CN111416316A - Lightning arrester arrangement with aging determination unit - Google Patents

Abstract

The invention relates to a lightning arrester arrangement with a degradation determination unit (1), comprising a lightning arrester (VAR) and a degradation determination unit (1), wherein the degradation determination unit (1) has a first temperature measurement unit (S1) for detecting a thermal state of the lightning arrester (VAR), the degradation determination unit (1) further has a memory unit (MEM) and an evaluation unit (CPU), the memory unit (MEM) stores degradation data of an energy input corresponding to a type of the lightning arrester and a temperature characteristic relation, the first temperature measurement unit (S1) measures a temperature characteristic of the lightning arrester (VAR) corresponding to the energy input, and the evaluation unit (CPU) obtains the related degradation data according to the measured temperature characteristic corresponding to the energy input, and further determines a degradation degree of the lightning arrester (VAR).

Description

Lightning arrester arrangement with aging determination unit

Technical Field

The invention relates to a lightning arrester arrangement with a degradation determination unit.

Background

Overvoltage protection devices are used in many areas of electrical engineering to protect systems or equipment from overvoltage events. These overvoltage protection devices are usually connected in parallel with the system/device to be protected.

However, it is pointed out here that these overvoltage protection devices are subject to aging processes. An important factor in aging is the derivation of the overvoltage event itself.

Therefore, the function/performance of the overvoltage protection device should be checked from time to time.

In many areas, overvoltage protection devices are no longer readily accessible after installation. In this connection, the use of overvoltage protection devices in offshore wind turbines or in control cabinets should be mentioned.

Testing is often time consuming and can result in loss of protection, at least temporarily.

Therefore, in the past, solutions to this drawback have been sought.

It is known from the prior art, for example from DE 112010004351T 5, to provide a monitoring device which can detect a voltage relative to a threshold voltage, wherein the number and frequency of the threshold voltages and other characteristics of exceeding the threshold voltages can be evaluated.

DE 102015014468 a1 discloses a multistage cooperative overvoltage arrester circuit with at least one coarse protection in the transverse branch and one fine protection in the longitudinal and transverse paths. The monitoring device is assigned to two protection elements. The damage is determined by means of the current values and the characteristic data.

An overvoltage protection device is known from DE 102010038208 a 1. The temperature of the overvoltage protection device is monitored by a temperature variable resistor.

However, all the mentioned prior art circuits have in common that the actual damage behaviour is only incompletely detected, so that a clear dependency between the measured electrical signal and the actual damage to the lightning arrester cannot be clearly given, and that a safety margin has to be planned in order not to give a false sense of safety to the user.

The above circuit assumes that the discharge events are carried out at large time intervals, so these events can be approximately interpreted as a single event. However, if the events occur continuously, this assumption is no longer true.

Disclosure of Invention

Starting from the above, it is an object of the invention to provide an improvement with regard to the determination of the aging, in order to be able to better predict the remaining service life.

This object is achieved by a lightning arrester arrangement with an aging determination unit according to claim 1. Further advantageous embodiments form the subject matter of the dependent claims, the figures and the description.

Drawings

The invention is explained in more detail below with reference to the drawings. The illustrated diagram is:

fig. 1 is an exemplary temperature profile of an arrester for different discharge events at an ambient temperature of 0 ℃;

fig. 2 is an exemplary temperature profile of the arrester for different discharge events at an ambient temperature of 20 ℃;

fig. 3 is an exemplary temperature profile of the arrester for different discharge events at an ambient temperature of 80 ℃;

FIG. 4 is an exemplary degraded synthetic characteristic curve for the introduction of thermal energy;

fig. 5 shows a structure of a lightning arrester device having an aging determination unit according to the design of the present invention.

List of reference numerals

1 aging determination unit

VAR lightning arrester

S1 first temperature measuring unit

MEM memory device

CPU evaluation unit

DIS local display

I/O interface

S2 second temperature measuring unit

S3 humidity measuring unit

A PE peltier element.

