Measurement of partial discharges of electrically operated device

Abstract

The invention relates to an electrical operating device (1) comprising:-a high-voltage region (12) comprising: o a cable connection chamber (121) for a wire feed-through (122) and o a capacitive coupling electrode or inductive coupler designed to couple out a first frequency range, the capacitive coupling electrode or inductive coupler being connected to the wire feed-through (122); a low-voltage region (11) comprising: o a system (111) for measuring the high-frequency current, designed to couple out a second frequency range and to detect the voltage in the second frequency range; and a voltage display system (112) configured to measure a third frequency range and to detect a voltage within the third frequency range. The disclosed device produces the advantage of measuring partial discharge by voltage detection in a second frequency range by means of a system (111) for measuring high-frequency current. The invention also relates to an associated method.

Description

[0001] Regardless of the grammatical gender of a particular term, it includes terms that are male or female. Technical Field

[0002] This invention relates to an electrical operating device. Furthermore, the invention also relates to an associated method for measuring partial discharge at the wire feeder of an electrical operating device. Background Technology

[0003] Partial discharge measurement (TE measurement) is a standard method for assessing the condition of electrical operating devices. TE measurement has also proven effective in high-voltage and medium-voltage switchgear. A variety of methods are used, including ultra-high frequency (UHF) sensors, TEV sensors, and measurement methods in the high-frequency (HF) range, such as coupling capacitors, HFCTs (High Frequency Current Transformers), or other measuring coils. Frequent or continuous measurement is desired.

[0004] This requires modifications to the electrical operating system to install the corresponding sensor system. This incurs costs that may reduce or offset the economic viability of "TE measurement" applications, whether in new facilities or existing electrical operating systems.

[0005] Currently, this problem is addressed by installing the HFCT in the high-voltage compartment of the switchgear, specifically by placing the HFCT around the cable shielding of the switchgear's connecting conductors. However, this solution is complex to install and maintain.

[0006] The objective of this invention is to provide an improved solution for partial discharge measurement. Summary of the Invention

[0007] This invention is based on the features of the independent claims. Advantageous extensions and designs are the subject of the dependent claims. The designs, applications, and advantages of this invention will become apparent from the following description and drawings.

[0008] Regardless of the grammatical gender of a particular term, it includes terms that are male or female.

[0009] This invention relates to an electrical operating device, comprising: - High-voltage areas, including: o Cable connection chamber for wire feeder devices, and The capacitive coupling electrode or inductive coupler is configured to couple the first frequency range of the output. The capacitive coupling electrode or inductive coupler is connected to the wire feedthrough device. -Low-pressure areas, including: Systems used for measuring high-frequency currents (especially high-frequency converters (HFCTs), shunt resistors, and magnetic field sensors based on GMR or Hall effect) are configured to couple an output to a second frequency range and perform voltage detection within that second frequency range. The voltage display system (especially the "voltage indicator system" (VIS)) is configured to measure and detect voltage within a third frequency range, and... - A wire feeder device, including a first connecting end and a second connecting end. The first connection end is located in the cable connection chamber. The second connection terminal is located in the low-voltage area, and The wire feeder extends from the cable connection chamber to the system for measuring high-frequency current and the voltage display system.

[0010] The disclosed device has the following advantages: partial discharge is measured by voltage detection in the second frequency range using a system (high-frequency converter) for measuring high-frequency current.

[0011] High voltage exists in high-voltage areas. In the context of this invention, "high voltage" should be understood as an AC voltage greater than or equal to 1 kV (International unit: kilovolt) and / or a DC voltage greater than or equal to 1.5 kV (International unit: kilovolt).

[0012] Low voltage exists in low-voltage regions. “Low voltage” should be understood as AC voltage up to 1000 volts (SI) and / or DC voltage up to 1500 volts (SI).

[0013] The components in the low-voltage area are electrically connected, while the remaining components of the electrical operating device (especially in the high-voltage area) are electrically isolated from the low-voltage area.

[0014] Inductive couplers are particularly configured as Rogowski coils.

