Optical-fiber intelligent sensing power cable method for monitoring operation states and device
Technical field:
The invention belongs to technical field of optical fiber sensing, relate to a kind of optical-fiber intelligent sensing power cable method for monitoring operation states and device.
Background technology:
Power industry belongs to the basic activity of national economic development, in national economic development, there is very important status, along with economic fast development, every country is all increasing day by day to the demand of electric power, causes rated voltage and rated current grade in electric system to improve year by year.Due to the decline of power cable application cost, and the power supply reliability that power cable self has is high, the impact that is not subject to ground, space buildings thing, be not subject to weather extremes infringement, the feature such as durable safe and out of sight, thereby obtain more and more widely application, especially in city, generating plant and congested area, transformer station's line corridor, large rivers and lakes or area, straits, when overhead transmission line can not be adopted, need to adopt power cable transmission of electricity.Compared with overhead transmission line, the above-mentioned advantage of power cable but for the maintenance work of later stage cable particularly fault localization brought the features such as larger difficulty, especially line fault unobservability all to determine that cable line requirement has more accurate fault monitoring method with location; On the other hand, power cable is as the important component part of whole electric system, the safe operation of whole electric system will directly be affected once break down, and as fault discovery not in time, may cause the damage sequence that fire, massive blackout etc. are larger, therefore how to search quickly and accurately power cable fault, reduce fault restoration expense and loss of outage, become the problem of power engineering field and research circle's growing interest.
Power cable line mostly adopts direct burial, framework type and the mode such as lays under water, because of laying environment, soil thermal resistance, close on the radiating condition differences such as thermal source on the way, tend to cause cable line to occur local hot spot and form current-carrying capacity ink-bottle effect, if now only determine cable line current-carrying capacity and load capacity according to criterion calculation result or partial points temperature measurement result, may cause circuit minor insulation overheated and the interruption of service of electricity-thermal breakdown occurs; On the other hand, when local defect, insulation breakdown omen and unexpected fire etc. in power cable or annex medium all can cause System for Surface Temperatures of Power Cables to occur abnormal thermal effect to some extent.Between the electrical equipments such as the isolating switch of electric system, transformer, cable, bus, switch cubicle by connections such as bus, lead-in wire, cables, because electric current flows through generation heat, so nearly all electric fault all can cause the variation of trouble spot temperature.Compared with power cable body, power cable terminal and intermediate head weak link especially, that is to say that the quality of power cable body, terminal and intermediate head structure directly has influence on the safe operation of power cable line.
Due to the restriction of technical merit, make the safe operation of electric system power cable be subject to certain limitation for many years, the method for originally insulate after regularly power failure of main dependence prevention and testing circuit has been difficult to meet real requirement.Many researchers have proposed some new online charged detection methods in recent years, and these methods are to early detection power cable, and insulation defect and aging conditions that particularly twisted polyethylene cable exists have effect very much, conventionally have following several method:
(1) DC superposition method: the neutral point place at the voltage transformer (VT) of ground connection adds low-voltage dc power supply, make the alternating voltage stack of this DC voltage and cable in service, detect the atomic weak DC current by cable insulation, can record the insulation resistance of whole piece cable, thereby judge the quality of cable.The feature of DC superposition method is that antijamming capability is stronger, but the correlativity of insulation resistance and cable insulation residual life bad, dispersiveness is quite large.
(2) DC component method: by atomic weak flip-flop in detection streamer heart yearn and screen layer electric current, in cable certain a bit or a certain local branch (water tree, the electric branch) insulation defect existing carry out deteriorated diagnosis.A little less than electric current that DC component method records is atomic, sometimes also not quite stable, small interference current will cause very large error.
(3) dielectric dissipation factor method: the voltage voltage transformer (VT) or the voltage divider that are added on cable are taken out, the power current Current Transformer flowing through in insulation is taken out, then in self-poise loop, detect the phase differential of above-mentioned signal, can measure the dielectric dissipation factor of cable insulation.
(4) thermopair, semiconductor temperature sensor, electronic temp instrumentation warm therapy: because each monitoring point needs power supply, wiring, wiring complexity and electromagnetic interference (EMI) is serious, fragile, maintenance is large; Sensor does not possess self-checking function, needs frequent verification.
