81results about How to "Accurate online monitoring" patented technology

This invention discloses an on-line monitoring method of grounding net of power station and its device. The method includes following steps: bury state transmitter in soil where have station earthing net; survey electric resistance of transmitter electrode and self corrosion electric potential; add square wave signal to electrode of state transmitter, survey electric current; after smoothing surveyed data, deliver to microprocessor to compute corrosion rate of electrode, take it as corrosion rate of grounding electrode in corresponding area; use corrosion rate to compute corrosion deep and actual geometry size of grounding electrode of grounding net, and use computing method of grounding net numerus to compute electricity performance parameter of grounding net; compare computed electricity performance parameter and design value, judge safe performance of grounding net. This invention can do online monitoring to corrosion deep and electricity performance parameter of grounding net of power station. The invention provides a overall, effective, economic, real time solving method to survey and evaluate grounding net of power station.

The invention discloses a transformer substation patrol and inspection robot with a rod climbing function and a drive method for the transformer substation patrol and inspection robot. The transformer substation patrol and inspection robot comprises a monitoring device, a drive control module and a climbing mechanism. The monitoring device and the drive control module are arranged on the climbing mechanism. The climbing mechanism comprises multiple sections of body units and body joints. The adjacent body units are connected through the body joints. A body joint motor is arranged between every two adjacent body units. Each body unit is provided with a pair of mechanical arms. The ends of each mechanical arm are provided with walking and rotating universal wheels and universal wheel drive mechanisms. The universal wheel drive mechanisms and the body joint motors are connected with the drive control module. The drive method includes the steps that the transformer substation patrol and inspection robot is driven to move on the ground, move up and down a rod column and climb / rotate / stop along the rod column. By the adoption of the robot and the method, the functions that the robot moves on the ground, moves up and down the rod column and climbs / rotates / stops along the rod column can be achieved, the structure is compact, the control accuracy is high, and the operating state of a power transformation device can be monitored in all directions without a dead zone.

The invention discloses an ammonia nitrogen on-line monitoring system and a method thereof. The system comprises a sampling module used for obtaining a sample to be detected in a current pond; a signal detection module used for mixing the sample to be detected and a reagent NaOH solution, detecting an ammonia nitrogen concentration signal, a PH value signal and a temperature value signal of the collected water body; a signal processing module used for respectively processing the ammonia nitrogen concentration signal, the PH value signal and the temperature value signal of the collected water body detected by the signal detection module to obtain an ammonia nitrogen concentration voltage signal, a PH value voltage signal and a temperature value voltage signal; and a calculating control module used for calculating the ammonia nitrogen content in the collected water body through a data fusion algorithm according to the ammonia nitrogen concentration voltage signal, the PH value voltage signal and the temperature value voltage signal sent from the signal processing module. The apparatus has a simple structure, and can accurately and timely monitor the ammonia nitrogen content in culture water.

The present invention relates to a method for on-line measuring dirty extent of the condenser and its equipment. The equipment includes several sensors, signal conditioning circuit, multiway switch, DSP, in which all the sensors are connected with signal conditioning circuit and multiway switch, at the same time connected with DSP, the LED display, keyboard and communication interface are connected with DSP. It utilizes heat transfer terminal difference as researching object, duty parameter variation and fuzzy film-forming technology to accurately implement on-line measurement of the dirty extent of condenser.

