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:
May. 17, 2011
Filed:
Apr. 18, 2008
Christian Paintz, Ypres, BE;
Thomas Freitag, Ypres, BE;
Detlef Klose, Ypres, BE;
Melexis NV, Ypres, BE;
Abstract
In order to determine the orientation of the rotor of a brushless DC motor, a sequence of current pulses may be applied to the stator phases U, V, W by the respective drivers HS, LS, HS, LS, HS, LS. The current generated in the stator phases U, V, W in turn generates a current in a shunt resistor. The current in this shunt resistoris monitored by use of a current voltage converterand a comparatorto determine when it exceeds a predetermined threshold. The rise time until the threshold current is exceeded is recorded in capture unit. A processor unitthen calculates a scalar parameter SU, SV, SW for each respective stator phase U, V, W from the recorded rise times associated with each pulse. The orientation of the magnetic axis of the rotor can then be determined by consideration of the scalar parameters SU, SV, SW of each stator phase U, V, W, as the respective rise times of each pulse are determined by the inductive properties of the respective stator phases U, V, W, which in turn are dependent upon the orientation of the rotor.