RU2472170C1 - Detection of fault area in electric circuits of power supply using principle of remote protection - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: whenever a grounding fault (17) occurs, measured current value is determined in the area, as well as the measured voltage value, and the measured value of the grounding current is determined. Using the determined measured values, the value of the fault area is calculated, which indicates the grounding fault area (17) in the area (10). The value of the fault area is formed using impedance of an area line and earth impedance for soil arranged along the area (10). The earth impedance value used to form the fault area value is set dynamically. For dynamic detection of the earth impedance value a model description (28) is used, which takes into account at least two factors (24, 25) of impact at earth impedance and provides a characteristic (28) of earth impedance along the entire length of the area (10).

EFFECT: more accurate detection of arising ground fault location.

12 cl, 4 dwg

Description

The invention relates to a method for determining the location of a ground fault in a section of an electric power supply line according to the principle of distance protection, and when a ground fault occurs, a measured current value is determined, indicating the current flowing in the section, a measured voltage value is determined, indicating the voltage applied to the section, and also determined the value of the ground current, indicating the current flowing along the section of the ground, and using certain measured values calculated Xia value of fault location, which indicates the location of the ground fault at a portion where the value fault location is obtained using an impedance plot line and ground impedance for ground running along the section, and wherein the value of the earth impedance applied to obtain the value fault location, is established dynamically.

The invention also relates to an electrical distance protection device for determining the location of a ground fault in a section of an electric power transmission line with a device for determining measured values for determining measured current and voltage values, as well as ground current values that indicate the values of the current flowing in the section and the voltage applied to it , as well as the earth current flowing along the site, and with a control device, which, using certain measured values, There is a fault location that indicates the location of the ground fault in the area, and this location of the failure is formed using the line impedance of the section and the ground impedance along the section.

To control and protect electric power supply networks, so-called electric protective devices are usually used. The electrical protective device receives the measured values at the measurement site of the electric power supply network, which characterize the operating state of the electric power supply network. In this case, we can talk, for example, about the measured values of current and voltage. Based on these measured values and using special protection algorithms, the protective device makes a decision on whether the part of the electric network it controls is in an acceptable or unacceptable working condition. An unacceptable operating state, for example, occurs when a short circuit occurs in the controlled part of the electric power supply network. If an unacceptable operating state takes place, the protective device usually automatically issues a so-called error command to the power switch that belongs to it, which, in response to the error command, opens its switching contacts and thereby disconnects the faulty section from the rest of the power supply network.

A frequently used electrical safety device is, for example, the so-called distance protection device. The distance protection device measures the currents and voltages that occur at the place of measurement of the electric power supply line, and calculates from them the impedance value of the electric power supply line. Based on the calculated impedance value, it is possible, for example, using certain tripping characteristics, to check whether a malfunction, such as a short circuit, has occurred on the electric power supply line. If a malfunction occurs, the distance protection device issues an error command to the corresponding power switch, which then disconnects the section of the power supply line with the fault from the rest of the power supply network. Additionally, the distance protection device also indicates the location of the malfunction that arose in the controlled electric power supply line. Distance protection devices are often used to control electric power supply lines, because they have high selectivity and can make independent decisions, and it does not require communication with another distance protection device.

Short circuits can occur, for example, between two or three phases of an electric power supply line (the so-called conductor-conductor short circuit) or between the corresponding phase and electrical ground (the so-called conductor-ground conductor short circuit). In the case of a conductor-conductor short circuit between two or three phases of the power supply line, recognition and determination of the location of the short circuit is very easy, since the line impedances required for determining the impedance threshold value for lines affected by the fault are usually known.

However, much more often than short circuits of the "conductor-conductor" type, short circuits of the "conductor-ground" type occur, moreover, we are talking about essentially single-phase short circuits involving grounding. To determine the location of such short circuits of the "conductor-ground" type, knowledge of the soil impedance along the controlled section of the electric power supply line is necessary, since it significantly affects the impedance of the conductor-ground circuit measured by the distance protection device.

The adjustable parameter used for the ground impedance, which should be set as the parameter of the electric distance protection device, is usually set as a constant adjustable parameter of the distance protection device. This value can either be derived from the parameters of the electric power supply line, such as, for example, the impedance of a zero sequence system (phases) or the impedance of a direct sequence system (phases), or measured explicitly.