The invention relates to an online monitoring device for a turn-to-turn insulation fault of an air-core power reactor, which is characterized by comprising a method for judging a turn-to-turn insulation fault of the air-core power reactor through changes in value of a loss factor. The online monitoring device is composed of a signal extraction portion, a signal conversion control portion, a computer operation portion and a display and alarm portion, and is characterized in that terminal voltage and current signals of a monitored reactor are extracted by applying a voltage transformer and a current transformer, the terminal voltage and current signals are zoomed so as to conform to a processing range of an AD converter, a single-chip microcomputer controls the AD converter to perform processing on analog voltage and current signals, the processed analog voltage and current signals are sent to a computer to perform analysis and calculation on a loss factor, active power and reactive power are calculated through current and voltage signals, and the loss factor is calculated; changes of the loss factor tan<delta> is monitored online in real time, the loss factor tan<delta> is compared with a loss factor tan<delta> threshold under normal power reactor running, a running state of the reactor is displayed, and an alarm is given out when the loss factor tan<delta> exceeds the threshold. The online monitoring device realizes online monitoring for the air-core power reactor; a detection objective is realized via the proposed method of being according to changes of the loss factor, thereby promoting and expanding a new direction of online monitoring for the air-core power reactor; and the running reliability of the air-core power reactor is improved.

The invention provides an on-line monitoring device for a high-voltage circuit breaker. The on-line monitoring device comprises a sensor module and an on-line high-voltage circuit breaker monitoring unit, wherein the on-line high-voltage circuit breaker monitoring unit comprises a single-chip microcomputer module, a communication module, a human-machine interaction module and an alarming module; the single-chip microcomputer module is a functional module and is integrated with a data amplification module, a filtering module, an A / D (analog / digital) conversion module, a micro processor module, a fault diagnosis module and an interface module. The on-line monitoring device for the high-voltage circuit breaker performs real-time monitoring according to switch on and switch off current of the circuit breaker and state information such as a travel mechanical characteristic of a main contact, so that the definite state information can be supplied in real time, and local digitalization, remote networking and monitoring and prewarning automation are realized; therefore the reliability of running of the circuit breaker is improved. The device can comprehensively, scientifically and accurately monitor a real-time running state of the high-voltage circuit breaker on line, effectively avoid strong electromagnetic interference and completely and safely send data to a monitoring terminal.

The invention discloses a dirty factor detection device for a condenser. The dirty factor detection device comprises an industrial personal computer, wherein a temperature sensor, a pressure sensor, a flowmeter and an upper computer are connected on the industrial personal computer, and the temperature sensor, the pressure sensor and the flowmeter are respectively connected with the industrial personal computer through an A / D (analog / digital) conversion module. According to the dirty factor detection device disclosed by the invention, the problem of difficult measurement of a dirty factor of the condenser in the prior art is solved, more accurate online monitoring of the dirty factor of the condenser can be realized by collecting related parameters in all the positions of the condenser and inputting the collected parameters to the upper computer for calculation, and data support can be provided for late-stage cleaning of the condenser.

A wind-electricity draught fan blade crack damage online monitoring device includes a piezoelectric thin film sensor module, a wireless signal receiving module, a data processing module, and a main control system communication module; the piezoelectric thin film sensor module is arranged on wind-electricity draught fan blades and is electrically connected with a charge amplifying module, an A / D conversion module and a wireless transmitting module; the wireless signal receiving module is used for receiving a signal collected by the piezoelectric thin film sensor module and outputted by the wireless transmitting module; the data processing module is used for processing the signal received by the wireless signal receiving module, so as to on-line monitoring whether crack damage of the wind-electricity draught fan blades exists or not; the main control system communication module is electrically connected with the data processing module and is used for controlling operation of the wind-electricity draught fan blades. A natural vibration frequency band is used for determining the damage, the influence of environmental changes and vibration of draught fan self parts is reduced, the monitoring accuracy is improved, and the device is more adaptive and can quickly accurately perform on-line real-time monitoring of the crack damage of the wind-electricity draught fan blades.

The invention discloses a method for online monitoring the vacuum degree of an arc extinguishing chamber of a vacuum switch of an intelligent switch cabinet. The method comprises a shielding case potential method and a magnet-controlled discharge method which are used together, wherein the shielding case potential method is used for continuously monitoring the vacuum degree of the three-phase arc extinguishing chamber of the vacuum switch; and the magnet-controlled discharge method is used for discontinuously monitoring the vacuum degree of the three-phase arc extinguishing chamber in turn. By the technical scheme provided by the invention, the vacuum degree of the arc extinguishing chamber can be online detected reliably, accurately and continuously without performing any reformation on the arc extinguishing chamber of the vacuum switch; and the method is widely applicable.

