radar waves, receiving the returned radar waves, and detecting the liquid level of the spent fuel pool; and judging whether the received temperature signal is an effective water temperature signal or not according to the received thermal diffusion type switching value liquid level signal, and displaying the height of the liquid level of the water pool and the water temperature.
The method comprises the following steps that a first sensor is used for collecting a water temperature signal with the height of the first sensor, a second sensor with the same height, which is correspondingly arranged with the first sensor, is used for collecting a temperature signal after being heated, and a thermal diffusion type switching value liquid level signal is calculated and output based on a thermal diffusion principle; judging whether the water level of the water pool contacts a second sensor switching value liquid level sensor which is correspondingly arranged, if so, judging that a water temperature signal measured by a corresponding temperature sensor with a standard height is an effective water temperature signal, and outputting a water temperature signal; the analog quantity liquid level detector detects the actual liquid level height of the pool, the guided wave radar liquid level meter based on the time domain reflection principle outputs an analog quantity liquid level signal, and the actual liquid level height of the spent fuel pool is obtained through calculation.
The technical scheme provided by the embodiment of the invention has the following beneficial effects:
the liquid level measurement of the spent fuel pool adopts a thermal diffusion type and guided wave radar diversified measurement technology, so that the liquid level of the spent fuel pool can be accurately obtained under various working conditions, and the safety of the spent fuel pool is ensured; the temperature measurement and the thermal diffusion type liquid level measurement are integrated into an armored assembly, so that the installation and maintenance are more convenient, and the reliability is higher; the non-heating element of the thermal diffusion type liquid level measurement can measure the water temperatures of different elevations at the same time, and can detect whether hot spots exist at different elevations of the water pool or not; the processing and transmitting unit simultaneously receives the temperature signal, the thermal diffusion type switching value liquid level signal and the liquid level signal of the analog quantity liquid level detector, and judges whether the received temperature signal is an effective water temperature signal or not according to the received thermal diffusion type switching value liquid level signal; when the liquid level of the spent fuel pool is continuously detected or the effective water temperature signal exceeds the set temperature value according to judgment, the analog quantity liquid level detector is controlled to measure the liquid level height of the spent fuel pool, and the analog quantity liquid level detector is started to detect by means of judging firstly and then controlling the analog quantity liquid level detector, so that the energy can be saved, the analog quantity liquid level detector only detects when needed, and the service life of the liquid level detector is prolonged. The anti-seismic support is further adopted, the mounting plate adopts a sliding groove type mounting mode, the mounting is convenient and reliable, and foreign matters are prevented from entering the spent fuel pool in the mounting and replacing processes.
Drawings
Fig. 1 is a schematic diagram of a control system of a nuclear power plant spent fuel pool comprehensive monitoring system according to an embodiment of the present invention.
Fig. 2 is a schematic structural diagram of a comprehensive monitoring system for a spent fuel pool according to an embodiment of the present invention.
Fig. 3A is a schematic structural diagram of a first anti-seismic support according to a second embodiment of the present invention.
Fig. 3B is a schematic structural diagram of the top view of fig. 3A.
Fig. 4 is a schematic structural diagram of a first mounting plate according to a second embodiment of the present invention.
Fig. 5 is a schematic diagram of a distribution structure of temperature sensors arranged in pairs at different elevations inside a protection tube according to a second embodiment of the present invention.
Fig. 6 is a schematic flow chart of a comprehensive monitoring method for a spent fuel pool of a nuclear power plant according to a third embodiment of the present invention.
Fig. 7 is another schematic flow chart of a comprehensive monitoring method for a spent fuel pool of a nuclear power plant according to a third embodiment of the present invention.
Fig. 8 is a schematic flow chart of a further method for comprehensively monitoring a spent fuel pool of a nuclear power plant according to a third embodiment of the present invention.
Detailed Description
In order to solve the technical problems of scattered acquisition, inconvenient installation and replacement of parameter measurement of a spent fuel pool of a nuclear power station, single signal source of liquid level measurement and inaccurate measurement under certain working conditions in the prior art, the invention aims to provide a comprehensive monitoring system and a method of the spent fuel pool of the nuclear power station, and the core idea of the comprehensive monitoring system is as follows: utilize this monitoring system to realize the comprehensive monitoring to nuclear power station spent fuel pond, it includes: collecting temperature and liquid level measurement signals of different elevations of the spent fuel pool, outputting the temperature of the spent fuel pool, and outputting an alarm signal based on a comparison result; calculating and outputting a switching value liquid level signal based on a thermal diffusion principle; processing a guided wave radar liquid level meter output analog quantity liquid level signal based on a time domain reflection principle; and controlling the power supply of the heating resistor of the thermal diffusion type liquid level meter and supplying power to the guided wave radar liquid level detector and the processing and transmitting unit. The invention obtains the liquid level parameter of the spent fuel pool by applying the mature platinum thermal resistance temperature measurement technology, the thermal diffusion type liquid level measurement technology and the guided wave radar liquid level measurement technology to the temperature and liquid level measurement of the spent fuel pool of the nuclear power station and adopting diversified measurement means of the thermal diffusion type liquid level measurement and the guided wave radar liquid level measurement, solves the technical problems that the liquid level measurement has single signal source and inaccurate measurement under certain working conditions, and simultaneously integrates the acquired information together to realize integrated installation and signal acquisition, so that an operator can accurately and quickly obtain a plurality of parameters such as the temperature/liquid level of the spent fuel pool in various working conditions, a control system or the operator can take corresponding measures, and the safety of the spent fuel pool is ensured.