In general, the ground impedance value can be set dynamically. For this, as is known, for example, from the earlier patent application PCT / EP2007 / 006703 of the applicant, the environmental parameters, on which the impedance depends, are directly measured using sensors connected to the distance protection device. Due to this, the accuracy of determining the location of the fault increases.

The basis of the invention is to propose a method of the above type, which provides the ability to more accurately determine the location of the ground fault. Another task is to offer an appropriate distance protection device.

Regarding the method, this problem is solved in that for the dynamic determination of the ground impedance value, a model description is used that takes into account at least two factors influencing the ground impedance and provides a characteristic of the ground impedance along the entire length of the plot.

A significant advantage of the method according to the invention is that not only individual, measured by points - most often obtained near the distance protection device - measured values of influence factors are used to determine the impedance of the earth, but instead a complete characteristic of these influence factors along the section of the power supply line . The value of the influence parameters and, thus, the corresponding ground impedance usually fluctuates along the site. By considering at least two influence factors, it is possible to determine the impedance of the earth even more accurately than when considering a single influence factor.

Specifically, according to a preferred embodiment of the method according to the invention, it can be provided that at least two parameters from the following list can be applied as influence factors: air humidity, air temperature, air ionization degree, humidity of the corresponding soil section, temperature of the corresponding soil section, soil structure for the corresponding site of the soil, the distance from the site to the soil. These parameters represent precisely the main influence factors that cause the change in the impedance of the earth along the section of the power supply line.

Another preferred embodiment of the method of the invention further provides that at least two applied influence factors are measured and / or calculated. The measurement can be carried out by means of a distributed image of the sensors. Between the individual sensors, the value of the corresponding influence factor can be calculated, for example, by interpolation. In addition, the calculation is possible by deriving the value of the desired influence factor from other parameters, for example, when determining soil moisture based on the amount of precipitation that has taken place.

Another preferred embodiment of the method of the invention further provides that at least two applied influence factors are obtained from at least one data bank, and at least one data bank contains a mapping of geographical location values with corresponding values of the influence factors. Such data banks are often made available for various applications and should not be generated specifically to determine the impedance of the earth.

Advantageously, in this regard, it can be provided that the values of the influence factors contained in the at least one databank are consistent in real time with the actual conditions.

In order to simply select the necessary values of the influence factors as far as possible, in addition, it can be provided that the description of the model is formed by selecting such values of the influence factors that are compared with the geographical values of the location along which the given section extends. In this case, the corresponding values of the influence factors from the data bank should be read only on the basis of those geographical values of the location that describe the characteristic of the section of the power supply line.

Specifically, in the case of at least one databank, it may be a geographic information system and / or a weather databank.

Another preferred embodiment of the method of the invention further provides that a description of the model is generated by the remote data processing device and provided from the remote data processing device to the control device of the distance protection device, which calculates the value of the fault location. Thus, the description of the model can be calculated by a remote data processing device, which can be, for example, a relatively high-performance personal computer in a network control center. Determining the location of the fault based on the calculated model description for the ground impedance can be performed by the control device of the distance protection device. Such control devices usually do not provide the high computing capabilities that a personal computer has at a network control point.

In order not to uselessly transfer large amounts of data between the remote data processing device and the control device and not increase the communication load on the communication connection between the two, it is proposed in accordance with another preferred embodiment that the model description is only then transmitted from the remote data processing device to the control device when the control device requests a description of the model.

In this regard, it may, for example, be provided that the control device requests a description of the model after a malfunction occurs in the area, since only then can a targeted determination of the location of the malfunction be performed.

As an alternative to calculating the model description by the first data processing device, it may also be provided that the distance protection device, which is located on the site, receives at least two applied influence factors from at least one data bank, and the distance protection device control device the basis of the accepted influence factors forms a description of the model. This is achieved, in particular, in the case of a distance protection device with high computing power, which is directly connected to one or more data banks via a communication connection to an Internet connection.

With respect to the electric distance protection device, the above problem is solved by the distance protection device of the aforementioned type, in which the control device is configured to implement the method according to one of the above described embodiments.

The invention is further explained in more detail using examples with reference to the drawings, which show the following:

Figure 1 - schematic representation of a device for remote protection of a three-phase power transmission line,

Figure 2 is a schematic diagram for explaining a definition of a model description for setting an earth impedance,

Figure 3 is a schematic representation of a distance protection device that is connected to a remote data processing device through a communication connection,

4 is a schematic representation of a distance protection device that is connected directly to two data banks by means of a communication connection.

