RU2291536C2 - Device for detecting deposits on intermediate-span conductor of overhead power transmission line - Google Patents

Abstract

FIELD: monitoring overhead power transmission

lines for thawing deposits on conductors (ground wires) in due time.

SUBSTANCE: proposed device designed for detecting ice, snow, and frost on intermediate-span conductor of overhead power transmission line has remote-transmission unit, two force-metering transducers, each being loosely suspended between supporting structure crossarm and respective insulator string; lower ends of both insulator strings are hinged together to form V-shaped suspension with wire attached thereto; upper ends of transducer are secured to supporting structure crossarm and spaced apart through distance equal to length of insulator string and transducer to form equilateral triangle together with V-shaped suspension; device also has relative wind direction meter, wind speed meter, four functional converters, threshold shaper, two threshold elements, and OR gate.

EFFECT: provision for automation deposit detection process.

2 cl, 9 dwg

Description

The invention relates to the electric power industry and can be used for remote continuous real-time detection on the wire (phase wire or lightning protection cable) of an intermediate span of an overhead power transmission line of deposits of all possible types (ice, snow, frost and their mixtures) when monitoring overhead power transmission lines for timely melting of deposits on the wires (cables) of the line, preventing accidents on such lines due to mechanical overload of its elements. The device can also be used to obtain statistical information when compiling zoning maps for ice and wind loads.

State of the art

A known visual method for detecting deposits on the wires of an overhead power line. The disadvantages of the visual method are: firstly, the fact that it requires the direct presence of an observer in the place of sediment control, secondly, we practically do not realize it in conditions of poor visibility, and thirdly, the accuracy of the method due to visual assessment ("by eye ") is fundamentally not high.

Instrumental parametric methods for detecting deposits on wires based on measurement are also known: masses of deposits (gravitational method); increment of attenuation of high-frequency (HF) continuous sounding signals during their passage in the overhead transmission line due to absorption of the surface electromagnetic HF field in a non-ideal dielectric of deposits; the time delay of the pulse signals reflected from the clutch deposits from the probe pulse and the ratio of the amplitudes of these reflected pulses; an increase in the aerodynamic drag of the wire to the wind flow (wind pressure) due to an increase in its diameter by the thickness of the deposits [1-4].

When implementing the detection of deposits by the attenuation increment of the HF continuous sounding signals, it is practically impossible to unambiguously determine in advance the required value of the optimal threshold of attenuation increment, since the attenuation increment is significantly different for different types of deposits and different types of distribution of deposits along the wire. And besides the deposits themselves, the attenuation of the probing RF signals in the wire is affected to the same extent by random changes in the operating modes of the overhead lines and changes in meteorological parameters, especially air humidity. The inability to set the optimal value of the attenuation increment threshold leads to the fact that when certain types of deposits appear on the wire, they will be detected in a timely manner, while with other types of deposits they will be detected late or may not be detected at all, i.e. the total probability of the correct detection of all possible types of deposits will be low. If the threshold value of the attenuation increment is chosen small, then any small attenuation increments that are not associated with the appearance of deposits will cause a false signal to detect deposits on the wire, i.e. the probability of false alarm will increase.

Similar difficulties in determining the optimal value of the threshold for detecting deposits occur with pulsed sounding of overhead lines. At the same time, the effect of wave processes in the signal transmission lines on the parameters of the reflected pulse signals, which is difficult to register and account for, is added due to the presence of taps from the overhead lines and changes in the operating conditions of the load on them.

In principle, the simplest task of choosing the optimal threshold value for detecting deposits on a wire (and, therefore, stabilizing the detection characteristics) is solved when implementing the aerodynamic method of detecting deposits, because in a first approximation, the frontal resistance to the wind flow (wind pressure) with a fixed form of deposits (usually cylindrical) is determined by the cross-sectional area - the diameter of the deposits. But the defining disadvantage of the aerodynamic method for detecting deposits on the wire of the intermediate overhead overhead line, narrowing the scope of its application, is that in the absence of wind, the device that implements it does not work.

