公开(公告)号：US11271507B2

公开(公告)日：2022-03-08

申请号：US17106733

申请日：2020-11-30

Applicant: ABB Schweiz AG

Inventor： Toni Kuikka ,  Juho Salminen ,  Petri Havanto

IPC: H02P23/14 ,  G01R31/34 ,  H02P3/06

Abstract: According to an aspect, there is provided a method for evaluating safety of a speed of a motor controlled by a frequency converter. The method includes, first, measuring first, second and third phase currents of three-phase electric power fed from the frequency converter to the motor and forming first, second and third current measurement pairs based thereon. Then, the speed of the motor is estimated separately based on each measurement pair to produce respective first, second and third estimates for the speed of the motor. A voting logic is applied to the first, second and third estimates for the speed of the motor. A voting logic is applied to the first, second and third estimates. An output of the voting logic is fed to a safety logic controlling at least one safety function of the frequency converter. The output of the voting logic includes an estimate for the speed of the motor and an indication whether or not said final estimate is valid according to the voting logic.

公开(公告)号：US20210167710A1

公开(公告)日：2021-06-03

申请号：US17106733

申请日：2020-11-30

Applicant: ABB Schweiz AG

Inventor： Toni Kuikka ,  Juho Salminen ,  Petri Havanto

IPC: H02P23/14 ,  H02P3/06 ,  G01R31/34

Abstract: According to an aspect, there is provided a method for evaluating safety of a speed of a motor controlled by a frequency converter. The method comprises, first, measuring first, second and third phase currents of three-phase electric power fed from the frequency converter to the motor and forming first, second and third current measurement pairs based thereon. Then, the speed of the motor is estimated separately based on each measurement pair to produce respective first, second and third estimates for the speed of the motor. A voting logic is applied to the first, second and third estimates. An output of the voting logic is fed to a safety logic controlling at least one safety function of the frequency converter. The output of the voting logic comprises an estimate for the speed of the motor and an indication whether or not said final estimate is valid according to the voting logic.