Detailed Description

The invention will be explained in more detail below with reference to fig. 1-4. It should be noted that the embodiments describe different aspects, which can be used alone or in combination. That is, any aspect may be used with different embodiments of the invention, unless explicitly shown as a pure alternative.

Furthermore, for simplicity, only one entity is generally referenced below. The invention may also have multiple related entities, unless explicitly stated otherwise. In this regard, the use of the terms "a", "an" and "the" are to be construed as merely indicating the use of at least one entity in a simple embodiment.

In the methods described below, the various steps of the methods may be arranged and/or combined in any order, unless otherwise explicitly stated in the context. These processes may also be combined with each other, unless explicitly stated otherwise.

A specification with numerical values should not generally be understood as an exact value, but also includes a tolerance of +/-1% to +/-10%.

Reference to a standard or specification or regulation should be understood as a reference to a specification or regulation that applies at the time of registration and/or (if priority is required) applies at the time of priority registration. However, this should not be construed as a general exclusion of the applicability to subsequent or alternative or specifications or regulations.

It is well known that the performance, aging and lifetime of overvoltage protection devices depend to a large extent on the thermal boundary conditions under which the devices operate. The current temperature of the arrester used there is influenced by external environmental conditions and self-heating.

The occurrence of an overvoltage event leads to a different high energy conversion in the overvoltage arrester (arrester for short), which is stored quasi-adiabatically in the arrester, i.e. heats it, because of the short duration of the pulses, which are typically about 1 μ s to 1000 μ s. Furthermore, due to an actual overvoltage event (e.g., a lightning strike), a series of irregular pulses of different heights and lengths may occur in a few seconds. Even in the case of such events, it can be assumed that no relevant amount of thermal energy is released into the environment in an event lasting a few seconds and therefore the system can still be considered adiabatic.

Such pulse durations may also occur in standard test pulses, for example as described in IEC 61643-32: 2017 (or withdrawn IEC 61643-1: 2005). For example, a surge voltage pulse of 1.2/50 μ s is an event corresponding to a rise time in the range of a unit of microseconds, a test pulse of 8/20 μ s corresponds to a surge current event of about 50 μ s, and a test pulse of 10/350 μ s corresponds to a discharge event of, for example, about 1000 μ s.

After an overvoltage event occurs, the arrester cools. This process is essentially continuous and may take several minutes.

The arrester therefore represents a thermal integrator with a large time constant, which can convert the heat input caused by an overvoltage into a simple heating-cooling curve, even with very complex shapes.

Which maximum temperature the arrester reaches in the process during the whole process depends on the one hand on the energy converted internally and on the other hand on the initial temperature, i.e. the temperature at which the discharge event starts.

Here, the initial temperature is also determined by the ambient temperature.

In some cases, where overvoltage events can briefly follow each other, heat dissipation is usually not yet complete, so that the initial temperature of the arrester is determined by the residual heat of the last discharge process in addition to the ambient temperature.

From the recording of the discharge events of the arrester and taking into account the climatic boundary conditions and their performance characteristic values, the extent of damage or ageing of the arrester can be determined.

The energy input for the discharge process can be calculated here by time-resolved measurement of the current and voltage profiles.

If the state of the system at the beginning of the discharge event is known, conclusions can be drawn about the VAR status of the arrester.

Taking the varistor as an example, it is clear that the varistor reaches the maximum temperature earlier in the case of an ambient temperature of 80 ℃ than in the case of an ambient temperature of 20 ℃.

A similar relationship is also contemplated for spark gaps whose extinguishing process is based on arc cooling using hard gaseous plastics such as Polyoxymethylene (POM).

The invention therefore proposes to continuously (continuously or at defined time intervals) thermally monitor the arrester VAR and to compare the determined temperature data with a corresponding experimentally determined thermal derating characteristic field of the arrester.

With each relevant temperature event, the arrester will reach the end of its service life in the derating characteristic curve field.

