88results about How to "Long monitoring distance" patented technology

The invention relates to an automatic monitoring method and system for long distance pipeline safety. It uses the monomode optical fiber laid near the distant pipeline, or the backup monomode optical fiber in the measured cable as sensing element; when the pipeline has leakage or the pipeline is damaged, the transmission character of the optical fiber will be changed, the light path difference of the laser in the two fibers will be changed; the change can be acquired with light interference method; at the same time, uses the affection of exterior force to the monomode optical fiber, and locating the position of the exterior on the pipeline. The several monitoring systems can be assembled into a network, thus the high sensitive, remote, real-time and automatic monitor to the long distance pipeline can be realized.

The invention relates to a fiber distributed monitoring method and device for the safety monitoring of a long-distance pipeline. By using a fiber Sagner interferometer fiber consisting of a laser, a 2 is multiplied by 2 coupler and two optical fibers arranged in parallel to the long-distance pipeline, the invasion or leakage events are detected based on the interference signal caused by oscillation phenomenon. An optical fiber delay line is preset at the emergence end of either of the two optical fibers under the condition that the two optical fibers oscillate at the same time. An optical fiber delay line is preset at the farthest end under the condition that either of the two optical fibers oscillates. The interference factor is compensated by means of periodic narrow pulses, record light source fluctuation and equilibrium demodulation, thereby realizing the long-distance pipeline safety detection with high sensitivity. The invention also uses a computer database to store and sort data, analyze the event type and give alarms of different levels. The invention utilizes low-cost mobile modules to combine a plurality of independent devices distributed along the long-distance pipeline and thus to form the long-distance wireless monitoring system, and realizes the roll call measurement, periodic measurement and data upload.

The invention relates to a high-magnifying long-focus zooming camera lens which is characterized in that an optical path structure is respectively provided with a front fixed group with positive focal power, a zooming group with negative focal power, a compensation group with negative focal power and a rear fixed group with negative focal power along the incident light in the direction from the left to the right; the front fixed group is provided with a double-convex lens and a gluing group separated from the double-convex lens in sequence; the zooming group is provided with a negative meniscus lens and a gluing group separated from the negative meniscus lens in sequence; the compensation group is provided with a negative meniscus lens gluing group and a positive meniscus lens gluing group which are mutually glued; and the front part of the rear fixed group is provided with the double-convex lens and a positive meniscus lens separated from the double-convex lens, the middle part thereof is provided with the gluing group and the positive meniscus lens in sequence and the rear part thereof is provided with a meniscus lens and the double-convex lens separated from the meniscus lens. The high-magnifying long-focus zooming camera lens can improve the optical zoom of the zoom lens, and shorten the length of the optical structure so as to being capable of being installed on a general holder, increasing optical rear intercept and improving the resolution of the lens.

The invention provides a remote optical fiber cable temperature detection alarm system and method. If it is monitored that a cable breaks down, the temperature of a fault point rises, the attenuation of an optical signal in the transmission process in a temperature-sensing optical cable is over large, and finally the optical power of received light collected at the optical signal output end of the temperature-sensing optical cable drops abnormally and substantially; whether the monitored cable breaks down or not is judged by monitoring data of the optical power of emitted light and data of the optical power of the received light. By means of the remote optical fiber cable temperature detection alarm system and method, the technical requirement for a laser device, light-sensing signals and signal processing is low, later maintenance technology is simple, the effective life is long, the monitoring distance is long, the cost is low, and popularization and use are facilitated.

The invention discloses a distributed optical fiber equal salt deposit density sensor and a sensing method thereof. The distributed optical fiber equal salt deposit density sensor comprises a light transmitting unit, a light modulating unit, a light receiving unit and a signal processing unit; integral information of the equal salt deposit density strength in areas where sensing optical fibers pass can be obtained by using the distributed optical fiber equal salt deposit density sensor according to the invention to perform one measurement, and the sensor has long system monitor range and high positioning accuracy. Simultaneously, the invention further provides a sensing method of the distributed optical fiber equal salt deposit density sensor, which includes simple steps and can conveniently measure the distribution information of the equal salt deposit density strength in target areas.

