ARRESTER SYSTEM OF PARALLEL-CONNECTED ARRESTERS, AND METHOD FOR DETECTING FAULTS OF THE ARRESTERS

Abstract

An arrester system has at least two parallel-connected arresters, each with a sensor for determining leakage currents. A monitoring system is configured to detect faults at the arresters by comparing sensor data. The method for detecting faults at parallel-connected arresters includes comparing in particular the present measured values of the arresters and/or from sensors of the arresters. A fault is detected when there are deviations between measured values of different arresters. The arrester system is identified as fault-free when measured values of the arresters, in particular of all arresters, are substantially the same.

Claims

1-14. (canceled)

15. An arrester system, comprising: at least two arresters connected in parallel with one another; each of said arresters having a sensor for determining a leakage current; a monitoring system connected to said sensors and configured to detect faults at said arresters by comparing sensor data received from said sensors.

16. The arrester system according to claim 15, wherein said monitoring system is configured to detect the faults at said arresters by short-term measurements of said sensors, with the short-term measurements having a duration lying in a range selected from the group consisting of nanoseconds, milliseconds, seconds, and minutes.

17. The arrester system according to claim 15, wherein said monitoring system is configured to detect faults by comparison of individual currents across individual said arresters.

18. The arrester system according to claim 17, wherein said monitoring system is configured to detect faults by comparison of individual currents across each individual said arrester separately from other said arresters.

19. The arrester system according to claim 15, wherein said monitoring system is configured to detect faults by comparing a temperature of individual arresters with one another.

20. The arrester system according to claim 19, wherein said monitoring system is configured to detect faults by comparing the temperature of each arrester with all other arresters.

21. The arrester system according to claim 15, wherein the monitoring system comprises at least one data processing unit, a data memory unit, a data display unit, and a data transmission unit.

22. The arrester system according to claim 15, wherein said monitoring system is arranged spatially locally at a location of said arresters.

23. The arrester system according to claim 15, wherein said monitoring system is a spatially remote central control center or is connected to a spatially remote central control center by at least one connection selected from the group consisting of LAN, radio, and Internet.

24. The arrester system according to claim 15, wherein said arresters are configured for medium voltages and/or for high voltages.

25. A method for detecting faults at parallel-connected arresters or an arrester system, the method comprising: comparing current measurement values of the arresters or of sensors of the arresters; determining a fault when deviations are detected between measurement values of different arresters, and determining that the arrester system is fault-free when the measurement values of the arresters are substantially identical.

26. The method according to claim 25, which comprises identifying the arrester system as fault-free when the measurement values of all of the arresters of the arrester system are substantially identical.

27. The method according to claim 25, wherein the measurement values of the arresters comprise current values and/or temperature values.

28. The method according to claim 25, wherein the measurement values of the arresters are leakage current values and/or temperature values of individual arresters.

29. The method according to claim 25, which comprises measuring the measurement values by sensors on each arrester.

30. The method according to claim 29, which comprises measuring the measurement values with current sensors and/or temperature sensors of each arrester of the arrester system.

31. The method according to claim 25, which comprises jointly measuring the measurement values of all arresters.

32. The method according to claim 31, which comprises jointly measuring temperature values by at least one thermal imaging camera.

33. The method according to claim 25, which comprises comparing the measurement values of the arresters and/or of the sensors of the arresters that were measured in a short period of time selected from the group consisting of a period of time of nanoseconds, of milliseconds, of seconds and of minutes, or performing the method repeatedly and/or completing the method within a period of time selected from the group consisting of nanoseconds, milliseconds, seconds, and minutes.

34. The method according to claim 25, which comprises, upon detecting at least one faulty arrester, outputting a warning or information locally, or in a central control room, or on a hand-held device.

35. A method for detecting faults at parallel-connected arresters of an arrester system, the method comprising: providing an arrester system having: at least two arresters connected in parallel with one another; a monitoring system connected to receive measurement values related to the at least two arresters; comparing current measurement values of the arresters or of sensors of the arresters; determining a fault at the arresters when deviations are detected between measurement values related to different arresters, and determining that the arrester system is fault-free when the measurement values are substantially identical.

Description

[0028] The principle of an arrester system 1 according to the invention is shown schematically in FIG. 1. The arrester system 1 comprises at least two parallel-connected arresters 2, shown in the figure as three arresters 2 with the three-dot symbol . . . for further arresters 2. The arrester system 1 can alternatively also comprise only two arresters 2. The arresters 2 each have a sensor 3 for determining leakage currents. Further sensors can be comprised by one arrester 2, or a plurality of arresters 2 can comprise one sensor 3 which is designed to determine measured values resolved for each arrester 2, in particular individually. For the sake of simplicity, just one sensor 3 for each arrester 2 is shown in the drawings. The arresters 2 are formed for example as an air- or gas-insulated surge arrester, for example as a metal-oxide arrester with an insulator housing, in particular made of ceramic, silicone and/or composite materials, which for example has ribs on the outer periphery, or with a metal housing. Details of the arresters are not shown in the FIG. for the sake of simplicity.

