CN101556195B - Real-time monitoring method of ice coated on overhead transmission line conductor and system - Google Patents

Abstract

The invention relates to the field of the monitoring of a transmission line conductor, in particular to a real-time monitoring method of ice coated on an overhead transmission line conductor and a system thereof. The method comprises the following steps of: firstly, arranging tilt-temperature monitoring devices on each line conductor so as to monitor the suspension point tilt and the conductor temperature of line conductors in real time; secondly, arranging deviation angle-wind deflection angle monitoring devices on each suspended insulator string so as to monitor the deviation angles of the suspended insulator strings along the conductor direction and the wind deflection angles vertical to the conductor direction in real time; and calculating the ice coating comprehensive load and the icecoating thickness of each line conductor in real time through monitoring the suspension point tilt and the conductor temperature of the line conductors and the deviation angles of the suspended insulator strings in real time. The method has the beneficial effects that not only the ice coating thickness of the conductor can be measured, but also the comprehensive load of the ice-coated conductor can be measured, furthermore, the measure is reasonable and correct, the algorithm is simple, and the result is accurate, and the method can be applied to the comprehensive load calculation of the strain section of the lines, on which ice is evenly coated or unevenly coated.

Description

Real-time monitoring method of ice coated on overhead transmission line conductor and system

Technical field

The present invention relates to the monitoring field of transmission line wire, relate in particular to real-time monitoring method of ice coated on overhead transmission line conductor and system, be specially adapted to early warning, monitoring and the prevention and control field of powerline ice-covering.

Background technology

China's weather environment vast in territory is changeable, it is one of more country of powerline ice-covering in the world, at the beginning of 2005 and 2008 2 times big ice and snow hazard weathers cause serious circuit icing, tripping operation, broken string, fall accident such as tower, bring heavy losses for national economy and industrial or agricultural, people's lives electricity consumption.The main cause of these 2 ice and snow disasters be for many years one meet on a large scale, long-time low temperature sleet frost climate, but reflect that also China's electrical network resists the scarce capacity of bad weather condition, lack the means of comprehensive load situation after grasping the circuit icing in the very first time.

The broken string whether the circuit icing can cause, the key of accidents such as tower of falling are: whether coated by ice of overhead power transmission line lead comprehensive load exceeds the stress that lead or shaft tower can bear, the purpose of early warning, monitoring mainly is to obtain icing lead comprehensive load accurately, judge whether to take measures, with avoid broken string, the accident accident such as tower of falling takes place.

The monitoring of past to the powerline ice-covering situation mainly is to lean on circuit operations staff's field observation measurement to realize, but there is following shortcoming in the mode that artificial field observation is measured: one, cost of labor is huge, and efficiency is low; Two, naked eyes can only be observed the surface condition of powerline ice-covering, can only be range estimations, and the data of accurate science can not be provided, and also can't calculate coated by ice of overhead power transmission line lead comprehensive load.

Someone once imagined and utilizes video equipment to monitor, but often the local temperature of powerline ice-covering is low, the wetness height, video camera is general cisco unity malfunction under such environment, the image that transmission is returned is very fuzzy, if use expensive military infrared camera, can transmit distinct image, but this cost of labor that also can only overcome artificial field observation measurement existence is huge, the shortcoming that efficiency is low, distinct image can not provide the circuit ice coating wire comprehensive load data of accurate science again.Along with the national economy fast development, the distribution of ultra-high-tension power transmission line is more and more wider, the destruction of earth environment, meteorological changeful, power system monitoring department seek forwardly a kind of can be under inclement weather environment such as high-voltage electric field and high low temperature reliably working, can realize the method and system of the real-time precise monitoring of circuit icing.

Summary of the invention

The object of the present invention is to provide real-time monitoring method of ice coated on overhead transmission line conductor, this method is according to the line wire hitch point inclination angle of The real time measure, conductor temperature, suspension insulator deviation angle and essential parameter of circuit are determined and computational scheme ice coating wire comprehensive load and wire icing thickness, this method is reasonable in theory, correctly, algorithm is simple, the result is accurate, and can be applicable to the calculating of interior evenly icing of circuit strain section and non-homogeneous icing, the power department early warning is satisfied in the convenient monitoring that has realized exactly the coated by ice of overhead power transmission line lead fully, the requirement of monitoring.

