CN102768183B - System and method for online monitoring filth of fiber bragg grating transmission line - Google Patents

Abstract

The invention discloses a system for online monitoring filth of a fiber bragg grating transmission line which belongs to the technical field of online monitoring of power lines. The system comprises a computer, a wavelength demodulating system, a junction box, junction box output optical fiber, a thermometer screen, a first lead-out optical fiber, a second lead-out optical fiber, a fiber bragg grating filth sensor array and a fiber bragg grating compensation sensor, wherein the wavelength demodulating system comprises a solar power generation module and a wireless communication module. According to the system provided by the invention, salt density and ash density are accurately measured so that the system is suitable for being used in a strong electromagnetic environment and a severe temperature and humidity environment of an insulator.

Description

A kind of Fiber Bragg Grating transmission line of electricity contamination on-line monitoring system and method

Technical field

The invention belongs to power circuit on-line monitoring technique field, relate in particular to a kind of Fiber Bragg Grating transmission line of electricity contamination on-line monitoring system and method.

Background technology

Since the nineties in 20th century, electric grid large area pollution flashover accident occurs on a large scale again and again in the whole nation, and the safe operation of electric system in serious threat.The basic reason of transmission line of electricity pollution flashover accident is that insulator surface has deposited filthy material, after it has absorbed the moisture in humid air, dielectric strength is sharply declined, and bears incessantly operating voltage and flashover occurs.The reliable detection of insulator contamination degree is conducive to electric power maintenance personnel and grasps timely and accurately insulator contamination situation, is a very important ring in anti-pollution flashover work.Meanwhile, pollution level detects and can guarantee that dirty Division is accurate reliably, thereby provides scientific basis for power transmission and transformation equipment outer insulation designs with Insulator Selection, is the basic guarantee that prevents large area pollution flashover accident.

On-line monitoring can effectively be followed the tracks of the change procedure of insulator contamination, makes it early warning in advance in the time that pollution level reaches critical conditions, is convenient to work about electric power personnel and takes early counter-measure, prevents the generation of pollution flashover accident.Many experts and scholars of domestic Tsing-Hua University, Chinese DianKeYuan, University Of Chongqing, North China Electric Power University, Xi'an Communications University, South China Science & Engineering University, Neng Duosuo institution of higher learning of Harbin University of Science and Technology and research institution have carried out a large amount of fruitful work in this field, and have developed a large amount of on-line measuring devices.At present, the filthy detection means of high-tension insulator and method comprise both at home and abroad: microwave irradiation, UV pulse method, infrared imaging method, acoustic-emission, leakage current method and photon flux method.Microwave irradiation, due to filthy complicated component, measurement result is difficult to corresponding with filthy composition; Ultraviolet method and infrared method, because ultraviolet, the optical measuring apparatus such as infrared are expensive, fragile and need power consumption larger, be not suitable for long-term on-line monitoring; Acoustic-emission, because near electromagnetic environment transmission of electricity is severe, noise is larger, and acoustic-emission receives signal and is easy to be submerged, and is difficult to obtain true filthy situation.Applying at the scene more is Leakage Current method and spectroscopic methodology.

Leakage current is the result of working voltage, pollution level, the combined action of weather conditions three elements, is dynamic parameter, suitable on-line monitoring.Flow through the leakage current of insulator surface by leakage current sensor Real-time Obtaining, formed a large amount of electric transmission line isolator contamination on-line monitoring systems.Tsing-Hua University closes will and becomes the research of teach problem group lot of experiments to show: to studied model insulator, leakage current maximal value and filthy state relation are obvious, can be used for the assessment of filthy degree.

The research of On-line Monitoring of Leakage Current technology is carried out for many years, but still has a large amount of problems in actual applications.Subject matter has: 1) many factors such as close, the meteorological condition of the size of leakage current and the type of insulator used (material, umbellate form, disk track), filthy composition, equivalent salt density (ESDD), ash is relevant, is difficult to utilize Leakage Current assessment insulator contamination level; 2) judge insulator operation conditions and early warning interval according to leakage current, also do not have at present authoritative standard to follow, do not accumulate abundant service data yet, also will rely on operating personnel's experience to determine cleaning or maintenance critical value, its accuracy is not high; 3) running environment of device is more severe, and reliability is not high; 4) due to shortcomings such as measuring system are carried out specialized designs near environment outdoor transmission line of electricity, and existence is subject to electromagnetic interference (EMI), and aging speed is fast.