1 shows a portion 10 of a three-phase power transmission line not shown in more detail. Section 10 on its one side is limited by the location A of the measurements of the distance protection device 11. On its second side, section 10 is bounded by a dashed line B, which, for example, indicates the measurement location of another distance protection device, which is not shown in FIG. Section 10 of the three-phase power transmission line, limited by the location A of the measurements and the dashed line B, is controlled by an electric distance protection device 11 for unacceptable operating states, for example, short circuits. To this end, the measured current and voltage of the electric power transmission line are taken to the corresponding phases 10a, 10b and 10c of section 10 by means of schematically represented current converters 12a, 12b and 12c, and the measured values of the current and voltage of the electric power transmission line are taken and fed to the device 14 for recording the measured values device 11 distance protection. In addition, the measured value recorded by another current transducer 16 (also located at the measurement site A) also receives a measured ground current value to the measured value recording device 14.

In the device 14 recording the measured values, the transformation of still relatively high levels of current and voltage issued from the outputs of the converters 12a, 12b and 12c, as well as 16 currents or converters 13a, 13b and 13c, to current and voltage levels that can be processed by the device is usually performed 11 distance protection. In addition, an analog-to-digital conversion or, if necessary, other pre-processing steps, for example, filtering the received measured values, is usually performed in the measured value recording device. If the measured values in the form of current or voltage indicators must be further processed, then usually the formation of current or voltage indicators is also performed, so that the generated current or voltage indicators then have information on the amplitude and phase position of the current and voltage of the individual phases 10a, 10b and 10c of section 10 electric power transmission line or grounding current.

Registered by the device 14 recording the measured values and, if necessary, pre-processed measured values of current and voltage are then supplied to the device 15 of the control device 11 of the distance protection. The control device 15 determines, based on algorithms known to those skilled in the art, whether there is a malfunction in the portion 10 of the electric power transmission line, and furthermore, recognizes a malfunctioning circuit (for example, a conductor-conductor circuit between phases 10a and 10b or a conductor-to-ground circuit between phase 10c and ground). If the control device 15 recognizes such a malfunction, it outputs the corresponding error signals to the circuit breakers 18a, 18b, 18c relating to the individual phases 10a, 10b and 10c, in order to disconnect the phase (s) affected by the malfunction from the rest of the power transmission line .

After that, the control device 15 calculates, based on the measured current, the measured values of the ground current and voltage, the value of the fault location, which indicates the fault location in section 10 (most often relative to the line length in section 10). This requires the impedances of the conductors of the respective phases and, in the event of a ground fault, the earth impedance for a region of soil running along the site. Below, the determination of the location of the ground fault will be considered in more detail.

According to FIG. 1, it is assumed that there is a short circuit between phase 10c and ground. Thereby, a so-called “conductor-ground” circuit is formed between phase 10c (conductor) and ground, which passes from the measurement site A through phase 10c to the short-circuit point 17 and from there again back through the earth to the measurement site A or to the installation location of the converter 16 current.

For further explanation, first of all, based on FIG. 1, the calculation of the value m of the fault location via the control device 15 of the distance protection device 11 should be output. This value m of the fault location gives - in relation to the entire length of the monitored section 10 - the place where a short circuit 17 occurred between phase 10c and ground. This place is required in order to be able to repair any defect in the power supply line and eliminate the cause of the malfunction.

To calculate the value m of the fault location to the conductor-ground circuit formed as shown in FIG. 1 due to a short circuit 17 between the measurement site A, the well-known circuit rule is applied according to the second Kirchhoff law. From this we obtain the following equation of loop currents:

(1)

(one)

The symbols in the formula mean the following (see also Figure 1):

измеряемый прибором 11 дистанционной защиты показатель напряжения, который дает напряжение между фазой 10с и заземлением;

the voltage indicator measured by the distance protection device 11, which gives a voltage between the phase 10c and the ground;

измеряемый прибором 11 дистанционной защиты показатель тока, который дает ток, протекающий в фазе 10с;

the current indicator measured by the remote protection device 11, which gives the current flowing in phase 10c;

расстояние от места А измерения до места неисправности короткого замыкания 17, отнесенное ко всей длине участка 10 (значение местоположения неисправности);

the distance from the place A of the measurement to the place of failure of the short circuit 17, related to the entire length of section 10 (value of the location of the failure);

импеданс системы прямой последовательности (фаз);

impedance of a direct sequence system (phases);

падение напряжения в месте неисправности;

voltage drop at the fault location;

измеряемый прибором 11 дистанционной защиты показатель тока заземления, который дает ток, протекающий в заземлении; и

measured by the device 11 distance protection indicator of the ground current, which gives the current flowing in the ground; and

полный импеданс земли вдоль участка 10 линии энергоснабжения.

total ground impedance along section 10 of the power supply line.