The most developed and practically used gravitational method for detecting deposits on the intermediate VL span wire is realized by measuring icy and icy-wind loads on the wire and then comparing the measured values with the predetermined values of the expected threshold loads (significant icy and icy-wind, dangerous, permissible loads etc.). However, the specific gravity of the deposits ranges from 0.1 to 0.9 g / cm ³ , therefore, the detection threshold (weight setting) must be adjusted in advance to stabilize the probability of correct detection - change by 9 times, otherwise the detection will be missed or issued false alarms. In addition to the noted task of choosing the optimal value of the detection threshold, a significant drawback of devices implementing this detection method is that the known devices do not separate the ice-wind load on the wire into ice and wind load components, which ultimately also worsens the detection characteristics, because the ratio between these components depends on the type of deposits, the type of distribution of deposits and the length of the intermediate span.

A device for measuring separately iced and wind loads on overhead power transmission lines, based on the calculation of icing and wind loads from the measured values of the icing-wind load and the deflection angle of the string of insulators with a wire under the influence of wind, measured using transformer sensors [5]. The main disadvantage of such a device is that it does not automatically detect the appearance of deposits on the wire, because there is no threshold (comparing) element and no threshold shaper. In addition, this device basically does not work in the absence of a load current in a phase wire suspended on a string of insulators with a force measuring sensor, as well as in the case of melting deposits on wires with direct current, because EMF in the transformer angle sensor appears in the presence of an alternating electromagnetic field caused by an alternating current of a phase wire.

A device for measuring separately iced, wind and icy-wind loads with control of the direction of the wind on overhead power lines [6]. It contains three force measuring sensors, each of which is suspended between the U-shaped traverse support and the upper end of the corresponding string of insulators with a phase wire. The lower end of the middle string of insulators is fixed on both sides by horizontal hinged insulating spacers in a stretch to both pillars of the support, and the ends of the right and left garlands of insulators are attached to the pillars of the pole to the left and right, respectively, with the same insulating spacers. When the wind is left or right, the left or right string of insulators with a phase conductor is deflected, respectively, in the wind, and then its load cell measures the ice-wind load, while the middle string does not deviate and its sensor measures only the ice load. Using the values of glaze-wind and glaze loads, non-linear converters calculate the actual wind load, which, together with the actual glaze load, is displayed by measuring instruments. The defining disadvantage of this device is that, in spite of the implemented measurement of the actual actual glaze, wind and glaze-wind loads separately, it does not automatically detect deposits on the intermediate span wire by the values of these loads, due to the lack of a threshold device and shaper thresholds. In addition, this device has a limited scope - only on the phase conductors of intermediate spans of single-circuit lines with double-column U-shaped supports.

There is a better device for measuring the icy load on phase wires (lightning cables) of an overhead power transmission line [7], which is more advanced by the principle of action and by design, which can be used on wires and cables of intermediate spans of multi-chain lines with any types of supports, selected as a prototype. The prototype contains a channel (device) of a telecast, a switch, and two spring weight sensors with contact groups of the weight setting on the moving axis of the sensor. Each sensor is movably suspended between the support traverse and the upper end of the corresponding insulator string, the lower ends of both insulator strings are pivotally connected to each other, forming a V-shaped wire suspension. This detector generates a signal of the presence of deposits when a certain weight of deposits is reached on the wire, by closing a group of contacts at the moment the wire passes the bottom point when the wire vibrates under the influence of wind in a plane perpendicular to the line of sight of the span. The defining disadvantage of such a device is that it can never generate a sediment detection signal in case of a strong uniform wind. will be constantly in a deviated (not vertical) position and contact groups will not be closed. In addition, even with a small specific weight of deposits, the group of contacts will not be closed and, therefore, a signal for detecting deposits will not be issued, i.e. there will be a skip of the presence of deposits on the wire (cable). With a small weight setting in the sensors, the increase in the probability of a false alarm will outstrip the growth in the probability of correct detection, since any accidental exceeding by a signal of a threshold that is not associated with the appearance of deposits (due to an alternating wind) will cause a detection signal to appear. Therefore, the device in question has a low probability of correct detection of deposits of all possible types.