Photon flux method successfully solved that Leakage Current method can not directly not measured filth amount and anti-electromagnetic interference capability a little less than shortcoming, its theoretical foundation is the theoretical and luminous energy loss mechanism of the optical field distribution in dielectric optical waveguide.In the time having pollution on quartz glass bar, because pollutant has changed the transmission conditions of higher mode and basic mode, meanwhile, contaminant particles can produce luminous energy loss to absorption and the scattering etc. of luminous energy, by detect luminous energy parameter can calculate sensor surface salinity number.Once had scholar to attempt by the relation of neural network luminous flux, humidity, dust ratio and ESDD, but because sample size is less, this research is still insufficient.

The close on-line monitoring system of spectroscopic methodology salt is in recent years at northern China some areas hanging net operation, but this system is not yet promoted the use of in each Utilities Electric Co. at present, the accuracy that is mainly equivalent salt density measurement is still to be tested, there is fatal shortcoming in luminous intensity measurement simultaneously, owing to having adopted light intensity as monitoring variable, the labile factor of optical component has considerable influence to measurement result.Meanwhile, this system can not directly be measured ash is close, also needs further research for the relation between luminous flux attenuation and humidity, dust ratio and ESDD.

Summary of the invention

The deficiencies such as ash is close, measurement result is easily disturbed be cannot measure for mentioning existing on-line monitoring system in above-mentioned background technology, a kind of Fiber Bragg Grating transmission line of electricity contamination on-line monitoring system and method the present invention proposes.

Technical scheme of the present invention is, a kind of Fiber Bragg Grating transmission line of electricity contamination on-line monitoring system, is characterized in that this system comprises that computing machine, Wavelength demodulation system, terminal box, terminal box are exported optical cable, thermometer screen, first is drawn optical fiber, second and drawn optical fiber, Fiber Bragg Grating pollution sensor array and Fiber Bragg Grating compensation sensor;

Described Wavelength demodulation system comprises solar electrical energy generation module and wireless communication module;

Described computing machine is connected with Wavelength demodulation system; Wavelength demodulation system is exported optical cable by terminal box and is connected with terminal box; Terminal box is drawn optical fiber and second by first and is drawn optical fiber and be connected with Fiber Bragg Grating pollution sensor array and Fiber Bragg Grating compensation sensor respectively; Fiber Bragg Grating compensation sensor is placed in thermometer screen;

Described Fiber Bragg Grating pollution sensor array is made up of the first Fiber Bragg Grating pollution sensor and the second Fiber Bragg Grating pollution sensor, and the first Fiber Bragg Grating pollution sensor is the Fiber Bragg Grating that applies the first setting thickness humidity-sensitive material; The second Fiber Bragg Grating pollution sensor is the Fiber Bragg Grating that applies the second setting thickness humidity-sensitive material;

The half of described Fiber Bragg Grating compensation sensor is the Fiber Bragg Grating that applies the 3rd setting thickness humidity-sensitive material, second half of Fiber Bragg Grating compensation sensor be not for applying the Fiber Bragg Grating of humidity-sensitive material, and Fiber Bragg Grating compensation sensor adds moisture-inhibiting dust-proof sheath;

Described Wavelength demodulation system is for carrying out demodulation to the wavelength of Fiber Bragg Grating pollution sensor array and the collection of Fiber Bragg Grating compensation sensor;

It is close and grey close that described computing machine utilizes wavelength data to calculate acquisition salt.

Described terminal box output optical cable is OPGW optical, All Dielectric self-support ADSS, OPPC optical cable or armored optical cable.

The connected mode of described the first Fiber Bragg Grating pollution sensor and the second Fiber Bragg Grating pollution sensor is serial or parallel connection.

