US 12,216,165 B2
Method for categorizing performance of an electric traction machine being a permanent magnetic synchronous motor
Sebastian Hall, Hisings Backa (SE)
Assigned to VOLVO TRUCK CORPORATION, Gothenburg (SE)
Filed by VOLVO TRUCK CORPORATION, Gothenburg (SE)
Filed on Dec. 9, 2021, as Appl. No. 17/643,548.
Claims priority of application No. 20215480 (EP), filed on Dec. 18, 2020.
Prior Publication US 2022/0196740 A1, Jun. 23, 2022
Int. Cl. G01R 31/34 (2020.01); H02P 21/14 (2016.01); H02P 21/20 (2016.01)
CPC G01R 31/34 (2013.01) [H02P 21/141 (2013.01); H02P 21/20 (2016.02); H02P 2207/05 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A method for categorizing performance of an electric traction machine being a permanent magnetic synchronous motor, PMSM, the PMSM being coupled to a drive shaft, and powered by a battery via an inverter, the method comprising:
decoupling the PMSM from drive shaft;
performing a first retardation test to measure the flux linkage of the permanent magnets, PM flux, in the PMSM;
performing a second retardation test in which the inverter is disconnected, to measure the no-load power losses of the PMSM;
correlating the PM flux with the no-load power losses in a health parameter of the PMSM, and comparing the health parameter with reference data of known health parameters of a population of PMSMs;
categorizing the performance of the PMSM based on the compared health parameter.