In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
Example one
The embodiment of the invention provides a comprehensive monitoring system for a spent fuel pool of a nuclear power station, and the reference figure 1 is a schematic structural diagram of a control system module of the first embodiment of the invention, and the control system comprises: the temperature/switching value liquid level acquisition assembly 10 is characterized in that thermal resistance assemblies are respectively arranged in an armored stainless steel pipe from top to bottom along different elevations of a spent fuel pool and are used for acquiring and transmitting temperature signals (temperature acquisition signals) of a plurality of liquid levels of the pool and thermal diffusion type switching value liquid level signals in real time; the analog quantity liquid level detector 20 is arranged in parallel with the temperature/switching quantity liquid level acquisition assembly 10 and is inserted into the pool body of the spent fuel pool for continuously detecting the liquid level of the spent fuel pool; and the processing transmitting unit is respectively connected with the temperature/switching value liquid level acquisition assembly 10 and the analog quantity liquid level detector 20, and is used for receiving a temperature signal, a thermal diffusion switching value liquid level signal and a liquid level signal of the analog quantity liquid level detector, judging whether the received temperature signal is an effective water temperature signal according to the received thermal diffusion switching value liquid level signal, and displaying the height of the liquid level of the water pool and the water temperature. Or when judging whether the received temperature signal is an effective water temperature signal, the automatic control analog quantity liquid level detector starts to measure the liquid level height of the spent fuel pool, the design has the advantages that the analog quantity liquid level detector is not needed to measure continuously in real time, the analog quantity liquid level detector is controlled to detect the real water level when the effective water temperature signal is received according to the processing and transmitting unit, the liquid level detector is prevented from being in a working state all the time, electric energy is wasted, and the service life is prolonged. Further, temperature/switching value liquid level acquisition subassembly 10 is including setting up respectively a plurality of thermal resistance sensor subassembly of the different elevation position departments of spent fuel pond, each thermal resistance sensor subassembly all includes the first temperature sensor 101 and the second sensor 102 of not taking heating resistor that sets up in pairs, and the first sensor 101 of not taking heating resistor of same elevation is used for gathering the temperature signal of self elevation, corresponds the temperature signal after the same elevation second sensor 102 that sets up with it simultaneously and is used for gathering corresponding pond mark high heat diffusion behind the heating, calculates the thermal diffusion formula switching value liquid level signal who obtains this elevation according to the temperature signal that first sensor 101 and second sensor 102 gathered.
Referring to fig. 2, the analog quantity liquid level detector 20 includes a guided wave radar level gauge measurement sensing unit, which is arranged at the top of the pool and is used for sending and receiving guided wave radar analog quantity liquid level signals under the control of the processing and transmitting unit; the processing and transmitting unit receives the temperature signal of the first sensor 101 and the thermal diffusion type switching value liquid level signal calculated by the first sensor 101 and the second sensor 102, and judges whether the received temperature signal is a valid water temperature signal according to the received thermal diffusion type switching value liquid level signal; and when the water level of the pool is contacted with the second sensor with the corresponding elevation, the received temperature signal is judged to be an effective water temperature signal, and the liquid level height of the spent fuel pool is calculated according to the time difference of sending and receiving the guided wave radar analog quantity liquid level signal.
With further reference to FIG. 1, the process transmitter unit includes a control module 30 coupled to a first sensor 101, a switching value level processing module 40 coupled to the first sensor 101 and a second sensor 102, and an analog level processing module 50 coupled to the analog level detector 20; the switching value liquid level processing module 40 is used for calculating and outputting a switching value liquid level signal to the control module 30 according to the received thermal diffusion type switching value liquid level signal and based on a thermal diffusion principle; the control module 30 is configured to determine whether the water level of the pool contacts a liquid level switch of the second sensor 102, and if the water level contacts the liquid level switch of the second sensor 102, determine that the water temperature signal measured by the temperature sensor 101 is an effective water temperature signal, and output the water temperature signal; the control module 30 is further configured to control the analog quantity liquid level detector 20 to detect the actual liquid level of the pool through the analog quantity liquid level processing module 50, the analog quantity liquid level detector 20 outputs an analog quantity liquid level signal to the control module 30 based on a guided wave radar liquid level meter of a time domain reflection principle, and the actual liquid level of the spent fuel pool is calculated through the control module 30. Also included in FIG. 1 is a display alarm module coupled to control module 30; the control module 30 is further configured to compare the received actually measured water temperature signal with a preset water temperature signal, and output an alarm signal according to the comparison result; the display alarm module is used for receiving the alarm signal and outputting a temperature signal of the spent fuel pool. With reference to fig. 1, the processing and transmitting unit further includes a power supply and power control module 60, configured to control power supplied to the heating resistor of the second sensor 102, and supply power to the guided wave radar level detector 20, the control module 30, the switching value level processing module 40, and the analog value level processing module 50, respectively; in order to realize the high integration level of the invention, the control module 30, the switching value liquid level processing module 40, the analog quantity liquid level processing module 50 and the power supply and power control module 60 are all integrated in the processing and transmitting unit, and the acquired temperature and water level signals are transmitted to the processing and transmitting unit through the radiation-resistant cable 1 and the radiation-resistant cable 2 respectively, so that the invention aims of high integration level, and rapid and accurate data transmission are realized.
In the specific implementation process of this embodiment, in order to obtain the parameter state of the spent fuel pool, a temperature sensor and a level meter need to be installed on the spent fuel pool. According to the condition that the water level of a spent fuel pool is generally lower than 100 ℃, a platinum thermal resistance temperature sensor with stable performance and mature application is generally selected, and the obtained signal is a resistance signal; according to the spent fuel pool depth and exceeding 8 meters, and have the characteristics of higher irradiation dose under extreme operating mode, general spent fuel pool level gauge is thermal diffusion formula level gauge and guided wave radar level gauge, and according to the difference of its principle and characteristic, if thermal diffusion formula level gauge output signal is resistance, the time difference of guided wave radar level gauge echo and transmitting wave is directly proportional with the distance of probe to liquid level, so need handle the measuring signal of temperature sensor and level gauge output, obtain more audio-visual temperature and liquid level value. Further, the values of two thermal resistors at the same liquid level elevation of the thermal diffusion type liquid level meter need to be calculated and compared, a thermal diffusion type switching value signal is output, and the thermal diffusion type liquid level meter can be used for alarming the height of the water level; in addition, in order to determine that the obtained temperature value is an effective value, the judgment needs to be performed according to a liquid level switch signal corresponding to the altitude, and the corresponding temperature value is only an effective temperature value when the corresponding altitude has water. One of the best modes of the invention is as follows: each first sensor that sets up in pairs that different elevations set up is platinum resistance temperature sensor, the second sensor is platinum resistance temperature sensor who has heating resistor. The liquid level measurement of the spent fuel pool adopts the thermal diffusion type and guided wave radar diversified measurement technology, the liquid level of the spent fuel pool can be accurately obtained under various working conditions, and the safety of the spent fuel pool is ensured; the temperature measurement and the thermal diffusion type liquid level measurement are integrated into a component, so that the installation and maintenance are more convenient, and the reliability is higher; the non-heating element of the thermal diffusion type liquid level measurement can measure the water temperatures of different elevations at the same time, and can detect whether hot spots exist at different elevations of the water pool.