Described humidity-sensitive material is polyimide or hydrogel.

Described computing machine is connected by netting twine or wireless communication module with Wavelength demodulation system.

When described computing machine is connected by netting twine with Wavelength demodulation system, Wavelength demodulation system passes through mains-supplied.

When described computing machine is connected by wireless communication module with Wavelength demodulation system, Wavelength demodulation system is by solar electrical energy generation module for power supply.

A method for the filthy on-line monitoring of transmission line of electricity, is characterized in that the method comprises the following steps:

Step 1: the assigned address that described terminal box, thermometer screen, Fiber Bragg Grating pollution sensor array and Fiber Bragg Grating compensation sensor is placed in to power transmission line;

Step 2: by the data of described Fiber Bragg Grating pollution sensor array and the collection of Fiber Bragg Grating compensation sensor, be sent to described Wavelength demodulation system by described terminal box;

Step 3: demodulation Bragg wavelength data are out sent to described computing machine by described Wavelength demodulation system;

Step 4: it is close and grey close that described computing machine calculates salt according to demodulation Bragg wavelength data out.

The computing formula of described Fiber Bragg Grating compensation sensor temperature and humidity is:

$\left\{\begin{array}{c}{\mathrm{\λ}}_3={\mathrm{\α}}_{T3}T+{\mathrm{\α}}_{H3}H\\ {\mathrm{\λ}}_4={\mathrm{\α}}_{T4}T+{\mathrm{\α}}_{H4}H\end{array}\right.$

λ ₃for Fiber Bragg Grating compensation sensor applies the Bragg wavelength that humidity-sensitive material part obtains;

λ ₄for Fiber Bragg Grating compensation sensor does not apply the Bragg wavelength that humidity-sensitive material part obtains;

α _t3for Fiber Bragg Grating compensation sensor applies Bragg wavelength that humidity-sensitive material part the obtains sensitivity coefficient to temperature;

α _t4for Fiber Bragg Grating compensation sensor does not apply Bragg wavelength that humidity-sensitive material part the obtains sensitivity coefficient to temperature;

α _h3for Fiber Bragg Grating compensation sensor applies Bragg wavelength that humidity-sensitive material part the obtains sensitivity coefficient to humidity;

α _h4for Fiber Bragg Grating compensation sensor does not apply Bragg wavelength that humidity-sensitive material part the obtains sensitivity coefficient to humidity;

T is temperature;

H is humidity.

Close and the grey close computing formula of described salt is:

$\left\{\begin{array}{c}{\mathrm{\λ}}_1={\mathrm{\α}}_{T1}T+{\mathrm{\α}}_{H1}H+{\mathrm{\α}}_{S1}S+{\mathrm{\α}}_{A1}A\\ {\mathrm{\λ}}_2={\mathrm{\α}}_{T2}T+{\mathrm{\α}}_{H2}H+{\mathrm{\α}}_{S2}S+{\mathrm{\α}}_{A2}A\end{array}\right.$

Wherein:

λ ₁it is the Bragg wavelength of the first Fiber Bragg Grating pollution sensor;

λ ₂it is the Bragg wavelength of the second Fiber Bragg Grating pollution sensor;

α _t1be that the Bragg wavelength of the first Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of temperature;

α _t2be that the Bragg wavelength of the second Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of temperature;

α _h1be that the Bragg wavelength of the first Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of humidity;

α _h2be that the Bragg wavelength of the second Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of humidity;

α _s1be that the Bragg wavelength of the first Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of salinity;

α _s2be that the Bragg wavelength of the second Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of salinity;

α _a1be that the Bragg wavelength of the first Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of gray scale;

α _a2be that the Bragg wavelength of the second Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of gray scale;

S is salinity;

A is gray scale.

The invention solves prior art poor accuracy, can not carry out the shortcoming of the close and grey close measurement of salt accurately.The plurality of advantages such as the anti-electromagnetic interference (EMI) of native system, stable performance, monitoring distance be long, be not subject to that light intensity affects, are particularly suitable for using in the residing strong electromagnetic environment of insulator and severe humiture environment.

