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:
Dec. 26, 2000
Filed:
Jun. 11, 1999
Kathryn Lynn Pattok, Wiesbaden, DE;
Steven James Collier-Hallman, Frankenmuth, MI (US);
Ashok Chandy, Fenton, MI (US);
Julie Ann Kleinau, Bay City, MI (US);
Delphi Technologies, Inc., Troy, MI (US);
Abstract
An electric motor actuator used in an environment of varying loads for varying time periods is efficiently designed to a predetermined specification in terms of both motor load and time and operated up to but not exceeding this specification over the full expected operating range. A motor load signal is low pass filtered with a plurality of time constants spanning a range of expected motor operation to generate a plurality of filtered motor load signals each associated with one of the time constants. Each of these filtered motor load signals is compared with a predetermined reference value corresponding to the associated time constant. If one or more of the filtered motor load signals exceeds the predetermined reference value with which it is compared, the one that so exceeds by the greatest margin is selected. A command current limit factor is derived from the selected filtered motor load signal and used to limit the commanded motor current. The motor load signal preferably indicates motor operating current and may be derived from a motor current sensor or from the limited command current signal, motor speed and operating voltage to compensate for a decrease of current with motor speed due to inductance/slope compensation and voltage limit effects.