Thus, the current state and/or "statistical remaining life" may be determined at each point in time.

In order to ensure that the electrical data processing takes place after an overvoltage protection event without an operating voltage being applied, a peltier element PE can additionally be mounted in thermal contact on the arrester, so that the evaluation unit can be supplied with voltage by the heat of the arrester.

Alternatively or additionally, the operating energy for the evaluation unit CPU can also be obtained from the pulse events by means of an inductively coupled system.

The energy may be stored capacitively (e.g., in a super capacitor).

The arrester VAR, that is to say the spark gap, as well as the varistor and the gas arrester, is subject to temperature-dependent aging. In the case of a spark gap, it can be assumed that the ambient temperature and the corresponding discharge event lead to a relevant degradation, and in the case of a varistor, the ambient air humidity also has an effect.

Without being limited to generality, the temperature-dependent degradation characteristic field (determined by the manufacturer, for example) can be determined under different environmental conditions (temperature and air humidity) with the use of a specification pulse (8/20 μ s, 10/350 μ s), which is applied under corresponding boundary conditions until the arrester breaks down. From this, a characteristic field can be determined for a type (or batch). In this case, the temperature at the lightning conductor under test is measured continuously (continuously or at defined time intervals). After each pulse or after a series of pulses, a characteristic value of the arrester is determined, which characteristic value allows progressive damage to be detected.

For example, leakage current at test voltage, voltage change at test current (1 mA point), insulation resistance and change in arc voltage can be used as typical characteristic values of the arrester.

From these characteristic values it is possible to determine from when the arrester (before the final damage) should be considered as the relevant damage (end of life).

Different limit values can define different damage levels, from which different warning levels can be derived in later operation.

By means of continuous temperature measurements of the arrester, a heat integral can be determined, which is associated with the damage of the arrester up to its (determined) service life.

The impulse load under different environmental conditions may follow the usual test scenario of lightning arresters-as it is determined by the respective standards, e.g. IEC 61643-11: 2011, etc.

In this case, a "full operation test" can be carried out with a predetermined rated leakage current In until the lightning arrester is destroyed. Instead of a product-specific In value (nominal current value), an increased or decreased In value may also be used.

Depending on the type of arrester, it may be useful to determine which type of impulse load with the same external temperature profile would result in higher internal damage, since the temperature measurement cannot distinguish between e.g. short high current pulses and long low current pulses.

In the worst case, if questionable, experiments should be conducted to determine the reference characteristic field of the pulse shape with a higher probability of damage.

In another approach, the empirical data is determined by long and short pulses. The average expected value and worst case can then be determined.

In order to empirically determine the aging data, a pulsed load is preferably used continuously (continuously or at defined time intervals). This can be performed on the basis of a specification test (regulation) at the supply voltage, for example at a known critical angle, so that in the sense of a "worst-case analysis" it is always in the safe region. The test should continue until the arrester is damaged. The temperature measured at the arrester for each discharge process has a trend profile as outlined in fig. 1-3.

Fig. 1 shows an example of heating and cooling of the lightning arrester at an ambient temperature of T0 ═ 0 ℃. The curve K1 rises to the first maximum temperature Tm,1 and then converges to zero again.

If the discharging event is repeated a number of times until the arrester is destroyed, a frequency n is obtained at which the arrester can cope with the temperature curve.

The area F1 under one curve thus forms a relevant measure for the damage occurring in the arrester.

The same relationship applies to the remaining three curves K2, K3, K4, wherein tests have shown that the frequency with which the arrester should cope with this temperature curve is lower. Curve K5 represents a temperature rise curve which has caused unacceptable damage to the arrester when it first appears.

After examining the characteristic field of the ambient temperature of T0 = 0 ℃, it can be known which frequency of thermal events would lead to the end of the service life of the arrester if the ambient temperature is 0 ℃.

In this case, nonlinear damage progresses, for example "a large discharge event at high temperatures can lead to disproportionate damage", which is characterized by experimentally determined characteristic curve regions.