The invention discloses a method for detecting an iced and damaged transmission line and relates to a device for realizing the method. The method comprises the steps of: (1) arranging an elastic wave exciting element and an elastic wave sensing element on a fine transmission line and generating a fine signal, (2) amplifying the fine signal obtained from the step (1) and storing as a reference signal, (3) for monitoring, exciting the elastic wave exciting element and receiving a monitored signal and storing through the sensing element, (4) comparing the signals from the step (1) and step (3), judging the difference between the two signals so as to judge if the line is damaged, and (5) if being damaged, analyzing and comparing the difference between the signals from the step (1) and step (3), therefore positioning and identifying the damage. The method of the invention which can completely replace the traditional monitoring method is characterized by long monitoring distance, high monitoring efficiency, simple and easily operated equipment and high safety and can be applied to similar lines. The device of the invention has simple structure and operation.

The invention relates to a long distance concentrated sulphuric acid pipe leakage monitoring method, including that a cable and a cable fault monitor are utilized to monitor leakage state and leakage position of concentrated sulphuric acid pipe. The method is characterized in that the cable is an acid sensitive one with dressing made by polyether-ether-ketone PEEK material, adapts to water, alkali or mixture thereof and multiple mediums and is sensitive to concentrated sulphuric acid only, the acid sensitive cable is parallelly paved at the bottom of pipe along the whole course of concentrated sulphuric acid pipe, one end of the acid sensitive cable is connected on to the cable fault monitor, concentrated sulphuric acid leakage is monitored in real time, and the cable fault monitor automatically alarms once pipe leakage happens and provides the position of leakage point. The invention has the advantages that monitoring distance is long, single section longest monitoring distance can reach 30km, the method is heat resistant and can be resistant to high temperature of 250 DEG C for a long time, insulating property is good, structure is simple, use convenience is achieved, cost is low, no danger is produced, and online monitoring, leakage alarming and leakage positioning can be realized, and the invention is widely applied in long distance concentrated sulphuric acid pipe leakage monitoring.

The invention discloses a transmission line galloping monitoring method based on OPGW ground wire induced current. It is assumed that the galloping frequency, galloping amplitude and galloping position of a transmission line conductor need to be deduced by measuring the induced current on an OPGW ground wire of an N-th base tower of a transmission line. The transmission line galloping monitoring method comprises the following steps that a current transformer is installed on the OPGW ground wire of the N-th base tower, and the output end of the current transformer is connected with wave recorders; the wave recorders are provided with a trigger threshold value, and the wave recorders do not record waveforms when the line works normally; and when the conductor gallops, the OPGW ground wire iscoupled with induced overcurrent, the wave recorders are triggered and record the current waveforms; according to signal analysis and an electromagnetic field theory, the coupling coefficient betweenthe OPGW ground wire and conductor is calculated, so that the galloping frequency and galloping amplitude of the conductor are calculated; and by analyzing the waveforms recorded by the wave recorders installed on different towers, the galloping position is located.

The invention discloses an optical fiber vibration sensing system and a using method thereof based on double Mach-Zehnder interferometers. An end A machine and a end B machine of the system are arranged at two ends of the interferometer, a control module of each end machine is connected with a light source as well as a detecting collection and communication module, the end A machine is further provided with a time synchronization module. A communication fiber is connected with the communication modules of the end A machine and the end B machine. The light source module of the end A machine and the end B machine is connected with the detecting collection module of an opposite end machine through a sensing optical fiber and an optical coupler to form double interferometers. The using method of the system comprises the following steps of: setting a threshold value by the control module of the end A machine, respectively outputting the interference information of optical signals of the end A machine and the end B machine to the opposite end machine; sending a collection triggering signal by the control module of the end A machine and starting to collect data by a second end machine when the sensing optical fiber influenced by vibrating to interfere in the information reaches the threshold value; determining the position of interfering on the sensing optical fiber by the control module of the end A machine according to two-path collecting data and the time synchronization information. The invention has double light sources, low loss of optical power, longer monitoring distance and higher sensitivity.

