US 11,722,084 B2
Backspinning motor control
Alain Dutrey, Fontaine sous Jouy (FR); Thomas Devos, Carrières sous Poissy (FR); and François Malrait, Jouy sur Eure (FR)
Assigned to Schneider Toshiba Inverter Europe SAS, Pacy sur Eure (FR)
Filed by Schneider Toshiba Inverter Europe SAS, Pacy sur Eure (FR)
Filed on Aug. 2, 2021, as Appl. No. 17/391,131.
Claims priority of application No. 20305905 (EP), filed on Aug. 6, 2020.
Prior Publication US 2022/0045639 A1, Feb. 10, 2022
Int. Cl. H02P 23/14 (2006.01); H02P 27/06 (2006.01)
CPC H02P 23/14 (2013.01) [H02P 27/06 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A method of control implemented in a variable speed drive for controlling an electric motor during backspin, wherein the method comprises:
determining, by the variable speed drive, a mechanical power value corresponding to power produced by the motor occurring at a backspin speed and an estimated load torque;
determining, by the variable speed drive, a specific electrical losses profile occurring at a motor flux level, wherein the specific electrical losses profile is an electrical losses profile for which electrical losses coincide with the mechanical power value such that little or no excess power is produced by the motor;
determining, by the variable speed drive, a flux reference and a speed reference to be applied to the motor in order for the mechanical power value to coincide with the specific electrical losses profile such that little or no excess power is produced by the motor; and
controlling, by the variable speed drive, the backspin speed of the motor to maintain the coincidence of the mechanical power value with the specific electrical losses profile such that little or no excess power is produced by the motor.