US 12,249,944 B2
In-situ inverter capacitance analyses and degradation alerts using variable operational modes of electric motor
Muhammad H. Alvi, Troy, MI (US); Khorshed Mohammed Alam, Canton, MI (US); Jiyu Zhang, Sterling Heights, MI (US); Chunhao J. Lee, Troy, MI (US); and Brian A. Welchko, Oakland Township, MI (US)
Assigned to GM Global Technology Operations LLC, Detroit, MI (US)
Filed by GM GLOBAL TECHNOLOGY OPERATIONS LLC, Detroit, MI (US)
Filed on Nov. 18, 2022, as Appl. No. 17/989,824.
Prior Publication US 2024/0171111 A1, May 23, 2024
Int. Cl. H02P 29/028 (2016.01); H02P 27/08 (2006.01)
CPC H02P 29/028 (2013.01) [H02P 27/08 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An apparatus, comprising:
a battery having first and second output terminals;
an inverter having terminals coupled respectively to the first and second output terminals, the inverter comprising a capacitor across the terminals and configured to power an electric motor;
a processor coupled to the inverter and configured to:
determine capacitance values of the capacitor during a plurality of precharge phases during which the electric motor is powered on;
determine whether a trend is present in the capacitance values, the trend indicating that a capacitance of the capacitor is rapidly changing relative to a threshold; and
generate an alert when the trend is present in the capacitance values.