Another object of the present invention is to provide the ice coated on overhead transmission line conductor real-time monitoring system, this system is the deviation angle of hitch point inclination angle, conductor temperature and the suspension insulator of measuring circuit lead in real time, calculate in real time to realize above-mentioned ice coating wire comprehensive load, monitoring system provided by the invention adopts multinomial new technology, can be under inclement weather environment such as high-voltage electric field and high low temperature reliably working, provide master data for realizing monitoring in real time of circuit icing and calculating.

The present invention achieves the above object by the following technical programs:

Real-time monitoring method of ice coated on overhead transmission line conductor comprises the steps: 1) inclination angle-device for detecting temperature is arranged on each grade line wire, be used for the hitch point inclination angle and the conductor temperature of real-time measuring circuit lead; 2) deviation angle-angle of wind deflection monitoring device is arranged on each suspension insulator, is used for measuring in real time suspension insulator along lead direction deviation angle and vertical wires direction angle of wind deflection; 3) the i shelves lead hitch point tiltangle of surveying according to inclination angle-device for detecting temperature _i(°),

Calculate:

I represents i shelves in the circuit strain section in the formula; l _iBe span (m); h _iBeing the two hitch point discrepancy in elevation (m), for just, is negative when lower than the other end when hitch point is higher than the other end;

For height difference angle (°); H _iThe Horizontal Tension of lead (N) during for ice coating state; w _iThe load of lead unit length (N/m) during for ice coating state;

4) vertical deviation angle according to the i shelves suspension insulator of deviation angle-angle of wind deflection monitoring device actual measurement is υ _i(°), i-1 shelves insulator chain vertical deviation angle is υ _(i-1)(°), calculate i shelves span increment Delta l _i(m):

Δl _i＝L _Ji×sinυ _i-L _J(i-1)×sinυ _(i-1)

L in the formula _Ji, L _{J (i-1)}Be respectively i, i-1 shelves insulator chain length (m);

5) the i shelves conductor temperature t that surveys according to inclination angle-device for detecting temperature _i(℃), i shelves lead Horizontal Tension H under the result of calculation of step 3), step 4) and the lead Parameter Calculation ice coating state _i(N):

E is the final elasticity coefficient (N/mm of lead in the formula ²); γ is the temperature line expansion coefficient (1/ ℃) of lead; S is the sectional area (mm of a lead ²); H _m, w _m, t _mThe temperature of the load (N/m) of the Horizontal Tension (N) of lead, lead unit length and lead when being respectively design or stringing operating mode (℃);

6) according to the result of calculation of step 5) and known parameter, the comprehensive load w of i shelves lead in the time of can calculating the wire icing state _i(N/m):

7), can calculate the ice covering thickness b of i shelves lead according to the result of calculation of step 6) _i(mm):

${\mathrm{<figure-callout\; id="2"\; label="w\; i"\; filenames="H2009100971847E00011.png"\; state="\{\{state\}\}">w</figure-callout>}}_i^{}={[9.80665q+0.027728(b_i+D)]}^2+{[{0.625\mathrm{\&alpha;\&mu;}}_{\mathrm{sc}}{\mathrm{\&beta;}}_c(D+{2b}_i){\left(k_{h}v\right)}^2\&times;{\sin }^2\mathrm{\&theta;}\&times;{10}^{-3}]}^2$

V is actual measurement wind speed (m/s) in the formula; θ be wind direction and electric wire axially between angle (°); H is electric wire average height (m); D is electric wire external diameter (mm); μ sc is the wind carrier shape coefficient of lead, establishes μ sc=1.2 herein; α is a uneven factor of wind speed, according to v size get different value; β c is that wind carries the adjustment coefficient, according to v size get different value; Following formula is quadratic equation with one unknown AX ²+ BX+C=0 can solve bi.

Wind speed v (m/s)	v＜20	?20≤v＜30	?30≤v＜35	v≥35
					α	1.0	?0.85	?0.75	0.7
βc	1.0	?1.1	?1.2	1.3

$K_h={\left(\frac{h}{h_s}\right)}^{0.16}$

Following formula is quadratic equation with one unknown AX ²+ BX+C=0, available general formula is found the solution.

The ice coated on overhead transmission line conductor real-time monitoring system comprises inclination angle-device for detecting temperature, deviation angle-angle of wind deflection monitoring device, the supervisory system main frame; Described inclination angle-device for detecting temperature is arranged on each grade line wire, and described deviation angle-angle of wind deflection monitoring device is arranged on each suspension insulator, and described supervisory system main frame is located at scene or Surveillance center; Deviation angle-angle of wind deflection monitoring device is connected with inclination angle-device for detecting temperature, inclination angle-device for detecting temperature and monitoring host computer wireless connections.