(5) temperature sensing cable formula temp measuring system: by temperature sensing cable and cable parallelization, in the time that cable temperature exceedes fixed temperature value, sensing cable is by short circuit.System only can disposablely be used, and can not measure the actual temperature value of cable; Because number of cables is many, system installation and maintenance work are convenient not, and equipment is fragile; Can not carry out fault forecast, display measurement value in real time, without temperature trend analysis.
(6) infrared imaging temperature measuring method: be mainly applicable to the position such as outdoor terminal and cable connection point and earth point, be vulnerable to power cable surrounding environment change, the impact of electromagnetic interference (EMI), aerosol impact and object emissivity.
(7) distributed optical fiber temperature sensor: realize cable fault location by near temperature variations fault inspecting, because measured temperature is the medial temperature within the scope of, precision is not high, can not accurately reflect the temperature of each point, the temperature of cable core.
Summary of the invention:
The present invention is directed to above-mentioned the deficiencies in the prior art: provide a kind of optical-fiber intelligent sensing power cable method for monitoring operation states and device.This device volume is little, lightweight, simple in structure, without electromagnetic interference (EMI), good stability, essence insulation, do not need to connect external power, can the multi-thread real-time measurement of multiple spot, be applicable to the monitoring of single core, multicore, multiple spot, many power cables (as follows) running status, real-time current, real time temperature, electrical network phase current, overload state, localization of fault, the anti-theft that can obtain the operation of power cable are antitheft, environment temperature monitoring and illegal invasion situation etc.
The technical solution adopted in the present invention is:
A kind of optical-fiber intelligent sensing power cable method for monitoring operation states, it is characterized in that, the susceptibility of Fibre Optical Sensor based in optical fiber sensing probe to temperature, stress and strain, the optical fiber power cable intelligent sensor of multiple optical fiber sensing probes being set up by auxiliary clamp is fixed on the cable surrounding of Operation Condition for Power Cable monitoring point, the running temperature of Real-Time Monitoring power cable, by the temperature field of digital reconstruction power cable, Real-Time Monitoring Operation Condition for Power Cable and running quality.
Optical-fiber intelligent sensing power cable method for monitoring operation states of the present invention device used, it comprises one or more optical fiber power cable intelligent sensors, Transmission Fibers, data analysis and treating apparatus; Described optical fiber power cable intelligent sensor, for multiple optical fiber sensing probes utilize the parts of the similar thin wall circular structure that one or more auxiliary clamps and one or more auxiliary part be packaged into along the radial and axial layering of power cable, fit over power cable surrounding, described multiple optical fiber sensing probes connect described Transmission Fibers, its Transmission Fibers connection data is analyzed and treating apparatus, and tested Temperature of Power Cables signal is transferred to data analysis and treating apparatus analyzing and processing Monitoring Data.
In technical scheme of the present invention, described auxiliary clamp, auxiliary part, optical fiber power cable intelligent sensor and Transmission Fibers, be designed to and tested power cable size and the required shape of actual measurement environmental requirement.
In technical scheme of the present invention, optical fiber sensing probe, auxiliary clamp, auxiliary part, optical fiber power cable intelligent sensor, Transmission Fibers all adopt insulating material insulation.
In technical scheme of the present invention, optical fiber sensing probe utilizes Fibre Optical Sensor cable running status, or utilizes optical fiber grating sensing Operation Condition for Power Cable.
In technical scheme of the present invention, in data analysis and treating apparatus, according to actual environment and the power cable of one or more power cable of laying, preset the installation environment parameter of power cable and the structural parameters of power cable.
The using method of optical-fiber intelligent sensing power cable monitoring running state device of the present invention: optical fiber power cable intelligent sensor is according to tested power cable dimensioned, and being fixed on power cable monitoring point by auxiliary clamp and auxiliary part, the optical fiber sensing probe output signal in optical fiber power cable intelligent sensor is transported to data analysis and treating apparatus through Transmission Fibers; By data analysis and the installation environment parameter of the default power cable for the treatment of apparatus and the structural parameters of power cable, the theoretical running status of calculating power cable; In the time of power cable current-carrying, the metal guide of power cable core is known from experience heating, and gradually to the outer heat radiation of power cable cable, the signal intensity of the optical fiber sensing probe in optical fiber power cable intelligent sensor, carries out obtaining power cable structure real-time running state after data processing and analysis through data analysis and treating apparatus.
