The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 03, 2001
Filed:
Jul. 29, 1999
Otis Elevator Company, Farmington, CT (US);
Abstract
Methods and apparatus are disclosed for calibrating a field-commutated motor (,) when under load, wherein initializing the motor (,) refers to relating data representative of the angle of the rotor in an uncalibrated coordinate system to a coordinate system having a known relationship to the excitation coils (,), typically mounted with the stator (,). The angular data can then be used for exciting the excitation coils (,) in the proper sequence and with the proper timing to obtain the desired speed, torque, direction or rotation, etc. of the motor (,). Test voltages having a known orientation are applied to one of the stator and the rotor, (whichever mounts the excitation coils (,)), and the angle of the rotor produced by the application of each of the test voltages noted. An equation is disclosed for determining an error angle between the uncalibrated and the known coordinate system as a function of the angles of the rotor produced by application of the test voltages. Apparatus for practicing the invention can include a processor (,), a power supply (,), and user input element (,) and a voltage and/or current sensor (,). The processor (,) can include appropriate means for executing the disclosed method steps.