Example two
The embodiment of the invention provides a comprehensive monitoring system for a spent fuel pool of a nuclear power station, and in comparison with the first embodiment, referring to an attached drawing 2, the comprehensive monitoring system further comprises a first anti-seismic support 1 and a second anti-seismic support 2 which are fixedly connected to an upper platform of the spent fuel pool respectively, wherein a temperature/switching value liquid level acquisition assembly 10 is fixed on the first anti-seismic support 1, an analog value liquid level detector 20 is fixed on the second anti-seismic support 2, and a preset distance is reserved between the analog value liquid level detector 20 and the temperature/switching value liquid level acquisition assembly 10; the accuracy of the measuring signal can be ensured by setting the preset distance, and the preset distance is as follows: the installation distance between the measurement sensing unit of the guided wave radar liquid level meter and the measurement sensing unit of the temperature/thermal diffusion type liquid level switch is kept above 300mm, so that a detection rod of the measurement sensing unit of the temperature/thermal diffusion type liquid level switch is prevented from interfering the measurement of the guided wave radar liquid level meter to form false signals.
Further, as shown in fig. 3A and 3B, first antidetonation support 1 is the type of bending, it forms to bend with 10 mm's 304L corrosion resistant plate, including horizontal support plate 1a, horizontal support plate 1a is last to have four spouts 1B, with horizontal support plate 1a fixed connection's fixed plate 1d, and the welding has strengthening rib 1c, a intensity for strengthening first antidetonation support 1, antidetonation support 1 has seted up four fixed orificess 1e through fixed plate 1d and has fixed on the floor on spent fuel pond upper portion, antidetonation support 1 carries out intensity and atress preliminary analysis through ANSYS finite element analysis software, finally carry out the test verification on the platform of combatting earthquake.
Combine the attached figure 4 to show, still including setting up horizontal support plate 1a and with the first mounting panel 3 that horizontal support plate 1a corresponds, first mounting panel 3 corresponds with four spouts 3b of first mounting panel 3 with four spouts 1b of horizontal support plate 1a on the antidetonation support 1, through bolted connection between the two, when temperature/switching value liquid level acquisition subassembly or analog quantity liquid level detector dismouting, fixing bolt need not take off, unscrew can. The first mounting plate 3 is fixed on a temperature/switching value liquid level acquisition assembly or an analog quantity liquid level detector and then is hoisted to the anti-seismic support 1. The first mounting plate 3 penetrates through the large hole of the first mounting plate together with the fixing bolt (including the upper fixing nut) of the anti-seismic support 1, and the fixing bolt slides to the small hole through the corresponding sliding groove to be fixed. Due to the adoption of the anti-seismic support, the equipment is ensured to be available under the earthquake condition; the adoption of the sliding groove type mounting plate not only facilitates the installation and reduces the workload of the disassembly and assembly, but also can prevent foreign matters such as bolts and the like from falling into the spent fuel pool in the installation process.
Referring to fig. 4, which is a schematic structural diagram of the first mounting plate, a protection tube extending along the bottom direction of the pool is welded at a central hole of the first mounting plate 3, and the protection tube is used for protecting the temperature/switching value liquid level acquisition assembly; the temperature/switching value liquid level acquisition assembly is of an armored structure of a stainless steel pipe, and a first sensor and a second sensor which are arranged in pairs are arranged at the positions corresponding to different water level elevations in the armored stainless steel pipe body; the device comprises a pipe body, a plurality of first sensors and a plurality of second sensors, a pair of double branch heating resistors and a controller, wherein the first sensors and the second sensors which are arranged in pairs along the cross section direction of the pipe body are symmetrically arranged along two sides of the center in the pipe body, and the center in the cross section direction of the pipe body is provided with a pair of double branch heating resistors for measuring the temperature of a medium at the lowest position in a spent fuel water pool; the second is resisted and shakes the support and is provided with the second mounting panel, guided wave radar level gauge measurement sensing unit includes radar wave transmission and receiving arrangement and the guided wave pole that extends along pond bottom direction, and sensing unit is used for sending out the radar wave along the guided wave pole, and when the radar wave contact liquid level reflection, and sensing unit still is used for receiving the radar wave of reflection back. It should be noted that the structure, material and connection relationship between the second anti-seismic support and the second mounting plate are the same as the structure, material and connection relationship between the first anti-seismic support and the first mounting plate, so the drawings are omitted here and will not be explained in further detail. The first and second shock-proof supports and the first and second mounting plate supports are in a sliding groove structure.
Furthermore, the analog quantity liquid level detector also comprises a high-speed timing module and a signal processing and converting module, wherein the high-speed timing module calculates the time difference between the emission and the reflection of the radar waves, the high-speed timing module, the signal processing and converting module and the radar wave emitting and receiving device are of a split structure, the high-speed timing module and the signal processing and converting module are integrated in the processing and transmitting unit, and the radar wave emitting and receiving device is fixedly connected to the second mounting plate. By integrating the high-speed timing module and the signal processing and converting module in the analog quantity liquid level detector into the processing and transmitting unit, the integration level of the system is further improved, and the data calculation and transmission are direct, accurate and effective.