на месте неисправности обычно при одностороннем определении места неисправности не может быть определено. Однако им можно пренебречь без заметного влияния на конечный результат.Using this equation (1), the control device 15 of the distance protection device 11, when knowing the values for the impedance of the conductor and the impedance of the earth, can determine the value m of the fault location, since the corresponding measured values of the current, ground current and voltage are known from measurements at the time instant short circuits. Voltage drop value

at the location of the malfunction, it is usually not possible to determine the location of the malfunction with a one-way determination. However, it can be neglected without a noticeable effect on the final result.

Although the measured values of current, grounding current, and voltage are presented as equations in equation (1) and, therefore, they include information on the amplitude and phase position, the described method can also be carried out with scalar quantities (amplitudes, rms values, effective values )

фазы 10с в значительной степени является постоянным и не зависит от внешних влияний, значение импеданса заземления

изменяется в зависимости от факторов влияния, таких как, например, температура и влажность. Так, например, грунт, пропитанный влагой, имеет меньший импеданс, чем сухая почва. Кроме того, импеданс заземления может также быть зависимым от влажности воздуха, температуры воздуха, степени ионизации воздуха, температуры соответствующего грунта, структуры почвы для соответствующего грунта и расстояния от участка 10 электрической линии энергоснабжения от почвы.While the impedance of the conductor

phase 10c is largely constant and independent of external influences, the value of grounding impedance

varies depending on influence factors, such as, for example, temperature and humidity. So, for example, soil saturated with moisture has a lower impedance than dry soil. In addition, the grounding impedance may also be dependent on air humidity, air temperature, degree of ionization of the air, temperature of the corresponding soil, soil structure for the corresponding soil, and distance from the portion 10 of the power supply line from the soil.

импеданса земли, которое, в конечном счете, должно учитываться в приборе 11 дистанционной защиты, составляется тогда из парциальных импедансов земли от Z1 до Zn согласно уравнению (2):Taking into account at least two influence factors that affect the value of the earth's impedance along the section of the electric power supply line, you can now generate a model description that gives the value of the earth's impedance along the section 10 of the electric power supply line. Value

the earth impedance, which, ultimately, must be taken into account in the device 11 distance protection, is then composed of the partial earth impedances from Z1 to Zn according to equation (2):

(2)

(2)

moreover

парциальный импеданс земли;

partial impedance of the earth;

n: current variable

L: current variable at full length of section 10,

задается посредством описания модели. Описание модели само определяется на основе по меньшей мере двух применяемых фактов влияния на отдельных - выбранных произвольно любой малой величины - отрезках участка n до L для участка 10 электрической линии энергоснабжения.and each partial impedance of the earth

defined by the model description. The description of the model itself is determined on the basis of at least two applied facts of influence on the individual - arbitrarily selected any small values - segments of section n to L for section 10 of the electric power supply line.

посредством простого применения уравнения (1) определить место n неисправности с высокой точностью.The device 15 of the control device 11 of the distance protection can using the specified description of the model of the impedance of the earth

by simple application of equation (1) to determine the location n of the malfunction with high accuracy.

In order that the control device 15 of the distance protection device 11 can provide a description of the model, the distance protection device 11 has a communication device 19. This is described in more detail in connection with FIGS. 3 and 4.

Based on FIG. 2, for example, the formation of a model description 28 for ground impedance along a portion of an electric power supply line is explained. To generate a description of model 28, the values of at least two of the above factors of influence along the plot are used. Such values are pre-stored in one or more data banks in which the values of the individual influence factors are given for exact locations, that is, each value of the influence factor is associated with a geographical location (for example, by indicating geographical longitude and latitude). Examples of such data banks are geographic information systems that contain data on the topology and characteristics of the soil, as well as on the presence of forests, watercourses, buildings, etc., or weather banks that contain information on precipitation, temperatures, humidity, insolation, etc. d. If the values of certain influence factors (for example, soil moisture) cannot be directly read from the provided data banks, then they can be calculated or estimated using the available data from the data banks. So, for example, soil moisture can be determined from the structure of the soil and precipitation over the past period of time.