For example, the heating curve of shape K1 may be repeated 10000 times, the heating curve of shape K2 1000 times, the heating curve of shape K3 100 times, and the heating curve of shape K4 only 10 times.

In order to obtain a complete picture of the aging of the arrester, a corresponding characteristic field must be generated for further ambient temperatures.

Fig. 2 shows an exemplary possible characteristic field for an ambient temperature T0 = 20 ℃.

Since the ambient temperature is already higher than in fig. 1, the dynamic heating curve also starts from this higher temperature level T0 and returns there again after the heat has been completely dissipated/cooled. On the other hand, the maximum allowable temperature is specific to the arrester and is independent of the temperature. The maximum allowable temperature is thus essentially the same as in fig. 1, since it already shows the limiting characteristics of a damaged arrester. Thus, at least the maxima of the curves K4 and K5 remain substantially the same.

It is also clear from fig. 3 that at significantly elevated ambient temperatures (here T0 = 80 ℃), the range of additional dynamic heating allowed by the arrester becomes smaller and smaller.

Thus, a unique reference characteristic field can be determined for each arrester type, so that a working area can be defined for the arrester type and limit values can be set for evaluating the permissible environmental conditions.

Information reflecting the current state of the arrester or the protection capability of the installed arrester can thus be derived at a known/measured ambient temperature (T0) at the installation location.

Furthermore, a correlated damage integral may be calculated for each measured discharge event/temperature distribution event based on the starting temperature (area under the dynamic curve F1).

The accumulated damage score may more accurately reflect the continued damage condition of the arrester.

This data can be used for further evaluation and information processing.

In summary, a degradation profile can be created from all determined dynamic temperature rise curves and the areas under the respective curves, which can be regarded as the relevant impairment integrals.

To this end, an exemplary degradation map for the arrester type is given in fig. 4. Here, q (j) corresponds to the input thermal energy, showing a measure of the primary damage q (j) of the arrester VAR caused by the heat input, which is approximately proportional to the area of the curve under the temperature characteristic curve domain.

The sum of all area integrals is related to the total derivative integral (sum of all derivatives), so that a state and service life prediction can be derived from the temperature-dependent degradation characteristic field determined experimentally for each arrester type (taking into account the air humidity in some cases for the varistor).

These prediction values can be used continuously and in particular when predefined limit values for the status report of the arrester are reached.

All known methods can be used for status and/or alarm reporting. For example, the status and/or alarm reports may be provided via a local (mechanical and/or optical and/or electronic) display DIS and/or via an interface I/O. Interface I/O may also be used for remote monitoring, for example. Such an interface I/O may for example be designed to be readable by an RFID on the lightning arrester. Here, the pulse shape (8/20 μ s and 10/350 μ s) or any overpressure event comes from practical use without having an impact on the damage analysis, since the overall external temperature profile depends only on the internal energy conversion due to the high time constant of the system. This means that any discharge event (burst, 1.2/50 mus 8/20, 4/20, 10/350 mus, 10/1000 mus, any pulse waveform) occurring on the surface of the arrester VAR results in a higher or lower heating and heat dissipation curve. After any event, the method compares the heating and heat dissipation curves that have occurred with the curves of the reference characteristic field, so that the damage/ageing of the arrester can be derived regardless of the event.

According to the method, different arrester status data can be determined and used for evaluation and customer information.

If the current arrester temperature is known (time resolved measurement of the arrester temperature), it can be determined from the speed of change whether there is a change in the ambient temperature (slow change-typically in the range of minutes) or a discharge event (fast change-typically in the range of seconds).

The number of detected discharge events (rapid changes) can then be added and provided as information.

In addition, each discharge event energy may be determined, e.g. by means of the differential integral I t. From this the degradation level of the arrester VAR can be determined. Alternatively or additionally, the degradation of the arrester VAR can be determined from the current ambient temperature and from the energy converted in the arrester according to a dynamic arrester temperature curve after the derivative (derivative integral of the ambient temperature correction).