As further shown in fig. 2, two such integrated monitoring devices may be disposed for each spent fuel pool. The temperature/switching value liquid level acquisition assembly and the upper part of the detector are fixed on the corresponding anti-seismic supports through the corresponding mounting plates, each anti-seismic support is respectively installed on the upper platform of the spent fuel pool, the lower part of the pool wall is a free end, the lower part of the pool wall is provided with an annular structure which is sleeved outside the corresponding tube body, the amplitude of the temperature/switching value liquid level acquisition assembly and the amplitude of the guided wave rod body swinging along the radial direction are reduced, the measurement reliability is improved, and the annular structure at the lower part of the pool wall can be omitted in the transformation project of the in-service power station. Further, the thermal diffusion level measurement is based on the thermal diffusion formula α ═ λ/ρ c (formula 1), where α is the thermal diffusivity or thermal diffusion coefficient (thermal diffusion) in m2(s), wherein:
λ: thermal conductivity, unit W/m.K;
ρ: density in kg/m3；
c: heat capacity, unit J/kg.K.
As can be seen from the formula 1, the larger the thermal conductivity coefficient lambda of an object is, the more heat can be conducted under the same temperature gradient; the smaller rho c is, the smaller the heat absorbed by the temperature rise of 1 ℃ is, more heat can be left to be continuously transferred to the interior of the object, and the temperature of each point of the object can rise faster along with the rise of the interface temperature.
For example, at 20 deg.C, the thermal conductivity of water is 0.599W/m.K, the air is 0.0267W/m.K, and the density of water is about 1000kg/m3Heat capacity of 4.2X 103J/kg.K, air density of about 1.29kg/m3Heat capacity of 1X 103K, it can be seen that water has a thermal conductivity of about 22 times that of air and a pc value of about 3256 times that of air. Therefore, if the heating resistor maintains the deviation of the heated RTD and the unheated RTD at 20 ℃ in the air, the spot is immersedWhen submerged in water, thermal equilibrium is reached very quickly and the temperature difference is well below 20 ℃. In this way it is possible to determine whether there is water at the level.
The temperature/switching value liquid level acquisition assembly comprises a plurality of temperature/switching value liquid level acquisition assemblies which are arranged at different elevations in pairs along the interior of a stainless steel pipe, each reference RTD (thermal resistance temperature sensor) of a thermal diffusion type liquid level switch is individually sheathed, an RTD element and a heating resistor in a heating RTD (namely a second sensor 102) are sheathed together, and the reference RTD (a first sensor 101) and the heating RTD (a second sensor) at the same elevation point are symmetrically arranged, so that the measurement accuracy is ensured, and the heating resistor does not influence the reference RTD. The thermal diffusion type water level measuring armor wire and the bottommost temperature measuring armor wire are fixed together in a stainless steel tube, and high-purity magnesium oxide is filled and compacted. This provides a high reliability of the temperature/switching value level acquisition assembly. Taking 3 low water level alarms and one high water level alarm as an example, as shown in fig. 5, a pair of temperature sensors of an RTD1-1 and an RTD1-2+ R1 are used for high water level alarm, and are symmetrically arranged with the same installation elevation, wherein the RTD1-1 is a reference RTD, the R1 is a heating resistor, the RTD1-2 is sheathed with the heating resistor R1, the R1 heats at a certain power, and the RTD1-2 measures the heated temperature; similarly, the RTD2-1 and the RTD2-2+ R2 are in a group and are used for low-one value alarm; the RTD3-1 and the RTD3-2+ R3 are in a group and are used for low binary alarm or interlocking; RTD4-1 and RTD4-2+ R4 are in one group and are used for low ternary interlocking; the RTD5-1 and the RTD5-2 are two thermal resistors and are installed at the position of the lowest water level of the pipe body and used for measuring the temperature of the medium of the spent fuel pool in real time.
Further, referring to fig. 2, a control module, a switching value liquid level processing module, an analog value liquid level processing module (including a high-speed timing module and a signal processing conversion module) and a power supply and power control module are all integrated in the processing and transmitting unit. The measurement sensing unit is connected with the processing and transmitting unit through an irradiation-resistant cable, and the measurement sensing unit is connected with the cable through a quick connector, so that the measurement sensing unit can be maintained and replaced quickly.
The thermal resistance signal is sent to the processing transmitting unit through the irradiation-resistant cable, a graduation meter of the Pt100 platinum thermal resistance is arranged in a control module in the processing transmitting unit, furthermore, in order to improve the temperature measurement precision, a personalized graduation meter corresponding to a temperature element can be arranged in the control module, but the data processing quantity can be increased, the measurement of a general spent fuel pool does not need the high measurement precision, and a standard graduation meter is arranged in the control module. After being processed by the control module, the signal of 4-20 mA can be sent to the DCS control system.
The reference RTD of each elevation point is combined with a water signal to carry out logic judgment to determine whether the signal is sent out as a temperature signal, and the logic judgment can be processed in a processing transmitting unit or sent to a DCS (distributed control system) to carry out logic judgment and then determine whether the signal is displayed.
The external access power supply is 220VAC, furthermore, in order to ensure the reliability of the access power supply, two paths of 220VAC can be accessed, and a double-power-supply switching device is added. The power supply and power control module converts 220VAC power supply into voltage required by a circuit board, a heating resistance wire, a guided wave radar liquid level meter and the like.
The analog quantity liquid level signal is measured by a guided wave radar liquid level meter. A radar wave is essentially an electromagnetic wave. An electromagnetic wave is transmitted from the medium 1 to the medium 2, and if the dielectric constant of the medium 2 is larger than the dielectric constant 1 of the medium 1, the electromagnetic wave is reflected. The sensing unit of the guided wave radar liquid level meter adopts a coaxial guided wave rod, the sensing unit sends out radar waves along the guided wave rod, when the radar waves are in contact with the liquid level to be reflected, the sensing unit receives the reflected radar waves, the ultra-high speed timing circuit calculates the time difference delta T from emission to reflection, and the distance S from the top of the radar to the liquid level is V delta T/2. In this embodiment, the guided wave radar level gauge adopts split type design, measures the sensing element and only radar wave transmission and receiving arrangement, can still can use under very high irradiation dose. The analog quantity liquid level processing module comprises a high-speed timing module and a signal processing and converting module which are integrated in the processing and transmitting unit. The guided wave radar liquid level detector and the processing and transmitting unit are connected by a special irradiation-resistant coaxial mineral insulated (M I) cable. If the number of cable cores sent to the DCS control system needs to be reduced, a communication module can be added in the processing and transmitting unit, 4-20 mA signals are transmitted to the DCS control system through optical fibers, and switching value liquid level signals are still sent to the DCS control system through hard wiring.