SUMMARY OF THE INVENTION

The objectives of the invention is the development of a device for automatic detection of deposits of all possible types (icy, snow, hoarfrost and their mixtures) on a phase wire (ground wire) of an intermediate span of an overhead power line with stabilization of the probability of correct detection of deposits and stabilization of the probability of false alarm regardless of the specific gravity of these deposits and from the ratios of ice and wind loads on the wire (cable) in a device with a fixed threshold.

The goals are achieved in that the device for detecting deposits on the phase wire (ground wire) of the intermediate span of the power line with a fixed weight threshold simultaneously measures the gravitational ice load and the actual wind load on the wire with or without deposits created by this wind, as well as the relative direction and speed wind; by comparing the measured ice load with a fixed weight threshold, an acceptable probability of the correct detection of deposits with a high specific gravity is provided, while deposits with a low specific gravity by this threshold device may not be detected. Detection of deposits with a low specific gravity is provided by comparing the actual measured wind load on the wire with the current estimated wind load on the same wire without deposits, calculated from the measured speed and relative wind direction. In this case, if the actual measured wind load is greater than the calculated (with the wind setpoint), then a decision is made about the presence of deposits on the wire, and if the actual wind load is equal to or less than the calculated (with the wind setpoint), then a decision is made that there are no deposits wire.

In the device for detecting deposits on the wire of the intermediate span of an overhead power transmission line, using the well-known V-shaped suspension of the wire to the support beam through series-connected force measuring sensors and insulator strings, an additional relative wind direction meter, a wind speed meter, and elements that process signals from four sensors are added and comparing the obtained values with thresholds for deciding on the presence or absence of deposits on a wire (ground wire) diate passage of an overhead power line. The two meters introduced together with well-known sensors and additional processing elements made it possible to calculate the actual measured ice-wind, ice and wind loads on the wire with or without deposits, calculate the current value of the wind load on the same wire without deposits, compare the values of the ice load with a fixed weight threshold and actual measured with calculated wind loads between each other and based on the results of comparisons to develop a decision on the presence or absence of deposits on ode intermediate passage (ground wires) an overhead power line.

The inventive device provides continuous automatic real-time telemetry of the actual icy-wind, icy and wind loads on the wire (ground wire) of the intermediate span of an overhead power line with or without deposits and telemetry of the wind load on the same wire without deposits on lines with any operating voltage on all types of supports to automatically detect the appearance of all possible types of deposits on the wire (ground wire) of the intermediate span of the overhead line power transmission.

Disclosure of invention

The subject of the invention is a device for detecting deposits on a wire (ground wire) of an intermediate span of an overhead power transmission line.

A device for detecting deposits on a wire (ground wire) of an intermediate span of an overhead power transmission line, comprising a television transmission device and two force measuring sensors, each of which is suspended movably between the support beam and the corresponding insulator string, the lower ends of both insulator strings are pivotally connected to form a V-shaped suspension , to which the wire is attached, the upper ends of the sensors are attached to the support beam at a distance from each other, equal to the length of the string of insulators with the sensor, forming The V-shaped suspension is an equilateral triangle, characterized according to the invention in that a relative wind direction meter, a wind speed meter, four functional transducers, a threshold shaper, two threshold elements and an OR logic element are additionally introduced, with the first and second force sensors, wind speed meters and relative wind directions are respectively connected to the first, second, third and fourth inputs of the TV broadcast device, the first and second outputs of the mouth Telecasting devices are connected in parallel to the corresponding inputs of the first and second functional converters, the first input of the third functional converter is connected to the output of the first functional converter, the second input of the third functional converter and the first input of the first threshold element are connected to the output of the second functional converter, the output of which is connected to the first input of the logical of the OR element, the output of the shaper is connected to the second inputs of the first threshold element horns, the third and fourth outputs of the telecast device are connected respectively to the first and second input of the fourth functional converter, the output of the third and output of the fourth functional converters are connected respectively to the first and second inputs of the second threshold element, the output of which is connected to the second input of the OR logic element, the first and second the outputs of the logical element "OR" are respectively the first and second outputs of the device.