Described inclination angle-device for detecting temperature, inside comprise with lower module: current transformer, power supply adjust module, inclination angle sampling module, temperature sampling module, current sample module, communication module, main control module MCU; Current transformer by with the direct coupling of line wire, be used for providing power supply, and handle the early stage of making alternating current to inclination angle-device for detecting temperature; Inclination angle sampling module, temperature sampling module, current sample module, communication module are connected with main control module MCU respectively, and the power supply module of adjusting is used to finish the voltage stabilizing function of inclination angle-device for detecting temperature operating voltage; The inclination angle sampling module is used for lead hitch point obliquity information is changed into the digital quantity that can be read by main control module MCU, exports main control module MCU to; The temperature sampling module is used for conductor temperature information is changed into the digital quantity that can be read by main control module MCU, exports main control module MCU to; The current sample module is used for lead alternating current information is changed into the digital quantity that can be read by main control module MCU, exports main control module MCU to; Main control module MCU is used to read, handle the digital quantity of inclination angle, temperature and the electric current of inclination angle-device for detecting temperature, finish correlation computations and storage data, finish the processing of supervisory system host command, communication module is used to finish the data that main control module MCU sends and the transmitting-receiving task of steering order, in the RF mode all information is mail to the supervisory system main frame.

Described deviation angle-angle of wind deflection monitoring device inside is twin shaft digital angle sensor assembly, the output digital signal is received the main control module MCU of the monitoring device of above-mentioned inclination angle-temperature by cable, main control module MCU control communication module mails to the supervisory system main frame in the RF mode with information.

Beneficial effect of the present invention: powerline ice-covering monitoring in real time is a new problem, the present invention adopts the real-time monitoring device of special overhead transmission line hitch point lead inclination angle-temperature and suspension insulator deviation angle to come real-time measuring circuit lead hitch point inclination angle, conductor temperature and suspension insulator deviation angle, and propose with lead hitch point inclination angle, conductor temperature and suspension insulator deviation angle are come the method for real-time computational scheme wire icing comprehensive load, the effect that adopts method of the present invention is the ice covering thickness that is not only can measure lead, even more important is the comprehensive load of measuring ice coating wire, and measure rationally, correctly, algorithm is simple, the result is accurate, the comprehensive load that can be applicable to interior evenly icing of circuit strain section and non-homogeneous icing is calculated, so just can be when comprehensive load exceed the stress that lead or shaft tower can bear, take measures early, avoid the tripping operation that causes because of the circuit icing, broken string, fall accidents such as tower, give national economy and industrial or agricultural, the people's lives electricity consumption brings heavy losses, the power department early warning is satisfied in the convenient monitoring that has realized exactly the coated by ice of overhead power transmission line lead, the requirement of monitoring.

Ice coated on overhead transmission line conductor real-time monitoring system provided by the invention, energy is the hitch point inclination angle of measuring circuit lead in real time, the deviation angle of conductor temperature and suspension insulator, calculate in real time to realize above-mentioned ice coating wire comprehensive load, monitoring system provided by the invention adopts multinomial new technology, can be under inclement weather environment such as high-voltage electric field and high low temperature reliably working, for realizing that monitoring in real time of circuit icing and calculating provide master data, can realize the circuit icing is formed, development, the overall process that worsens is monitored in real time, is that domestic function ratio is more complete, practical, effective comprehensive load real-time monitoring system.

Description of drawings

Fig. 1 is the scheme of installation of ice coated on overhead transmission line conductor real-time monitoring system;

Fig. 2 is an ice coated on overhead transmission line conductor real-time monitoring system principle assumption diagram;

Fig. 3 is the synoptic diagram of the strain section of the inhomogeneous icing of each grade lead;

Fig. 4 is lead inclination angle-device for detecting temperature theory diagram;

Embodiment

The present invention is described further below in conjunction with specific embodiment, but protection scope of the present invention is not limited in this:

Embodiment 1: with certain 500kV circuit ice coating wire one strain section is example, the 4th grade (#147-#148) wherein and the 5th grade (#148-#149), wire type is 4*LGJ-630/45, the 4th grade span is that 352m, the discrepancy in elevation are that 39.0m, installation sag are 9.27m, the 5th grade span is that 437m, the discrepancy in elevation are that 1.0m, installation sag are 14.20m, and environment temperature is that 0 ℃, Horizontal Tension are 33950N during installation.The suspension insulator string length is 5.5m, and weight is 1960N.