In the second embodiment of the invention, because two anti-seismic supports are arranged at intervals, each mounting plate adopts a sliding groove type mounting mode, the mounting is convenient and reliable, and foreign matters are prevented from entering a spent fuel pool in the mounting and replacing processes. The alternative scheme of the invention can include replacing a platinum thermal resistance temperature element in the thermal diffusion type liquid level measurement with a thermocouple, and can also realize the temperature measurement, wherein the output signal is a millivolt signal, the millivolt signal can be output by adopting a compensation lead, and the millivolt signal can also be converted into standard 4-20 mA.
EXAMPLE III
The third embodiment of the invention provides a comprehensive monitoring method for a spent fuel pool of a nuclear power station, which is suitable for the comprehensive monitoring system for the spent fuel pool of the nuclear power station shown in the first embodiment and the second embodiment, and referring to fig. 6, the method comprises the following steps:
s100, collecting A-grade platinum thermal resistance temperature signals of different elevations of a spent fuel pool of the nuclear power station, collecting another A-grade platinum thermal resistance temperature signal corresponding to the elevation point, and calculating to obtain a thermal diffusion type switching value liquid level signal based on a thermal diffusion principle;
s200, sending out radar waves, receiving returned radar waves, and detecting the liquid level of the spent fuel pool;
s300, judging whether the received temperature signal is an effective water temperature signal or not according to the received thermal diffusion type switching value liquid level signal, and displaying the height of the liquid level of the water pool and the water temperature.
Furthermore, the method comprises the steps of acquiring a water temperature signal of the first sensor with the same standard height, acquiring a temperature signal of a second sensor with the same standard height, which is correspondingly arranged with the first sensor, after heating, and calculating and outputting a thermal diffusion type switching value liquid level signal based on a thermal diffusion principle; judging whether the water level of the water pool contacts a second sensor switching value liquid level sensor which is correspondingly arranged, if so, judging that a water temperature signal measured by a corresponding temperature sensor with a high mark is an effective water temperature signal, and outputting a water temperature signal; the analog quantity liquid level detector detects the actual liquid level height of the pool, the guided wave radar liquid level meter based on the time domain reflection principle outputs an analog quantity liquid level signal, and the actual liquid level height of the spent fuel pool is obtained through calculation.
For the step method of the above further embodiment, more specifically, the method comprises: referring to fig. 7, the method comprises the following steps:
s1, collecting A-level platinum thermal resistance temperature measurement signals of different heights of a spent fuel pool of the nuclear power station; acquiring signals of two A-level platinum thermal resistors (the unheated platinum thermal resistor and the temperature measurement are shared) at each elevation point based on a thermal diffusion type principle (constant power); sending out radar waves and receiving returned radar waves;
s2, converting the A-grade unheated Pt100 platinum thermal resistance signal into a 4-20 mA standard signal; outputting a switching value liquid level alarm signal based on the thermal diffusion type principle; judging whether to output a corresponding standard temperature signal or not based on the switching value liquid level alarm signal; and outputting an analog quantity level signal based on the Time Domain Reflectometry (TDR) principle.
Further, referring to fig. 8, the step S1 specifically includes:
s11, adopting A-grade platinum thermal resistor with good stability, good linearity and high precision as a temperature measuring element;
s12, adopting A-grade platinum thermal resistor with good stability, good linearity and high precision as an element of the thermal diffusion type liquid level switch (the unheated platinum thermal resistor is shared with temperature measurement);
and S13, sending out radar waves and receiving returned radar waves, wherein the radar waves are transmitted along the waveguide rod.
In a specific implementation process, the step S2 specifically includes:
s21, converting the A-level unheated Pt100 platinum thermal resistance signal into a 4-20 mA standard signal to reduce the signal type and the cable core number of the control system, and then sending a temperature signal to the control system for display after judging that a water signal exists through a liquid level switch.
Optionally, after the water signal is judged by the liquid level switch, the temperature signal of the Pt100 platinum thermal resistor is sent to the control system for display.
Optionally, the Pt100 thermal resistance signal is directly sent to the control system, and after logical judgment with the liquid level switch is performed in the control system, whether the temperature value at this point is adopted is determined.
And S22, judging whether water exists or not according to the change of the temperature difference based on the thermal diffusion principle of constant power, and sending a signal to a control system.
And S23, calculating the distance between the probe and the liquid level according to the time difference between the sending time and the returning time of the radar wave, thereby calculating the liquid level.
The present invention provides a computer-readable storage medium storing a computer program which, when executed by a processing transmission unit control module, performs the steps of: s100, collecting A-grade platinum thermal resistance temperature signals of different elevations of a spent fuel pool of the nuclear power station, collecting another A-grade platinum thermal resistance temperature signal corresponding to the elevation point, and calculating to obtain a thermal diffusion type switching value liquid level signal based on a thermal diffusion principle; s200, sending out radar waves, receiving returned radar waves, and detecting the liquid level of the spent fuel pool; s300, judging whether the received temperature signal is an effective water temperature signal or not according to the received thermal diffusion type switching value liquid level signal, and displaying the height of the liquid level of the water pool and the water temperature.