[0015] Systems used for measuring high-frequency currents are particularly configured as high-frequency converters (HFCTs), shunt resistors, and magnetic field sensors based on GMR or the Hall effect.

[0016] Voltage display systems are specifically configured as “voltage indicator systems” (VIS).

[0017] The wire feeder device can also be referred to as a connecting conductor. In one embodiment, the connecting conductor has a cable shielding layer. Alternatively, an unshielded cable can also be used as the connecting conductor.

[0018] In other words, the core idea of ​​the present invention is to couple a second frequency range (particularly 100kHz to 100MHz) from the signal path of the system for detecting voltage through a system for measuring high-frequency current (particularly HFCT (high-frequency converter)).

[0019] Many electrical operating devices (such as high-voltage and medium-voltage switchgear) already have capacitive coupling electrodes (built into bushings) installed for voltage sensing according to IEC 62271-213 and similar standards (i.e., for transmitting voltage signals such as 50Hz and 100MHz), or for general field control. However, until now, only 50Hz signals have been used for voltage sensing (partially via VIS). However, a wider frequency range can be coupled via capacitive coupling electrodes, including frequencies of interest for partial discharge measurements in the high-frequency (HF) range (100kHz to 100MHz). The solution proposed in this invention can serve as an alternative to the current solution.

[0020] The HFCT placed according to the present invention physically measures only small measurement signals because, empirically, the coupling capacitance of the feedthrough (which is relatively small because the complex resistance is relatively high) is in the pF (picofarad) range. However, interference / noise is even smaller, so small measurement signals have no effect.

[0021] This invention also offers the following advantages: due to the thin signal wires, the installation space required for the HFCT sensor can be very small, which allows for optimized design. Furthermore, the resulting sensor system is also smaller because the cable introduced into the low-voltage area has only a small diameter.

[0022] This invention also has the following advantages: by completing assembly in the factory, the system can be calibrated in a defined environment. The HFCT can be assembled at the factory (at the manufacturer's site, not at the customer's site). The proposed solution thus offers the following advantages: • Complete the assembly, testing, and calibration of the new facility within the factory. • Simplified assembly and wiring feedthrough, as the signal (taken off by the HFCT in the low-voltage area of ​​the switch facility) is close to the evaluation system VIS (in the low-voltage area). • Simplifies the assembly of facilities already in operation, as they only need to operate within a low-voltage area. Therefore, shutdown is unnecessary when performing interference light tests on switchgear according to IEC 62271-200.

[0023] The present invention also has the following advantages: a 50Hz signal can be coupled out onto the VDIS (=VIS) (e.g., for creating a PRPD mode), especially when the VDIS according to IEC 62271-213 has an optional voltage output terminal according to that standard. Because the voltage level of this signal is low, simple further processing is possible.

[0024] In an extension of the invention, a potential isolation tap is provided between the high-voltage region and the low-voltage region.

[0025] This potential isolation tap prevents high voltage from appearing in low voltage areas within high voltage regions. The potential isolation tap is specifically configured as a capacitor tap.

[0026] Here, particularly in the high-voltage region, the capacitor tap acts as the first capacitor, while in either the high-voltage or low-voltage region, there exists a second impedance much smaller than the first capacitor. Through the resulting voltage divider, in both cases, only a low voltage exists when current enters the low-voltage region.

[0027] High-pressure and low-pressure areas are technically distinct regions. Therefore, low-pressure guidelines can be followed in low-pressure areas, while high-pressure guidelines can be followed in high-pressure areas.

[0028] In a further extension of the invention, the system for measuring high-frequency current is arranged in a low-voltage region. This is advantageous because it operates according to low-voltage guidelines within the low-voltage region.

[0029] In a further extension of the present invention, the electrical operating device is configured as follows: - Critical electrical operating equipment and / or - Electrical switchgear and / or -High-voltage facilities and / or - Transformers and / or -engine.

[0030] Critical electrical operating equipment should be understood as electrical operating equipment that has a critical function in itself and / or its components. Critical function refers to the damage that, in the event of failure, would result in damage far exceeding the average level (particularly through secondary damage).