This lead basic parameter is: calculate cross section 666.55mm ²External diameter 33.60mm; Unit mass 2.06kg/m; Elasticity coefficient 63000N/mm ²1/ ℃ of linear expansion coefficient 20.9x10-6.

The ice coated on overhead transmission line conductor real-time monitoring system comprises inclination angle-device for detecting temperature 1, deviation angle-angle of wind deflection monitoring device 2, supervisory system main frame 3; Described inclination angle-device for detecting temperature 1 is arranged on each grade line wire, and described deviation angle-angle of wind deflection monitoring device 2 is arranged on each suspension insulator, and described supervisory system main frame 3 is located at Surveillance center; Deviation angle-angle of wind deflection monitoring device 2 is connected with inclination angle-device for detecting temperature 1, inclination angle-device for detecting temperature 1 and monitoring host computer wireless connections.

On the 4th grade of lead and the 5th grade of lead inclination angle-device for detecting temperature 1 is housed, inside comprises with lower module: current transformer; The power supply module of adjusting; The inclination angle sampling module; The temperature sampling module; The current sample module; Communication module; Main control module MCU; Current transformer by with the direct coupling of line wire, power supply is provided for inclination angle-device for detecting temperature, and handle the early stage of making alternating current; Inclination angle sampling module, temperature sampling module, current sample module, communication module are connected with main control module MCU respectively, and the power supply module of adjusting is used to finish the voltage stabilizing function of inclination angle-device for detecting temperature operating voltage; The inclination angle sampling module is used for lead hitch point obliquity information is changed into the digital quantity that can be read by main control module MCU, exports main control module MCU to; The temperature sampling module is used for conductor temperature information is changed into the digital quantity that can be read by main control module MCU, exports main control module MCU to; The current sample module is used for lead alternating current information is changed into the digital quantity that can be read by main control module MCU, exports main control module MCU to; Main control module MCU is used to read, handle the digital quantity of inclination angle, temperature and the electric current of inclination angle-device for detecting temperature, and the deviation angle sent here of the deviation angle monitoring device 2 of suspension insulator and the digital quantity of angle of wind deflection, finish correlation computations and storage data, finish the processing of supervisory system main frame 3 instructions; Communication module is used to finish the data that main control module MCU sends and the transmitting-receiving task of steering order, in the RF mode all information is mail to supervisory system main frame 3, and described supervisory system main frame 3 is installed in 3 Surveillance center; Inclination angle-device for detecting temperature 1 is installed in a kind of spherical housing, this shell patent applied for, patent name: a kind of shell of on-line monitoring device for transmission line, number of patent application: 2005100493902, this shell is fastened on the lead by upper and lower spheroid.Deviation angle-2 ones of angle of wind deflection monitoring devices are twin shaft digital angle sensor assembly, and the output digital signal is received the main control module MCU main control module of the monitoring device of above-mentioned inclination angle-temperature by cable.

Each grade lead is inhomogeneous icing in the strain section, and the prevailing circumstances temperature is-5 ℃, and is calm.The deviation angle that records the #1 device in real time is 26.89 °, and the deviation angle of #2 device is 20.39 °, and the deviation angle of #3 device is 7.80 °, the inclination angle of #4 device is 2.737 °, the inclination angle of #5 device is 15.096 °, and the inclination angle of #6 device is 11.056 °, and the inclination angle of #7 device is 11.309 °.

Calculate the 4th grade of ice coating wire comprehensive load:

1) according to the inclination angle and the known parameters of #4 device, can calculate:

2) according to the deviation angle of #1, #2 device, can calculate:

Δl ₄＝L _J4×sinυ ₄-L _J3×sinυ ₃＝5.5×sin20.39-5.5×sin26.89＝-0.5713

3), can calculate according to the aforementioned calculation result:

$=\frac{(-0.5713)\&times;63000\&times;666.55\&times;{\cos }^{3}6.3232}{352}\&times;(1+\frac{{352}^2}{8}\&times;{0.0008981}^2)$

$-\frac{{352}^2\&times;63000\&times;666.55\&times;{\cos }^{3}6.3232}{24}\&times;[{\left(\frac{2.06\&times;9.80665}{33950}\right)}^2-{0.0008981}^2]$

$-20.9\&times;{10}^{-6}\&times;63000\&times;666.55\&times;\cos 6.3232\&times;(-5-0)+33950$

$=66926.27$

4) with above-mentioned result of calculation and known parameter, the comprehensive load w of the 4th grade of lead in the time of can calculating the wire icing state ₄(N/m):

Can calculate:

5) according to w ₄Result of calculation, and lead is from the load w of gravitational unit ₁=9.80665q (N/m)

Q is linear mass (kg/km) in the formula.

If the icing of all kinds and different section profile all convert for density be 0.9g/cm ³Circular glaze section.When oneself knows wire diameter D and ice covering thickness b, its unit length ice load w ₂(N/m) be

${\mathrm{<figure-callout\; id="2"\; label="w"\; filenames="H2009100971847E00011.png"\; state="\{\{state\}\}">w</figure-callout>}}_2=\frac{0.9\mathrm{\&pi;}{g}_n}{4}[{(D+2b)}^2-D^2]\&times;{10}^{-3}=0.027728b(b+D)---\left(1\right)$

Have under the wind state, during wire icing perpendicular to the unit level wind load w of wire axis ₅(N/m) be calculated as follows

w ₅＝0.625αμ _scβ _c(D+2b)(k _hv) ²×sin ²θ×10 ^-3 (2)

This moment lead comprehensive load w ₇(N/m) add the vertical load w that icing produces for deadweight ₃Horizontal loading w with the wind-force generation ₅Square, promptly

${w_7}^2=w_3^2+w_5^2---\left(3\right)$

To can get after formula (1), formula (2) the substitution formula (3)

$w_7^2={[9.80665q+0.027728(b+D)]}^2+{[{0.625\mathrm{\&alpha;\&mu;}}_{\mathrm{sc}}{\mathrm{\&beta;}}_c(D+2b){\left(k_{h}v\right)}^2\&times;{\sin }^2\mathrm{\&theta;}\&times;{10}^{-3}]}^2---\left(4\right)$

In the formula

V is actual measurement wind speed (m/s),

θ be wind direction and electric wire axially between angle (°).

H is electric wire average height (m),

D is electric wire external diameter (mm),

B is electric wire ice covering thickness (mm),

μ sc is the wind carrier shape coefficient of lead, establishes μ sc=1.2 herein;

γ is a uneven factor of wind speed, according to v size get different value;

β c is that wind carries the adjustment coefficient, according to v size get different value;

μsc＝1.2

$K_h={\left(\frac{h}{h_s}\right)}^{0.16}$

110-330kV circuit h _s=15m, 500kV circuit h _s=20m

So having under the wind state, obtaining the comprehensive load w of i shelves lead _7iAfter, other coefficient is selected for use by above-mentioned, can calculate the ice covering thickness b of i shelves lead _iThis equation is a quadratic equation with one unknown, AX2+BX+C=0, and available general formula is found the solution.

V=0 formula (12) is reduced to when calm

w ₇＝9.80665q+0.027728(b+D)

Promptly

$b_i=\frac{-0.027728D\&PlusMinus;\sqrt{{\left(0.027728D\right)}^2+4\&times;0.027728\&times;(w_i-9.80665q)}}{2\&times;0.027728}$

Annotate: when in the strain section during the even icing of each grade lead, desirable insulator chain vertical deviation angle υ _i=0 °, span variation delta l _i=0, calculate with said method, its result is identical with the result of calculation of using state equation.

Can calculate the ice covering thickness b of i shelves lead _i(mm):

${\mathrm{<figure-callout\; id="2"\; label="w\; i"\; filenames="H2009100971847E00011.png"\; state="\{\{state\}\}">w</figure-callout>}}_i^{}={[9.80665q+0.027728(b_i+D)]}^2+{[{0.625\mathrm{\&alpha;\&mu;}}_{\mathrm{sc}}{\mathrm{\&beta;}}_c(D+{2b}_i){\left(k_{h}v\right)}^2\&times;{\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="H2009100971847E00011.png"\; state="\{\{state\}\}">sin</figure-callout>}}^2\mathrm{\&theta;}\&times;{10}^{-3}]}^2$

Calculate:

$b_4=\frac{-0.027728D\&PlusMinus;\sqrt{{\left(0.027728D\right)}^2+4\&times;0.027728\&times;(w_4-w_1)}}{2\&times;0.027728}$

$=\frac{-0.027728\&times;33.6+\sqrt{{(0.027728\&times;33.6)}^2+4\&times;0.027728\&times;(59.943-2.06\&times;9.80665)}}{2\&times;0.027728}$

$=24.59$

The ice covering thickness that can calculate the 4th grade of lead under the windless condition according to the lead inclination angle and the suspension insulator deviation angle of actual measurement is 24.59mm.

Can calculate the icing of the 5th grade of lead according to the deviation angle of the inclination angle of #6 device and #2, #3 device with example, w5/H5=0.000905; H5=79622.02; W5=72.0383; B5=29.55 is so the ice covering thickness of the 5th grade of lead is 29.55mm under the windless condition.

In practice, find that the circuit icing is a progressive process, be fit to from meteorological condition, icing forms, the ice sheet thickening, circuit stress, sag increase, and lead to a disaster until exceeding the stress that lead or shaft tower can bear, and this process takes several hours or several days.We also can install small-sized weather station, circuit video supervisory device additional in the monitoring system of foregoing description, can realize the real time comprehensive monitoring to the circuit icing.

Can understand near the variation of the weather environment circuit from the data of small-sized weather station, the meteorological condition of icing whether occur forming: air humidity big (90～95%), the temperature (0～-5 ℃) that is fit to and make the wind speed that water droplet moves (＞1m/s).Can freeze on the lead, whether conductor temperature be lower than 0 ℃.Observe the situation of sleet landing on the circuit again from the circuit video-unit, whether occurred icing on insulator chain and the lead, the icing development trend.Simultaneously according to the lead inclination angle of actual measurement and the variation of insulator chain deviation angle, determine the thickness of the wire icing of the situation of icing and calculating.If at continuous several days ice and snow weather, small-sized weather station and circuit video-unit are buried cisco unity malfunction by heavy snow, but lead inclination angle-temperature measuring equipment still can normally provide data, even line tripping, the inner reserve battery of device can guarantee that still work is more than 48 hours, up to the serious icing of circuit, broken string, the tower that falls, inclination data generation transition exceeds measurement range.So powerline ice-covering real time comprehensive monitoring system can realize the overall process that the circuit icing forms, develops, worsens is monitored in real time, be more complete, practical, the effective icing real-time monitoring system of domestic function ratio.

Inclination angle-the temperature measuring equipment of the present invention's proposition also can be used for the real-time monitoring of transmission line dynamic current-carrying capacity and the real-time monitoring of lead sag in addition, and insulator chain deviation angle measurement mechanism also can be used for the real-time monitoring of transmission line of electricity windage yaw.Conductor temperature and current monitoring data can provide the control foundation when adjusting line load or alternating current-direct current short circuit ice-melt.

Above described be specific embodiments of the invention and the know-why used, if the change of doing according to conception of the present invention, when the function that it produced does not exceed spiritual that instructions and accompanying drawing contain yet, must belong to protection scope of the present invention.

Claims (3)

1. real-time monitoring method of ice coated on overhead transmission line conductor is characterized in that comprising the steps: 1) inclination angle-device for detecting temperature is arranged on each grade line wire, be used for the hitch point inclination angle and the conductor temperature of real-time measuring circuit lead; 2) deviation angle-angle of wind deflection monitoring device is arranged on each suspension insulator, is used for measuring in real time suspension insulator along lead direction deviation angle and vertical wires direction angle of wind deflection; 3) the i shelves lead hitch point tiltangle of surveying according to inclination angle-device for detecting temperature _i°,

Calculate:

I represents i shelves in the circuit strain section in the formula; Li is a span, and unit is m; h _iBe the two hitch point discrepancy in elevation, unit is m, for just, is negative when lower than the other end when hitch point is higher than the other end;

Be height difference angle, unit is °; H _iThe Horizontal Tension of lead during for ice coating state, unit is N; w _iThe load of lead unit length during for ice coating state, unit are N/m;

4) vertical deviation angle according to the i shelves suspension insulator of deviation angle-angle of wind deflection monitoring device actual measurement is υ _i°, i-1 shelves insulator chain vertical deviation angle is υ _(i-1)°, calculate i shelves span increment Delta l _i, unit is m:

${\mathrm{\&Delta;l}}_i=L_{\mathrm{Ji}}\&times;\sin {\mathrm{\&upsi;}}_i-L_{J(i-1)}\&times;\sin {\mathrm{\&upsi;}}_{(i-1)}$

L in the formula _Ji, L _{J (i-1)}Be respectively i, i-1 shelves insulator chain length, unit is m;

5) the i shelves conductor temperature t that surveys according to inclination angle-device for detecting temperature _i, unit is ℃, i shelves lead Horizontal Tension H under the result of calculation of step 3), step 4) and the lead Parameter Calculation ice coating state _i, unit is N:

E is the final elasticity coefficient of lead in the formula, and unit is N/mm ²γ is the temperature line expansion coefficient of lead, and unit is 1/ ℃; S is the sectional area of a lead, and unit is mm ²H _m, w _m, t _mBe respectively design or the Horizontal Tension of lead during the stringing operating mode, unit is the load of N, lead unit length, and unit is the temperature of N/m and lead, and unit is ℃;

6) according to the result of calculation of step 5) and known parameter, the comprehensive load w of i shelves lead in the time of can calculating the wire icing state _i, unit is N/m:

2. real-time monitoring method of ice coated on overhead transmission line conductor according to claim 1, its feature are at son, and according to the result of calculation of step 6), establishing the ice conversion is 0.9g/cm for density q ³Circular glaze section, calculate the ice covering thickness bi of i shelves lead, unit is mm:

$w_i^2={[9.80665q+0.027728(b_i+D)]}^2+{[0.625{\mathrm{\&alpha;\&mu;}}_{\mathrm{sc}}{\mathrm{\&beta;}}_c(D+{2b}_i){\left(k_{h}v\right)}^2\&times;{\sin }^2\mathrm{\&theta;}\&times;{10}^{-3}]}^2$

V is the actual measurement wind speed in the formula, and unit is m/s; θ be wind direction and electric wire axially between angle, unit is °; H is the electric wire average height, and unit is m; D is the electric wire external diameter, and unit is mm; μ sc is the wind carrier shape coefficient of lead, establishes μ sc=1.2 herein; α is a uneven factor of wind speed, according to v size get different value; β c is that wind carries the adjustment coefficient, according to v size get different value;

Following formula is quadratic equation with one unknown AX ²+ BX+C=0 can solve bi.

3. the ice coated on overhead transmission line conductor real-time monitoring system is characterized in that comprising inclination angle-device for detecting temperature, deviation angle-angle of wind deflection monitoring device, the supervisory system main frame; Described inclination angle-device for detecting temperature is arranged on each grade line wire, and described deviation angle-angle of wind deflection monitoring device is arranged on each suspension insulator, and described supervisory system main frame is located at scene or Surveillance center; Deviation angle-angle of wind deflection monitoring device is connected with inclination angle-device for detecting temperature, inclination angle-device for detecting temperature and monitoring host computer wireless connections; Described inclination angle-device for detecting temperature, inside comprise with lower module: current transformer, power supply adjust module, inclination angle sampling module, temperature sampling module, current sample module, communication module, main control module MCU; Current transformer by with the direct coupling of line wire, be used for providing power supply, and handle the early stage of making alternating current to inclination angle-device for detecting temperature; Inclination angle sampling module, temperature sampling module, current sample module, communication module are connected with main control module MCU respectively, and the power supply module of adjusting is used to finish the voltage stabilizing function of inclination angle-device for detecting temperature operating voltage; The inclination angle sampling module is used for lead hitch point obliquity information is changed into the digital quantity that can be read by main control module MCU, exports main control module MCU to; The temperature sampling module is used for conductor temperature information is changed into the digital quantity that can be read by main control module MCU, exports main control module MCU to; The current sample module is used for lead alternating current information is changed into the digital quantity that can be read by main control module MCU, exports main control module MCU to; Main control module MCU is used to read, handle the digital quantity of inclination angle, temperature and the electric current of inclination angle-device for detecting temperature, finish correlation computations and storage data, finish the processing of supervisory system host command, communication module is used to finish the data that main control module MCU sends and the transmitting-receiving task of steering order, in the RF mode all information is mail to the supervisory system main frame; Described deviation angle-angle of wind deflection monitoring device inside is twin shaft digital angle sensor assembly, the output digital signal is received the main control module MCU of the monitoring device of above-mentioned inclination angle-temperature by cable, main control module MCU control communication module mails to the supervisory system main frame in the RF mode with information.

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