Accompanying drawing explanation

Fig. 1 is Fiber Bragg Grating pollution sensor schematic diagram;

Fig. 2 is Fiber Bragg Grating pollution sensor site layout project figure;

Fig. 3 is partial data in " wet sensitive coating thickness-humidity-salt is close-ash is close-red shift amplitude-red shift response time " database.

Embodiment

Below in conjunction with accompanying drawing, preferred embodiment is elaborated.Should be emphasized that, following explanation is only exemplary, rather than in order to limit the scope of the invention and to apply.

The problems referred to above that exist for overcoming prior art, the present invention adopts Fiber Bragg Grating (FBG) to carry out the filthy on-line monitoring of electric transmission line isolator.Because FBG has, anti-electromagnetic interference (EMI), stable performance, monitoring distance are long, the plurality of advantages that is not subject to that light intensity affects etc., are particularly suitable for using in the residing strong electromagnetic environment of insulator and severe humiture environment.But because the characteristic quantity Bragg wavelength of FBG is only to temperature and strain sensitive, has no idea at present directly to apply Fiber Bragg Grating FBG and filth is carried out to the measurement of salinity or ash content.

The installation position of Wavelength demodulation system is equipped with two kinds of modes in shaft tower and transformer station, when Wavelength demodulation system is positioned on shaft tower, Wavelength demodulation system is connected with computing machine by wireless mode, and when Wavelength demodulation system is arranged in transformer station, Wavelength demodulation system is connected with computing machine by wireless mode.The wavelength signals of output is sent to computing machine by Wavelength demodulation system, and it is close and grey close that computing machine utilizes wavelength data to calculate acquisition salt according to built-in algorithms.

The principle of Fiber Bragg Grating pollution sensor is that salinity or grey branch suppress Fiber Bragg Grating surface humidity-sensitive material water absorbing capacity and absorption speed, close and grey close by the monitoring reflection salt to fiber-optic bragg grating sensor wavelength.

The present invention includes computing machine, Wavelength demodulation system, terminal box, terminal box output optical cable, thermometer screen, first is drawn optical fiber, second and is drawn optical fiber, Fiber Bragg Grating pollution sensor array and Fiber Bragg Grating compensation sensor; Wavelength demodulation system comprises solar electrical energy generation module and wireless communication module; Computing machine is connected with Wavelength demodulation system; Wavelength demodulation system is exported optical cable by terminal box and is connected with terminal box; Terminal box is drawn optical fiber and second by first and is drawn optical fiber and be connected with Fiber Bragg Grating pollution sensor array and Fiber Bragg Grating compensation sensor respectively; Fiber Bragg Grating compensation sensor is placed in thermometer screen; Fiber Bragg Grating pollution sensor array is made up of the first Fiber Bragg Grating pollution sensor and the second Fiber Bragg Grating pollution sensor, and the first Fiber Bragg Grating pollution sensor is the Fiber Bragg Grating that applies the first setting thickness humidity-sensitive material; The second Fiber Bragg Grating pollution sensor is the Fiber Bragg Grating that applies the second setting thickness humidity-sensitive material; The half of Fiber Bragg Grating compensation sensor is the Fiber Bragg Grating that applies the 3rd setting thickness humidity-sensitive material, second half of Fiber Bragg Grating compensation sensor be not for applying the Fiber Bragg Grating of humidity-sensitive material, and Fiber Bragg Grating compensation sensor adds moisture-inhibiting dust-proof sheath; Wavelength demodulation system is for carrying out demodulation to the wavelength of Fiber Bragg Grating pollution sensor array and the collection of Fiber Bragg Grating compensation sensor; It is close and grey close that computing machine utilizes wavelength data to calculate acquisition salt.

Terminal box output optical cable is OPGW optical, All Dielectric self-support ADSS or OPPC optical cable; The connected mode of the first Fiber Bragg Grating pollution sensor and the second Fiber Bragg Grating pollution sensor is serial or parallel connection; Humidity-sensitive material is polyimide or hydrogel; Computing machine is connected by netting twine or wireless communication module with Wavelength demodulation system; When computing machine is connected by netting twine with Wavelength demodulation system, Wavelength demodulation system passes through mains-supplied; When computing machine is connected by wireless communication module with Wavelength demodulation system, Wavelength demodulation system is by solar electrical energy generation module for power supply.