[0031] High-voltage facilities have high voltage. High voltage exists within high-voltage areas. In the context of this invention, high voltage should be understood as an AC voltage greater than or equal to 1 kV (instantaneous unit: kilovolt) and / or a DC voltage greater than or equal to 1.5 kV (instantaneous unit: kilovolt).

[0032] In a further extension of the present invention: - Within the first frequency range, frequencies are from 16.66 Hz to 100 MHz, particularly from 50 Hz to 100 Hz, and / or - In the third frequency range, frequencies are from 16.66 Hz to 400 Hz, particularly from 50 Hz to 60 Hz, and / or - In the second frequency range, the frequency is from 100KHz to 100MHz.

[0033] Here, systems used for measuring high-frequency currents, particularly HFCTs, are preferably designed to be uncoupled from low-frequency interference (especially <100kHz) or extremely high-frequency interference (especially >100MHz) to obtain a favorable signal-to-noise ratio. This is advantageous because frequencies from 100kHz to 100MHz are particularly important for partial discharge measurements.

[0034] In the third frequency range, the 16.66 Hz frequency is particularly relevant to applications in railway travel, and the 400 Hz frequency is particularly relevant to applications in aviation travel, especially aircraft.

[0035] In a further extension of the invention, the wire feeder extends from the cable connection chamber through a system for measuring high-frequency current to a voltage display system.

[0036] Therefore, the wire feedthrough device first reaches the system used to measure high-frequency current, and then extends from that system to the voltage display system.

[0037] In a further extension of the invention, the wire feedthrough device extends from the capacitive coupling electrode to a system for measuring high-frequency current.

[0038] Therefore, the wire feedthrough first reaches the capacitive coupling electrode or inductive coupler, and then continues from there to the system used for measuring high-frequency current. In particular, the wire feedthrough then continues to the voltage display system.

[0039] In a further extension of the invention, the high-pressure region and the low-pressure region are separated from each other. "Separated" means that there is no overlapping area. It also means that there is a boundary.

[0040] In a further extension of the invention, current isolation is provided between the high-voltage region and the low-voltage region. In particular, the boundary between the high-voltage region and the low-voltage region is thereby constituted as the current isolation.

[0041] In a further extension of the invention, the cable feedthrough is grounded via a first inductor in the low-voltage region. This optimizes the cable feedthrough to IVDS (=VIS): according to this embodiment, the cable shield is preferably grounded via a first inductor near the system used for measuring high-frequency current, see also [reference needed]. Figure 2 .

[0042] In a further extension of the invention, the cable feedthrough device passes through the system used for measuring high-frequency current together with the grounding connection. This optimizes the cable feedthrough to IVDS (=VIS): according to this embodiment, the cable shield and the grounding connection of IVDS (=VIS) pass through the HFCT together, for which see also... Figure 3 .

[0043] In a further extension of the invention, the wire feedthrough device is designed to have an electrical absorption circuit between the system for measuring high-frequency current and the cable connection chamber. This constructs an absorption circuit specifically tuned to a frequency favorable for partial discharge (TE) measurement. Here, the development results show that this absorption circuit is automatically generated by the system for measuring high-frequency current (partially a high-frequency converter (HFCT)). This system for measuring high-frequency current is advantageously designed to enable measurement of favorable frequencies within a second frequency range of 100 kHz to 100 MHz.

[0044] In a further extension of the invention, the electrical operating device according to the invention further includes: - A second inductor, wherein the second inductor is designed such that the second frequency range corresponds to the convolution of the signal from the partial discharge point to the capacitively coupled electrode.

[0045] In particular, systems used for measuring high-frequency current, especially high-frequency converters (HFCTs), are themselves configured as a second inductor. Alternatively, systems used for measuring high-frequency current may have an additional component as a second inductor.

