US 12,259,422 B2
Method and system for insulation monitoring in the aircraft power district and its loads
Ali Khalid Al-Karaghouli, West Midlands (GB); and Grzegorz Popek, Birmingham (GB)
Assigned to HAMILTON SUNDSTRAND CORPORATION, Charlotte, NC (US)
Filed by Hamilton Sundstrand Corporation, Charlotte, NC (US)
Filed on Jan. 5, 2023, as Appl. No. 18/150,462.
Claims priority of application No. 22275001 (EP), filed on Jan. 5, 2022.
Prior Publication US 2023/0213571 A1, Jul. 6, 2023
Int. Cl. G01R 31/12 (2020.01); G01R 31/00 (2006.01)
CPC G01R 31/1272 (2013.01) [G01R 31/008 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A method for monitoring insulation in a power system comprising a motor drive circuit configured to convert DC power from a power source to AC power to drive a motor, the method comprising:
boosting a DC link voltage of an inverter of the motor drive;
isolating the motor drive circuit from the power source;
performing at least one isolation test by providing a current path through components of the motor drive and preferably a motor connected to the output of the inverter to be tested;
monitoring the current during each isolation test to detect partial discharge or excessive leakage from the current path, thereby indicating that there exists defects in the insulation in the current path.