# US 12,007,427 B2 · Electrical circuit > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,007,427 B2 - Document ID: US12007427B2 - Status: Granted - Kind: B2 - Application number: 17/916,105 - Filed: 2021-03-29 - Published: 2023-06-29 - Granted: 2024-06-11 - Earliest claimed: 2020-03-31 - Assignees: BAUR GmbH - Applicants: Baur GmbH - Inventors: Stefan Heinzle; Mathias Hupp; Manfred Bawart; Martin Jenny - Web page: https://patentgrep.com/patent/US12007427B2 ## CPC - G01R 31/1272: {of cable, line or wire insulation, e.g. using partial discharge measurements (locating faults in cables G01R31/083)} - G01R 31/086: {in power transmission or distribution networks, i.e. with interconnected conductors} - G01R 31/14: Circuits therefor {, e.g. for generating test voltages, sensing circuits (G01R31/1209 - G01R31/1227 take precedence; for testing switches G01R31/327)} - Y04S 10/52: Outage or fault management, e.g. fault detection or location - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - Y04S: SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS ## Abstract An electrical circuit for connecting an electrical measurement device (16), which is used to measure partial discharges in a power grid having an operating voltage in the range of 1-69 kV, and which has an A/D converter (17) for converting a measured voltage pulse into a digital signal and has a microprocessor unit (18) for evaluating the digital signal, with a measurement output of a capacitive voltage testing system (3) of switchgear for the power grid having the operating voltage in the range of 1-69 kV. The electrical circuit (8) has a frequency response matching resistor (9) which is connected between an input line (10) for connection to the live pole of the measurement output and to ground, and has a high-pass filter (11) connected down-circuit of the frequency response matching resistor (9). ## Claims ### Claim 1 An electrical circuit for connecting an electrical measurement device, which is configured for measurement of partial discharges in a power grid having an operating voltage in a range of 1 kV to 69 kV, and which includes an A/D converter for converting a measured voltage pulse into a digital signal, and a microprocessor for evaluating the digital signal, with a measurement output of a capacitive voltage testing system of switchgear for the power grid which has an operating voltage in the range of 1 kV to 69 kV, the electrical circuit comprising: a frequency response matching resistor, which is connected between an input line configured for connection to a live pole of the measurement output and ground, and a high-pass filter connected down-circuit of the frequency response matching resistor. ### Claim 2 (depends on 1) The electrical circuit as claimed in claim 1, the measurement output of the capacitive voltage testing system is configured as a terminal socket. ### Claim 3 (depends on 1) The electrical circuit as claimed in claim 1, wherein a rating of the frequency response matching resistor is greater than 25 kΩ. ### Claim 4 (depends on 3) The electrical circuit as claimed in claim 3, the rating of the frequency response matching resistor is in a range of 50 kΩ to 200 kΩ. ### Claim 5 (depends on 1) The electrical circuit as claimed in claim 1, wherein a cut-off frequency of the high-pass filter is in a range of 50 kHz to 200 kHz. ### Claim 6 (depends on 1) The electrical circuit as claimed in claim 1, further comprising a low-pass filter connected down-circuit of the frequency response matching resistor. ### Claim 7 (depends on 6) The electrical circuit as claimed in claim 6, further comprising an amplifier connected down-circuit of the high-pass filter and the low-pass filter. ### Claim 8 (depends on 7) The electrical circuit as claimed in claim 7, further comprising an impedance matching resistor arranged down-circuit of the amplifier, configured for impedance matching to the input resistor of the measurement device. ### Claim 9 (depends on 1) A measuring assembly for the measurement of partial discharges at a measurement output of a capacitive voltage testing system of switchgear for a power grid having an operating voltage in the range of 1 kV to 69 kV, the measuring assembly comprising: an A/D converter configured to convert a measured voltage pulse into a digital signal, a microprocessor configured to evaluate the digital signal, and the electrical circuit as claimed in claim 1 arranged up-circuit of the A/D converter. ### Claim 10 (depends on 9) The measuring assembly as claimed in claim 9, wherein the measurement output of the capacitive voltage testing system is configured as a terminal socket. ### Claim 11 (depends on 9) The measuring assembly as claimed in claim 9, wherein for the measurement of partial discharges between two conductors in a multi-pole cable for voltages in the range of 1 kV to 69 kV, the microprocessor is configured to mutually subtract measurement signals obtained from partial discharge measurements on the two conductors. ### Claim 12 (depends on 9) The measuring assembly as claimed in claim 9, further comprising a time detection unit for detection of a time differential between voltage pulses which are detected by the measuring assembly for the identification of a location of a partial discharge. ### Claim 13 (depends on 9) A measuring system for the identification of the location of a partial discharge in a power grid having an operating voltage in the range of 1 kV to 69 kV, the measuring system comprising at least two of the measuring assemblies as claimed in claim 9 for the measurement of partial discharges on a respective measurement output of a capacitive voltage testing system arranged at a respective end of a cable in the power grid, and the measuring assemblies further comprise mutually synchronizable time detection units configured to detect a difference in propagation times of a voltage pulse generated by a partial discharge to the respective measuring assembly. ### Claim 14 (depends on 13) The measuring system as claimed in claim 13, further comprising at least one evaluation unit configured to evaluate a difference detected in the propagation times of a voltage pulse generated by a partial discharge, in order to determine a location of the partial discharge. ### Claim 15 (depends on 12) The measuring system as claimed in claim 12, wherein the measuring assemblies further comprise communication units for mutual exchange of data. ### Claim 16 (depends on 3) The electrical circuit as claimed in claim 3, wherein the rating of the frequency response matching resistor is lower than 400 kΩ. ### Claim 17 (depends on 6) The electrical circuit as claimed in claim 6, wherein the low-pass circuit has a cut-off frequency in a range of 5 MHz to 20 MHz. ### Claim 18 (depends on 8) The electrical circuit as claimed in claim 8, wherein the impedance matching resistor has a rating of less than 100Ω. ### Claim 19 (depends on 15) The measuring system as claimed in claim 15, wherein the mutual exchange of data is wireless.