CN115792407A - Electromagnetic environment early warning system and electromagnetic environment early warning method - Google Patents
Electromagnetic environment early warning system and electromagnetic environment early warning method Download PDFInfo
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Abstract
The invention provides an electromagnetic environment early warning system and a method, wherein the system comprises a frequency domain, a time domain measurement subsystem and a measurement and control server; the frequency domain measurement subsystem comprises a real-time frequency spectrograph, a radio frequency matrix switch, a far field measurement module, a near field measurement module and a conduction measurement module, wherein the far field measurement module, the near field measurement module and the conduction measurement module are used for respectively measuring a far field, a near field and a conduction electromagnetic signal; the output ends of the real-time frequency spectrometers are connected with the radio frequency matrix switch and then connected with the real-time frequency spectrograph, and the real-time frequency spectrometers finish the measurement and analysis of the frequency domain electromagnetic signals and transmit the frequency domain electromagnetic signals to the measurement and control server; the time domain measurement subsystem comprises an oscilloscope and a voltage probe module, wherein the voltage probe module is used for sensing and measuring the fluctuation state of a voltage signal in a target equipment cable and transmitting the voltage signal to the oscilloscope, and the oscilloscope is used for measuring and analyzing a time domain electromagnetic signal and transmitting the time domain electromagnetic signal to the measurement and control server; and the measurement and control server gives an alarm prompt. The electromagnetic risk in the plant area can be found in time, and the risk of the normal operation of equipment caused by the change of the electromagnetic environment of the nuclear power plant is reduced.
Description
Technical Field
The invention relates to the technical field of electromagnetic environment early warning, in particular to an electromagnetic environment early warning system and an electromagnetic environment early warning method.
Background
The electromagnetic environment of instrument control equipment in the working operation stage of a nuclear power plant is very complex, the spatial layout of units such as a power supply, equipment, cables and sensors in an instrument control equipment room is complex and changeable, the interconnection relationship among the equipment is very different, and the instrument control equipment faces numerous problems such as various electromagnetic signal forms and varieties. When the instrument control device receives a normal function signal, the instrument control device is affected by communication of other surrounding devices, voltage change, current change, power change, natural electromagnetic environment, electronic interference and other different types of signals through conduction or radiation modes, so that the function and performance of the instrument control device are affected to different degrees, and the condition of function degradation or abnormal operation occurs.
The electromagnetic environment of the nuclear power plant is complex and changeable, the electromagnetic compatibility state of the nuclear power plant in the whole service life is difficult to predict accurately and effectively in the design stage, and the application of various advanced devices and systems, wireless devices and the like introduced in the improvement of the operation stage can bring new electromagnetic interference to the nuclear power plant. Therefore, it is necessary to develop a real-time electromagnetic environment measurement system to measure and monitor the real-time electromagnetic environment of various newly built, under-construction and in-service nuclear power plants during the development lifetime, so as to integrate and form a complete set of electromagnetic compatibility management or restriction mechanism of the nuclear power plant on the basis.
At present, researches related to the electromagnetic environment of a nuclear power plant are few, a system for comprehensive perception testing of the electromagnetic environment of the nuclear power plant is not available in the industry, and an integrated, multi-parameter and high-speed comprehensive perception testing tool for the electromagnetic environment of the nuclear power plant is absent in large-scale industrial fields with various rooms, complex equipment types, wide spatial distribution, unknown electromagnetic environment risks and complex and variable types of the nuclear power plant and various testing scenes of electromagnetic signal types.
Disclosure of Invention
The invention aims to overcome the defects of the prior art, and provides an electromagnetic environment early warning system and an electromagnetic environment early warning method for the comprehensive sensing of the electromagnetic environment of a nuclear power plant, which can find electromagnetic risks in a plant area in time, find electromagnetic risks in time and process the electromagnetic risks, and fully reduce the risks brought by the electromagnetic environment change of the nuclear power plant to the normal operation of equipment.
The purpose of the invention is realized by the following technical scheme: an electromagnetic environment early warning system comprises a frequency domain measurement subsystem, a time domain measurement subsystem and a measurement and control server;
the frequency domain measurement subsystem comprises a real-time frequency spectrograph, a radio frequency matrix switch, a far field measurement module for measuring far field electromagnetic signals, a near field measurement module for measuring near field electromagnetic signals and a conduction measurement module for measuring conduction electromagnetic signals; the output ends of the far-field measuring module, the near-field measuring module and the conduction measuring module are all connected with a radio frequency matrix switch, the output end of the radio frequency matrix switch is connected with a real-time frequency spectrograph, and the real-time frequency spectrograph is used for receiving frequency domain electromagnetic signals output by the radio frequency matrix switch, completing measurement and analysis of the frequency domain electromagnetic signals and transmitting analysis results of the frequency domain electromagnetic signals to a measurement and control server;
the time domain measurement subsystem comprises an oscilloscope and a voltage probe module, wherein the voltage probe module is used for sensing and measuring the fluctuation state of a voltage signal in a cable of target equipment and transmitting the voltage signal to the oscilloscope, the oscilloscope is used for measuring and analyzing a time domain electromagnetic signal, and an analysis result of the time domain electromagnetic signal is transmitted to the measurement and control server;
the measurement and control server is integrated with a measurement and control software platform of the electromagnetic environment early warning system, and is used for receiving data transmitted by the real-time frequency spectrograph and the oscilloscope, analyzing the data and giving an alarm prompt according to a data analysis result and a preset alarm mechanism.
Furthermore, the measurement and control server is also used for controlling the operation of each device in the electromagnetic environment early warning system through a measurement and control software platform, and performing hardware parameter management, data storage, alarm mechanism management and electromagnetic environment management of the nuclear power plant in the electromagnetic environment early warning system.