The optical fiber sensing probe of optical-fiber intelligent sensing power cable monitoring running state device of the present invention, Real-Time Monitoring Temperature of Power Cables, auxiliary clamp and auxiliary part are encapsulated into multiple optical fiber sensing probes in optical fiber power cable intelligent sensor, Transmission Fibers is transmitted tested Temperature of Power Cables signal to data analysis and treating apparatus, and data analysis and treating apparatus are preset, preanalysis power cable relevant parameters analyzing and processing Monitoring Data.
The application of optical-fiber intelligent sensing power cable monitoring running state device of the present invention: in the time of power cable current-carrying, the metal guide of electric-cable core is known from experience heating, and gradually to the outer heat radiation of electric-cable core, by the optical fiber sensing probe in optical fiber power cable intelligent sensor, can monitor in real time the radial and axial temperature signal of power cable.In the time that the current signal of power cable changes, the metallic conductor heating of power cable core is different, cause the transducing signal of the multiple optical fiber sensing probes in optical fiber power cable intelligent sensor to change thereupon, and deliver to data analysis and treating apparatus carries out data processing and analysis by Transmission Fibers, obtain the real-time running state of power cable.
The present invention is encapsulated into multiple optical fiber sensing probes in optical fiber power cable intelligent sensor by auxiliary clamp and auxiliary part, and the radial and axial temperature of Real-Time Monitoring power cable, for the temperature field of digital reconstruction electric-cable core provides parameter.
Data analysis in the present invention and treating apparatus can carry out theoretical analysis and calculating according to actual environment and the power cable parameter of many power cables of laying, the ruuning situation of theoretical prediction power cable, such as: electric load situation, electric power power cable current conditions etc., calculate and analyze for the actual motion status monitoring of power cable carries out theory.
Data analysis in the present invention and treating apparatus are analyzed multiple optical fiber sensing probe Monitoring Data of many multiple spot Operation Condition for Power Cable monitoring points, can obtain operational monitoring and the analysis of the running status of power cable, such as: power cable real-time current, real time temperature, electrical network phase current, overload state, localization of fault, anti-theft are antitheft, environment temperature monitoring, illegal invasion situation etc., effectively the febrile state of monitoring power cable at different loads and varying environment temperature, accumulates historical technical data; Current-carrying capacity limit is analyzed, and ensures to allow running temperature in the situation that being no more than cable, bring into play to greatest extent cable transmittability, increase economic efficiency; Find the local hot spot on cable, take in time to fall stream cooling measure, delay cable aging speed; Real time fail monitoring and warning, finds the destruction that in cable operational process, extraneous factor causes; Power cable fire monitoring and warning; The temperature monitoring of cable splice, cable termination and warning.
Advantage of the present invention: this device can be realized the structure monitoring of the multichannel multiple spot of power cable, and measuring accuracy and resolution are high; Sensing signal and signal transmission are light signal, are not subject to the impact of electromagnetic interference (EMI), not vibrated and nuclear radiation; Good environmental adaptability, good stability, can be for a long time for high temperature, high humidity and there are the rugged surroundings of chemical erosion etc.; Lightweight, volume is little, easy to install, and essence insulation, does not need to connect external power.
Brief description of the drawings:
Fig. 1 is optical fiber power cable intelligent sensor structural representation,
Fig. 2 is optical fiber power cable intelligent sensor section of structure,
Fig. 3 is an embodiment of optical-fiber intelligent sensing power cable monitoring running state device,
In figure: 1-optical fiber sensing probe, 2-auxiliary clamp, 3-auxiliary part, 4-optical fiber power cable intelligent sensor, 5-Transmission Fibers, 6-data analysis and treating apparatus.
Embodiment:
A kind of optical-fiber intelligent sensing power cable monitoring running state device of the present invention is as shown in Figure 1, Figure 2 shown in Fig. 3, and it comprises one or more optical fiber power cable intelligent sensors 4, Transmission Fibers 5, data analysis and treating apparatus 6; To be multiple optical fiber sensing probes 1 utilize the parts of the similar thin wall circular structure that one or more auxiliary clamps 2 and one or more auxiliary part 3 be packaged into along the radial and axial layering of power cable with described optical fiber power cable intelligent sensor, be fixed on power cable, described multiple optical fiber sensing probes 1 connect described Transmission Fibers 5, its Transmission Fibers 5 connection data analyses and treating apparatus 6, be transferred to data analysis and treating apparatus analyzing and processing Monitoring Data by tested Temperature of Power Cables signal.
