公开(公告)号：US09989575B2

公开(公告)日：2018-06-05

申请号：US14837641

申请日：2015-08-27

Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC

Inventor： Xinyu Du ,  Shengbing Jiang ,  Atul Nagose ,  David B. Gumpert ,  Aaron B. Bloom ,  Rod Niner

IPC: G01R31/02 ,  H04L1/24 ,  G01R31/00

CPC classification number: G01R31/025 ,  G01R31/007 ,  H04L1/24

Abstract: A method is disclosed for detecting ground faults in a communications system. The method includes measuring a predetermined number of voltage points; determining if the measured voltage points represent recessive or dominant bits; identifying which of the predetermined number of voltage points represent inter-frame bits and which represent frame data bits based on whether the measured voltage points are recessive or dominant; calculating a maximum average voltage for the inter-frame bits; calculating an average frame voltage for all dominant bits within a frame; determining a high average dominant voltage count based on a number of frames for which the average frame voltage is greater than a high voltage threshold; and determining if a ground fault exists based on the average frame voltage and the high average dominant voltage count.