Further, the far-field measurement module comprises a plurality of far-field measurement units;
each far field measuring unit comprises an ultra wide band planar antenna of 1 MHz-18 GHz, the ultra wide band planar antenna is arranged at the top of a room of a nuclear power plant, above an entrance and an exit or on the side surface of a cabinet of the nuclear power plant and is used for completing space electric field measurement in an ultra wide frequency range of 1 MHz-18 GHz and transmitting a measuring result to the radio frequency matrix switch.
Furthermore, the near field measurement module comprises a plurality of ultra wide band near field electric field probes of 10 kHz-18 GHz and a plurality of ultra wide band near field magnetic field probes of 10 kHz-18 GHz, and the output ends of the ultra wide band near field electric field probes and the ultra wide band near field magnetic field probes are connected with the radio frequency matrix switch;
the ultra-bandwidth near-field electric field probe is arranged inside a nuclear power plant cabinet and is used for sensing and measuring electric field signals of 10 kHz-18 GHz within a preset distance threshold range of key equipment inside the nuclear power plant cabinet;
the ultra-bandwidth near-field magnetic field probe is arranged inside a nuclear power plant cabinet and is used for sensing and measuring a 10 kHz-18 GHz magnetic field signal within a preset distance threshold range of key equipment inside the nuclear power plant cabinet;
the key equipment comprises a controller, a sensor and an actuator in the cabinet, and one or more of a cable port and a cable surface, wherein an ultra-bandwidth near-field electric field probe and an ultra-bandwidth magnetic field electric field probe are arranged around each key equipment.
Furthermore, the conduction measurement module comprises a plurality of current probes, the current probes adopt open type current probes and are used for conducting electromagnetic signal measurement on target cables to be tested, the output ends of the current probes are connected with the radio frequency matrix switch, and the target cables to be tested comprise one or more of power lines, signal lines, measurement lines and control lines of various devices in the nuclear power plant.
Further, the radio frequency matrix switch comprises a first-stage selection switch with 1 selected by N and second-stage selection switches with 1 selected by N, wherein N is more than or equal to 2, and M is more than or equal to 2;
the real-time frequency spectrograph comprises N first-stage selection switches, N second-stage selection switches and a real-time frequency spectrograph, wherein each input end of N first-stage selection switches is used for being connected with a different second-stage selection switch, and the output end of each first-stage selection switch is connected with the real-time frequency spectrograph and is used for selecting one path of signal from the outputs of the N second selection switches and transmitting the signal to the real-time frequency spectrograph; for each second selection switch, the M input ends of the second selection switch are used as input ports of signals, and the second selection switch is used for selecting one of the M input signals and transmitting the selected signal to the first selection switch.
Furthermore, in the process that the real-time frequency spectrograph receives the signals output by the radio-frequency matrix switch, when the radio-frequency matrix switch is switched, the conduction time of each channel is ensured to be longer than the time for the real-time frequency spectrograph to complete one-time full-band measurement;
the real-time frequency spectrograph is specifically used for circularly measuring and analyzing electromagnetic signals acquired by front-end probes and antennas of the far-field measuring module, the near-field measuring module and the conduction measuring module according to a set sequence, the measuring frequency bandwidth of the real-time frequency spectrograph is matched with the measuring frequency bandwidth of the front-end probes or the antennas, and an analysis result of each measuring and analyzing corresponds to the input end of the radio-frequency matrix switch and the front-end probes or the antennas respectively.
Further, the target equipment cable comprises one or more of a power line, a signal line, a measurement line and a control line of each equipment in the nuclear power plant cabinet, and the fluctuation state of the voltage signal comprises one or more of surge, impact, pulse group, oscillation wave and ringing wave;
the voltage probe module comprises a plurality of crocodile clip type voltage probes, each voltage probe is clamped and fixed on a target device cable to be tested, and the output end of each voltage probe is connected with the oscilloscope.
Furthermore, the oscilloscope comprises a plurality of input channels, each input channel corresponds to one voltage probe respectively, and is used for adjusting the test display time length and amplitude information in combination with the condition of signals measured by each voltage probe, and selecting a signal triggering form in combination with pulse or transient signal characteristics, wherein the triggering form comprises rising edge triggering and falling edge triggering;
the oscilloscope is also used for continuously displaying the abnormal signal when the measured pulse signal amplitude exceeds a set value;
the maximum measurement width and amplitude of the oscilloscope are matched with the voltage probe, the measurement bandwidth is larger than that of the voltage probe, the maximum input signal amplitude of the oscilloscope meets the requirement of the maximum output amplitude of the voltage probe, and the signal from the voltage probe is processed according to the set attenuation ratio, so that the oscilloscope can work normally.
Further, the electromagnetic environment early warning system also comprises a test cabinet;
the measurement and control server, the radio frequency matrix switch, the real-time frequency spectrograph and the oscilloscope are integrated in the test cabinet, a photoelectric receiving unit comprising a plurality of photoelectric receiving modules is integrated in the test cabinet of the early warning system, and the input ports of the radio frequency matrix switch are the same in number as the photoelectric receiving modules and are connected in one-to-one correspondence;
the testing cabinet is provided with a direct-connection measuring port communicated with each input end of the radio frequency matrix switch and used for directly inputting a testing signal; the test cabinet is also provided with a conversion measurement port communicated with each photoelectric receiving module and used for converting the test signal into an optical signal and inputting the obtained optical signal;
for each detection unit, if the distance between the detection unit and the early warning system test cabinet exceeds a set value, an electro-optical emission module is arranged in the detection unit, test information of the detection unit is converted into an optical signal through the electro-optical emission module and is input into a conversion measurement port in the early warning system test cabinet through an optical fiber, and after the optical signal enters a photoelectric receiving module through the conversion measurement port, the photoelectric receiving module converts the optical signal into an electrical signal and then transmits the electrical signal to the input end of a radio frequency matrix switch corresponding to the photoelectric receiving module;
if the distance between the detection unit and the early warning system test cabinet does not exceed a set value, the detection unit is directly connected into a direct connection measurement port of the early warning system test cabinet through a radio frequency cable and is directly transmitted to the input end of the radio frequency matrix switch through the direct connection measurement port;
the detection unit refers to any ultra wide band planar antenna, current probe, ultra wide band near field magnetic field probe or ultra wide band near field electric field probe in a far field measurement module, a near field measurement module, a conduction measurement module and a voltage probe module.