The Bragg wavelength of the first Fiber Bragg Grating pollution sensor and the second Fiber Bragg Grating pollution sensor is different to the close sensitivity close with ash of salt in filth;

Fiber Bragg Grating pollution sensor is the Fiber Bragg Grating that applies humidity-sensitive material, and the influence factor of sensor Bragg wavelength comprises humidity, temperature, salinity and ash content.

The Bragg wavelength of Fiber Bragg Grating compensation sensor is with the increase generation red shift of humidity, and red shift amplitude increases with the increase of humidity and temperature.

Fiber Bragg Grating pollution sensor

1), without filthy situation, Bragg wavelength red shift amplitude increases with the increase of humidity and temperature.

2) have filthy situation, filth comprises two kinds of salinity and ash contents

Temperature and humidity increases, the Bragg wavelength generation red shift of Fiber Bragg Grating pollution sensor.

Salinity increases, and the Bragg wavelength red shift amount of Fiber Bragg Grating pollution sensor reduces.Response time variation can be ignored.

Ash content increases, and the Bragg wavelength red shift amount of Fiber Bragg Grating pollution sensor reduces, and the response time increases.

Salt is close refers to the salt amount that is deposited on the given surface of insulator one (metal part and glueing material are not counted in this surface) result divided by this surface area.

Ash is close refer to be deposited on the given surface of insulator one (metal part and glueing material are not counted in this surface) can not be water-soluble material divided by the result of this surface area.

The Fiber Bragg Grating pollution sensor red shift of wavelength amount decrease degree that salinity causes with ash content is different, and the response time changes also different.

In different humidity-sensitive material coating thickness situations, the sensitivity difference of FBG pollution sensor.

The present invention utilizes filth to develop FBG pollution measurement sensor to the inhibiting effect of specific wet sensitive FBG.The principle of wet sensitive FBG is that humidity-sensitive material imbibition causes FBG strain to increase, and then makes the red shift of FBG Bragg wavelength.For example, by using specific coating and method of modifying to make humidity-sensitive material (polyimide) water absorptivity in the present invention be subject to the impact of filthy composition.This sensor is arranged on electric transmission line isolator, without filthy situation, and in the time that air humidity increases, the strained increase of sensor, wavelength generation red shift.When only salinity covers insulator and sensor, in the time that air humidity increases, due to salinity contact FBG pollution sensor, compare without filthy situation, FBG Bragg wavelength red shift amplitude reduces, but the response time does not change; When only ash content covers insulator and sensor, in the time that air humidity increases, due to ash content contact FBG pollution sensor, compare without filthy situation, the FBG Bragg wavelength red shift response time increases, and red shift amplitude is less than without filthy situation and is also less than salinity coverage condition.

Equal salt close or grey close under, along with the increase of humidity, the Bragg wavelength red shift amplitude increase of the FBG pollution sensor of developing.Under equal ash is close, along with the increase of humidity, the Bragg wavelength red shift response time of the FBG pollution sensor of developing reduces.And under equal humidity, along with salt is close and grey close increase, the Bragg wavelength red shift amplitude of the FBG pollution sensor of developing reduces.And under equal humidity, along with the close increase of ash, the Bragg wavelength red shift response time of the FBG pollution sensor of developing increases.In different humidity-sensitive material coating thickness situations, the sensitivity difference of FBG pollution sensor.