The on-line monitor method to the conductivity in beer fermentation process comprises, using the relation between conductivity and reducing sugar, alpha-amino nitrogen or alcohol degree to build opposite mathematic model; checking the real process and standard curve to realize detection to other parameters indirectly and monitor fermentation process. This method is rapid, synchronous and precise.

The invention discloses an optical wave-based transmission line equivalent salt deposit density sensor which comprises a hollow shell, wherein a monitoring device board is arranged in the hollow shell and comprises a microcontroller; a laser transmitting module, a laser receiving module, a communication module, a data storage module, a power module and a temperature and humidity acquisition module are respectively connected to the microcontroller; the temperature and humidity acquisition module stretches out of the hollow shell. The invention also discloses a method for measuring salt density on line. The wide distribution theory and light energy loss mechanism in dielectric optical waveguide are utilized, the optical power attenuation, environment temperature, relative humidity and other data of the optical sensor are measured, the insulator equivalent salt deposit density with high accuracy is deduced by utilizing an established neural network model, pollution of a field insulator on the transmission line can be accurately monitored in real time or timely on line, the pollution on the transmission line caused by the insulator is globally diagnosed and monitored, and early warning information is provided.

The invention relates to an online monitoring method for the scaling thickness on the surface of an electric heating element of an electric boiler, which is characterized by comprising the steps of data acquisition of the electric boiler, calculation for the non-scaling surface temperature of the heating element of the electric boiler, calculation for the average scaling thickness of the electricheating element of the electric boiler, determination for the scaling thickness of different parts of the electric heating element of the electric boiler and the like. The heat flux density on the surface of the electric heating element immersed in the water during the operation of the electric boiler is determined according to the measured water level of the electric boiler and the actual heat exchange capacity of a working medium together, thus the temperature of the non-scaling surface of the electric heating element of the electric boiler is calculated according to a dimensionless correlation formula, which is organized by Rohsenow, of saturated nucleate boiling, then the average scaling thickness of the heating element of the electric boiler is obtained, and the scaling thickness of different parts of the electric heating element of the electric boiler is obtained according to a correction coefficient for the scaling thickness of different parts of the electric heating element, thereby achieving online accurate monitoring for the scaling thickness on the surface of the electric heating element of the electric boiler, and solving a problem that accurate online monitoring cannotbe performed on the scaling thickness of the electric heating element of the electric boiler.

The invention discloses a performance on-line monitoring device for a power distribution switch cabinet lightning arrester and a monitoring method thereof. The monitoring device comprises a microprocessor circuit, temperature signal conditioning circuits, current signal conditioning circuits, an in-cabinet temperature signal conditioning circuit, a display circuit, a keyboard circuit, a power supply circuit, a communication interface circuit in bidirectional communication connection with the microprocessor circuit, temperature sensors, current sensors and an in-cabinet temperature sensor; the temperature signal conditioning circuits, the current signal conditioning circuits, the in-cabinet temperature signal conditioning circuit, the display circuit, the keyboard circuit and the power supply circuit are in one-way communication connection with the microprocessor circuit; the temperature sensors and the current sensors are arranged on a lightning arrester in a power distribution switch cabinet, and the in-cabinet temperature sensor is arranged in the power distribution switch cabinet; and the microprocessor circuit performs on-line monitoring and a performance judgment of the lightning arrester according to acquired monitoring data. Accurate, timely and efficient on-line monitoring of performance of the lightning arrester of the power distribution switch cabinet is achieved, and, through utilization of a total leakage current of the lightning arrester and a combination with temperature data of a body of the lightning arrester, whether a fault occurs in the lightning arrester is comprehensively determined, so safe operation of switch equipment is ensured.