The specified set of features allows to achieve the objectives of the invention - a device for detecting deposits on a wire (ground wire) of an intermediate span of an overhead power line automatically and continuously measures the tension in the garlands of the V-shaped suspension of the wire, the relative direction and speed of the wind, based on which it calculates the actual ice and wind loads on the wire with or without deposits and the wind load on the same wire without deposits, compares the value of the ice load Visitors with a fixed weight threshold and the actual wind load with the estimated wind load on the wire without deposits (with the wind setpoint) and in cases of exceeding the weight threshold and (or) exceeding the actual wind load calculated without deposits (with the wind setpoint), a decision is made on the availability deposits on the wire (ground wire) of the intermediate span of an overhead power line. If the weight threshold is not exceeded and the actual wind load is equal to or less than the calculated one with the setting, then a decision is made on the absence of deposits on the wire (lightning cable).

It should be noted that automatic devices for detecting deposits on the wire of the intermediate span of an overhead power line, which simultaneously and continuously measure the tension of the sensors in the garlands of the V-shaped suspension of the wire, the relative direction and speed of the wind and based on them calculate the actual ice and wind loads on the wire with deposits with or without them, as well as the wind load on the wire without deposits, compare the value of the ice load with a fixed threshold and the actual wind load y with a calculated wind load on the wire without Fat (with the setpoint of the wind) and the results of the comparisons produce a decision on the presence or absence of deposits on the wire (ground wires) intermediate span overhead line, the applicants are not known.

However, the inventive device contains a set of features that are not the sum of technical solutions known from analogues and prototype, because contains distinctive features from the prototype, which are also absent in analogues. Indeed, in none of the known devices for measuring the actual icy, icy-wind and wind loads on the intermediate span wire with or without deposits, relative wind direction and wind speed meters are not contained and the wind load on the wire is not calculated from the output signals of these meters deposits, this load is not compared with the actual wind load, the calculated ice load is not compared with a fixed weight threshold, and the results of comparisons are not combined They are in the form of the output signal of the device on the element "OR" to develop a decision on the presence or absence of deposits on the wire.

Device description

A description of the device for detecting deposits on the wire of the intermediate span of an overhead power transmission line is illustrated in Figs. 1-6. Fig. 1 shows a functional diagram of the device, Fig. 2 is a vector diagram of the operation of load cells in a V-shaped wire suspension with four main possible load cases intermediate span wire, Figs. 3-6 show, respectively, diagrams of the first, second, fourth and third functional converters that implement calculations by the values of the loads N ₁ and N ₂ on each of the two force sensors, ice-wind N _sum (Fig. 3), total ice with the weight of the wire and fasteners V (Fig. 4), calculations by the speed W and the relative direction (azimuth) of the wind β wind load on the wire without deposits P _{in ( p)} (with the setpoint in the wind ΔР _{в (р)} ) (Fig. 5) and the actual wind load Р _{в (ф)} (Fig. 6).

Figure 1 shows the layout of the wind direction meter 1 and wind speed meter 2 on the lower crosshead 22 of the one-column intermediate support 21, the suspension circuit of the load sensors 3 and 4 on the lower crosshead 22 with garlands of insulators 23 and 24 supporting the phase wire 25, and functional circuit of the deposit detection device itself. The device comprises a relative wind direction meter 1, a wind speed meter 2, two force measuring sensors 3 and 4, a four-channel TV transmission device 5, four functional converters 6, 7, 9 and 10, a threshold shaper 8, two threshold elements 11 and 12, and an OR logic element 13.

Figure 3 presents a diagram of a first functional converter 6 having two inputs N ₁ and N ₂ and including four multipliers 14, a shaper 15 of constant value 2 cosγ, two adders 16 and a square root extraction element 17.

Figure 4 shows a diagram of a second functional converter 7 having two inputs N ₁ and N ₂ and consisting of an adder 16, a shaper 18 of constant value sinγ and a multiplier 14.

Figure 5 shows a diagram of the fourth functional Converter 9, which has two inputs β and W and consisting of a shaper 19 of a variable signal sin ² β from an input signal β, two multipliers 14 and a shaper 20 of constant value of the factor K.