The invention discloses a safety monitoring system based on distributed optical fiber, comprising a transmitted and received light signal processing module 100, a light delay component 101 and a loop optical fiber part 102 which are formed into a double-variant-type optical fiber Sagnac interferometer. The transmitted and received light signal processing module 1 comprises a computer 1, a light source driver 2, a light source 3, a polarization remover 4, a detector 10 and a circuit processing board 11 with a detector. The light delay component 2 comprises a 3*3 optical fiber coupler 5, a short fiber 6, a long fiber 7 and a 2*1 coupler 8. The loop optical fiber part 102 relates to induction optical fibers 9 of two cases, i.e. vibration and impact act on the two optical fibers in a loop or on one optical fiber in the loop. A single system is additionally provided with a light switch to perform multi-channel periodic route-inspection measurement and monitor large-area vibration. The remote intelligent monitoring can be realized through the networking of a plurality of monitoring systems.

The invention discloses a fire early warning system for a photovoltaic power station. The fire early warning system for a photovoltaic power station includes a plurality of temperature-sensing opticalfibers arranged in the photovoltaic power station, a plurality of temperature measuring hosts and a monitoring host, wherein the plurality of temperature-sensing optical fibers use the self-containedmeter standard device to calibrate all the monitoring points in the corresponding optical fiber, and output the optical fiber scattering signals; each temperature measuring host is connected to several temperature-sensing optical fibers to collect the fiber scattering signals output by the temperature-sensing optical fibers connected to the each temperature measuring host in the preset interval,calculate the position data, the field temperature and the temperature level of each monitoring point, and output the monitoring point temperature data set under all the monitoring points; and the monitoring host is connected with the plurality of temperature measuring hosts to monitor all the temperature measuring hosts, receive and analyze the monitoring point temperature data set, perform dataanalysis and processing on the analysis results, and output alarm information. The fire early warning system for a photovoltaic power station has the advantages of a complete fire early warning mechanism, accurate positioning of monitoring point, long monitoring distance, high flexibility, and high anti-interference ability, and all the settings are completed in the terminal, and the whole systemis simple and reliable.

The invention discloses an active infrared video camera, which comprises a light-projecting device (1) and a pick-up device (2). The light-projecting device (1) emits infrared rays to a monitored area, and the pick-up device (2) receives the image information of the monitored area. The light-projecting device (1) comprises an LED emission light source (10) and a transmitting mirror group (11) with the function of optically zooming, wherein the transmitting mirror group (11) comprises a plurality of lenses. The infrared rays emitted by the LED emission light source (10) irradiate the monitored area after passing through the transmitting mirror group (11). Therefore, the active infrared video camera (100) is more flexible and efficient, and can be more widely applied.

The invention discloses a full sensing interference-type optical time domain reflectometer. The full sensing interference-type optical time domain reflectometer comprises an optical signal emitting and receiving processing module [100] and a sensing fiber [101] and a sensing fiber [102]; the optical signal emitting and receiving processing module [100] comprises a computer [1], a light source driver [2], a light source [3], a detector [4], a circuit processing board [5] with the detector and a fiber coupler [6]; and two circuits of the sensing fiber [101] and the sensing fiber[102] form a cable and realize the long-distance distributed vibration, impact detection and positioning. A single full sensing interference-type optical time domain reflectometer is additionally provided with an optical switch for carrying out multichannel periodic check and measurement and monitoring to the phenomena of large-area vibration and impact. A plurality of reflectometers are connected to the Internet to realize remote intelligent monitoring.

The invention discloses an underground pipeline identification and monitoring system and a use method. The system comprises a pipeline instrument and a geological radar, a strain sensing optical fiber, a temperature compensation optical fiber, an optical fiber data acquisition and transmission system, an optical fiber data processing and analysis system, a monitoring result display system and a pipeline CCTV (Closed Circuit Television Inspection) detection system. A pipeline is identified through the pipeline instrument and the geological radar; real-time optical fiber acquisition and transmission are carried out through distributed sensing optical fibers outside the pipeline and the optical fiber data acquisition and transmission system, and stress, temperature and deformation of the pipeline are obtained through the optical fiber data processing system; and the pipeline CCTV detection system is used for carrying out pipeline rust layer, scaling, corrosion, perforating, crack detection and camera shooting. The underground pipeline identification and monitoring system is rapid and accurate in positioning, long in monitoring distance, comprehensive in collected data and high in sensitivity and accuracy, and rapid and accurate identification and monitoring of the underground pipeline are achieved.

