Device for synchronizing partial discharge monitoring system

Abstract

To provide a new device and method for generating and providing a synchronization signal for identifying partial discharge in a GIS.SOLUTION: A device (100) for providing a synchronization signal for identifying a partial discharge in a GIS, comprises: an AC reference switch device (20) including a plurality of inputs for inputting a plurality of synchronization signals from a plurality of sensors, the AC reference switch device (20) including means for selecting an input from among the plurality of inputs on the basis of presence of a synchronization signal; and an AC inverter (30) for providing a power-synchronization signal on the basis of the synchronization signal provided by the AC reference switch device (20).SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to the synchronization of partial discharge detection in high voltage equipment such as gas insulated stations (GIS). [Background technology]

[0002] Damage to the GIS can be caused by partial discharges which can result from a variety of origins, for example the presence of protrusions and / or particles and / or any kind of unevenness on or within the interior surface of the GIS.

[0003] Such partial discharges can be detected by a variety of devices, for example, optical or acoustic or ultra-high frequency (UHF) devices.

[0004] All these detections require synchronization with a high voltage (usually 50 Hz or 60 Hz) to allow identification of the nature of the defect. However, such synchronization is not always available.

[0005] There is a technical problem to be solved regarding improving the synchronization of partial discharge detection involved in UHF-based methods, and in particular the problem of finding a method and device that provides synchronization that allows identification of any partial discharge within a GIS.

[0006] Furthermore, synchronization systems for detecting partial discharges are complex. For example, a UHF partial discharge detector requires a power signal and an acquisition signal. Generating both signals is complex and increases the number of connections.

[0007] Therefore, there is another technical problem to be solved related to finding a simplified system and method for synchronization of partial discharge detection by UHF-based methods.

[0008] Another problem is that the primary voltage source on which any synchronization is based may be measured at multiple locations, and the sensors used for this may have different characteristics and may not be compatible with long signal links.

[0009] Therefore, another technical problem to be solved relates to finding a simplified system and method that allows detection-based synchronization at multiple locations.

[0010] In this invention, a new device is proposed to manage these multiple voltage sources and distribute them safely in a partial discharge monitoring system. Summary of the Invention

[0011] To solve one or more of the above problems, the present inventors have discovered a new device and method for generating and providing a synchronization signal for identifying partial discharges in a GIS.

[0012] The present invention first provides: an AC reference switch device comprising a plurality of inputs for receiving a plurality of synchronizing signals from one or more measurement devices, for example an HV voltage transformer, the switch device comprising means for selecting an input from among the plurality of inputs based on the presence of a synchronizing signal; an AC inverter for providing a power and synchronization signal based on at least the synchronization signal provided by the AC reference switch device; The present invention relates to a device for providing a synchronization signal for identifying partial discharges in a GIS, comprising:

[0013] The AC inverter may comprise a transformer and / or at least one of a microcontroller and / or phase compensation means.

[0014] In a device according to the invention, the AC reference switch device may include a test signal input, and a priority rule may be established in the AC reference switch device, whereby the test signal takes priority over other signals from one or more measurement devices.

[0015] The AC reference switch device may comprise a power supply.

[0016] The AC inverter may include a power supply, and the AC inverter provides a power and synchronization signal based on the synchronization signal provided by the AC reference switch device and the power supply.

[0017] The present invention also provides a device for providing a synchronization signal according to the invention, a plurality of partial discharge acquisition units, each one comprising a power input and a synchronization input both connected to the output of the AC inverter, and one or more signal inputs for receiving one or more signals from one or more partial discharge sensors; The present invention relates to a device for identifying partial discharges in a GIS, comprising:

[0018] One or more of the partial discharge acquisition units may be connected to one or more partial discharge sensors, which may include, for example, one or more optical sensors and / or acoustic sensors and / or UHF sensors.

[0019] The present invention also provides - a metal tank filled with gas and equipped with at least one primary conductor; one or more sensors for detecting partial discharges, at least one measuring device for detecting HV signals in said primary conductor; a system according to the invention, wherein each measuring device is connected to an input of an AC reference switching device and each sensor is connected to an input of a partial discharge acquisition unit; It is related to GIS.

[0020] The one or more sensors may include one or more optical and / or acoustic and / or UHF sensors, and / or the one or more measuring devices may include one or more HV voltage transformers.