The invention relates to a monitoring method for LPFG (Long Period Fiber Grating) transverse load direction characteristic based on resonance amplitude modulation and an asphalt pavement pressure sensor, belonging to the field of optical sensing testing. The method comprises the following steps of: (1) demarcating a linear area of long cycle fiber Bragg grating resonance peak amplitude and transverse load relation curve; (2) during the transverse load monitoring, selecting the linear sections of all external loading varying ranges falling in the liner area, selecting the angle corresponding to the linear section of the highest sensitivity in the linear section according with the condition as a thrust surface; (3) using the characteristics of the long cycle fiber Bragg grating resonance peak amplitude and the transverse load relation to process pressure monitoring. The method is high in sensitivity and is not easy to be disturbed.

This invention relates to a kind of contact case structure of High Voltage temperature on-line monitoring that directly connect with photoelectric conversion optical fiber, belongs to high-voltage switch equipment's temperature on-line monitoring plant. The invention is a contact case structure, upper end of main body has blowhole; inlet influence power supply in interior of blowhole's inner, and power supply's feedthru connect with photoelectric transducer; embedding thermal detector on fixed unit of main body inner wall, and its feedthru connect with photoelectric transducer; top of main body set up cover at photoelectric transducer's location; opposite side of blowhole on the main body has set one penetrating slotted hole; and one side of slotted hole be furnished with ir emission tube that connect with photoelectric transducer; optical fiber penetrate slotted hole to connect with ir receiving tube on the control unit.

The invention discloses an online monitoring system for COD of high-concentration sewage. The online monitoring system comprises a sample introduction system, a dilution water flushing system, a COD analyzer and a PLC, wherein the sample introduction system comprises a sample introduction water pipe, a manual globe valve I, a Y-shaped filter, an electric globe valve III, a tee and a sampling metering pump which are sequentially connected; the dilution water flushing system comprises a dilution water flushing water pipe, a manual globe valve II, an electric globe valve I and a dilution metering pump which are sequentially connected; an output end of the sampling metering pump and an output end of the dilution metering pump are separately connected into a mixing basin; an electric globe valve II is connected between a bottom drainage opening of the mixing basin and a water drain pipe, a third interface branch pipe of the tee is connected with a manual globe valve III, and the other end of the manual globe valve III is connected with the water drain pipe; the PLC is in control connection with all the electric globe valves, all the metering pumps and the COD analyzer and is electrically connected with an HMI. According to the online monitoring system for the COD of the high-concentration sewage, the online measurement of the COD of the high-concentration sewage is facilitated, and the measurement effect is stable and reliable.

The invention relates to a multipoint temperature detection device for the test of current-carrying capacity of cross-linked cables, which comprises a on-site acquisition unit, a single conditioning unit, a data acquisition unit, a central processing unit and a direct-current power source unit from front to back of the flow direction of signals and data sequentially. The on-site acquisition unit is used for acquiring multipoint temperature data on sites, the signal conditioning unit is used for realizing high-frequency amplitude-modulation conversion of micro signals acquired by the on-site acquisition unit, the data acquisition unit is used for realizing secondary acquisition of data of the signal conditioning unit and then transmitting the acquired data to the central processing unit, and the direct-current power source unit provides direct-current power for meeting the requirement of normal running of the signal conditioning unit. The multipoint temperature detection device can monitor multipoint temperature on line quickly and accurately, and transmits data of the temperature to the next processing mechanism in a cross-link transmission manner, and is flexible in reflection and simple in structure. In addition, the number of temperature points can be increased according to test requirements within a preset range of the test, complicated process is simplified, and operation efficiency of the integral system is improved.

