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:
Aug. 23, 2011
Filed:
Aug. 06, 2008
Mark E. Hartman, Peoria, IL (US);
Jesse R. Gerdes, Dunlap, IL (US);
Gregory J. Speckhart, Peoria, IL (US);
Jackson Wai, Dunlap, IL (US);
Mark E. Hartman, Peoria, IL (US);
Jesse R. Gerdes, Dunlap, IL (US);
Gregory J. Speckhart, Peoria, IL (US);
Jackson Wai, Dunlap, IL (US);
Caterpillar Inc., Peoria, IL (US);
Abstract
A method of detecting one or more failed current sensor and estimating a phase current for the failed current sensor on a three-phase machine is disclosed. The method may include detecting one or more failed current sensor by determining if an absolute value of a sum of the phase currents of the motor is below an open circuit value. The method may also include determining which phase currents are approximately zero, for each phase current associated with each phase of the motor, if the sum of the phase currents of the motor is not below the open circuit value. The method may further include estimating the phase current for the failed current sensor by determining the phase current value for the failed current sensor, that when added to the phase currents of the remaining current sensors, will make the sum of all the phase currents equal to approximately zero.