Usually, the corresponding data banks are not supported by the power supply network operator itself, but can be obtained from a third party, for example, from providers of weather information systems or geographic information systems. The operator of the electric power supply network, most often, only needs to form a description of the model from these provided data banks. However, it is also possible that the model description is generated by a third party and then made available to the operator of the electric power supply network.

Figure 2 shows, for example, the formation of a description 28 of the model for the impedance of the earth along the considered section of the electric power supply network using the information available in widespread data banks. For this, first of all, a high-altitude profile of the electric power supply network is required in order to present the exact course of the section of the electric power supply network in three spatial coordinates. Such a height profile is shown, for example, only in FIG. 2 and indicated by a reference numeral 21. On a height profile 21, the height of the plot is plotted relative to the reference height (usually above sea level) depending on its length. Such a high-altitude profile can be obtained, for example, using an electronic geographic map 22 of the corresponding region through which a section of the electric power supply line passes, and this electronic geographic map 22 shows altitude information for the corresponding region. So, for example, on the electronic geographic map 22, only as an example, lines of height 22a, 22b, 22c are highlighted, which indicate areas of different height on the electronic geographic map 22.

To pair this electronic geographic map 22 with altitude information with the characteristics of the section of the power transmission line, a geographical map 23 must be added, from which follows the characteristic 23a of the section of the electric power supply line. By superimposing information on the geographical characteristics of the area from the map 23 on the height information from the electronic map 22, you can get a height profile 21.

Soil moisture should be considered as an influence factor for ground impedance. To do this, first from the database of the geographic information system is read an electronic geographical map 24, which indicates the structure of the soil. Such an electronic geographic map 24 gives the soil structure for various regions of the geographic map. For example, sandy soil may predominate in region 24a, watercourse is in region 24b, clay soil prevails in region 24c, and granite rock is in region 24d.

In order to obtain information about soil moisture, a weather map 25 is used for the corresponding area, which indicates the amount of rainfall over the past period of time in the corresponding area. So, for example, a large amount of precipitation fell in area 25a, for example 25 liters per square meter over the past four weeks, while in area 25b there was only a small amount of precipitation.

By combining the electronic map 24 with respect to the soil structure and the weather map 25 with respect to the amount of precipitation, an additional electronic map 26 can be generated that indicates the soil moisture for each location in the area in question. The greatest soil moisture is, for example, in region 26a, in which the watercourse is located, and also in region 26, in which a high amount of precipitation fell on clay soil.

Again, by overlaying with an electronic geographical map 23, which indicates the geographical representation of the corresponding area with the exact course of the section of the electric power supply line, it is possible to determine the characteristic 27 of soil moisture along the entire length of the section of the electric power supply line.

. Путем суммирования всех парциальных импедансов земли, вытекающих из описания 28 модели, можно, наконец, сформировать импеданс земли

по всей длине участка электрической линии электроснабжения.From the combination of the height profile 21 and the soil moisture characteristic 27, we can finally draw a conclusion regarding the earth impedance characteristic 28 along the length of the section of the electric power supply line and, thereby, generate a model description. From this description of the model it is possible, for example, for the point of the plot, which is located on the length L _i , to determine the value of the corresponding ground impedance

. By summing all the partial earth impedances arising from the description of model 28, we can finally form the earth impedance

along the entire length of the section of the electric power supply line.

In FIG. 2, a selection was made only for an example of relevant influence factors (altitude profile, soil moisture, earth structure). However, of course, any other influence factors that affect the earth's impedance can be taken into account. For example, the temperature characteristic in the soil could be determined based on air temperature, insolation, green cover, shading, and soil structure.

Based on FIGS. 3 and 4, it will be explained how the values of the influence factors or a description of the model are supplied to the distance protection device 11 (see FIG. 1).

Figure 3 shows a first exemplary embodiment of an electric distance protection device 30, which comprises a measured value recording device 31 and a control device 32. A communication device 33 is connected to the control device 32. The communication device 33 is connected via a communication connection to a remote data processing device 34, which may be, for example, a personal computer at a network control point.

The remote data processing device 34 has access to the data banks 35 and 36, which provide influence factor values for determining the model description. For example, the data bank 35 may be a meteorological data bank, and the data bank 36 is an integral part of the geographic information system. Of course, along with this, other data banks may be provided with data relating to other factors of influence.