The invention relates to a flexible direct-current power transmission system MMC sub-modules key element synchronous online monitoring method. The method comprises the following steps that: S1, an MMC-HVDC system is constructed; S2, sensors are configured to acquire bridge arm voltage, bridge arm current and sub-module capacitor voltage; S3, a sub-module IGBT, diode and capacitor on-line monitoring mathematical model is constructed; S4, IGBT on-state voltage bias, diode on-state voltage bias, diode on-state resistance and a capacitor capacitance value are obtained online through a Kalman filtering algorithm; S5, estimated IGBT on-state voltage is calculated according to the IGBT on-state voltage bias and IGBT on-state resistance, and on-state voltage and on-state resistance are calculated;and S6, the obtained IGBT on-state voltage, the diode on-state voltage, the diode on-state resistance and the capacitor capacitance value are compared with set parameter threshold values, and aging identification and residual life estimation are carried out on sub-modules. With the method of the invention adopted, the synchronous on-line monitoring of semiconductor devices and capacitors in a monitoring MMC can be realized.

The invention provides a converter transformer tap switch vibration-electromagnetic wave combined online monitoring method. The vibration signal of the top part of a tap switch is acquired, and an electromagnetic wave signal excited by the breaking arc is acquired; the acquired vibration signal and the electromagnetic wave signal are denoised; the threshold of the wavelet coefficient when the electromagnetic wave signal is analyzed is determined by using the electromagnetic wave signal in case of normal action of the tap switch; the threshold of the wavelet coefficient when the vibration signal is analyzed is determined by using the vibration signal in case of normal action of the tap switch; the tap switch contact action time and the wavelet coefficient are determined by using the electromagnetic wave signal in case of action of the tap switch to be detected; the action time and the wavelet coefficient of each phase of the tap switch are determined by using the vibration signal in case of action of the tap switch to be detected; and the operation state of the tap switch to be detected is analyzed according to the contact action time and the wavelet coefficient. The problem that the converter transformer tap switch action event is difficult to be accurately associated by purely using the vibration signal can be effectively solved so that the operation state of the converter transformer tap switch can be accurately monitored and stable operation of the DC power transmission system can be guaranteed.

A ring-block friction wear testing machine comprises a machine body, a power driving device, a main shaft, a ring-block friction pair and a radial loading device, wherein a test ring in the ring-blockfriction pair is mounted on the main shaft; the power driving device drives the main shaft to drive the test ring to rotate; a force measuring device is arranged between the radial loading device andthe ring-block friction pair; the force measuring device mainly comprises a sample holder, a tension sensor, a hinge rod and a pull rod holder which are sequentially connected; the hinge rod is rotationally connected with the pull rod holder; the pull rod holder is fixed to the machine body; a test sample is mounted at the lower part of the sample holder; the test sample contacts with the test ring to form the ring-block friction pair; a medium channel for providing different lubricating media for the ring-block friction pair is formed in the sample holder; a loading end of the radial loadingdevice acts on the sample holder to perform radial loading and quantitative adjustment on the ring-block friction pair. The ring-block friction wear testing machine can accurately measure friction ofthe ring-block friction pair in real time, and can accurately simulate friction pair lubricating conditions under various actual working conditions.

The invention relates to an online rapid measurement apparatus and method for detecting rivet point dimension. The measurement apparatus comprises a measurement bottom plate, wherein one end of the measurement bottom plate is provided with a stretching cylinder, the cylinder is connected with a rivet point dimension detection assembly on the measurement bottom plate through a coupling, the surface of the measurement bottom plate at one side of the rivet point dimension detection assembly is provided with a sensor assembly, the sensor assembly directly faces the rivet point dimension detection assembly, and the rivet point dimension detection assembly performs side-to-side movement under the control of the stretching cylinder, and cooperates with the sensor assembly to detect rivet point dimension. The online rapid measurement apparatus and method solve the problems that online rapid measurement for the rivet point dimension cannot be performed in the prior art, an artificial detection period is long, artificial detection efficiency is low, and as there is little difference between rivet point deflections, the possibility of misjudgement is high. The online rapid measurement apparatus can perform accurate online monitoring for the rivet point dimension during mass production and after riveting, and detects whether a rivet point is qualified, accurate and reliable with high efficiency, thereby improving safety performance of the whole product, and ensuring consistency of the produced products.

