US 12,449,487 B2
Detection of faults in redundant grounding systems
Robert A. De Stefano, Macomb Township, MI (US); and Jonathan O. Conell, Sterling Heights, MI (US)
Assigned to GM GLOBAL TECHNOLOGY OPERATIONS LLC, Detroit, MI (US)
Filed by GM Global Technology Operations LLC, Detroit, MI (US)
Filed on Jan. 13, 2023, as Appl. No. 18/154,390.
Prior Publication US 2024/0241190 A1, Jul. 18, 2024
Int. Cl. G01R 31/52 (2020.01); G01R 31/00 (2006.01)
CPC G01R 31/52 (2020.01) [G01R 31/007 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method of detecting ground loss of an electrical component, the method comprising:
monitoring a ground circuit including a first ground line connected to the electrical component and a second ground line connected to the electrical component, wherein the monitoring includes measuring a current through each of the first ground line and the second ground line, and measuring a voltage through each of the first ground line and the second ground line;
calculating a first resistance of the first ground line and a second resistance of the second ground line based on the measured current and the measured voltage;
estimating a difference between the first resistance and the second resistance, and comparing the estimated difference to a threshold difference, wherein the calculating and estimating the difference is performed at each of a plurality of time points;
based on the estimated difference being greater than the threshold difference, detecting a ground fault, diagnosing the ground fault based on a number of time points for which the ground fault is detected, and outputting an indication of the ground fault, wherein the ground fault is diagnosed as an intermittent fault based on the number of time points being greater than a first threshold number, and the ground fault is diagnosed as a permanent fault based on the number of time points being greater than a second threshold number, the second threshold number being greater than the first threshold number; and
based on detecting the ground fault, performing at least one of derating the electrical component and controlling a vehicle that includes the electrical component.