6 shows a diagram of a third functional converter 10 and a vector diagram of its operation. This converter has two inputs N _sum and V and consists of two multipliers 14, the adder 16 and the square root extraction element 17. On the vector diagram of Fig.6, as on other sheets of the application description and drawings, indicated: V ₀ - weight of two garlands insulators with an intermediate span wire and fasteners, V 'is the weight of deposits on this wire, V is the total weight of two strings of insulators with fasteners, an intermediate span wire and deposits on it, R _{B (f)} is the actual wind load, R _{B (p)} - the design wind load on the pro od without Fat (with setting the wind? P _{B (p))} (? P _{B (p)} - setpoint exceeding the actual wind load calculated for optimum detection deposits on the wire of the pressure drop) and N _sum - total glazed ice and wind load on the wire with weighing two garlands of insulators, mounting hardware and intermediate span wires.

The device operates as follows.

In accordance with the principle of operation, two measurement channels work simultaneously and in a coordinated manner in the device: the channel for measuring the actual ice and wind loads on the wire with or without deposits and the channel for measuring the wind load on the wire without deposits. The second channel basically does not work if the first channel does not work. When describing the operation of the device, we consider the operation of these two channels sequentially one after another, and then in their interaction with each other, which allows to achieve the purpose of the invention.

The power load on the intermediate span wire and, consequently, on the V-shaped suspension in the general case consists of three components: V ₀ , V 'and P _{B (f)} . These three components act independently of each other, and V ₀ cannot be equal to zero. Given these circumstances, there are basically six possible power loads on the V-shaped suspension of the wire, the last two of which differ only in the opposite direction of the wind, therefore, we consider only four main options presented in figure 2.

The first option is that there is no deposit on the wire V '= 0, there is no wind Р _{В (ф)} = 0, and, therefore, the sensors 3 and 4 perceive the weight of two strings of insulators 23 and 24 with the corresponding mounting fittings along with the weight of wire 25 of the intermediate span V ₀ , the output signals of the sensors 3 and 4 are equal to each other N ₁ = N ₂ , V = V ₀ , N _sum = V ₀ (figure 2, a).

In the second option - deposits on the wire are V '> 0, there is no wind Р _{В (ф)} = 0, the weight of deposits V' is added to V ₀ , the signals from sensors 3 and 4 are equal to each other, and larger in magnitude than in the first load option N '= N' ₂ > N ₁ = N ₂ , V = V ₀ + V ', N _sum = V ₀ + V' (Fig.2, b).

(фиг.2, в). В случае, если ветер дует справа налево, векторная диаграмма будет представлять собой зеркальное отображение фиг.2,в и на ней только векторы N₁ и N₂ поменяются местами.In the third option - there is no deposit on the wire V '= 0, there is wind, for example, from left to right P _{B (f)} > 0, wind load P _{B (f) is} added perpendicularly to V ₀ , the output signals of sensors 3 and 4 are not equal between N ₁ > N ₂ , V = V ₀ ,

(figure 2, c). In case the wind blows from right to left, the vector diagram will be a mirror image of figure 2, in and on it only vectors N ₁ and N ₂ will change places.

(фиг.2,г). В случае, если ветер дует справа налево, то векторная диаграмма будет представлять собой зеркальное отображение фиг.2, г и на ней только вектора N₁ и N₂ поменяются местами.In the fourth embodiment, there is deposits on the wire V '> 0 and there is wind, for example, from left to right Р _{В (ф)} > 0, weight of deposits on the wire V' and wind load Р _{В (ф)} , perpendicular to ice, are added to V ₀ the signals from sensors 3 and 4 are not equal to each other N ₁ > N ₂ , V = V ₀ + V ',

(figure 2, g). If the wind blows from right to left, then the vector diagram will be a mirror image of figure 2, d and on it only the vectors N ₁ and N ₂ will change places.

Let us consider in more detail the operation of the proposed device with the simultaneous influence of wind and deposits on the wire according to the fourth embodiment (Fig. 2, d), and for the other three variants of power loads, we note only changes in its operation due to the absence of certain load components.