The computing formula of Fiber Bragg Grating compensation sensor temperature and humidity is:

$\left\{\begin{array}{c}{\mathrm{\λ}}_3={\mathrm{\α}}_{T3}T+{\mathrm{\α}}_{H3}H\\ {\mathrm{\λ}}_4={\mathrm{\α}}_{T4}T+{\mathrm{\α}}_{H4}H\end{array}\right.$

λ ₃for Fiber Bragg Grating compensation sensor applies the Bragg wavelength that humidity-sensitive material part obtains;

λ ₄for Fiber Bragg Grating compensation sensor does not apply the Bragg wavelength that humidity-sensitive material part obtains;

α _t3for Fiber Bragg Grating compensation sensor applies Bragg wavelength that humidity-sensitive material part the obtains sensitivity coefficient to temperature;

α _t4for Fiber Bragg Grating compensation sensor does not apply Bragg wavelength that humidity-sensitive material part the obtains sensitivity coefficient to temperature;

α _h3for Fiber Bragg Grating compensation sensor applies Bragg wavelength that humidity-sensitive material part the obtains sensitivity coefficient to humidity;

α _h4for Fiber Bragg Grating compensation sensor does not apply Bragg wavelength that humidity-sensitive material part the obtains sensitivity coefficient to humidity;

T is temperature;

H is humidity.

Close and the grey close computing formula of salt is:

$\left\{\begin{array}{c}{\mathrm{\λ}}_1={\mathrm{\α}}_{T1}T+{\mathrm{\α}}_{H1}H+{\mathrm{\α}}_{S1}S+{\mathrm{\α}}_{A1}A\\ {\mathrm{\λ}}_2={\mathrm{\α}}_{T2}T+{\mathrm{\α}}_{H2}H+{\mathrm{\α}}_{S2}S+{\mathrm{\α}}_{A2}A\end{array}\right.$

Wherein:

λ ₁it is the Bragg wavelength of the first Fiber Bragg Grating pollution sensor;

λ ₂it is the Bragg wavelength of the second Fiber Bragg Grating pollution sensor;

α _t1be that the Bragg wavelength of the first Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of temperature;

α _t2be that the Bragg wavelength of the second Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of temperature;

α _h1be that the Bragg wavelength of the first Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of humidity;

α _h2be that the Bragg wavelength of the second Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of humidity;

α _s1be that the Bragg wavelength of the first Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of salinity;

α _s2be that the Bragg wavelength of the second Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of salinity;

α _a1be that the Bragg wavelength of the first Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of gray scale;

α _a2be that the Bragg wavelength of the second Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of gray scale;

T is temperature;

H is humidity;

S is salinity;

A is gray scale.

The present invention contains " wet sensitive coating thickness-humidity-salt is close-ash is close-red shift amplitude-red shift response time " database, in measurement, utilize red shift amplitude and the red shift response time of FBG pollution sensor, obtain the close and grey close situation of the salt of measured point in conjunction with FBG compensation sensor measurement result and database.

In the present invention, FBG pollution sensor can be arranged on the insulator of different shaft towers, realizes the distributed measurement of power transmission line circuit filth on a large scale by wavelength-division multiplex and time division multiplexing mode.

Fig. 1 is Fiber Bragg Grating pollution sensor schematic diagram, and specific humidity-sensitive material 100 is coated in Fiber Bragg Grating 105 surfaces, and this sensor is arranged on electric transmission line isolator, without filthy situation, in the time that air humidity increases, the strained increase of sensor, wavelength generation red shift.When only salinity covers insulator and sensor, in the time that air humidity increases, due to salinity contact FBG pollution sensor, compare without filthy situation, FBG Bragg wavelength red shift amplitude reduces, but the response time does not change; When only ash content covers insulator and sensor, in the time that air humidity increases, due to ash content contact FBG pollution sensor, compare without filthy situation, the FBG Bragg wavelength red shift response time increases, and red shift amplitude is less than without filthy situation and is also less than salinity coverage condition.

Fig. 2 is Fiber Bragg Grating pollution sensor site layout project figure according to an embodiment of the invention, insulator 200 is for connecting wire 205 and cross-arm 210, the object of system of the present invention is the filth of measuring on insulator 200, Fiber Bragg Grating pollution sensor array (215) is arranged in insulator surface, draws optical fiber 220 be connected in terminal box 225 by first; Be arranged in Fiber Bragg Grating compensation sensor 235 in thermometer screen 230 for measures ambient humidity and temperature, draw optical fiber 240 by second and be connected in terminal box 225.Terminal box output optical cable 245 is connected with OPGW or ADSS, or is connected with OPPC by special insulator.Computing machine 255 is connected with Wavelength demodulation system 250 by wired or wireless mode; Wavelength demodulation system 250 is connected with fiber-optic bragg grating sensor with terminal box by OPGW optical, All Dielectric self-support ADSS, OPPC optical cable or armored optical cable.