In the computer-readable storage medium, the control module controls the first sensor to collect a water temperature signal with a standard height, collects a temperature signal after being heated by a second sensor with the same standard height and arranged corresponding to the first sensor, and calculates and outputs a thermal diffusion type switching value liquid level signal based on a thermal diffusion principle; judging whether the water level of the water pool contacts a second sensor switching value liquid level sensor which is correspondingly arranged, if so, judging that a water temperature signal measured by a corresponding temperature sensor with a high mark is an effective water temperature signal, and outputting a water temperature signal; the analog quantity liquid level detector detects the actual liquid level height of the pool, the guided wave radar liquid level meter based on the time domain reflection principle outputs an analog quantity liquid level signal, and the actual liquid level height of the spent fuel pool is obtained through calculation.
With reference to the descriptions of the first to third embodiments, the spent fuel pool liquid level measurement of the invention adopts a thermal diffusion type and guided wave radar diversified measurement technology; the thermal diffusion type liquid level measurement mode outputs a switching value signal after being processed for alarming or interlocking; the guided wave radar liquid level measurement mode outputs analog quantity signals after being processed, and the analog quantity signals are used for continuously monitoring the liquid level of the spent fuel pool. The liquid level of the spent fuel pool is monitored by two completely different technologies, and different types of signals (respectively, switching value and analog value) are output, so that the common cause failure risk can be greatly reduced. The temperature measurement and the thermal diffusion type liquid level measurement are integrated into a component; the measuring element of the thermal diffusion type liquid level measurement is also a platinum thermal resistor, is consistent with the element adopted by temperature measurement, is manufactured into an armored form, has high reliability, is integrated into one component, is convenient to install and replace, and improves the mechanical strength and reliability of the device. The guided wave radar level gauge adopts a split structure. The guided wave radar liquid level meter adopts a split type design, and an analog quantity liquid level detector only has a radar wave transmitting and receiving device and can still be used under the very high irradiation dose (1 MGy). The high-speed timing module and the signal processing conversion module are both arranged in the processing and transmitting unit. The guided wave radar liquid level detector and the processing and transmitting unit are connected by a special irradiation-resistant coaxial Mineral Insulated (MI) cable. Therefore, the guided wave radar liquid level meter can still perform reliable measurement under the working condition of a spent fuel accident (high irradiation dose and high-temperature and high-humidity environment). Adopt antidetonation support, the mounting panel adopts the slotted mounting means. Due to the adoption of the anti-seismic support, the equipment is ensured to be available under the earthquake condition; the adoption of the sliding groove type mounting plate not only facilitates the installation and reduces the workload of the disassembly and assembly, but also can prevent foreign matters such as bolts and the like from falling into the spent fuel pool in the installation process.
It should be noted that the comprehensive monitoring system, method and storage medium for the spent fuel pool of the nuclear power plant belong to the same inventive concept. It will be understood by those skilled in the art that all or part of the processes of the methods of the embodiments described above can be implemented by a computer program, which can be stored in a non-volatile computer-readable storage medium, and can include the processes of the embodiments of the methods described above when the program is executed. Any reference to memory, storage, database, or other medium used in the embodiments provided herein may include non-volatile and/or volatile memory, among others. Non-volatile memory can include read-only memory (ROM), Programmable ROM (PROM), Electrically Programmable ROM (EPROM), Electrically Erasable Programmable ROM (EEPROM), or flash memory. Volatile memory can include Random Access Memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), Double Data Rate SDRAM (DDRSDRAM), Enhanced SDRAM (ESDRAM), Synchronous Link DRAM (SLDRAM), Rambus Direct RAM (RDRAM), direct bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM). The above-mentioned serial numbers of the embodiments of the present invention are merely for description and do not represent the merits of the embodiments.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (10)
1. The utility model provides a nuclear power station spent fuel pond integrated monitoring system which characterized in that includes:
the temperature/switching value liquid level acquisition assemblies are respectively arranged from top to bottom along different elevations of the spent fuel pool and are used for acquiring and transmitting temperature signals of a plurality of liquid levels of the pool and thermal diffusion type switching value liquid level signals in real time;
the analog quantity liquid level detector is arranged in parallel with the temperature/switching quantity liquid level acquisition assembly and is inserted into the pool body of the spent fuel pool to continuously detect the liquid level of the spent fuel pool;
the processing and transmitting unit is respectively connected with the temperature/switching value liquid level acquisition assembly and the analog quantity liquid level detector, and is used for receiving the temperature signal, the thermal diffusion switching value liquid level signal and the liquid level signal of the analog quantity liquid level detector, judging whether the received temperature signal is an effective water temperature signal according to the received thermal diffusion switching value liquid level signal, and displaying the liquid level height and the water temperature of the water pool;
the temperature/switching value liquid level acquisition assembly comprises a plurality of thermal resistance sensor assemblies which are respectively arranged at different elevation positions of the spent fuel pool, each thermal resistance sensor assembly comprises a first sensor and a second sensor which are arranged in pairs, the first sensor at the same elevation position is used for acquiring a water temperature signal at the same elevation position, the second sensor at the same elevation position, which is correspondingly arranged, is used for acquiring a water temperature signal after high heat diffusion of the corresponding pool after heating, and the switching value liquid level signal at the elevation position is calculated according to the water temperature signals acquired by the first sensor and the second sensor;
the analog quantity liquid level detector comprises a guided wave radar liquid level meter measuring and sensing unit, is arranged at the top of the water pool and is used for sending and receiving guided wave radar analog quantity liquid level signals under the control of the processing and transmitting unit;
the processing and transmitting unit is further used for receiving the temperature signals and the thermal diffusion type switching value liquid level signals, judging whether the received temperature signals are effective water temperature signals or not according to the received thermal diffusion type switching value liquid level signals, and calculating the liquid level height of the spent fuel pool according to the time difference of sending and receiving the guided wave radar analog quantity liquid level signals.