[0046] The second inductor and the resulting absorption circuit are configured to preferentially measure a second frequency range that convolve the partial discharge signal (PD signal) from the partial discharge point (partial discharge point, particularly the defect point) with the transfer function from the defect point to the capacitively coupled electrode. Empirically, these are specific frequencies in the range of 100 kHz to 100 MHz for variables of electrical operating devices (particularly switchgear and its "critical electrical operating devices" and insulated feedthroughs). Therefore, the second inductor is tuned to the second frequency range.

[0047] The present invention also includes a method for measuring partial discharge at the wire feedthrough of an electrical operating device, comprising the following steps: - Provides a wire feeder device having a first connection end and a second connection end. - The first connection terminal is arranged in the cable connection room in the high-voltage area. - A second connection terminal is arranged on the voltage display system in the low-voltage area, so that the wire feeder extends from the cable connection chamber to the system for measuring high-frequency current and the voltage display system. - The first frequency range is coupled out via a capacitive coupling electrode or an inductive coupler, wherein the capacitive coupling electrode or inductive coupler is located in a high-voltage region. -Measure the third frequency range using the voltage display system. - Voltage detection is performed within the third frequency range via a voltage display system. - A second frequency range is output via system coupling for measuring high-frequency current, and Partial discharge is measured by voltage detection in a second frequency range using a system for measuring high-frequency current.

[0048] The present invention also includes a method for measuring partial discharge using an electrical operating device according to the present invention. Attached Figure Description

[0049] The features and advantages of the present invention will become apparent from the following illustrated explanations of several embodiments.

[0050] Figure 1 A schematic diagram of the electrical operating device according to the present invention is shown. Figure 2 A circuit diagram of a first embodiment of the electrical operating device according to the present invention is shown, and Figure 3 A circuit diagram of a second embodiment of the electrical operating device according to the present invention is shown. Detailed Implementation

[0051] Figure 1 A schematic diagram of an electrical operating device 1 according to the present invention is shown, comprising: -High-voltage area 12 includes: o Cable connection chamber 121 for wire feeder device 122, and The capacitive coupling electrode or inductive coupler is configured to couple the output frequency range, wherein the capacitive coupling electrode or inductive coupler is connected to the wire feedthrough device 122. -Low-pressure area 11 includes: The system 111 for measuring high-frequency current is configured to couple an output to a second frequency range and perform voltage detection within that second frequency range. The voltage display system 112 is configured to measure a third frequency range and perform voltage detection within that third frequency range. - The wire feeder device 122 includes a first connecting end and a second connecting end. The first connection end is located in the cable connection chamber 121. The second connection end is located in the low-pressure area 11, and The wire feeder device 122 extends from the cable connection chamber 121 to the system 111 for measuring high-frequency current and the voltage display system 112.

[0052] Figure 2 A circuit diagram of a first embodiment of the electrical operating device 1 according to the present invention is shown. In this extension of the invention, the cable feedthrough 122 is grounded through a first inductor 113 in the low-voltage region 12. Thus, the cable feedthrough 122 to IVDS 112 (=VIS 112) is optimized: according to this embodiment, the cable shield is grounded through a first inductor 113 near the system 111 for measuring high-frequency current. Furthermore, a circuit diagram already shown... Figure 1 The components described in [the document / document].

[0053] Figure 3 A circuit diagram of a second embodiment of the electrical operating device 1 according to the present invention is shown. In this extension of the invention, the cable feedthrough 122 passes through the system 111 for measuring high-frequency current together with the grounding connection 114. This optimizes the cable feedthrough 122 to IVDS 112 (=VIS 112): according to this embodiment, the cable shield and the grounding connection 114 of IVDS 112 (=VIS 112) pass through HFCT 111 together. Furthermore, a circuit diagram already shown... Figure 1 The components described in [the document / document].

[0054] Although the invention has been illustrated and described in detail by way of embodiments, the invention is not limited to the disclosed examples, and those skilled in the art can derive other variations therefrom without departing from the scope of the invention.