The invention provides an on-line fertilizer quality monitoring system which comprises a sample conveyor belt, optical probes, a detection and control unit, V-shaped baffles and a main server monitoring device. A fertilizer sample is conveyed through the sample conveyor belt, the optical probes are installed over the sample conveyor belt, the V-shaped baffles are assembled at the front ends of the lower portions of the optical probes, and the V-shaped baffles and the lower sides of the optical probes are inserted into the fertilizer sample in the conveying process of the fertilizer sample on the sample conveyor belt; wireless communication modules are arranged in the detection and control unit, signals generated after the optical probes transmit collected spectra to the detection and control unit for light splitting and photoelectric conversion are transmitted to the wireless communication modules, the wireless communication modules comprise the CDMA communication module and the GSM communication module, and the main server monitoring device conducts modeling and quantitative analysis on the signals wirelessly received from the CDMA communication module or the GSM communication module. The on-line fertilizer quality monitoring system is convenient, efficient and accurate and cannot destroy the sample or consume chemical reagents or pollute the environment.

The invention discloses a non-radioactive device and method for rapidly and accurately monitoring ammonia. A non-radioactive ion migration spectrum of reagent molecule assisted photo ionization is utilized, under a positive ion mode, reagent molecules, namely paraxylene are optimally screened to serve as reagent molecules, and the ammonia is rapidly, accurately and highly-sensitively measured online. The detection device comprises bleached gas, a mass flow meter, carrier gas, a reagent molecular generator, an ion migration spectrum system, a vacuum pump and the like.

The invention provides an overhead power transmission line ground wire monitoring and analyzing method which comprises a ground wire monitoring module, an intelligent power transmission line ground wire operation state judgment module, a power supply module, a communication module, a data processing and analyzing module and an intelligent early warning decision module. According to the invention,a high-precision optical fiber sensing technology is introduced into ground wire monitoring, and key stress materials of an overhead transmission line tower are accurately detected so that online monitoring is more comprehensive and accurate.

The invention discloses a device for automatically regulating and controlling oxidation-reduction potential and an application thereof. The device comprises at least one fermentation tank, an oxidation-reduction potential (ORP) electrode, a central processing unit, a gas flow controller and the like, wherein the ORP electrode is used for measuring the oxidation-reduction potential in the fermentation tank, the central processing unit is used for receiving a signal of the ORP electrode and comparing the signal of the ORP electrode with the signal value preset by a user or a signal spacing value to generate a control signal; and the gas flow controller is used for receiving the control signal of the central processing unit and controlling the flow speed of gas which leads to the fermentation tank according the control signal. The device systematically integrates processes of oxidation-reduction potential on-line monitoring, signal processing and feedback control and the like, can be used for optimizing the oxidation-reduction potential of a fermentation system to improve the fermentation yield, and also can be used for screening novel industrial production bacterial strains with good properties, and optimizing the production performance of the bacterial strains. Due to the development, the device also can be used for synchronizing the monitoring process of the oxidation-reduction potential with the automatic monitoring process of the other fermentation control, further the synergistic effect of the device is improved.

The invention provides an on-line monitoring method for insulated equipment. The method comprises the following steps: monitoring the on-line monitoring data generated by on-line monitoring of the insulated equipment in real time; generating a corresponding model document in a set modeling manner according to the on-line monitoring data; and uploading the model document to a remote monitoring and diagnosis center. By adopting the technology provided by the invention, the real-time monitoring data of insulated components can be managed in a unified manner, the remote monitoring and diagnosis center can accurately and more comprehensively monitor the states of both a main circuit and a load-center substation on line, and the operation stability and reliability of a power grid are improved.