In a second aspect, the present invention further provides an electromagnetic environment early warning method, including:
measuring far-field electromagnetic signals through a far-field measuring module in a frequency domain measuring subsystem, measuring near-field electromagnetic signals through a near-field measuring module, measuring conducted electromagnetic signals through a conduction measuring module, inputting the frequency domain electromagnetic signals measured by the far-field measuring module, the near-field measuring module and the conduction measuring module into a real-time frequency spectrograph through a radio frequency matrix switch, measuring and analyzing the frequency domain electromagnetic signals through the real-time frequency spectrograph, and transmitting the analysis result of the frequency domain electromagnetic signals to a measurement and control server;
sensing and measuring the fluctuation state of a voltage signal in a cable of target equipment through a voltage probe module in the time domain measurement subsystem, measuring and analyzing the time domain electromagnetic signal by an oscilloscope, and transmitting the analysis result of the time domain electromagnetic signal to a measurement and control server;
a measurement and control software platform of the electromagnetic environment early warning system is integrated in a measurement and control server, receives data transmitted by a real-time frequency spectrograph and an oscilloscope through the measurement and control software platform, analyzes the data, and gives an alarm prompt according to a data analysis result and a preset alarm mechanism.
The invention has the beneficial effects that:
(1) The invention combines the characteristics of complex electromagnetic environment, dense equipment and narrow space of the nuclear power plant, designs the electromagnetic environment early warning system for comprehensively sensing the electromagnetic environment of the nuclear power plant in order to meet the practical requirement of laying in the nuclear power plant, and the electromagnetic environment early warning system can meet the requirements of small size, convenience in installation, capability of being used in the normal operation period of the nuclear power plant and the like. The real-time uninterrupted measurement of the electromagnetic environment of the power plant can be realized, the measurement result is stored in the data information processing system, and the electromagnetic environment field intensity distribution characteristics, the electromagnetic environment change characteristics along with time, the frequency spectrum distribution characteristics and the like of the whole power plant in different areas can be statistically summarized in the system by means of the statistics and calculation functions of the data information processing system.
(2) The invention has the real-time monitoring capability of electromagnetic environment characteristic parameters in a nuclear power plant, full-path data acquisition in a single period and the functions of electromagnetic interference analysis and positioning of abnormal signals.
(3) According to the invention, by additionally arranging the electromagnetic signal sensors such as the test probe and the antenna in the key area of the nuclear power plant, the dynamic acquisition of the electromagnetic environment of the nuclear power plant area is realized, when the electromagnetic environment change in the nuclear power plant exceeds the electromagnetic environment boundary in the normal working operation of each device, the system can make judgment and prompt in time, so that engineering technicians can find the electromagnetic risk in the plant area in time, find the electromagnetic risk in time and process the electromagnetic environment change in time, and the risk of the normal operation of the device caused by the electromagnetic environment change of the nuclear power plant is fully reduced.
Drawings
Fig. 1 is a schematic diagram of an electromagnetic environment early warning system according to an embodiment of the present invention;
fig. 2 is an architecture diagram of an electromagnetic environment early warning system according to an embodiment of the present invention;
fig. 3 is a schematic diagram of a radio frequency matrix switch according to an embodiment of the present invention;
fig. 4 is a schematic diagram of an overall structure of a built electromagnetic environment early warning system provided by an embodiment of the present invention.
Fig. 5 is a schematic flowchart of an electromagnetic environment early warning method according to a second embodiment of the present invention.
Detailed Description
In order to make the technical solutions of the present invention better understood, the present invention is further described in detail below with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments and figures described herein are merely illustrative of the invention and are not limiting of the invention.
It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the above-described drawings are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order; furthermore, the embodiments and features of the embodiments of the present invention may be arbitrarily combined with each other without conflict.
Wherein the terminology used in the embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used in the description of the invention and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.
In the following description, suffixes such as "module", "component", or "unit" used to denote elements are used only for facilitating the explanation of the present invention, and have no specific meaning in itself. Thus, "module", "component" or "unit" may be used mixedly.
In order to ensure that the nuclear power plant instrument control equipment does not influence the working state of each equipment in the plant area in the working operation stage, and the functional state of the equipment is kept to normally operate. The method combines the working electromagnetic environment and the electromagnetic immunity performance of the nuclear power plant instrument control equipment, comprehensively senses and measures different electromagnetic characteristics of each working position in a plant area, including typical working electromagnetic environments such as electromagnetic frequency, intensity, time domain, frequency domain, airspace and the like, and provides the electromagnetic environment characteristic envelope of a nuclear power plant instrument control equipment room through long-term monitoring analysis. The method has the advantages that electromagnetic emission and electromagnetic interference resistance characteristics which should be possessed by the instrument control equipment of the nuclear power plant under different electromagnetic environment states are analyzed, an electromagnetic characteristic boundary is formed, the adaptability of the instrument control equipment to the electromagnetic environment of a complex plant area is finally realized, and the development of the electromagnetic compatibility of the instrument control equipment is guaranteed.
