Method and system estimating rotor angle of an electric machine
AssigneeDeere & Company
InventorLav Thyagarajan
Life of this patent
Estimating the term…
Abstract
Position samples are stored from an encoder coupled to a permanent magnet electric machine. A data processor determines first changes in position between successive position samples and second changes between successive first changes in position. A data processor determines whether each first change in position is generally increasing, decreasing or constant. A corrective motion factor is applied to each stored position sample based on whether the first change in position is generally increasing or decreasing. The data processor estimates a final rotor angle of the electric machine based on a particular one of the position samples and a corresponding first change in position associated with the particular one of the position samples corresponding to a respective time.
Claims18
A method for estimating rotor angle of an electric machine, the method comprising:
- receiving position samples from an encoder coupled to a permanent magnet electric machine;
- storing the position samples in a data storage device;
- determining a first plurality of first changes in position between successive position samples;
- determining a second plurality of second changes between successive first changes in position;
- determining whether each first change in position is generally increasing, decreasing or constant;
- applying a corrective motion factor to each stored position sample based on whether the first change in position is generally increasing or decreasing;
- and
- estimating a final rotor angle of the electric machine based on a particular one of the position samples and a corresponding first change in position associated with the particular one of the position samples corresponding to a respective time.
A system for estimating rotor angle of an electric machine, the system comprising:
- an encoder coupled to a permanent magnet electric machine;
- a primary processing module for receiving position samples from the encoder and storing the position samples in a data storage device;
- a data processor of the primary processing module determining a first plurality of first changes in position between successive position samples, determining a second plurality of second changes between successive first changes in position, and determining whether each first change in position is generally increasing, decreasing or constant;
- the data processor applying a corrective motion factor to each stored position sample based on whether the first change in position is generally increasing or decreasing;
- and
- the data processor estimating a final rotor angle of the electric machine based on a particular one of the position samples and a corresponding first change in position associated with the particular one of the position samples corresponding to a respective time.
Dependencies are inferred from the claim text.