. В нем угол γ=180°-α, а угол α - это угол между осями гирлянд изоляторов в месте их соединения и крепления к ним провода. Второй функциональный преобразователь 7 (фиг.4) по входным сигналам N₁ и N₂ вычисляет величину V по выражению V=(N₁+N₂)×sinγ. Сигнал гололедно-ветровой нагрузки N_сум с выхода первого функционального преобразователя 6 (фиг.1) поступает на первый вход третьего функционального преобразователя 10. Сигнал V=V'+V₀ с выхода второго функционального преобразователя 7 поступает на второй вход третьего функционального преобразователя 10 и на первый вход первого порогового элемента 11, на второй вход которого поступает сигнал V₀+ΔV с выхода формирователя порога 8. Выход первого порогового элемента 11 соединен с первым входом логического элемента ИЛИ 13. Третий функциональный преобразователь 10 (фиг.6) вычисляет величину фактической ветровой нагрузки на провод по выражению

, которая с выхода третьего функционального преобразователя 10 (фиг.1) поступает на первый вход второго порогового элемента 12. Одновременно с этим под действием ветра измеритель относительного направления ветра 1 и измеритель скорости ветра 2 вырабатывают соответствующие сигналы β и W, которые через отдельные четвертый и третий каналы устройства телепередачи 5 поступают соответственно на второй и первый вход четвертого функционального преобразователя 9. Функциональный преобразователь 9 (фиг.7) рассчитывает ветровую нагрузку на провод промежуточного пролета без отложений Р_В(р) (с уставкой ΔP_в(р)) по выражению P_В(р)=sin²β×W×K=Р_в(ф)+ΔP_в(р), где К - коэффициент пропорциональности для конкретного провода с сечением F, длиной L. Сигнал Р_В(р)=Р_в(р)+ΔР_в(р) с выхода четвертого функционального преобразователя 9 (фиг.1) поступает на второй вход второго порогового устройства 12, где сравнивается с Р_В(ф). Результат сравнения с выхода второго порогового устройства 12 поступает на второй вход логического элемента ИЛИ 13.Suppose that the wire 25 with deposits on it with some force acts (blows) the wind from left to right across the axis of sight of the overhead power line, as shown in figure 2, The signals of the sensors N ₁ > N ₂ (and vice versa, if the wind blows from right to left, then N ₁ <N ₂ ) in the form of voltages or currents, respectively, through the separate first and second channels of the television transmission device 5 are sent in parallel to the corresponding inputs of the functional converters 6 and 7. The first functional converter 6 (Fig. 3), using the input signals N ₁ and N _2, calculates the value of the ice-wind load N _sum , according to the expression

. In it, the angle γ = 180 ° -α, and the angle α is the angle between the axes of the insulator strings at the point of their connection and the wires attached to them. The second functional Converter 7 (figure 4) from the input signals N ₁ and N ₂ calculates the value of V by the expression V = (N ₁ + N ₂ ) × sinγ. The signal of ice-wind load N _sum from the output of the first functional converter 6 (Fig. 1) is supplied to the first input of the third functional converter 10. The signal V = V '+ V ₀ from the output of the second functional converter 7 is fed to the second input of the third functional converter 10 and at the first input of the first threshold element 11, the second input of which receives a signal V ₀ + ΔV from the output of the threshold shaper 8. The output of the first threshold element 11 is connected to the first input of the OR gate 13. The third functional pre browser 10 (Fig.6) calculates the actual wind load on the wire by the expression

which, from the output of the third functional converter 10 (FIG. 1), enters the first input of the second threshold element 12. At the same time, under the influence of the wind, the relative wind direction meter 1 and wind speed meter 2 generate the corresponding signals β and W, which, through a separate fourth and the third channels of the TV transmission device 5 are respectively supplied to the second and first input of the fourth functional converter 9. Functional converter 9 (Fig. 7) calculates the wind load on the industrial wire diate span without Fat P _{B (p)} (with the setpoint ΔP _{a (p))} for the expression of P _{B (p)} = sin ² β × W × K = F _{in (f)} + ΔP _{in (p),} where K - factor proportionality for a particular wire with a cross section F, length L. The signal P _{B (p)} = P _{in (p)} + ΔP _{in (p)} from the output of the fourth functional Converter 9 (Fig.1) is fed to the second input of the second threshold device 12, where compares with P _{B (f)} . The comparison result from the output of the second threshold device 12 is fed to the second input of the OR gate 13.