The invention relates to a testing tool for comprehensive sensing, automatic monitoring and alarming of an electromagnetic environment. A series of distributed electromagnetic signal measurement sensors such as probes and antennas are flexibly arranged in a target test area, monitored electromagnetic signals are transmitted to corresponding signal acquisition and analysis modules through appropriate channels, time domain and frequency domain electromagnetic signals are respectively measured, and finally a data processing task is completed in a measurement and control server. The electromagnetic signals are analyzed and displayed in the measurement and control server, the time and space change conditions of the electromagnetic signals in the measured area of the nuclear power plant are obtained, the conditions are judged according to alarm limit values of various types of sensors, the electromagnetic environment visualization display analysis is completed, and finally the measurement results are stored, specifically:
as shown in fig. 1 and fig. 2, fig. 1 is a schematic diagram of a principle of an electromagnetic environment early warning system according to an embodiment of the present invention, and fig. 2 is an architecture diagram of the electromagnetic environment early warning system, where the electromagnetic environment early warning system includes a frequency domain measurement subsystem 1, a time domain measurement subsystem 2, and a measurement and control server 3;
the frequency domain measurement subsystem 1 comprises a real-time frequency spectrograph 11, a radio frequency matrix switch 12, a far field measurement module 13 for measuring far field electromagnetic signals, a near field measurement module 14 for measuring near field electromagnetic signals and a conduction measurement module 15 for measuring conduction electromagnetic signals; the output ends of the far-field measurement module 13, the near-field measurement module 14 and the conduction measurement module 15 are all connected with the radio frequency matrix switch 12, the output end of the radio frequency matrix switch 12 is connected with the real-time frequency spectrograph 11, and the real-time frequency spectrograph 11 is used for receiving the frequency domain electromagnetic signals output by the radio frequency matrix switch 12, completing the measurement and analysis of the frequency domain electromagnetic signals, and transmitting the analysis results of the frequency domain electromagnetic signals to the measurement and control server 3;
the time domain measurement subsystem 2 comprises an oscilloscope 21 and a voltage probe module 22, wherein the voltage probe module 22 is used for sensing and measuring the fluctuation state of a voltage signal in a cable of target equipment and transmitting the voltage signal to the oscilloscope 21, the oscilloscope 21 is used for measuring and analyzing the time domain electromagnetic signal and transmitting the analysis result of the time domain electromagnetic signal to the measurement and control server 3;
the measurement and control server 3 is integrated with a measurement and control software platform of the electromagnetic environment early warning system, and is used for receiving data transmitted by the real-time frequency spectrograph 11 and the oscilloscope 21, analyzing the data, and giving an alarm prompt according to a data analysis result and a preset alarm mechanism.
The measurement and control server 3 is also used for controlling the operation of each device in the electromagnetic environment early warning system through a measurement and control software platform, and performing hardware parameter management, data storage, alarm mechanism management and electromagnetic environment management of a nuclear power plant in the electromagnetic environment early warning system.
The electromagnetic environment management adjusts equipment of the nuclear power plant according to the electromagnetic data analysis result and the alarm condition, for example, some equipment of the nuclear power plant is started in time intervals, the fixed position of equipment installation is changed, channel division or frequency modulation is carried out, the emission power of the equipment is reduced, or a mode of combining a plurality of pieces of equipment with low power is adopted for substitution. Thereby reducing the electromagnetic risk of the electromagnetic environment of the nuclear power plant.
In the embodiment of the invention, the measurement and control server 3, the radio frequency matrix switch 12, the real-time frequency spectrograph 11 and the oscilloscope 21 are integrated into an early warning system test cabinet (test cabinet for short);
in an embodiment of the present invention, the far-field measurement module 13 includes a plurality of far-field measurement units; each far-field measuring unit comprises an ultra-wideband planar antenna of 1 MHz-18 GHz; the ultra-wideband planar antenna is arranged at the top of a room of a nuclear power plant, above an entrance, on the side surface of a cabinet of the nuclear power plant or at other positions which do not influence the installation of other equipment and the passing of personnel, and is fixedly installed; the space electric field measuring device is used for measuring a space electric field in an ultra-wide frequency range of 1MHz to 18GHz and transmitting a measuring result to the radio frequency matrix switch 12; in the embodiment, for the ultra-wideband high-sensitivity planar antenna, space electric field measurement in an ultra-wideband frequency range of 1MHz to 18GHz can be completed by using one set of antenna, so that the requirement of ultra-wideband electromagnetic signal measurement is met, the occupied space of the antenna is saved, and the arrangement and installation modes of the planar antenna are very flexible; because the measuring antenna and the early warning system testing cabinet are distributed in different rooms, the distance is far in general, and a signal which is measured by the measuring antenna needs to be transmitted to a measuring port of the early warning system testing cabinet through the photoelectric transmission unit, but for ultra-wideband planar antennas in far-field measuring units within a set distance (for example, in a room which is closer to the early warning testing cabinet), the ultra-wideband planar antennas can also be directly connected through a radio frequency cable; in the embodiment of the application, the requirement of a nuclear power plant on the space electric field test can be combined, and the number of the high-sensitivity antennas can be flexibly adjusted. The method is characterized in that a very thick reinforced cement structure is arranged among rooms of a nuclear power plant area, a very large blocking effect is achieved on electromagnetic signals, in order to guarantee signal integrity of collected weak electromagnetic signals in a transmission process, the situation that the signals are submerged by background noise due to signal attenuation caused by long-distance transmission of cables is avoided, the transmission quality of the signals is guaranteed, when the distance exceeds a set value, test information of a detection unit is converted into optical signals through an electro-optical emission module, the optical signals are input into a conversion measurement port in a test cabinet of an early warning system through optical fibers, the optical signals are converted into electric signals through a photoelectric receiving module after entering the photoelectric receiving module through the conversion measurement port, and long-distance qualitative transmission of the antenna signals of the early warning system is completed, so that the problem of transmission of the ultra-wide band electromagnetic signals of dozens of meters or even hundreds of meters is solved, and finally, when the measurement port of the test cabinet to which the electromagnetic signals reach is realized, low attenuation and complete reappearance of the signals are achieved; in order to meet the requirement of long-distance transmission, each antenna which needs the requirement of long-distance low-loss electromagnetic signal transmission needs to be individually adapted to an optical-electrical transmission channel.