This optical-fiber intelligent sensing power cable monitoring running state device principle of work: in the time of power cable current-carrying, the metal guide of electric-cable core is known from experience heating, and gradually to the outer heat radiation of electric-cable core, by the optical fiber sensing probe 1 in optical fiber power cable intelligent sensor 4, can monitor in real time the radial and axial temperature signal of power cable; In the time that the current signal of power cable changes, the metallic conductor heating of power cable core is different, cause the transducing signal of the multiple optical fiber sensing probes 1 in optical fiber power cable intelligent sensor 4 to change, and deliver to data analysis and treating apparatus 6 carries out data processing and analysis by Transmission Fibers 5, obtain stolen and electrical network phase current situation of real time execution temperature, real-time current, overload operation state, network load state, power cable fault, the power cable of power cable etc.
The present invention is encapsulated into multiple optical fiber sensing probes 1 in optical fiber power cable intelligent sensor 4 by auxiliary clamp 2 and auxiliary part 3, and the radial and axial temperature of Real-Time Monitoring power cable, for the temperature field of digital reconstruction power cable provides parameter.
The sensitivity that the present invention requires according to the physical size of power cable, shape and structure monitoring, and the needs of measurement range, adopt different optical fiber sensing probes 1, auxiliary clamp 2 and auxiliary part 3 to be encapsulated in optical fiber power cable intelligent sensor 4, make it be applicable to the monitoring needs of different power cable structures.
Data analysis in the present invention and treating apparatus 6 carry out theoretical analysis and calculating according to actual environment and the power cable parameter of many power cables of laying, the electric load of theoretical prediction power cable, current conditions etc., calculate and analyze for the actual motion status monitoring of power cable carries out theory.
The data analysis of the technical solution adopted in the present invention and treating apparatus are analyzed optical-fiber intelligent power cable sensing probe 4 Monitoring Data of many multiple spot Operation Condition for Power Cable monitoring points, can obtain operational monitoring and the analysis of the running status of power cable, such as: power cable real-time current, real time temperature, electrical network phase current, overload state, localization of fault, anti-theft are antitheft, environment temperature monitoring and illegal invasion etc., effectively the febrile state of monitoring power cable at different loads and varying environment temperature, accumulates historical technical data; Current-carrying capacity limit is analyzed, and ensures to allow running temperature in the situation that being no more than cable, bring into play to greatest extent cable transmittability, increase economic efficiency; Find the local hot spot on cable, take in time to fall stream cooling measure, delay cable aging speed; Real time fail monitoring and warning, finds the destruction that in cable operational process, extraneous factor causes; Power cable fire monitoring and warning; The temperature monitoring of cable splice, cable termination and warning.
Describe the present invention below by embodiment, but be not limited to embodiment.
Embodiment 1
Figure 3 shows that one embodiment of the present of invention, optical-fiber intelligent sensing power cable monitoring running state device comprises three optical fiber power cable intelligent sensors 4, Transmission Fibers 5, data analysis and a treating apparatus 6; Its three optical fiber power cable intelligent sensors are connected with treating apparatus with data analysis by Transmission Fibers.In the time of power cable current-carrying, the metal guide of power cable core is known from experience heating, and gradually to the outer heat radiation of power cable cable, by the optical fiber sensing probe 1 in optical fiber power cable intelligent sensor 4, monitor in real time the radial and axial thermograde field signal of power cable.In the time that the current signal of power cable changes, the metallic conductor heating of power cable core is different, cause the sensing signal of optical fiber sensing probe 1 to change, and deliver to data analysis and treating apparatus 6 carries out data processing and analysis by Transmission Fibers 5, obtain power cable structure real-time running state.
Its using method is as follows: by auxiliary clamp 2, auxiliary part 3, optical fiber power cable intelligent sensor 4 is fixed on power cable, optical fiber sensing probe 1 output signal in optical fiber power cable intelligent sensor 4 is transported to data analysis and treating apparatus 6 through Transmission Fibers 5; By data analysis and the installation environment parameter for the treatment of apparatus 6 default power cables and the structural parameters of power cable, the theoretical running status of calculating power cable; In the time of power cable current-carrying, the metal guide of power cable core is known from experience heating, and gradually to the outer heat radiation of power cable cable, the signal intensity of the optical fiber sensing probe 1 in optical fiber power cable intelligent sensor 4, carries out obtaining power cable structure real-time running state after data processing and analysis through data analysis and treating apparatus 6.
In use procedure, should make 4 fixed installations of optical fiber power cable intelligent sensor steadily, avoid introducing external vibration and disturb, transducing signal is impacted.