Method and apparatus for estimating a rotation speed of an electric motor
AssigneeABB AB
InventorSamuli HEIKKILÄ
Life of this patent
Estimating the term…
Abstract
A method is disclosed for estimating a rotation speed of an electric motor supplied by an inverter, by determining a time derivative of a stator current vector of the electric motor during a zero vector state of the inverter; and determining an estimate of the rotation speed of the electric motor on the basis of the determined time derivative of the stator current vector.
Claims24
A method for estimating a rotation speed of an electric motor supplied by an inverter, the method comprising:
- determining a time derivative of a stator current vector of the electric motor during a zero vector state of the inverter;
- and
- determining an estimate of the rotation speed of the electric motor on the basis of the determined time derivative of the stator current vector.
A computer program product comprising computer program code embodied on a computer readable medium, wherein the execution of the program code in a computer causes the computer to carry out the steps of:
- determining a time derivative of a stator current vector of the electric motor during a zero vector state of the inverter;
- and
- determining an estimate of the rotation speed of the electric motor on the basis of the determined time derivative of the stator current vector.
An apparatus for estimating a rotation speed of an electric motor supplied by an inverter, the apparatus comprising:
- means for determining a time derivative of a stator current vector of the electric motor during a zero vector state of the inverter;
- and
- means for determining an estimate of the rotation speed of the electric motor on the basis of the determined time derivative of the stator current vector.
An apparatus for estimating a rotation speed of an electric motor supplied by an inverter, the apparatus being configured to:
- determine a time derivative of a stator current vector of the electric motor during a zero vector state of the inverter;
- and
- determine an estimate of the rotation speed of the electric motor on the basis of the determined time derivative of the stator current vector.
Dependencies are inferred from the claim text.