In an embodiment of the present application, the near field measurement module 14 includes a plurality of ultra wide band near field electric field probes of 10kHz to 18GHz and a plurality of near field magnetic field probes of 10kHz to 18 GHz; the output ends of the ultra-wideband near-field electric field probe and the ultra-wideband near-field magnetic field probe are connected with the radio frequency matrix switch 12;
the ultra-bandwidth near-field electric field probe is arranged in a nuclear power plant cabinet and is used for sensing and measuring 10 kHz-18 GHz electric field signals around key equipment in the nuclear power plant cabinet; the circuit board-level ultra-wideband electric field signal measurement can be completed in a narrow space without being limited by space; when the near-field probe is close to the testing cabinet, the signal can be directly transmitted to the testing cabinet through the radio frequency cable; when the near-field electric field probe and the early warning system testing cabinet are distributed in different rooms or are far away from each other, the testing signal of the near-field electric field probe can be transmitted to the measuring port of the early warning system testing cabinet through the photoelectric transmission unit. And the number of the current probes is flexibly adjusted by combining the testing requirements of the nuclear power plant on the near-field electric field, and a signal transmission channel is respectively configured for each probe.
The ultra-bandwidth near-field magnetic field probe is arranged inside a nuclear power plant cabinet and is used for sensing and measuring 10 kHz-18 GHz magnetic field signals around key equipment inside the nuclear power plant cabinet; when the near-field probe is close to the test cabinet, the signal can be directly transmitted to the test cabinet through the radio frequency cable; when the near-field magnetic field probe and the early warning system testing cabinet are distributed in different rooms or are far away from each other, the testing signal of the near-field magnetic field probe can be transmitted to the measuring port of the early warning system testing cabinet through the photoelectric transmission unit. And the number of the current probes is flexibly adjusted by combining the testing requirements of the nuclear power plant on the near-field magnetic field, and a signal transmission channel is respectively configured for each channel.
The critical equipment includes controllers, sensors, actuators within the cabinet, and one or more of cable ports, cable surfaces; arranging a super-bandwidth near-field electric field probe and a super-bandwidth magnetic field electric field probe around each key device; the surrounding of the key equipment means that the distance between the key equipment and the key equipment does not exceed a preset distance threshold. The preset distance threshold may be set according to actual conditions, such as signal strength, field noise strength, and the like, and is not limited herein.
In the embodiment of the present application, the conduction measurement module 15 includes a plurality of current probes, where the current probes are open-ended current probes, and are used to measure the conduction electromagnetic signals of the target cable to be tested, and the output ends of the current probes are connected to the radio frequency matrix switch 12; the target cable to be tested comprises one or more of power lines, signal lines, measuring lines and control lines of various devices in the nuclear power plant. Electromagnetic signals are conducted, emitted and sensed, and the testing frequency ranges from thousands of hertz to hundreds of megahertz. When the distance between the current probe and the test cabinet is short, the signal can be directly transmitted to the test cabinet through the radio frequency cable; when the current probe and the test cabinet are distributed in different rooms or are far away from each other, the test signal of the current probe can be transmitted to the measurement port of the test cabinet through the photoelectric transmission unit. And the model and the quantity of the current probe are adjusted according to actual requirements of a test point position, the outer diameter of a cable, test frequency and the like by combining with the actual situation of a nuclear power plant, and a signal transmission channel is respectively configured for each channel, so that flexible arrangement is realized.
In the embodiment of the present application, the radio frequency matrix switch 12 includes a first stage selection switch of N-to-1 and N second stage selection switches of M-to-1; n is more than or equal to 2, M is more than or equal to 2, and the number is determined according to the number of the detection units.
Each input end of the N input ends of the first-stage selection switch is used for connecting a different second-stage selection switch, and the output end of the first-stage selection switch is connected with the real-time frequency spectrograph 11 and used for selecting one path of signal from the outputs of the N second selection switches to transmit to the real-time frequency spectrograph 11; for each second selection switch, the M input ends of the second selection switch are used as input ports of signals, and the second selection switch is used for selecting one path of the input M paths of signals and transmitting the selected path of signals to the first selection switch.
For the radio frequency matrix switch 12, in order to meet the requirement of the early warning system on the measurement of multiple paths of electromagnetic signals, reduce the number of the real-time frequency spectrometers 11 in the system, reduce the manufacturing cost of the early warning system, replace manual switching to improve the testing efficiency, according to the measurement control logic sequence of the early warning system, the cyclic switching and transmission of the multiple paths of electromagnetic signals are completed through the radio frequency matrix switch 12, and the electromagnetic signals of the channel to be tested are sequentially input into the radio frequency input port of the real-time frequency spectrometers 11. In the radio frequency matrix switch 12 of the present invention, the number of modules is appropriately selected according to the number of electromagnetic signal sensors such as probes and antennas through the modular multi-input single-output radio frequency switch module, in this embodiment, seven or six modules are taken as an example, wherein six modules are connected in parallel as a first-stage module, and then connected in series with a seventh module, so as to finally form a scheme of 36-channel input and 1-channel output, as shown in fig. 3, the modules are cascaded in a series-parallel manner, so as to finally realize large-scale signal input and single-channel output control, so that selective input and output of radio frequency signals are quickly realized in a test process. Finally, the radio frequency electromagnetic signal sensors such as the ultra-wideband high-sensitivity planar antenna, the high-sensitivity near-field electric field probe, the high-sensitivity near-field magnetic field probe, the current probe and the like are numbered and connected with the radio frequency input port of the radio frequency matrix switch 12 below, and the output end of the radio frequency electromagnetic signal sensor is connected with the radio frequency input port of the real-time frequency spectrograph 11.
