US 11,843,338 B2
Variable speed drive control
Mohamad Koteich, Vernon (FR); and Thomas Devos, Carrières-sous-Poissy (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 Jun. 10, 2022, as Appl. No. 17/837,309.
Claims priority of application No. 21305899 (EP), filed on Jun. 30, 2021.
Prior Publication US 2023/0006597 A1, Jan. 5, 2023
Int. Cl. H02P 27/08 (2006.01); H02P 23/12 (2006.01)
CPC H02P 27/085 (2013.01) [H02P 23/12 (2013.01); H02P 2201/03 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A method for controlling a variable speed drive driving an electric motor, the variable speed drive being connected to an electric power source, the variable speed drive comprising a passive DC-link and an inverter stage, the inverter stage being controlled by a first controller of the variable speed drive, the passive DC-link being connected to the inverter stage, the method comprising:
running, by the variable speed drive, the electric motor to reach a steady-state operating point;
measuring, by the variable speed drive, in response to reaching the steady state, a plurality of values of current or voltage of the passive DC-link;
computing, by a second controller, a frequency spectrum of the DC-link based on the plurality of values of current or voltage measured;
detecting, by the second controller, a specific resonance frequency by comparing amplitudes of the frequency spectrum to a predetermined pattern; and
modifying, by the first controller, filter parameters of a digital filter of the DC-link or control parameters of a control law of the electric motor based on the specific resonance frequency.