In the considered embodiment, the load with a high specific gravity of deposits on the wire V '> 0, the value V = V ₀ + V' at the first input of the first threshold element 11 will be greater than V ₀ + ΔV (with the appropriate choice of the detection setpoint ΔV), the threshold element 11 will generate an excess signal, which through the logic element 13 will be issued as a signal "There is deposits." The setting ΔV is the optimal value selected based on the given probability of detecting deposits with a high specific gravity. And the wind pressure detection channel in this case most likely will not work, because the diameter of the clutches of deposits with a high specific gravity (pure ice) at a given weight will be much smaller than the diameter of the clutches of hoarfrost, hoarfrost or mixtures thereof. If there is deposits on the wire with a low specific gravity, the weight detector will most likely not work, and the detection channel by wind pressure will most likely work, because P _{B (f)} > P _{B (p)} by an amount not less than the setting ΔP _{B (p)} . This is due to the fact that due to the increase in the cross-sectional area of the wire by the thickness of the deposits perpendicular to the wind flow (wind pressure), it increases in proportion to the increase in the diameter of the deposits, which leads to an increase in the aerodynamic drag force to this wind - an increase in the actual wind load on the wire P _{B (f)} , which in the presence of deposits on the wire there will always be more than the calculated wind load on the same wire without deposits P _{B (p)} taking into account the setting ΔP _{B (p)} . Therefore, the signal P _{B (f)} in the presence of deposits on the wire is larger in magnitude than the signal P _{B (p)} + ΔP _{B (p)} , and the second threshold element 12, comparing them with each other in magnitude, will generate a signal for the presence of deposits on the wire an intermediate span of an overhead power line, which will appear at the output of the device through the second input of the OR 13 logic element in the form of a “There is a deposit” signal.

, преобразователь 7 вычислит V=V₀, которая не превысит V=V₀+ΔV на первом пороговом элементе 11, и он не выдаст сигнал обнаружения отложений на проводе, преобразователь 10 вычислит

, функциональный преобразователь 9 вычислит Р_В(р)+ΔР_в(р), которая в этом случае будет меньше Р_в(ф), и поэтому второй пороговой элемент 12 не выдаст сигнала обнаружения отложений на проводе. Следовательно, на выходе элемента ИЛИ 13 будет сигнал «Нет отложений».In the third version of the load - there is no deposit on the wire V '= 0, but there is a lateral wind from left to right Р _{В (ф)} > 0, functional converter 6 will form a load on the intermediate span wire

, the converter 7 will calculate V = V ₀ , which does not exceed V = V ₀ + ΔV on the first threshold element 11, and it will not generate a deposit detection signal on the wire, the converter 10 will calculate

, the functional converter 9 will calculate P _{B (p)} + ΔP _{in (p)} , which in this case will be less than P _{in (f)} , and therefore the second threshold element 12 will not give a signal for detecting deposits on the wire. Therefore, the output of the element OR 13 will be a signal "No deposits".

In the second load case, there is deposits on the wire V '> 0, there is no crosswind, N ₁ = N ₂ , N _sum = V = V ₀ + V', converter 9 will calculate the value of P _{B (p)} + ΔP _{B (p)} > 0, and the transducer 10 calculates the value of P _{B (f)} = 0, the second threshold element 12 does not produce a detection signal, the transducer 7 calculates V = V '+ V ₀ , which in the case of a high specific gravity of deposits will exceed the setting V ₀ + ΔV by the first threshold element 11, and a signal for detecting deposits on the wire is generated. If the specific gravity of the sediments is small, then the weight channel will not detect deposits on the wire - deposits will be skipped.

In the first version of the load, there are no deposits and there is no wind, respectively, there will be no excess of the compared signals at any of the threshold elements, the correct solution will be “No deposits” and, accordingly, there will be no false detection signal at the device output.

Thus, due to the introduction and use of two uncorrelated thresholds, it is possible to significantly increase the probability of detecting deposits on a wire with low specific densities with an insignificant increase in the probability of false detection of deposits.