The invention discloses transformer substation power quality monitoring system, the system comprises a central processing module, voltage measuring module, an electric current measuring module, a frequency monitoring module, a flicker test module, a display module and an alarm module, wherein the electric current measuring module comprises a fundamental current measuring module and a harmonic current measuring module, the central processing module is used for converting a measured analog signal into a digital signal and processing and displaying through the display module, the alarm module is used for transmitting an alarm message when the voltage, electric current or frequency signal has exceptions. The system can accurately and timely monitor the power quality of the transformer substation online, the following conditions caused by the poor power quality can be avoided, including: the monitoring can not be acquired, the user electrical equipment is damaged, and the system unstably operates.

The invention discloses a corrosion-resistant protein enamel pot and an application. The corrosion-resistant protein enamel pot comprises an enamel pot 1, a condenser, and an enamel pot 2. The condenser is arranged at the upper part of the enamel pot, and the enamel pot 1 and the enamel pot 2 are equipped at the lower part of the enamel pot. A pot body of the enamel pot 1 and the enamel pot 1 are connected to the condenser through pipelines. A flange connecting an upper seal head of the enamel pot 1 and the pot body is firmly locked via double-end studs; a polytetrafluoroethylene O-shaped flange gasket is arranged between the pot body and the seal head; and the pot body and the seal head are fixed through a loose flange. Defects that the function is single; only heating, cooling, and stirring can be performed, and distillation of most acid liquids cannot be satisfied; and a waste liquid in a jacket cannot be directly discharged, of an existing enamel pot are overcome. The corrosion-resistant protein enamel pot has advantages of simple structure, convenient installation and disassembly, and accurate on-line monitoring, and is safe and reliable in a use process. According to the corrosion-resistant protein enamel pot, technology of hydrolyzing protein is easy to control; a hydrolysis liquid is stable in quality and convenient to store; and requirements of technology, such as chromatography and refining, can be satisfied. The total nitrogen recovery rate detected in the obtained hydrolyzed protein can reach 80%.

The invention belongs to the technical field of industrial control and relates to an on-line monitoring device for methane and non-methane total hydrocarbon so as to solve the problems that an existing detection device is low in detection speed and complicated. The device includes a mid-infrared LED, a near-infrared laser, an electro-optic modulator, an optical filter, a gas absorption pool, a beam splitting prism, a pyroelectric mid-infrared detector, a near-infrared photodiode, a full-wave rectifier bridge, an analog-digital converter and a sampling device. The mid-infrared LED light sourceand the near-infrared semiconductor laser are adopted, and the concentration of the methane and the concentration of the total hydrocarbon are measured at the same time by using the same optical gas absorption pool. The external modulation technology is used for modulating a mid-infrared light source and a near-infrared light source at the same frequency synchronously, multiple reflections are realized through a reflection lens, optical paths are increased to improve the sensitivity of gas detection, and the adoption of the photoelectric detector of different wavebands can avoid mutual interference between different measured components.

The invention relates to a parallel lightning arrester group breakdown monitoring method based on grating temperature measurement. The method is characterized by comprising the following steps: uniformly installing optical fiber grating temperature sensors on the outer walls of the insulating porcelain insulators of a lightning arrester set, collecting the temperature data of the lightning arrester set, demodulating an obtained optical signal into a digital signal by means of a data acquisition device, packaging the digital signal through a wireless transceiving device, and transmitting the signal to a data processing device in a wireless mode; sending out an alarm when the data processing device finds that the temperature of the lightning arrester set exceeds a threshold value. Trials show that, the method can effectively solve the problems of electromagnetic interference and dynamic characteristics, and improve the reliability of use. The method further has the following advantages:the temperature data of a lightning arrester can be monitored accurately and timely under the condition that the normal working condition of the lightning arrester of a direct-current circuit breakeris not influenced at all. Meanwhile, an alarm is given out when the lightning arrester is broken down.