2. The monitoring system of claim 1, wherein the processing and transmitting unit includes a control module coupled to the first sensor, a switching value level processing module coupled to the first sensor and the second sensor, and an analog level processing module coupled to the analog level detector;
the switching value liquid level processing module is used for calculating and outputting a switching value liquid level signal to the control module according to the received thermal diffusion type switching value liquid level signal and based on a thermal diffusion principle;
the control module is used for judging whether the water level of the water tank contacts a liquid level switch of a second sensor which is correspondingly arranged, and if the water level switch of the second sensor is contacted, judging that a water temperature signal measured by the temperature sensor is an effective water temperature signal, and outputting a water temperature signal;
control module still is used for surveying the actual liquid level height in pond through analog quantity liquid level processing module control analog quantity liquid level detector, and analog quantity liquid level detector is based on the guided wave radar level gauge output analog quantity liquid level signal of time domain reflection principle extremely control module, through control module calculates and obtains the actual liquid level height in spentnuclear fuel pond.
3. The monitoring system of claim 2, further comprising a display alarm module connected to the control module; the control module is also used for comparing the received actually measured water temperature signal with a preset water temperature signal and outputting an alarm signal according to the comparison result; the display alarm module is used for receiving the alarm signal and outputting a temperature signal of the spent fuel pool.
4. The monitoring system of claim 2, wherein the processing and transmitting unit further comprises a power supply and power control module for controlling the power supply of the heating resistor of the second sensor and supplying power to the guided wave radar level detector, the control module, the switching value level processing module and the analog value level processing module; the control module, the switching value liquid level processing module, the analog value liquid level processing module and the power supply and power control module are all integrated in the processing transmitting unit.
5. The monitoring system according to claim 4, further comprising a first anti-seismic support and a second anti-seismic support, wherein the first anti-seismic support and the second anti-seismic support are fixedly connected to the upper spent fuel pool platform, the temperature/switching value liquid level acquisition assembly is fixed to the first anti-seismic support, the analog value liquid level detector is fixed to the second anti-seismic support, and a preset distance is formed between the analog value liquid level detector and the temperature/switching value liquid level acquisition assembly.
6. The monitoring system according to claim 5, wherein a first mounting plate is arranged on the first anti-seismic support, a protection pipe which extends along the bottom direction of the water tank is welded on the first mounting plate, the protection pipe is used for protecting the temperature/switching value liquid level acquisition assembly, the temperature/switching value liquid level acquisition assembly is of an armored structure of stainless steel pipes, and a first sensor and a second sensor which are arranged in pairs are arranged at positions corresponding to different water level heights in the armored stainless steel pipe body;
the device comprises a pipe body, a plurality of first sensors and a plurality of second sensors, a pair of double branch heating resistors and a controller, wherein the first sensors and the second sensors which are arranged in pairs along the cross section direction of the pipe body are symmetrically arranged along two sides of the center in the pipe body, and the center in the cross section direction of the pipe body is provided with a pair of double branch heating resistors for measuring the temperature of a medium at the lowest position in a spent fuel water pool;
the second anti-seismic support is provided with a second mounting plate, the second mounting plate is provided with a guided wave rod extending along the bottom direction of the water tank, the guided wave radar level gauge measurement sensing unit comprises a radar wave transmitting and receiving device, the sensing unit is used for transmitting radar waves along the guided wave rod, and when the radar waves contact the liquid level to be reflected, the sensing unit is also used for receiving the reflected radar waves;
and a sliding groove type structure is adopted between each anti-seismic support and the corresponding mounting plate support.
7. The monitoring system of claim 6, wherein the analog level detector further comprises a high speed timing module and a signal processing and converting module, the high speed timing module calculates the time difference between the emission and the reflection of the radar wave, the high speed timing module and the signal processing and converting module and the radar wave emitting and receiving device are in a split structure, the high speed timing module and the signal processing and converting module are integrated in a processing and transmitting unit, and the radar wave emitting and receiving device is arranged on the second mounting plate.
8. The monitoring system of claim 1, wherein each paired first sensor of a different elevation setting is a platinum thermistor temperature sensor and the second sensor is a platinum thermistor temperature sensor having a heating resistor.
9. A comprehensive monitoring method for a spent fuel pool of a nuclear power plant, which adopts the monitoring system as claimed in any one of claims 1 to 8, and is characterized by comprising the following steps:
acquiring A-grade platinum thermal resistance temperature signals of different elevations of a spent fuel pool of a nuclear power station, acquiring another A-grade platinum thermal resistance temperature signal of a corresponding elevation point, and calculating to obtain a thermal diffusion type switching value liquid level signal based on a thermal diffusion principle;
sending out radar waves, receiving the returned radar waves, and detecting the liquid level of the spent fuel pool;
and judging whether the received temperature signal is an effective water temperature signal or not according to the received thermal diffusion type switching value liquid level signal, and displaying the height of the liquid level of the water pool and the water temperature.