[0021] The present invention also provides one or more measurement devices providing a synchronization signal to one or more inputs of the plurality of inputs of the AC reference switch device; the AC inverter providing a power and synchronization signal to each of the plurality of partial discharge acquisition units; The partial discharge acquisition unit synchronizes the partial discharge signal with the synchronization signal. The present invention relates to a method for detecting partial discharges in a GIS.

[0022] A test signal may be provided to the input of the AC reference switch device, the test signal being selected by the AC reference switch device, for example, during a test phase of the GIS. [Brief explanation of the drawings]

[0023] [Figure 1] 1 shows a single line diagram of an example of a high voltage installation to which the present invention can be applied. [Figure 2] 1 shows an example of a switch device according to the present invention. [Figure 3A] 1 illustrates an embodiment of an AC inverter according to the present invention. [Figure 3B] 3 illustrates one embodiment of a signal provided by an AC inverter according to the present invention. [Figure 4] 1 shows an example of a device according to the present invention for providing a synchronization signal for identifying partial discharges. [Figure 5] 1 shows an example of a partial discharge acquisition unit according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] An example of a high voltage facility 2 to which the present invention can be applied is shown in FIG.

[0025] The high voltage installation 2 comprises an HV line with at least one primary conductor 5, and the high voltage installation 2 may be provided with a number of circuit breakers 2, 4, 6...

[0026] The high voltage installation 2 is also provided with a number of measuring devices 10, 12, 14, e.g. voltage transformers, which measure the HV signal at a number of measuring points (e.g. at a frequency of 50 Hz) and reduce the detected voltage to a value e.g. below 100 V.

[0027] The high voltage installation 2 is also provided with a number of partial discharge (PD) sensors (not shown in the drawings), such as optical and / or acoustic and / or UHF sensors, for detecting the presence of partial discharges based on other methods, e.g. optical, acoustic or UHF methods.

[0028] Partial discharges generate frequencies in the range of, for example, 100 MHz to 2 GHz.

[0029] The outputs of the various measurement devices 10, 12, 14 are provided to a switch device 20, one embodiment of which is shown in Figure 2. The switch device 20 has a number of voltage inputs 10, each for receiving an input from one of the measurement devices 10, 12, 14. i , 12 i , 14 i These inputs are compatible with multiple sensors and sensor technologies.

[0030] An output 24 of the switch device 20 provides a synchronization signal 25 .

[0031] The switch device 20 comprises signal detection and switching means 22 for selecting one of the inputs at which a synchronising signal is actually detected, any of the measuring devices 10, 12, 14 may be disconnected from the HV signal at any time by a circuit breaker located between the HV line and the measuring device. The partial detection system therefore cannot rely on a particular measuring device to receive the synchronising signal, and for this the means 22 checks whether a signal is actually provided to the input to which the output 24 is connected via the switch device 20. If there is no voltage at the first input, the switch device 20 switches to the next one, or more generally, if there is no voltage at one of the inputs (n), the switch device 20 switches to another input, for example the next input (n+1), or to the first input if there is no next input.

[0032] Some inputs 10 i , 12 i , 14 i are electrically isolated from each other, making it possible to obtain at least one synchronization signal in all configurations of the primary equipment.

[0033] First Input Channel 10 i may be the test signal injection input that takes priority over others.

[0034] A test signal is provided to the system during the test phase and can have a frequency different from the network frequency, depending on the available test signal generator. The test signal may be incompatible with the measuring devices 10, 12, 14, particularly due to its strength, and may be switched off during the test. However, the PD sensors are still active, and their signals (resulting from partial discharges during the test) must be synchronized with the test signal during the test phase. For this purpose, the switch device preferably has an input for this test signal that takes priority over other inputs. The device according to the present invention therefore makes it possible to synchronize the PD signals during the test phase.

[0035] Switch device 20 is also provided with an input voltage from a power supply 23 .

[0036] The synchronization signal provided by switch device 20 is fed to AC inverter 30 which generates both power and a synchronization signal at its output 34 based at least on synchronization signal 25 .

[0037] One embodiment of an AC inverter 30 is shown in Figure 3A. The AC inverter 30 comprises a transformer 32 fed by transistors H1, H2 connected downstream from a microcontroller 36, which is fed by a synchronization signal 25, but preferably also by a phase signal 27 as described below.

[0038] The microcontroller 36 controls the transistors H1 and H2 to be alternatively conductive, thereby generating a supply-sync signal that is alternatively positive and negative at the input frequency of the synchronization signal 25. A phase shift may be introduced by the transformer 32, but the microcontroller 36 can take this into account by means of the phase compensation input 27, so that the output signal is in phase with the input synchronization signal 25.