The remote data processing device 34 receives from the data banks 35, 36 the position-dependent values of the influence factors, that is, the values with which, respectively, the geographical value of the location is associated.

According to the explanations with reference to Figure 2, the remote data processing device 34 generates a description of the model from here and transmits it to the distance protection device 30. In order to avoid unnecessary data traffic through the communication connection, such a transfer of the model description can be undertaken only when the model description is requested by the control device 32. This may preferably occur after a ground fault occurs in a portion 10 of the electrical power line.

4 shows a second embodiment of an electric distance protection device 40 with a measured value recording device 41 and a data processing device 42. The second exemplary embodiment of FIG. 4 differs from the exemplary embodiment of FIG. 3 in that here the calculation of the model description is performed by a non-remote data processing device. On the contrary, the control device 42 through the communication device 43 and the schematically shown communication network 44 can directly access the data banks 45 and 46 and obtain from them the values of influence factors. In this exemplary embodiment, the control device 42 itself calculates a description of the model. However, this can only be done in distance protection devices with relatively high-performance control devices.

Although the above description makes explicit references to the distance protection device, the invention may also provide software that implements the described method, which runs, for example, on the appropriate hardware of the device, for example, on a suitably executed personal computer.

Claims (12)

1. The method of determining the location of the grounding fault in the area (10) of the electric power supply line according to the principle of distance protection, and when a grounding fault occurs in the area
- the measured current value is determined, indicating the current flowing in the area (10),
- the measured voltage value is determined, indicating the voltage applied in the area (10),
- the measured value of the ground current is determined, indicating the current flowing in the area (10), and
- using certain measured values, the value of the location of the fault is calculated, which indicates the location of the grounding fault in the area (10), and this value of the location of the failure is formed using the impedance of the line of the area (10) and the ground impedance for the soil running along the area (10), and moreover, the value of the impedance of the earth, used to form the value of the location of the fault, is set dynamically,
characterized in that
- for the dynamic determination of the ground impedance value, a model description is used that takes into account at least two factors influencing the ground impedance and provides a characteristic of the ground impedance along the entire length of the plot (10). 2. The method according to claim 1, characterized in that
- at least two parameters from the following list are used as influence factors: air humidity, air temperature, air ionization degree, humidity of the corresponding soil, temperature of the corresponding soil, soil structure for the corresponding soil, distance from the site (10) to the soil. 3. The method according to claim 1 or 2, characterized in that
- at least two applied influence factors are measured and / or calculated. 4. The method according to claim 1, characterized in that
- at least two applied influence factors are obtained from at least one data bank (for example, 35), and at least one data bank (for example, 35) contains a comparison of the geographical location values with the corresponding values of the influence factors. 5. The method according to claim 4, characterized in that
- the values of the influence factors contained in at least one databank (for example, 35) are agreed in real time with the actual conditions. 6. The method according to claim 4, characterized in that
- the description of the model is formed through the selection of such values of the influence factors that are compared with those geographical values of the location along which the given section continues (10). 7. The method according to claim 4, characterized in that
- at least one data bank (for example, 35) is a geographic information system and / or a weather data bank. 8. The method according to claim 4, characterized in that
- the model description is generated by the remote data processing device (34) and provided from the remote data processing device (34) to the control device (32) of the distance protection device (30), which calculates the value of the fault location. 9. The method according to claim 8, characterized in that
- the model description is only then transmitted from the remote data processing device (34) to the control device (32) when the control device (32) requests a description of the model. 10. The method according to claim 9, characterized in that
- the control device (32) requests a description of the model after the occurrence of a ground fault in the area (10). 11. The method according to claim 4, characterized in that
- the distance protection device (40), which is located in the area (10), receives at least two applied influence factors from at least one data bank (for example, 35) and
- the device (42) for controlling the device (40) for distance protection, based on the accepted influence factors, forms a description of the model. 12. An electric distance protection device (11) for determining places of grounding failure in a section (10) of an electric power supply line, comprising
- a device (14) for recording measured values for recording measured values of current and voltage, as well as measured values of the ground current, which indicate the values of the current flowing in the area (10), and the voltage applied in the area (10), as well as the ground current, flowing along the plot, and
- a control device (15) that, using certain measured values, calculates the value of the fault location, which indicates the location of the ground fault in the section, and this fault location value is formed using the impedance of the section line (10) and the ground impedance for the soil running along the section ( 10),
characterized in that
the data processing device (15) is configured to implement the method according to any one of claims 1 to 8.

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