10. The monitoring method according to claim 9, wherein a first sensor is used for collecting a water temperature signal with a self elevation, a second sensor with the same elevation arranged correspondingly to the first sensor is used for collecting a temperature signal after being heated, and a thermal diffusion type switching value liquid level signal is calculated and output based on a thermal diffusion principle;
judging whether the water level of the water pool contacts a second sensor switching value liquid level sensor which is correspondingly arranged, if so, judging that a water temperature signal measured by a corresponding temperature sensor with a standard height is an effective water temperature signal, and outputting a water temperature signal; the analog quantity liquid level detector detects the actual liquid level height of the pool, the guided wave radar liquid level meter based on the time domain reflection principle outputs an analog quantity liquid level signal, and the actual liquid level height of the spent fuel pool is obtained through calculation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911017337.2A CN110853781B (en) | 2019-10-24 | 2019-10-24 | Comprehensive monitoring system and method for spent fuel pool of nuclear power station |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911017337.2A CN110853781B (en) | 2019-10-24 | 2019-10-24 | Comprehensive monitoring system and method for spent fuel pool of nuclear power station |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110853781A CN110853781A (en) | 2020-02-28 |
| CN110853781B true CN110853781B (en) | 2021-12-03 |
Family
ID=69596895
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911017337.2A Active CN110853781B (en) | 2019-10-24 | 2019-10-24 | Comprehensive monitoring system and method for spent fuel pool of nuclear power station |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110853781B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112361948B (en) * | 2020-10-29 | 2022-02-22 | 中国核动力研究设计院 | Heating device for simulating different temperature control of fuel rod-spent pool |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2526964Y (en) * | 2001-07-01 | 2002-12-18 | 烟台市招远自动化仪表厂 | Thermal diffusion liquid level switch |
| CN102945686A (en) * | 2012-11-02 | 2013-02-27 | 中国核电工程有限公司 | Spent fuel pool state continuous monitoring method and system |
| WO2013095735A1 (en) * | 2011-10-04 | 2013-06-27 | Westinghouse Electric Company Llc | Pool level indication system |
| EP2706534A1 (en) * | 2012-09-11 | 2014-03-12 | GE-Hitachi Nuclear Energy Americas LLC | Method and system for measuring a spent fuel pool temperature and liquid level without external electrical power |
| CN205282106U (en) * | 2015-11-20 | 2016-06-01 | 国核华清（北京）核电技术研发中心有限公司 | A test device that is used for pond formula to smuggle mechanism research secretly |
| CN106448764A (en) * | 2016-11-24 | 2017-02-22 | 中广核工程有限公司 | System and method for monitoring spent fuel pool of nuclear power plant |
| CN206350252U (en) * | 2016-12-06 | 2017-07-21 | 中广核工程有限公司 | Embedded Touch Screen antidetonation fixed structure |
| CN108225481A (en) * | 2016-12-09 | 2018-06-29 | 国核华清（北京）核电技术研发中心有限公司 | Spent Fuel Pool level monitoring system and method under a kind of more operating conditions |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105957569B (en) * | 2016-07-07 | 2017-12-22 | 中广核研究院有限公司北京分公司 | A kind of nuclear power station spent fuel reservoir monitoring device |
| CN209296066U (en) * | 2019-02-05 | 2019-08-23 | 美核电气（济南）股份有限公司 | A kind of high pressure resistant thermal mass flow meter |
-
2019
- 2019-10-24 CN CN201911017337.2A patent/CN110853781B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2526964Y (en) * | 2001-07-01 | 2002-12-18 | 烟台市招远自动化仪表厂 | Thermal diffusion liquid level switch |
| WO2013095735A1 (en) * | 2011-10-04 | 2013-06-27 | Westinghouse Electric Company Llc | Pool level indication system |
| EP2706534A1 (en) * | 2012-09-11 | 2014-03-12 | GE-Hitachi Nuclear Energy Americas LLC | Method and system for measuring a spent fuel pool temperature and liquid level without external electrical power |
| CN102945686A (en) * | 2012-11-02 | 2013-02-27 | 中国核电工程有限公司 | Spent fuel pool state continuous monitoring method and system |
| CN205282106U (en) * | 2015-11-20 | 2016-06-01 | 国核华清（北京）核电技术研发中心有限公司 | A test device that is used for pond formula to smuggle mechanism research secretly |
| CN106448764A (en) * | 2016-11-24 | 2017-02-22 | 中广核工程有限公司 | System and method for monitoring spent fuel pool of nuclear power plant |
| CN206350252U (en) * | 2016-12-06 | 2017-07-21 | 中广核工程有限公司 | Embedded Touch Screen antidetonation fixed structure |
| CN108225481A (en) * | 2016-12-09 | 2018-06-29 | 国核华清（北京）核电技术研发中心有限公司 | Spent Fuel Pool level monitoring system and method under a kind of more operating conditions |
Non-Patent Citations (2)
| Title |
|---|
| 核电厂乏燃料水池状态监测的设计要求及方案;李珊珊;《科技创业家》;20140430;187-188 * |
| 雷达液位计在乏燃料水池监测中的应用;黄玥;《仪器仪表用户》;20141231;95-97 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110853781A (en) | 2020-02-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0607057B1 (en) | Electrochemical monitoring of vessel penetrations | |
| JP5829527B2 (en) | Reactor water level and temperature measurement device | |
| KR101428404B1 (en) | Nuclear reactor protection system using in-core sensors | |
| US9395227B2 (en) | Reactor water-level measurement system | |
| US20090293608A1 (en) | Apparatus for Measuring a Filling Level | |
| CN105513656A (en) | System and method for monitoring reactor core parameters of nuclear power plant | |
| JP2014530364A (en) | Pool water level indication system | |
| CN110853781B (en) | Comprehensive monitoring system and method for spent fuel pool of nuclear power station | |
| US8831162B2 (en) | Apparatus and method for measuring a temperature of coolant in a reactor core, and apparatus for monitoring a reactor core | |
| US20220084705A1 (en) | Nuclear fuel failure protection method | |
| CN103903661A (en) | After-accident pressurizer water level measurement system and method | |
| KR101484000B1 (en) | Hybrid Incore Detector Assembly for Core Monitoring And Protection using eXtended Length | |
| CN105247620A (en) | Hybrid reactor in-core detector assembly for core monitoring and protection | |
| JP4334124B2 (en) | Reactor digital power range monitoring system | |
| JP2000137093A (en) | Fixed in-pile nuclear instrumentation system of reactor, nuclear instrumentation process, power distribution calculating device and method, and power distribution monitoring system and method | |
| CN107561117A (en) | A kind of hydrogen gas sensor based on thermal conduction principle | |
| KR101549699B1 (en) | Sensing unit and optical fiber sensor apparatus comprising the same | |
| US4634570A (en) | Process and device for measuring the local thermal power in a nuclear reactor | |
| JPH0560560B2 (en) | ||
| CN117346555A (en) | Automatic monitoring and alarming method and device for intermediate frequency equipment | |
| JPH10170685A (en) | Fixed in-core instrumental system | |
| JP2005172474A (en) | Nuclear reactor core thermal output monitoring device | |
| Mitelman | In-core monitoring detectors | |
| Mitelman et al. | Application of assemblies of in-core instruments of the emergency process instrumentation system. The reactor pressure vessel coolant level sensor in Pressurized-Water Reactors | |
| JP2021071313A (en) | Nuclear reactor output monitoring device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |