CN105510725A - Self-adaptive determining method for voltage grade of high-voltage line - Google Patents

Abstract

The invention belongs to the field of electric power transmission safety, and provides a self-adaptive determining method for voltage grade of a high-voltage line. The self-adaptive determining method comprises the steps of recording a sampling value every advancing for a distance [mu], and when the advancing distance is larger than an integral window length m[mu], calculating an integral value [epsilon] in the integral window; then sliding the integral window, updating the integral value every advancing for an integral window sliding distance w[mu], comparing a latest integral value with a former integral value, if the latest integral value is larger than the former integral value, continuing measurement and upgrading, and if the latest integral value is smaller than the former integral value, determining the former integral value is the maximal integral value [epsilon]max; and finally respectively comparing the maximal integral value [epsilon]max with the maximal integral value which corresponds with each voltage grade which is prestored in the system, finding out a prestored value which is most approximate to the [epsilon]max, and determining the voltage grade which corresponds with the prestored value that is most approximate to the [epsilon]max as the current voltage grade. The self-adaptive determining method can realize self-adaptive determination for the voltage grade of the high-voltage line and provides effective safety insurance for the working environment of an electrician.

Description

Hi-line electric pressure self-adaptation method of discrimination

Technical field

The invention belongs to electric power transfer security fields, relate to a kind of method utilizing Electric Field Distribution feature decision hi-line electric pressure near hv transmission line.

Background technology

Along with the high speed development of national economy, the demand of all trades and professions to electric power is increasing, and also more and more higher to the quality requirements of power supply department supply electric power, therefore the construction of power industry and service seem particularly important; Safe and reliable electric power supply is of great significance guarantee social stability and tool of promoting economic development.The safe and reliable operation of electric power facility be unable to do without the work of power worker, and they need to build, rush to repair electric power facility often, or even when equipment live; Hi-line is with very high voltage, and too near the danger having electric shock, but power worker is operationally but among this danger often.For the safety guarantee of power worker's construction, China has formulated strict industry guideline and behavioral standard, but in the process of construction, often still can cause the generation of accident because of carelessness.Because different electric pressure hi-line minimum safe distance is different, so knowing electric pressure is the first step ensureing power worker's safety, the automatic discrimination realizing high voltage transmission line electric pressure from the aspect of technology is highly significant for raising construction safety.

Electric power source self generator, due to the restriction of generator insulating condition, the ceiling voltage of generator is generally at below 22kV.In order to reduce the electric energy loss of transmission line of electricity, increase the distance of electric energy conveying, the electricity that generating plant sends needs could access transmission system usually after boosting.After electric power is transported to distribution substation, need again to become different voltage to flow to final power consumer high-tension electricity step-down according to the classification of power consumer; Generating, transmission of electricity, the boosting of distribution, pressure reduction result in the voltage differences of transmission line of electricity.Before 1949, China's electric power industry development is slow, and electric pressure is various, has the transmission line of electricity of the electric pressures such as 22/33/44/66/110/154kV; Along with power industry construction is accelerated, China has progressively unified electric pressure, through development for many years, defines the several electric pressure of present 750/500/330/220/110/35/10/0.38kV.

The danger of high voltage transmission line is not only embodied in after human body is touched and can be electrically shocked, and is more just likely can get an electric shock when human body is not encountered; So hi-line often has a minimum safe distance scope.Hi-line hazard level again due to different electric pressure is different often, and electric pressure is higher, and its danger is often also larger, so the safe distance of hi-line is different, as following table:

Judge that human body has entered beyond safe distance the electric pressure that one, hazardous location important criteria is exactly hi-line.Hi-line electric pressure faced by when first will know that workman constructs, then could judge whether workman has the danger of electric shock.For above-mentioned background, this patent proposes a kind of method that self-adaptation differentiates hi-line electric pressure.

Summary of the invention

The object of the present invention is to provide a kind of hi-line electric pressure self-adaptation method of discrimination, the method utilizes Electric Field Distribution feature near hi-line, according to the radiation power frequency electric field signal detected, realize differentiating the self-adaptation of high voltage transmission line electric pressure by calculating.For achieving the above object, the technical solution used in the present invention is:

Hi-line electric pressure self-adaptation method of discrimination, comprises the following steps:

Step 1. detects electric field intensity, when electric field intensity value has exceeded detection threshold τ, starts record;

Step 2. is often advanced and is adopted spacing distance μ, records a sampled value, when forward travel distance is greater than integration window length m μ, starts summation, obtains integrated value ε in integration window;

Step 3. running integral window, often advance integration window sliding distance w μ, upgrades an integrated value, and the size of more up-to-date integrated value integrated value previous with it, if up-to-date integrated value is greater than previous integrated value, then continue measurement updaue; If up-to-date integrated value is less than its previous integrated value, then assert that its previous integrated value is maximum integral value ε _max;

Step 4. is by step 3 gained maximum integral value ε _maxthe corresponding maximum integral value of each electric pressure compares respectively with prestoring in system, finds out and ε _maximmediate pre-stored values, namely electric pressure corresponding to it regards as current voltage grade.

Beneficial effect of the present invention is: provide a kind of hi-line electric pressure self-adaptation method of discrimination, the method utilizes Electric Field Distribution feature near hi-line, according to the radiation power frequency electric field signal detected, realize differentiating the self-adaptation of high voltage transmission line electric pressure by calculating; For power worker's working environment provides effective safety guarantee.

Accompanying drawing explanation

Fig. 1 is 220kV horizontal wiring hi-line ambient radiation electric-field intensity distribution figure.

Fig. 2 is 220kV quadripartion hi-line ambient radiation electric-field intensity distribution figure.

Fig. 3 is 110kV gore space of lines electric field intensity and limit conductor spacing graph of a relation.

Fig. 4 is each electric pressure triangle wiring hi-line surrounding electric field intensity and distance relation comparison diagram.

Fig. 5 is hi-line electric pressure self-adaptation method of discrimination block diagram of the present invention.

Fig. 6 is electric-field intensity distribution curve under introducing noise conditions.

Fig. 7, Fig. 8 are simulation performance curve.

Embodiment

Below in conjunction with drawings and Examples, the present invention is described in further detail.

First from the principle bright: China's ultra-high-tension power transmission line adopts the alternating current transmission of electricity of 50Hz, can produce the power frequency electromagnetic field of alternation around power transmission line; Magnetic field intensity discloses the size of electric current in transmission line of electricity, and electric field intensity then reflects voltage swing on transmission line of electricity.Induction field can be produced around high voltage transmission line, to be illustrated in figure 1 under 220kV solid conductor horizontal wiring condition instantaneous electric field intensity distribution around power transmission line, electric field as seen from the figure around hi-line is the result of the phase 120 degree of radiated electric fields superpositions produced separately by three wires, so two lines centres have place's electric field intensity very little wherein.Be illustrated in figure 2 220kV conductors on quad bundled surrounding electric field intensity distribution, compare with Fig. 1, its surrounding electric field intensity is less, and this is also the reason place adopting split conductor.Can be found out by Fig. 1, Fig. 2, although various wirings mode hi-line surrounding electric field intensity distributions is complicated and different, be all that electric field intensity is also more and more less along with distance of wire is more and more far away substantially.

To be illustrated in figure 3 under 110kV triangle wiring condition intensity of radiation electric field with apart from limit conductor spacing relation curve, as can be seen from the figure, hi-line intensity of radiation electric field is exponentially decayed with the increase apart from limit conductor spacing, can reach very large in the local electric field intensity value near limit wire, but decay to very little value soon with the increase of distance.Similar with 110kV, different electric pressure hi-line surrounding electric field intensity level all obeys similar rule with distance, provide different electric pressure hi-line surrounding electric field intensity and the graph of a relation to limit conductor spacing as shown in Figure 4, as seen from the figure, under the different electric pressure hi-line in same position place, electric field intensity may differ more than 10 times, and along with the increase of distance, electric field intensity decays rapidly.

Because electric-field intensity distribution difference is larger under different electric pressure hi-line, so the electric pressure of hi-line can be distinguished according to the electric field intensity feature of a distance, but this needs accurately to know the distance of workman position to limit wire, and this often not easily realizes in practice of construction.Therefore, the present invention to decay violent characteristic according to the increase of transmission line of electricity surrounding electric field intensity distance, utilizes human body can be fairly obvious by the change of electric field intensity in the process of power transmission line far away, proposes a kind of hi-line electric pressure self-adaptation method of discrimination.

Set workman in the present invention and be positioned at ground below hi-line, advance to hi-line direction in position from afar, and often advance sampling interval distance μ samples an electric field intensity value, then when it is from start position forward travel distance n μ, sampling obtains n electric field intensity value, is designated as E successively ₁, E ₂..., E _n, and store for subsequent use;

Differentiate that electric pressure obtains by carrying out summation to up-to-date m the electric field intensity observed in an integration window, integration window length is m μ, and integration window sliding distance is w μ:

As forward travel distance m μ, start summation, obtain the 1st summing value

As forward travel distance (m+w) μ, obtain the 2nd summing value

The like, as forward travel distance (m+kw) μ, obtain kth+1 summing value

Obtaining one group of summing value ε ₀, ε ₁..., ε _kprocess in, when appearance from some summing value ε _jstart to have occurred continuous print decline, then think ε _jfor maximum integral value; Obtain the corresponding maximum integral value of q electric pressure in the manner described above be pre-stored within system.

In the present embodiment, hi-line electric pressure self-adaptation differentiates procedural block diagram as shown in Figure 5, and concrete steps are:

Step 1. detects electric field intensity, when electric field intensity value has exceeded detection threshold τ, starts record;

Step 2. is often advanced and is adopted spacing distance μ, records a sampled value, when forward travel distance is greater than integration window length m μ, starts summation, obtains integrated value ε in integration window; Add noise conditions Imitating electric field intensity sampled value as shown in Figure 6;

Step 3. running integral window, often advance integration window sliding distance w μ, upgrades an integrated value, and the size of more up-to-date integrated value integrated value previous with it, if up-to-date integrated value is greater than previous integrated value, then continue measurement updaue; If up-to-date integrated value is less than its previous integrated value, then assert that its previous integrated value is maximum integral value ε _max;

Step 4. is by step 3 gained maximum integral value ε _maxwith the corresponding maximum integral value of each electric pressure that prestores in system compare respectively, find out and ε _maximmediate pre-stored values namely electric pressure corresponding to it regards as current voltage grade.

By ε _maxrespectively with ask difference, obtaining one group of difference is:

$D_1=|{\mathrm{\ϵ}}_{max}-{\stackrel{\·}{\mathrm{\ϵ}}}_1|,D_2=|{\mathrm{\ϵ}}_{max}-{\stackrel{\·}{\mathrm{\ϵ}}}_2|,...,D_q=|{\mathrm{\ϵ}}_{max}-{\stackrel{\·}{\mathrm{\ϵ}}}_q|,$

Then the minimum value of this group difference is searched: D _m=min (D ₁, D ₂... D _q), then under preset test environment, the electric pressure of hi-line is pre-stored values corresponding electric pressure.

Be as shown in Figure 7, Figure 8 in the present embodiment to various measuring error and critical parameter to the influence curve judging accuracy, wherein, Fig. 7 is under 110kv, and fixing integration window length m μ is 3m, and under different integration window sliding distance w μ condition, electric field intensity measuremenrt error is on the impact judging accuracy; Fig. 8 is under 110kV, and fixing integration window length m μ is 3m, and integration window sliding distance w μ and sampling interval μ gets identical value, and the performance under this value different condition.As we know from the figure, when integration window sliding distance w μ and sampling interval μ all gets 0.5m, time integration window length m μ is 3m, good performance can be obtained.

The above, be only the specific embodiment of the present invention, arbitrary feature disclosed in this specification, unless specifically stated otherwise, all can be replaced by other equivalences or the alternative features with similar object; Step in disclosed all features or all methods or process, except mutually exclusive feature and/or step, all can be combined in any way.

Claims (1)

1. hi-line electric pressure self-adaptation method of discrimination, comprises the following steps:

Step 1. detects electric field intensity, when electric field intensity value has exceeded detection threshold τ, starts record;

Step 2. is often advanced and is adopted spacing distance μ, records a sampled value, when forward travel distance is greater than integration window length m μ, starts summation, obtains integrated value ε in integration window;

Step 3. running integral window, often advance integration window sliding distance w μ, upgrades an integrated value, and the size of more up-to-date integrated value integrated value previous with it, if up-to-date integrated value is greater than previous integrated value, then continue measurement updaue; If up-to-date integrated value is less than its previous integrated value, then assert that its previous integrated value is maximum integral value ε _max;

Step 4. is by step 3 gained maximum integral value ε _maxthe corresponding maximum integral value of each electric pressure compares respectively with prestoring in system, finds out and ε _maximmediate pre-stored values, namely electric pressure corresponding to it regards as current voltage grade.