Fig. 3 is partial data in " wet sensitive coating thickness-humidity-salt is close-ash is close-red shift amplitude-red shift response time " database, data show be in the close situation of different salt FBG Bragg wavelength with the variation of relative humidity, under equal humidity, along with the close increase of salt, the Bragg wavelength red shift amplitude of the FBG pollution sensor of developing reduces.Under equal salt is close, along with the increase of humidity, the Bragg wavelength red shift amplitude of the FBG pollution sensor of developing increases.

The above; only for preferably embodiment of the present invention, but protection scope of the present invention is not limited to this, is anyly familiar with in technical scope that those skilled in the art disclose in the present invention; the variation that can expect easily or replacement, within all should being encompassed in protection scope of the present invention.Therefore, protection scope of the present invention should be as the criterion with the protection domain of claim.

Claims (10)

1. a Fiber Bragg Grating transmission line of electricity contamination on-line monitoring system, is characterized in that this system comprises that computing machine, Wavelength demodulation system, terminal box, terminal box are exported optical cable, thermometer screen, first is drawn optical fiber, second and drawn optical fiber, Fiber Bragg Grating pollution sensor array and Fiber Bragg Grating compensation sensor;

Described Wavelength demodulation system comprises solar electrical energy generation module and wireless communication module;

Described computing machine is connected with Wavelength demodulation system; Wavelength demodulation system is exported optical cable by terminal box and is connected with terminal box; Terminal box is drawn optical fiber and second by first and is drawn optical fiber and be connected with Fiber Bragg Grating pollution sensor array and Fiber Bragg Grating compensation sensor respectively; Fiber Bragg Grating compensation sensor is placed in thermometer screen;

Described Fiber Bragg Grating pollution sensor array is made up of the first Fiber Bragg Grating pollution sensor and the second Fiber Bragg Grating pollution sensor, and the first Fiber Bragg Grating pollution sensor is the Fiber Bragg Grating that applies the first setting thickness humidity-sensitive material; The second Fiber Bragg Grating pollution sensor is the Fiber Bragg Grating that applies the second setting thickness humidity-sensitive material;

The half of described Fiber Bragg Grating compensation sensor is the Fiber Bragg Grating that applies the 3rd setting thickness humidity-sensitive material, second half of Fiber Bragg Grating compensation sensor be not for applying the Fiber Bragg Grating of humidity-sensitive material, and Fiber Bragg Grating compensation sensor adds moisture-inhibiting dust-proof sheath;

Described Wavelength demodulation system is for carrying out demodulation to the wavelength of Fiber Bragg Grating pollution sensor array and the collection of Fiber Bragg Grating compensation sensor;

It is close and grey close that described computing machine utilizes Wavelength demodulation system demodulation Bragg wavelength data out to calculate acquisition salt.

2. a kind of Fiber Bragg Grating transmission line of electricity contamination on-line monitoring system according to claim 1, is characterized in that described terminal box output optical cable is OPGW optical, All Dielectric self-support ADSS, OPPC optical cable or armored optical cable.

3. a kind of Fiber Bragg Grating transmission line of electricity contamination on-line monitoring system according to claim 1, is characterized in that the connected mode of described the first Fiber Bragg Grating pollution sensor and the second Fiber Bragg Grating pollution sensor is serial or parallel connection.

4. a kind of Fiber Bragg Grating transmission line of electricity contamination on-line monitoring system according to claim 1, is characterized in that described humidity-sensitive material is polyimide or hydrogel.

5. a kind of Fiber Bragg Grating transmission line of electricity contamination on-line monitoring system according to claim 1, is characterized in that described computing machine is connected by netting twine or wireless communication module with Wavelength demodulation system.