[0029] Sensors 3 are designed for example in the form of shunt resistors, coils and/or optical sensors, in particular in the form of optical waveguides, at the various arresters 2. Individual currents thus can be measured via individual arresters 2. Alternatively or additionally, sensors 3 comprise and/or are temperature sensors which are designed to measure temperatures of individual arresters. Temperature sensors are, for example, thermistors, thermocouples, thermopiles, digital and platinum and/or silicon sensors, and/or thermal imaging cameras. Sensors such as thermal imaging cameras additionally allow a temperature measurement of a plurality of arresters simultaneously, with a resolution of the temperature for each individual arrester.

[0030] The arrester system 1 according to the invention, as is shown in the figure, comprises a monitoring system 4 which is designed to detect faults at arresters 2 in particular in short time intervals by comparing sensor data. Short time intervals are, for example, timespans of nanoseconds, milliseconds, seconds and/or minutes. Short-term measurement of the sensors 3, in particular measurements with a duration in the range of nanoseconds, milliseconds, seconds and/or minutes, allow a detection of faults at individual arresters 2 and/or at groups of arresters. The monitoring system 4 comprises at least one data processing unit which processes and evaluates the sensor data promptly, in particular immediately. A fault at an arrester 2 can thus be displayed and/or for example an alarm can be triggered immediately or at least promptly, i.e. within for example nanoseconds, milliseconds, seconds and/or minutes.

[0031] Arranged spatially locally at the location of the arrester 2, a detected fault at an arrester 2 is displayed by a, for example locally arranged, monitoring system 4, in particular at a monitor, a warning light and/or on hand-held devices, in particular for maintenance staff on site. The monitoring system 4 comprises for example a data memory unit which stores sensor data and allows a rendering of the temporal profile of measured values and/or sensor data. Data display units on site comprise, for example as previously described, monitors, warning lights and/or hand-held devices, in particular laptops, mobile phones and/or tablets. Data transmission units, in particular of wired design, for example LAN cables, and/or for radio, for example Bluetooth, W-Lan, mobile communication, are designed to transfer data from sensors, and/or the data processing and/or data memory unit, to data output units.

[0032] The monitoring system 4 comprises alternatively or additionally a spatially remotely arranged central control center. A detected fault at an arrester 2 is displayed for example by the monitoring system 4 remotely from the arrester 2, in particular many kilometers away, in the central control center or on hand-held devices, as described previously. A data connection between the central control center and the sensors 3 of the arresters 2 and/or a local data transmission unit allows the data transmission of the sensor data. A data processing and/or data memory unit, which stores sensor data and allows a rendering of the temporal profile of measured values or sensor data, is arranged on site or in the control room or the hand-held devices. Data are transmitted in particular in a wired manner, for example by LAN cable, and/or via radio, for example mobile communication. In the event of a fault of arresters 2, or a fault predicted from the data, maintenance staff are sent on site or maintenance staff on site are informed, in order to perform maintenance on and/or exchange the faulty arrester 2. Further measures can be taken centrally or in a decentralized manner, for example a disconnection and/or connection of equipment, electrical lines and/or current consumers, current generators, and/or power networks.

[0033] A fault of one or more arresters 2 is detected or identified by comparing in particular current measured values of the arresters 2 and/or of sensors 3 of the arresters 2. A measurement and/or a comparison of measured values of the arresters or the sensors of the arresters is performed in a short period of time or over long periods of time, for example over hours, days and/or years. A monitoring of the arresters and/or of sensors of the arresters can be performed briefly or over long periods of time, in particular continuously or at regular time intervals. A fault is present in the event of deviations between measured values of different arresters 2. Deviations within certain tolerances can be reliable, wherein furthermore deviations outside the tolerances, which in particular are predefined, serve for identification of faults of the arresters 2. The arrester system 1 is identified as fault-free in the event of substantially identical measured values of the arresters 2 and/or of sensors 3 of the arresters 2, in particular all arresters 2 or sensors 3.

[0034] The previously described exemplary embodiments can be combined with one another and/or can be combined with the prior art. For example, arrester systems can thus comprise arresters for medium and/or high voltages. Arresters are, for example, surge arresters for air- and/or gas-insulated applications. Sensors are comprised for example directly by the arrester and/or are arranged physically on the arrester, in particular coils and/or shunt resistors and/or temperature sensors in direct contact with the arrester, or spatially distanced from the resistor, in particular thermal imaging cameras. Data acquisition, data processing, data memory and/or data transmission devices can be arranged locally at the arrester or in the vicinity of the arrester, in particular for a plurality of arresters, and/or centrally or remotely decentralized, in at least one control room or computers, hand-held devices and/or the cloud.

LIST OF REFERENCE SIGNS

[0035] 1 arrester system [0036] 2 arrester [0037] 3 sensor [0038] 4 monitoring system