From the information on the deterioration of the varistor, the user can receive information on the state of deterioration and/or on the prediction of the service life and/or on the lightning arrester to be replaced and/or on whether the protection is sufficiently ensured or how much possibility is available to obtain and provide a full protection.

Furthermore, the current maximum discharge capacity depends, for example, on the ambient/self temperature.

Furthermore, ambient temperature conditions (slow changes) can be identified and relevant data about the environment and possible ageing of the piezoresistors can be gathered from the current ambient temperature. This information can be provided to the user if the ambient temperature is high at all times. The ambient temperature can also be detected, for example, at the installation location of the arrester VAR. This information may also be provided to the user if the temperature exceeds the product specification (max/min temperature).

If the maximum temperature of the arrester is known after the occurrence of a discharge event (rapid temperature rise), the number of times a given limit temperature is exceeded can be counted as a damage event. This information may be provided as appropriate. Also, once a certain number of damage events are reached, the arrester can be considered to be sustainably damaged. This information may also be provided in a suitable manner.

According to the present invention, there is provided a lightning arrester device having an aging determination unit 1.

The arrester can be, for example, a varistor or a spark gap or a gas arrester, or another electrical component (semiconductor component/semiconductor switching element) which ages as a result of a conductor event. Fig. 5 shows an example structure as a lightning arrester device.

The aging determination unit 1 has a first temperature measurement unit S1 that detects the thermal state of the arrester VAR. The first temperature measuring device S1 may be, for example, a PT100 sensor, a thermally variable resistor (e.g., a positive temperature coefficient resistor or thermistor) in a measuring bridge, a peltier element, or the like.

Alternatively or additionally, the first temperature measuring unit S1 may be a temperature radiation sensor, such as an infrared sensor, which may also be spaced apart from the arrester VAR.

Furthermore, the aging determination unit 1 has a memory unit MEM and an evaluation unit CPU.

The memory unit MEM may be, for example, a semiconductor memory. The evaluation unit CPU may be a microprocessor, a microcontroller (with built-in memory MEM), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), or the like.

The memory unit MEM can be programmed in such a way that it contains the type of aging data associated with the temperature characteristics as a function of the energy input in the same type of arrester. Data can be stored in a read-only manner to make tampering more difficult.

The first temperature measuring unit S1 is arranged to measure the temperature characteristics for determining the energy input in the arrester VAR.

The evaluation unit CPU is configured to: the degree of ageing of the arrester VAR is determined using the temperature characteristic determined using the measured energy input and the type-dependent ageing data stored in the memory means MEM.

It should be noted that the arrester VAR can be designed to be pluggable, for example. The arrester VAR, for example, can then also have a memory unit MEM, which can be connected to the evaluation unit CPU via a suitable interface for reading data therefrom.

However, it can also be provided that only one reference, for example UR L, is provided on the arrester itself, by means of which data relating to the arrester VAR can be loaded into the memory unit MEM.

Without being limited to generality, it can be provided that, if the determined aging exceeds a certain value, the arrester VAR can be protected against overload by a switching device and/or a warning message can be output. In this case, the protection can be achieved by opening or short-circuiting the arrester VAR.

Without being limited to generality, it may also be provided that the aging determination unit 1 also has a local display DIS, which displays the determined aging value, for example a color display, such as an L CD display or an electronic paper (EPaper) display, etc., may be provided.

Without being limited to generality, it may also be provided that the aging determination unit 1 further has AN interface I/O, through which a determined aging value CAN be provided, so that remote diagnosis and downloading of data related to the piezoresistors CAN be made.

Without being limited to generality, the aging determination unit 1 may determine the predicted remaining useful life based on the frequency and number of measured energy inputs corresponding to the determined temperature characteristics.