[0039] An example of the output signal of the AC inverter is shown in FIG. 3A and is also shown in FIG. 3B.

[0040] The AC inverter 30 is also provided with an input voltage from a power source 33. The inverter 30 generates an AC power signal 29 based on this input voltage and the AC signal input 25.

[0041] 4, each of a plurality of acquisition units 40, 42... is provided with an output signal 29 from the AC inverter 30 of the device 100 according to the present invention for providing a synchronization signal. The output signal 29 from the AC inverter 30 (including both the power and synchronization signals) can be distributed to the various acquisition units 40, 42 via wiring 37 (preferably a single wire), which can then be distributed to substations.

[0042] Each of the acquisition units 40, 42... may also be supplied with signals from one or more PD sensors, eg one or more UHF antennas 50, 52, 54, 60, 62, 64, that detect partial discharges in the GIS of FIG.

[0043] The output of each of the acquisition units 40, 42... may be provided to a computer or microprocessor 70 programmed to analyze the output signals from the acquisition units 40, 42... and classify partial discharges according to their origin, for example, from the presence of protrusions and / or particles and / or any kind of inhomogeneity on or within the interior surface of the GIS. One embodiment of the acquisition unit 40 is shown in FIG. 5. The other acquisition units 42... may have the same or similar architecture. The acquisition unit 40 is for connection to an antenna 50 (other antennas and / or other PD sensors may also be connected to the unit 40), and includes a filtering stage 42 and a synchronization stage 44 that can synchronize the UHF signal from any of the antennas 50, 52, 54 with the synchronization signal 29 provided by the AC inverter 30; in other words, each acquisition unit time-synchronizes its signals internally.

[0044] The synchronization stage 44 may have several inputs for PD sensors, inputs for synchronization and power signals, and an output. Signals from the PD sensors are time-synchronized with the synchronization inputs. Outputs 45 (see FIGS. 4 and 5), 47 (FIG. 5) are for connection, for example, to an Ethernet network, or to an analog network or device, or to any other digital or analog device or network, for example, via copper wire, optical device, or fiber. Alternatively, the synchronization stage 40 may comprise means for wireless communication. The output of each of the acquisition units 40, 42... may be supplied to a computer or microprocessor 70 via any of these communication means.

[0045] The signal generated by the AC inverter is also provided as a power input signal to the acquisition unit 40. In other words, the same signal 29 output by the AC inverter 30 is supplied to each acquisition unit 40, 42, ... as both a power signal and a synchronization signal, thereby achieving system simplification and avoiding multiple connections.

[0046] The present invention has the ability to accommodate many configurations of SLD single line diagrams of HV substations and HV equipment locations.

[0047] In the device according to the invention, both stages 20 and 30, in particular the transformer 32, provide electrical insulation between the measuring device and the downstream side of the system, i.e. the acquisition units 40, 42 beyond the stages 20, 30, in particular if the measuring device comprises voltage transformers 10, 12, 14, which must be kept insulated from said downstream side, since they are particularly sensitive to short circuits that may occur, for example, on the line 37; the risk of destruction of the HV measuring devices associated with a complex cable connection network is eliminated, since the HV measuring devices are all connected to the switch device 20, and there is no need to connect each of the HV measuring devices to the different acquisition units 40, 42 by means of said connection network, which necessarily involves the risk of short circuits, which may be dangerous in particular for the voltage transformers 10, 12, 14; - Thanks to the phase compensation input 27, the time lag between the primary and secondary signals is negligible. the secondary signal (between the AC inverter 30 and the acquisition units 40, 42) can be transmitted over long distances thanks to the power supply; - the main output of the AC inverter 30 dedicated to synchronization benefits from additional power provided by the power source 33 of the device, both of which are combined within a module 44 of each acquisition unit 40; The main output voltage of the AC inverter is exactly in phase with the input signal.

[0048] The present invention is compatible with many different configurations of SLD single line diagrams of HV substations and HV equipment locations.

[0049] The time lag between the primary signal (input of switch 20) and the secondary signal (output of AC converter 30) is negligibly small.

[0050] After the default signals have been recorded by the device according to the invention, they can be compared with typical signatures recorded in a database. Once the type of signal has been recognized, it becomes possible to dismantle the primary equipment at a specific location in order to carry out the necessary maintenance work.