In the embodiment of the present application, the real-time spectrometer 11 is configured to receive a signal output by the radio frequency matrix switch 12, and complete measurement and analysis of a frequency domain electromagnetic signal; when the radio frequency matrix switch 12 is switched, it is ensured that the conduction time of each channel should be at least longer than the time when the real-time frequency spectrograph 11 completes one full-frequency-band measurement; according to a set sequence, the real-time frequency spectrograph 11 circularly measures and analyzes electromagnetic signals acquired by each front-end probe and each antenna; the measuring frequency bandwidth of the real-time frequency spectrograph 11 is matched with the measuring frequency bandwidth of the front-end probe or antenna, each time of measuring data corresponds to the input end of the radio frequency matrix switch 12 and the front-end probe or antenna respectively, and finally the measuring data is sent to the measurement and control server 3.
In an embodiment of the application, a target device cable for voltage probe testing includes a combination of one or more of a power line, a signal line, a measurement line and a control line of each device in a nuclear power plant cabinet, and a fluctuation state of a voltage signal includes one or more of surge, impact, pulse group, oscillation wave and ringing wave; the test frequencies range from several hertz to hundreds of megahertz. And the model and the quantity of the voltage probes are adjusted according to actual requirements of test point positions, test frequency, voltage grades and the like by combining with the actual situation of the nuclear power plant, and signal transmission channels are respectively configured for each channel, so that flexible arrangement is realized.
The voltage probe module 22 includes a plurality of alligator clip type voltage probes, each of the voltage probes is fixed on a target device cable to be tested in a clamping manner, and an output end of the voltage probe is connected with the oscilloscope 21.
The oscilloscope 21 comprises a plurality of input channels, wherein each input channel corresponds to one voltage probe respectively and is used for adjusting the time length and amplitude information of test display in combination with the condition of signals measured by each probe and selecting a signal trigger form in combination with pulse or transient signal characteristics, and the trigger form comprises rising edge trigger and falling edge trigger; when the measured pulse signal amplitude exceeds a set value, the oscilloscope continuously displays 21 abnormal signals; the maximum measurement width and amplitude of the oscilloscope 21 are matched with the voltage probe, the measurement bandwidth is larger than the bandwidth of the voltage probe, the maximum input signal amplitude of the oscilloscope meets the requirement of the maximum output amplitude of the voltage probe, and the signal from the voltage probe is processed according to the set attenuation ratio, so that the oscilloscope 21 is ensured to work normally, and the oscilloscope 21 is not damaged due to transient pulse; the oscilloscope 21 sends the data after the test to the measurement and control server 3 through the network cable.
In the embodiment of the application, a photoelectric receiving unit comprising a plurality of photoelectric receiving modules, a display screen, a keyboard and a mouse and a plurality of reserved positions are integrated in an early warning system testing cabinet; the electro-optical transmitting module adopts an electro-optical converter, and the electro-optical receiving module adopts a photoelectric converter; as shown in fig. 4, the nuclear power plant electromagnetic environment early warning system is constructed and formed according to the invention, so that respective testing and comprehensive sensing of nuclear power plant electromagnetic environment data can be realized, measurement of multi-scene radiation and conduction electromagnetic signals of a nuclear power industrial field can be realized, sensing analysis of electromagnetic data is realized, electromagnetic element extraction is finally realized, comprehensive sensing of electromagnetic environment of each region of a whole life cycle of the nuclear power plant is realized, and the purposes of respective testing and comprehensive sensing of electromagnetic state characteristics of the nuclear power plant are achieved. The electromagnetic data analysis and processing layer has a human-computer interface interaction function, data can be automatically acquired, recorded and monitored, remote management of the sensor is completed, and functions of electromagnetic environment diagnosis and evaluation, electromagnetic environment parameter visualization and the like are finally realized.
The electromagnetic environment early warning system provided by the embodiment of the invention can adapt to the characteristics of complex electromagnetic environment, dense equipment and narrow space of a nuclear power plant, has small volume, is convenient to install and can be used in the normal operation period of the nuclear power plant. The system can realize real-time uninterrupted measurement of the electromagnetic environment of the power plant, the measurement result is stored in the data information processing system, and the electromagnetic environment field intensity distribution characteristics, the electromagnetic environment change characteristics along with time, the frequency spectrum distribution characteristics and the like of the whole power plant in different areas can be counted and summarized in the system by means of the counting and calculating functions of the data information processing system. And can realize the whole way data acquisition in the monocycle, possess the electromagnetic interference analysis and the locate function of abnormal signal. When the electromagnetic environment change in the nuclear power plant exceeds the electromagnetic environment boundary in the normal working operation of each equipment, the system can make judgment and prompt in time, ensure that engineering technicians can discover the electromagnetic risk in a plant area in time, discover and handle in time, and fully reduce the risk brought to the normal operation of the equipment by the electromagnetic environment change of the nuclear power plant.
Fig. 5 is a schematic diagram of an electromagnetic environment early warning method according to a second embodiment of the present invention, as shown in fig. 5, the method includes:
step S101: measuring far-field electromagnetic signals through a far-field measuring module in a frequency domain measuring subsystem, measuring near-field electromagnetic signals through a near-field measuring module, measuring conducted electromagnetic signals through a conduction measuring module, inputting the frequency domain electromagnetic signals measured by the far-field measuring module, the near-field measuring module and the conduction measuring module into a real-time frequency spectrograph through a radio frequency matrix switch, measuring and analyzing the frequency domain electromagnetic signals through the real-time frequency spectrograph, and transmitting the analysis result of the frequency domain electromagnetic signals to a measurement and control server;
step S102: sensing and measuring the fluctuation state of a voltage signal in a cable of target equipment by a voltage probe module in a time domain measurement subsystem, measuring and analyzing the time domain electromagnetic signal by an oscilloscope, and transmitting the analysis result of the time domain electromagnetic signal to a measurement and control server;
step S103: and a measurement and control software platform of the electromagnetic environment early warning system is integrated in the measurement and control server, receives data transmitted by the real-time frequency spectrograph and the oscilloscope through the measurement and control software platform, analyzes the data, and gives an alarm prompt according to a data analysis result and a preset alarm mechanism.