6. a kind of Fiber Bragg Grating transmission line of electricity contamination on-line monitoring system according to claim 5, while it is characterized in that described computing machine is connected by netting twine with Wavelength demodulation system, Wavelength demodulation system passes through mains-supplied.

7. a kind of Fiber Bragg Grating transmission line of electricity contamination on-line monitoring system according to claim 5, while it is characterized in that described computing machine is connected by wireless communication module with Wavelength demodulation system, Wavelength demodulation system is by solar electrical energy generation module for power supply.

8. system is carried out the method for the filthy on-line monitoring of transmission line of electricity according to claim 1, it is characterized in that the method comprises the following steps:

Step 1: the assigned address that described terminal box, thermometer screen, Fiber Bragg Grating pollution sensor array and Fiber Bragg Grating compensation sensor is placed in to power transmission line;

Step 2: by the data of described Fiber Bragg Grating pollution sensor array and the collection of Fiber Bragg Grating compensation sensor, be sent to described Wavelength demodulation system by described terminal box;

Step 3: demodulation Bragg wavelength data are out sent to described computing machine by described Wavelength demodulation system;

Step 4: it is close and grey close that described computing machine calculates salt according to demodulation Bragg wavelength data out.

9. the method for the filthy on-line monitoring of a kind of transmission line of electricity according to claim 8, is characterized in that the computing formula of described Fiber Bragg Grating compensation sensor temperature and humidity is:

$\left\{\begin{array}{c}{\mathrm{\λ}}_3={\mathrm{\α}}_{T3}T+{\mathrm{\α}}_{H3}H\\ {\mathrm{\λ}}_4={\mathrm{\α}}_{T4}T+{\mathrm{\α}}_{H4}H\end{array}\right.$

λ ₃for Fiber Bragg Grating compensation sensor applies the Bragg wavelength that humidity-sensitive material part obtains;

λ ₄for Fiber Bragg Grating compensation sensor does not apply the Bragg wavelength that humidity-sensitive material part obtains;

α _t3for Fiber Bragg Grating compensation sensor applies Bragg wavelength that humidity-sensitive material part the obtains sensitivity coefficient to temperature;

α _t4for Fiber Bragg Grating compensation sensor does not apply Bragg wavelength that humidity-sensitive material part the obtains sensitivity coefficient to temperature;

α _h3for Fiber Bragg Grating compensation sensor applies Bragg wavelength that humidity-sensitive material part the obtains sensitivity coefficient to humidity;

α _h4for Fiber Bragg Grating compensation sensor does not apply Bragg wavelength that humidity-sensitive material part the obtains sensitivity coefficient to humidity;

T is temperature;

H is humidity.

10. the method for the filthy on-line monitoring of a kind of transmission line of electricity according to claim 9, is characterized in that the close and grey close computing formula of described salt is:

$\left\{\begin{array}{c}{\mathrm{\λ}}_1={\mathrm{\α}}_{T1}T+{\mathrm{\α}}_{H1}H+{\mathrm{\α}}_{S1}S+{\mathrm{\α}}_{A1}A\\ {\mathrm{\λ}}_2={\mathrm{\α}}_{T2}T+{\mathrm{\α}}_{H2}H+{\mathrm{\α}}_{S2}S+{\mathrm{\α}}_{A2}A\end{array}\right.$

Wherein:

λ ₁it is the Bragg wavelength of the first Fiber Bragg Grating pollution sensor;

λ ₂it is the Bragg wavelength of the second Fiber Bragg Grating pollution sensor;

α _t1be that the Bragg wavelength of the first Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of temperature;

α _t2be that the Bragg wavelength of the second Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of temperature;

α _h1be that the Bragg wavelength of the first Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of humidity;

α _h2be that the Bragg wavelength of the second Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of humidity;

α _s1be that the Bragg wavelength of the first Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of salinity;

α _s2be that the Bragg wavelength of the second Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of salinity;

α _a1be that the Bragg wavelength of the first Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of gray scale;

α _a2be that the Bragg wavelength of the second Fiber Bragg Grating pollution sensor is to the sensitivity coefficient of gray scale;

S is salinity;

A is gray scale.

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