In order to be able to provide more accurate results, it is possible to determine not only the temperature of the arrester VAR but also the temperature of the surroundings. For this purpose, the aging determination unit 1 may also have a second temperature measurement unit S2 for ambient temperature t0 measurement, the evaluation unit CPU being able to determine the extent to which the arrester VAR has aged using the measured temperature characteristic corresponding to the energy input and the type-dependent aging data and the measured ambient temperature. If the determined aging exceeds a certain value, the arrester VAR is switched off by the switching device, or short-circuited by the switching device and/or output locally, for example on the display DIS and/or output via the interface I/O as a warning message.

The second temperature measuring unit S2 may be, for example, a PT100 sensor, a thermal variable resistor (e.g., a positive temperature coefficient resistor or a thermistor) in a measuring bridge, a peltier element, or the like.

Without being limited to generality, it can also be provided that the evaluation unit CPU, after having obtained the temperature characteristic corresponding to the measured energy input and the aging data of the arrester (VAR) type, determines, by means of the current ambient temperature measured by the second temperature measuring device S2, the size of the next maximum discharge event at that point in time that does not destroy the arrester VAR. The limit value (safety threshold) for the next maximum discharging event that does not damage the arrester VAR can be provided locally via the display DIS and/or remotely via the interface I/O. If the limit value set by the user is exceeded, a corresponding warning is issued. The limit values may be input locally and/or remotely (e.g. using an I/O interface) on the aging determination unit 1.

Furthermore, it may be advantageous if other influencing variables can also be measured. For example, for some arrester VARs, humidity is also important. The aging determination unit 1 can therefore also have a humidity measuring device S3, wherein the evaluation unit CPU determines the degree of aging of the arrester VAR using the measured temperature behavior corresponding to the energy input and the aging data relating to the type and the measured ambient humidity, wherein, when the determined aging exceeds a danger value, the arrester VAR is disconnected by a switching device or short-circuited by a switching device and/or a warning message is output locally, for example on a display DIS, and/or via an interface I/O.

The moisture measuring device S3 may be, for example, a capacitive or resistive moisture meter.

Without being limited to generality, the memory unit MEM may contain type-dependent aging data for energy input-dependent temperature characteristics in the same type of arrester, wherein the stored type-dependent aging data is determined experimentally.

The invention now makes it possible to record the actual damage behaviour more completely. Thus, the previous safety margin may be reduced and the safety and usability of the device may be improved.

This is achieved in particular in that discharge events occurring at short intervals can be evaluated more precisely.

The arrester arrangement with the aging determination unit 1 can be provided as an integrated device or insertable set, wherein the arrester VAR can be inserted, for example, into a base device or a base.

In terms of temperature characteristics, temperature profiles in the sense of continuous, periodic or event-controlled measurements can be specified. For example, a certain threshold may be used as an event that triggers one or more measurements. However, the measured temperature gradient may also be used as an event of the temperature characteristic.

The aging data may be determined, for example, using the methods described below.

Determining the type of the arrester VAR and setting environmental parameters, placing the determined arrester in a set environment (e.g. a certain temperature and/or a certain humidity), and applying a predetermined test pulse.

The energy inputs (corresponding to the test pulses) are then summed as a function of the set environmental parameters. In the case of identical test pulses, the number of test pulses can alternatively or additionally be increased; until a certain aging state is reached, for example, destruction or the occurrence of a predetermined leakage current.

In a simple manner, a characteristic curve field can be created for different environmental parameters for which the method is to be performed.

Claims (18)

1. A lightning arrester arrangement with an aging determination unit (1), comprising a lightning arrester (VAR) and an aging determination unit (1), characterized in that the aging determination unit (1) has a first temperature measurement unit (S1) for detecting a thermal state of the lightning arrester (VAR), the aging determination unit (1) further has a storage unit (MEM) in which aging data of an energy input corresponding to a type of lightning arrester is stored in relation to a temperature characteristic, and an evaluation unit (CPU) which measures the temperature characteristic of the lightning arrester (VAR) corresponding to the energy input, the evaluation unit (CPU) obtains the relevant aging data from the measured temperature characteristic corresponding to the energy input, and determines an aging degree of the lightning arrester (VAR).

