US 12,187,576 B2
Drive system and method for controlling a drive system
Mikko Paakkinen, Helsinki (FI); Tuukka Kauppinen, Helsinki (FI); and Lauri Stolt, Helsinki (FI)
Assigned to KONE CORPORATION, Helsinki (FI)
Filed by KONE Corporation, Helsinki (FI)
Filed on Jun. 2, 2022, as Appl. No. 17/830,564.
Application 17/830,564 is a continuation of application No. PCT/EP2019/083777, filed on Dec. 5, 2019.
Prior Publication US 2022/0289521 A1, Sep. 15, 2022
Int. Cl. B66B 1/30 (2006.01); B66B 25/00 (2006.01)
CPC B66B 1/30 (2013.01) [B66B 25/003 (2013.01); B66B 2201/212 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A drive system for driving an electric motor, the drive system comprising a drive control unit and a frequency converter comprising a speed controller, wherein the drive control unit is configured to:
define a speed reference of the electric motor, wherein the speed reference represents the speed of the electric motor as a function of time;
preset operating parameters of the speed controller of the frequency converter to provide a first response time of the speed controller, before a drive of the electric motor is initiated according to the speed reference;
adjust at least one operating parameter of the speed controller of the frequency converter to provide a second response time of the speed controller, after the speed of the electric motor reaches a constant speed according to the speed reference, wherein the second response time of the speed controller is slower than the first response time of the speed controller; and
readjust the at least one operating parameter of the speed controller of the frequency converter to provide the first response time of the speed controller, before a deceleration from the constant speed is initiated according to the speed reference,
wherein the drive control unit is configured to apply a time delay after the constant speed is achieved and before adjusting the at least one operating parameter of the speed controller of the frequency converter to provide the second response time of the speed controller, and to readjust the at least one operating parameter of the speed controller of the frequency converter to provide the first response time of the speed controller with a time advance applied before the deceleration from the constant speed is initiated, such that during a period where the speed of the electric motor maintains the constant speed according to the speed reference, the speed controller of the frequency converter sequentially achieves the first response time, then the second response time and then the first response time.