[0051] Although the AC reference switch device 20 and the AC inverter 30 have been described as two separate devices, they may alternatively be combined within the same device. [Explanation of symbols]

[0052] 2. High voltage equipment, circuit breakers 4. Circuit Breakers 5 Primary conductor 6. Circuit Breakers 10 Measuring devices, voltage transformers 10 i Voltage input, first input channel 12 Measuring devices, voltage transformers 12 i Voltage Input 14 Measuring devices, voltage transformers 14 i Voltage Input 20 Switch Devices, Switches, Stages 22 Signal detection and switching means 23 Power supply 24 outputs 25 Synchronous signal, input voltage and AC signal input 27 Phase signal, phase compensation input 29 AC power signal, output signal 30 AC inverters, AC converters, stages 32 Transformer 33 Power source, power source 34 Output 36 Microcontrollers 37 Wiring, lines 40 Acquisition Unit, Synchronization Stage 42 Acquisition unit, filtering stage 44 Synchronous Stages, Modules 45 Output 47 Output 50 UHF antenna 52 UHF antenna 54 UHF antenna 60 UHF antenna 62 UHF antenna 64 UHF antenna 70 Computer or Microprocessor 100 devices H1 transistor H2 transistor

Claims

1. - several synchronization signals (10) from at least one measuring device; ｉ , 12 ｉ , 14 ｉ 1. An AC reference switch device (20) comprising a plurality of inputs for inputting a synchronization signal, said switch device comprising means (22) for selecting an input from among said plurality of inputs based on the presence of a synchronization signal; an AC inverter (30) for providing a power and synchronization signal (29) based on at least the synchronization signal provided by the AC reference switch device (20); A device (100) for providing a synchronization signal (25) for identifying partial discharges in a GIS, comprising:

2. The device (100) of claim 1, wherein the AC inverter (30) comprises a transformer (32).

3. The device (100) of claim 1 or 2, wherein the AC inverter (30) comprises a microcontroller (36).

4. The device (100) of any one of claims 1 to 3, wherein the AC inverter (30) comprises a phase compensation means (36).

5. The AC reference switch device (20) is connected to a test signal input (10 ｉ 5. The device (100) of claim 1, comprising:

6. The device (100) of any one of claims 1 to 5, comprising a power supply (23) for the AC reference switch device (20).

7. 7. The device (100) of claim 1, further comprising a power supply (33) for the AC inverter (30), wherein the AC inverter (30) provides a power and synchronization signal based on the synchronization signal provided by the AC reference switch device (20) and the power supply (33).

8. - a device (100) for providing a synchronization signal according to any one of claims 1 to 7, a plurality of partial discharge acquisition units (40, 42), each one comprising a power input (41) and a synchronization input (43) both connected to the output of said AC inverter (30), and one or more signal inputs for receiving one or more signals from one or more partial discharge sensors; 1. A system for identifying partial discharge in a GIS, comprising:

9. The system (100) of claim 8, wherein one or more of the partial discharge acquisition units (40, 42) are connected to one or more partial discharge sensors (50-54, 60-64).

10. The system (100) of claim 9, wherein the one or more of the partial discharge sensors (50-54, 60-64) comprises one or more optical and / or acoustic and / or UHF sensors.

11. a metal tank (1) filled with gas and equipped with at least one primary conductor (5); - a plurality of sensors for detecting partial discharges; at least one measuring device (10, 12, 14) for detecting HV signals in said primary conductor (5); A system (100) according to claim 9 or 10, wherein each measuring device is connected to an input of the AC reference switching device (20) and each sensor is connected to an input of a partial discharge acquisition unit (40, 42). GIS equipped with.

12. the one or more sensors include one or more optical and / or acoustic and / or UHF sensors; and / or one or more measuring devices (10, 12, 14) include one or more voltage transformers (10, 12, 14); The GIS of claim 11.

13. - each of a plurality of measurement devices (10, 12, 14) providing a synchronization signal to one of the plurality of inputs of the AC reference switch device (20); - the AC inverter (30) provides a power and synchronization signal (29) to each of a plurality of partial discharge acquisition units (40, 42); - the partial discharge acquisition unit (40, 42) synchronizes the partial discharge signal with the synchronization signal (29) 13. The method for detecting partial discharges in a GIS according to claim 11 or 12,

14. The method of claim 13, wherein a test signal is provided to an input of the AC reference switch device (20).

15. 15. The method of claim 14, wherein the test signal is selected by the AC reference switch device (20) during a test phase of the GIS.

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