2. A arrester arrangement according to claim 1, characterized in that the arrester (VAR) can be protected from overload and/or a warning message can be output by means of a switching device when the determined ageing exceeds a certain value.

3. A lightning arrester arrangement according to claim 1, characterized in that the aging determination unit (1) further has a local Display (DIS) displaying the determined aging degree value.

4. A lightning arrester device according to claim 3, characterized in that the local Display (DIS) is an electronic paper display.

5. A lightning arrester device according to any of the preceding claims, characterized in that the aging-determining unit (1) further has an interface (I/O) through which the determined aging value can be provided.

6. A lightning arrester device according to claim 5, characterized in that the interface (I/O) is a wired and/or wireless interface.

7. An arrester arrangement according to any of the preceding claims, characterized in that the aging determination unit (1) determines the predicted remaining service life on the basis of the frequency and the number of temperature characteristics corresponding to the measured energy input.

8. A arrester arrangement according to any of the preceding claims, characterized in that the aging determination unit (1) further comprises a second temperature measurement unit (S2) for ambient temperature measurement, the evaluation unit (CPU) using the measured temperature characteristic corresponding to energy input and the type-related aging data and the measured ambient temperature to determine the degree of aging of the arrester (VAR), wherein: when the determined aging exceeds a certain value, the arrester (VAR) is switched off by means of a switching device or short-circuited by means of a switching device and/or a warning message is output.

9. A arrester arrangement according to any of the preceding claims, characterized in that the aging determination unit (1) further has a humidity measurement unit (S3), the evaluation unit (CPU) using the measured temperature characteristic corresponding to the energy input and the type-related aging data and the measured ambient humidity to determine the degree of aging of the arrester (VAR), wherein: when the determined degree of ageing exceeds a certain value, the arrester (VAR) is switched off and/or a warning message is output.

10. An arrester device according to any of the preceding claims, characterized in that the arrester is selected from the group consisting of piezoresistors, spark gaps, gas arresters.

11. A lightning arrester device according to any of the preceding claims, characterized in that the first temperature measuring unit (S1) is a platinum measuring resistor and/or a peltier element.

12. A lightning arrester device according to any of claims 1-10, characterized in that the first temperature measuring unit (S1) is a temperature radiation sensor.

13. A arrester arrangement according to any of the preceding claims, characterized in that the aging determination unit (1) further has a second temperature measurement unit (S2) for ambient temperature, the evaluation unit (CPU) determining the magnitude of the next maximum discharge event that does not damage the arrester by means of the current ambient temperature measured by the second temperature measurement unit (S2) after using the measured temperature characteristic corresponding to the energy input and the aging data corresponding to the arrester (VAR) type.

14. An arrester arrangement according to claim 13 wherein a safety threshold is set in response to the next maximum discharging event providing no damage to the arrester, and a corresponding warning is issued if the next discharging event exceeds the set threshold.

15. A arrester device according to any of the preceding claims, characterized in that a switching device protects the arrester (VAR) from overload by opening or short-circuiting.

16. An arrester arrangement according to any of the preceding claims, characterized in that the memory unit (MEM) contains temperature characteristics corresponding to energy input in the same type of arrester and from this determines ageing data corresponding to the type, wherein: the corresponding relation between the aging data and the type is determined through experiments.

17. A lightning arrester device according to any of the preceding claims, characterized in that the temperature characteristic corresponding to the energy input is a temperature profile with at least two measured values.

18. A method of determining aging data for a lightning arrester type, the method comprising:

determining a arrester (VAR) type:

setting environmental parameters: the environmental parameter has at least a determined temperature and/or a determined air humidity;

-applying a test pulse to the arrester (VAR);

recording energy input and/or test pulse number according to environmental parameters;

the number of test pulses is increased until a certain state of ageing is reached.

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