US 11,867,718 B2
Method and device for identifying and locating cyclic momentary insulation faults in an underground power supply system
Dieter Hackl, Fernwald (DE); Karl Schepp, Reiskirchen (DE); and Pascal Becker, Gruenberg (DE)
Assigned to Bender GmbH + Co. KG, Gruenberg (DE)
Filed by Bender GmbH & Co. KG, Gruenberg (DE)
Filed on Oct. 25, 2022, as Appl. No. 17/972,644.
Claims priority of application No. 10 2021 127 848.1 (DE), filed on Oct. 26, 2021.
Prior Publication US 2023/0125797 A1, Apr. 27, 2023
Int. Cl. G01R 31/52 (2020.01); G01R 31/08 (2020.01); G01R 31/58 (2020.01); G01R 31/28 (2006.01)
CPC G01R 31/083 (2013.01) [G01R 31/2839 (2013.01); G01R 31/52 (2020.01); G01R 31/58 (2020.01)] 15 Claims
OG exemplary drawing
 
1. A method for identifying and locating cyclic momentary insulation faults in an ungrounded power supply system having a consumer connected via a branch circuit, the method comprising the steps:
detecting a fault current caused by the momentary insulation fault as a differential current in the branch circuit being monitored and displaying the temporal progression of the differential current via a differential current signal by means of a differential current sensor,
providing a processing signal which temporally describes a process sequence of a process taking place in the consumer,
correlating the differential current signal with the processing signal in a computing unit in order to yield a correlation signal as a measure for a temporal match between the differential current signal and the processing signal, and
signaling the momentary insulation fault via the computing unit by means of a signaling signal if the correlation signal shows the temporal match.