The invention discloses a bridge safety monitoring method based on an optical fiber, and a monitoring mechanism thereof. The method comprises the following steps: laying a sensing optical cable alonga bridge structure direction, arranging a three-dimensional acceleration structure on the bridge, and winding the sensing optical cable on a three-dimensional acceleration structure; arranging an optical fiber displacement sensor at a connecting part of the adjacent bridge floors, and enabling the optical fiber displacement sensor to communicate and connect with a input end of the optical fiber sensor through the sensing optical cable; communicating and connecting with a coupler at an end part of the sensing optical cable, and communicating and connecting with a narrow linewidth pulse laser device and an optical fiber vibration signal demodulation system through the coupler; enabling the emitted light to enter the sensing optical cable through the coupler by the narrow linewidth pulse laser device, and enabling the reflected light returned by the sensing optical cable to enter an optical fiber vibration signal demodulation system through a coupler, wherein the optical fiber vibration signal demodulation system demodulates vibration information of the bridge, thereby assessing the safety condition of the bridge. The monitoring method disclosed by the invention is convenient to construct, simple in operation, good in monitoring effect, high in monitoring precision, wide in applicable range, and suitable for any bridge.

The invention discloses a monitoring probe with an alarm function for a dangerous river reach, and relates to the technical field of monitoring probes. The monitoring probe comprises a fixed base, a power box is welded to the top of the fixed base, and a battery pack is fixedly installed in the power box. A supporting column is arranged above the power box, and a driving motor is arranged in the supporting column. According to the monitoring probe with the alarm function for the dangerous river reach, a servo motor and an electric push rod are started, the servo motor drives a camera to rotate(transversely rotate) through a bearing, a rotating column and a connecting shaft, and the electric push rod enables the camera to rotate (vertically rotate), so that the monitoring work of the camera is conveniently completed. The monitoring mechanism is convenient to use and long in monitoring distance, the camera can carry out all-around monitoring work, when dangerous situations are monitoredin a river channel, the monitoring equipment can transmit information to a command and control center through a signal generator, in this way, rescue work can be carried out on drowning people in time, and high practical performance is achieved.

The invention discloses a distributed type sensing device based on a double-core double-wrapping layer optical fiber. The distributed type sensing device based on the double-core double-wrapping layer optical fiber comprises a controlling module, a light source module, a first light detector module and a second light detector module. The light source module, the first light detector module and the second light detector module are respectively connected with the controlling module. One opening end of a1*2 light coupler and one opening end of a 1*2 third light coupler are respectively connected with a first passage and a second passage. The first passage and the second passage are arranged in the inner portion of the light coupler and are not mutually interfered. The distributed type sensing device based on the double-core double-wrapping layer optical fiber further comprises a sensing optical fiber. The sensing optical fiber comprises a first wrapping layer and a second wrapping layer arranged on the outer side of the first wrapping layer. A first fiber core and a second fiber core are arranged in the first wrapping layer in a side-by-side mode. A protection layer is arranged on the outer side of the second wrapping layer. The first passage and the second passage are respectively connected with the first fiber core and the second fiber core of the sensing optical fiber. The distributed type sensing device based on the double-core double-wrapping layer optical fiber is convenient to use and low in cost. The distributed type sensing device based on the double-core double-wrapping layer optical fiber has good application prospect.

The invention discloses a shield tunnel surrounding rock deformation advanced monitoring structure and a monitoring method. The shield tunnel surrounding rock deformation advanced monitoring structurecomprises a monitoring main body composed of a plurality of monitoring sections, flexible connection sections and angle sensing devices arranged on the monitoring sections, and two ends of each flexible connection section are respectively connected with the head sections and the tail ends of two adjacent monitoring sections; the angle sensing devices are used for monitoring the angles between themonitoring sections on the angle sensing devices and the horizontal plane and the vertical plane. The device has the function of long-distance monitoring in the axis direction of the tunnel, deformation data of surrounding rocks with different pile numbers in the axis of the tunnel can be obtained through the multiple monitoring points of the monitoring body, and the monitoring result is more accurate.