Further, the method further comprises:
the operation of each device in the electromagnetic environment early warning system is controlled through the measurement and control software platform, and hardware parameter management, data storage, alarm mechanism management and electromagnetic environment management of the nuclear power plant in the electromagnetic environment early warning system are carried out.
The electromagnetic environment early warning method of the embodiment of the disclosure is applied to the electromagnetic environment early warning system of any one of the embodiments, so the description is simpler, and reference may be made to the related description in the first embodiment of the method, which is not described herein again.
The foregoing is a preferred embodiment of the present invention, it is to be understood that the invention is not limited to the form disclosed herein, but is not to be construed as excluding other embodiments, and is capable of other combinations, modifications, and environments and is capable of changes within the scope of the inventive concept as expressed herein, commensurate with the above teachings, or the skill or knowledge of the relevant art. And that modifications and variations may be effected by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (11)
1. An electromagnetic environment early warning system is characterized by comprising a frequency domain measurement subsystem, a time domain measurement subsystem and a measurement and control server;
the frequency domain measurement subsystem comprises a real-time frequency spectrograph, a radio frequency matrix switch, a far field measurement module for measuring far field electromagnetic signals, a near field measurement module for measuring near field electromagnetic signals and a conduction measurement module for measuring conduction electromagnetic signals; the output ends of the far-field measuring module, the near-field measuring module and the conduction measuring module are all connected with a radio frequency matrix switch, the output end of the radio frequency matrix switch is connected with a real-time frequency spectrograph, and the real-time frequency spectrograph is used for receiving frequency domain electromagnetic signals output by the radio frequency matrix switch, completing measurement and analysis of the frequency domain electromagnetic signals, and transmitting analysis results of the frequency domain electromagnetic signals to a measurement and control server;
the time domain measurement subsystem comprises an oscilloscope and a voltage probe module, wherein the voltage probe module is used for sensing and measuring the fluctuation state of a voltage signal in a cable of target equipment and transmitting the voltage signal to the oscilloscope, the oscilloscope is used for measuring and analyzing a time domain electromagnetic signal, and an analysis result of the time domain electromagnetic signal is transmitted to the measurement and control server;
the measurement and control server is integrated with a measurement and control software platform of the electromagnetic environment early warning system, and is used for receiving data transmitted by the real-time frequency spectrograph and the oscilloscope, analyzing the data and giving an alarm prompt according to a data analysis result and a preset alarm mechanism.
2. The electromagnetic environment early warning system of claim 1, wherein the measurement and control server is further configured to control operations of devices in the electromagnetic environment early warning system through a measurement and control software platform, and perform hardware parameter management, data storage, alarm mechanism management and electromagnetic environment management of the nuclear power plant in the electromagnetic environment early warning system.
3. The electromagnetic environment early warning system of claim 1, wherein the far-field measurement module comprises a plurality of far-field measurement units;
each far field measuring unit comprises an ultra wide band planar antenna of 1 MHz-18 GHz, the ultra wide band planar antenna is arranged at the top of a room of a nuclear power plant, above an entrance and an exit or on the side surface of a cabinet of the nuclear power plant and is used for completing space electric field measurement in an ultra wide frequency range of 1 MHz-18 GHz and transmitting a measuring result to the radio frequency matrix switch.
4. The electromagnetic environment early warning system of claim 1, wherein the near field measurement module comprises a plurality of ultra wide band near field electric field probes of 10kHz to 18GHz and a plurality of ultra wide band near field magnetic field probes of 10kHz to 18GHz, and the output ends of the ultra wide band near field electric field probes and the ultra wide band near field magnetic field probes are connected to the radio frequency matrix switch;
the ultra-bandwidth near-field electric field probe is arranged inside a nuclear power plant cabinet and is used for sensing and measuring electric field signals of 10 kHz-18 GHz within a preset distance threshold range of key equipment inside the nuclear power plant cabinet;
the ultra-bandwidth near-field magnetic field probe is arranged inside a nuclear power plant cabinet and is used for sensing and measuring a 10 kHz-18 GHz magnetic field signal within a preset distance threshold range of key equipment inside the nuclear power plant cabinet;
the key equipment comprises a controller, a sensor and an actuator in the cabinet, and one or more of a cable port and a cable surface, wherein an ultra-bandwidth near-field electric field probe and an ultra-bandwidth magnetic field electric field probe are arranged around each key equipment.
5. The electromagnetic environment early warning system of claim 1, wherein the conduction measurement module comprises a plurality of current probes, the current probes are open-type current probes and are used for conducting electromagnetic signal measurement on a target cable to be tested, and output ends of the current probes are connected with the radio frequency matrix switch; the target cable to be tested comprises one or more of power lines, signal lines, measuring lines and control lines of various devices in the nuclear power plant.
6. The electromagnetic environment early warning system of claim 1, wherein the radio frequency matrix switch comprises a first stage selection switch of 1 from N and a second stage selection switch of 1 from M, wherein N is greater than or equal to 2, and M is greater than or equal to 2;
the real-time spectrum analyzer comprises N input ends of a first-stage selection switch, a real-time spectrum analyzer and N second-stage selection switches, wherein each input end of the N input ends of the first-stage selection switch is used for being connected with one different second-stage selection switch, and the output end of the first-stage selection switch is connected with the real-time spectrum analyzer and used for selecting one path of signals from the outputs of the N second-stage selection switches and transmitting the signals to the real-time spectrum analyzer; for each second selection switch, the M input ends of the second selection switch are used as input ports of signals, and the second selection switch is used for selecting one path of the input M paths of signals and transmitting the selected path of signals to the first selection switch.