It should be noted that in the proposed device for detecting deposits on the wire of an intermediate span of an overhead power transmission line, the probability of detecting all possible types of deposits will, ceteris paribus, increase due to an increase in the probability of correct detection of deposits with low specific densities (which are missed by the weighted detection channel) by the aerodynamic channel with a slight increase in the probability of false detection.

The four-input TV transmission device 5 (Fig. 1) can be implemented as one common TV channel with a temporary seal, having an input switch with four inputs from meters and sensors 1, 2, 3, and 4, a common TV channel, a sampling and storage device with four separate outputs to functional converters 6, 7, 9 and a synchronizing pulse generator, which provides alternating connection of the first input only with the first output, the second input only with the second, etc.

If the inventive device is used to detect deposits on a lightning protection cable of an intermediate span of an overhead power transmission line, then in the device itself it is only necessary to change the value of the coefficient K and the setting V ₀ + ΔV and the lightning cable 26 to attach to a V-shaped suspension with force measuring sensors similar to that considered for a phase wire as shown in figure 1, in the upper left.

Since all other climatic influences (temperature, pressure, humidity, etc.) and changes in the operating modes of the overhead power line have almost the same effect on the force sensors and a common TV transmission device is used, and the sensor signals are compared differentially (relative to each other), then the above effects practically do not affect the accuracy of measurements and the device for all types of pylons of overhead power lines remotely automatically continuously in real m-time at an intermediate span produces all possible detection deposits, including low specific density of the wire (ground wires) intermediate span the overhead power line.

Information sources

1. Auth. testimonial. USSR No. 1173473, IPC N 02 G 7/16, 1985.

2. Auth. testimonial. USSR No. 748615, IPC N 02 G 7/16, 1980.

3. Auth. testimonial. USSR No. 603034, IPC N 02 G 7/16, 1978.

4. Application for invention No. 2004117685/09 (019083) dated 10.06.2004.

5. Patent for the invention of the Russian Federation No. 2145758, IPC N 02 G 7/16, 2000.

6. Patent for the invention of the Russian Federation No. 2212744, IPC N 02 G 7/16, 2003.

7. Auth. testimonial. USSR No. 519806, IPC N 02 G 7/16, 1976.

Claims (2)

1. A device for detecting deposits on the wire of the intermediate span of an overhead power transmission line, comprising a television transmission device and two load-sensing sensors, each of which is suspended movably between the support beam and the corresponding insulator string, the lower ends of both insulator strings are pivotally connected to form a V-shaped suspension, to which the wire is attached, the upper ends of the sensors are attached to the support beam at a distance from each other, equal to the length of the string of insulators with the sensor, forming a V-shaped an equilateral triangle suspension, characterized in that a relative wind direction meter, a wind speed meter, four functional transducers, a threshold shaper, two threshold elements and an OR logic element are additionally introduced, with the first and second force sensors, wind speed and relative wind direction meters, respectively connected to the first, second, third and fourth inputs of the TV broadcast device, the first and second outputs of the TV broadcast device parallel to the corresponding inputs of the first functional converter, which calculates the value of the total ice-wind load on the wire, and the second functional converter, which calculates the total weight of two garlands of insulators with mounting fittings, intermediate span wire and deposits on it, the first input is connected to the output of the first functional converter the third functional converter that calculates the actual wind load on the wire, the output of the second functional the second input of the third functional converter and the first input of the first threshold element, the output of which is connected to the first input of the OR logic element, are connected to the second input of the first threshold element, the output of the threshold driver is connected, the third and fourth outputs of the TV transmission device are connected respectively to the first and second inputs of the fourth functional a converter that calculates the wind load on the intermediate span wire without deposits, the output of the third and the output of the fourth function ionalnyh converters are respectively connected to first and second inputs of the second threshold element whose output is connected to the second input of the logic element "OR", the first and second outputs of the OR gate are respectively the first and second outputs of the device. 2. The device according to claim 1, characterized in that the upper ends of the load cells are attached to the support beam at a distance from each other, not equal to the length of the string of insulators with the sensor, forming an isosceles triangle with a V-shaped suspension.

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