Claims

1. An electrical operating device (1), comprising: - High-voltage area (12), including: o Cable connection chamber (121) for wire feeder device (122); and o Capacitive coupling electrode or inductive coupler configured to couple output a first frequency range, wherein the capacitive coupling electrode or the inductive coupler is connected to the wire feedthrough device (122). -Low-pressure area (11), including: The system (111) for measuring high-frequency current is configured to couple an output to a second frequency range and perform voltage detection within that second frequency range. The voltage display system (112) is configured to measure a third frequency range and perform voltage detection within the third frequency range, and -The cable feeder device (122) includes a first connecting end and a second connecting end. The first connection end is arranged in the cable connection chamber (121). The second connection end is arranged in the low-pressure area (11), and The wire feeder device (122) extends from the cable connection chamber (121) to the system for measuring high-frequency current (111) and the voltage display system (112).

2. The electrical operating device (1) according to claim 1, wherein, A potential isolation tap is provided between the high-voltage region (12) and the low-voltage region (11).

3. The electrical operating device (1) according to any one of the preceding claims, wherein, The system (111) for measuring high-frequency current is arranged in the low-voltage region (11).

4. The electrical operating device (1) according to any one of the preceding claims is configured as follows: - Critical electrical operating devices (1) and / or - Electrical switchgear (1) and / or - High-voltage facilities (1) and / or - Transformer (1) and / or - Engine (1).

5. The electrical operating device (1) according to any one of the preceding claims, wherein: - In the first frequency range, the frequency is 16.66 Hz to 100 MHz, particularly 50 Hz to 100 Hz, and / or - In the third frequency range, the frequency is from 16.66 Hz to 400 Hz, particularly from 50 Hz to 60 Hz, and / or - In the second frequency range, the frequency is from 100KHz to 100MHz.

6. The electrical operating device (1) according to any one of the preceding claims, wherein, The wire feeder (122) extends from the cable connection chamber (121) via the system (111) for measuring high-frequency current to the voltage display system (112).

7. The electrical operating device (1) according to any one of the preceding claims, wherein, The wire feedthrough device (122) extends from the capacitive coupling electrode to the system (111) for measuring high-frequency current.

8. The electrical operating device (1) according to any one of the preceding claims, wherein, The high-pressure region (12) and the low-pressure region (11) are separated from each other.

9. The electrical operating device (1) according to any one of the preceding claims, wherein, There is current isolation between the high-voltage region (12) and the low-voltage region (11).

10. The electrical operating device (1) according to any one of the preceding claims, wherein, The wire feeder (122) is grounded through a first inductor (113) in the low-voltage region (11).

11. The electrical operating device (1) according to any one of the preceding claims, wherein, The wire feeder (122) passes through the system (111) for measuring high-frequency current together with the grounding connection (114).

12. The electrical operating device (1) according to any one of the preceding claims, wherein, The wire feeder device (122) is designed such that there is an electrical absorption circuit between the system (111) for measuring high-frequency current and the cable connection chamber (121).

13. The electrical operating device (1) according to any one of the preceding claims further includes: - A second inductor, wherein the second inductor is designed such that the second frequency range corresponds to the convolution of the signal of the transfer function from the partial discharge point to the capacitively coupled electrode.

14. A method for measuring partial discharge at a wire feeder (122) of an electrical operating device (1), comprising the following steps: - Provide a wire feeder device (122) having a first connection end and a second connection end. - The first connection end is arranged in the cable connection chamber (121) of the high-voltage area (12), - The second connection terminal is arranged on the voltage display system (112) in the low-voltage area (11) such that the wire feeder (122) extends from the cable connection chamber (121) to the system (111) for measuring high-frequency current and the voltage display system (112). - A first frequency range is coupled out via a capacitive coupling electrode or an inductive coupler, wherein the capacitive coupling electrode or the inductive coupler is located within the high-voltage region (12). -Measure the third frequency range using the voltage display system (112), - Voltage detection is performed within the third frequency range via the voltage display system (112). - The second frequency range is coupled out through the system (111) for measuring high-frequency current, and Partial discharge is measured by voltage detection in the second frequency range using the system (111) for measuring high-frequency current.

15. The method according to claim 14, utilizing the electrical operating device (1) according to any one of claims 1 to 13.

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