7. The electromagnetic environment early warning system of claim 6, wherein in the process of the real-time spectrometer receiving the signal output by the radio frequency matrix switch, when the radio frequency matrix switch is switched, the on-time of each channel is ensured to be longer than the time for the real-time spectrometer to complete one full-band measurement;
the real-time frequency spectrograph is specifically used for circularly measuring and analyzing electromagnetic signals acquired by front-end probes and antennas of the far-field measuring module, the near-field measuring module and the conduction measuring module according to a set sequence, the measuring frequency bandwidth of the real-time frequency spectrograph is matched with the measuring frequency bandwidth of the front-end probes or the antennas, and an analysis result of each measurement and analysis corresponds to the input end of the radio-frequency matrix switch and the front-end probes or the antennas respectively.
8. The electromagnetic environment early warning system of claim 1, wherein the target equipment cable comprises a combination of one or more of a power line, a signal line, a measurement line, and a control line of each equipment in a nuclear power plant cabinet, and the fluctuation state of the voltage signal comprises one or more of surge, shock, pulse group, oscillatory wave, and ringing wave;
the voltage probe module comprises a plurality of crocodile clip type voltage probes, each voltage probe is clamped and fixed on a target device cable to be tested, and the output end of each voltage probe is connected with the oscilloscope.
9. The electromagnetic environment early warning system of claim 8, wherein the oscilloscope comprises a plurality of input channels, each input channel corresponds to one voltage probe, and is used for adjusting the test display time length and amplitude information in combination with the condition of the signal measured by each voltage probe, and selecting a signal trigger form in combination with pulse or transient signal characteristics, wherein the trigger form comprises rising edge trigger and falling edge trigger;
the oscilloscope is also used for continuously displaying the abnormal signal when the measured pulse signal amplitude exceeds a set value;
the maximum measurement width and amplitude of the oscilloscope are matched with the voltage probe, the measurement bandwidth is larger than that of the voltage probe, the maximum input signal amplitude of the oscilloscope meets the requirement of the maximum output amplitude of the voltage probe, and the signal from the voltage probe is processed according to the set attenuation ratio, so that the oscilloscope can work normally.
10. The electromagnetic environment warning system of any one of claims 1 to 9, further comprising a test cabinet;
the measurement and control server, the radio frequency matrix switch, the real-time frequency spectrograph and the oscilloscope are integrated in the test cabinet, a photoelectric receiving unit comprising a plurality of photoelectric receiving modules is integrated in the test cabinet of the early warning system, and the input ports of the radio frequency matrix switch are the same in number as the photoelectric receiving modules and are connected in one-to-one correspondence;
the test cabinet is provided with a direct connection measurement port communicated with each input end of the radio frequency matrix switch and used for directly inputting a test signal; the test cabinet is also provided with a conversion measurement port communicated with each photoelectric receiving module and used for converting the test signal into an optical signal and inputting the obtained optical signal;
for each detection unit, if the distance between the detection unit and the early warning system test cabinet exceeds a set value, an electro-optical emission module is arranged in the detection unit, test information of the detection unit is converted into an optical signal through the electro-optical emission module and is input into a conversion measurement port in the early warning system test cabinet through an optical fiber, and after the optical signal enters a photoelectric receiving module through the conversion measurement port, the photoelectric receiving module converts the optical signal into an electrical signal and then transmits the electrical signal to the input end of a radio frequency matrix switch corresponding to the photoelectric receiving module;
if the distance between the detection unit and the early warning system test cabinet does not exceed a set value, the detection unit is directly connected into a direct connection measurement port of the early warning system test cabinet through a radio frequency cable and is directly transmitted to the input end of the radio frequency matrix switch through the direct connection measurement port;
the detection unit refers to any ultra wide band planar antenna, current probe, ultra wide band near field magnetic field probe or ultra wide band near field electric field probe in a far field measurement module, a near field measurement module, a conduction measurement module and a voltage probe module.
11. An electromagnetic environment early warning method, characterized in that the method comprises:
measuring far-field electromagnetic signals through a far-field measuring module in a frequency domain measuring subsystem, measuring near-field electromagnetic signals through a near-field measuring module, measuring conducted electromagnetic signals through a conduction measuring module, inputting the frequency domain electromagnetic signals measured by the far-field measuring module, the near-field measuring module and the conduction measuring module into a real-time frequency spectrograph through a radio frequency matrix switch, measuring and analyzing the frequency domain electromagnetic signals through the real-time frequency spectrograph, and transmitting the analysis result of the frequency domain electromagnetic signals to a measurement and control server;
sensing and measuring the fluctuation state of a voltage signal in a cable of target equipment through a voltage probe module in the time domain measurement subsystem, measuring and analyzing the time domain electromagnetic signal by an oscilloscope, and transmitting the analysis result of the time domain electromagnetic signal to a measurement and control server;
and a measurement and control software platform of the electromagnetic environment early warning system is integrated in the measurement and control server, receives data transmitted by the real-time frequency spectrograph and the oscilloscope through the measurement and control software platform, analyzes the data, and gives an alarm prompt according to a data analysis result and a preset alarm mechanism.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115993488A (en) * | 2023-03-24 | 2023-04-21 | 天津安力信通讯科技有限公司 | Intelligent monitoring method and system for electromagnetic environment |
| CN117825847A (en) * | 2024-01-02 | 2024-04-05 | 北京航空航天大学 | Device and method for testing shielding performance of multi-conductor cable based on reverberation room |
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2022
- 2022-11-21 CN CN202211454043.8A patent/CN115792407A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115993488A (en) * | 2023-03-24 | 2023-04-21 | 天津安力信通讯科技有限公司 | Intelligent monitoring method and system for electromagnetic environment |
| CN117825847A (en) * | 2024-01-02 | 2024-04-05 | 北京航空航天大学 | Device and method for testing shielding performance of multi-conductor cable based on reverberation room |
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