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. 06, 2004
Filed:
Nov. 20, 2001
Joerg Sutter, Gaggenau, DE;
Wolfgang Schwenk, Oberkirch-Tiegarten, DE;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
The present invention provides a method for shifting the instant of commutation for a sensorless and brushless direct-current motor ( ), whose stator windings are fed by a multi-phase converter connection. The converter connection includes an output stage control ( ), a commutation logic ( ), a phase selector ( ), and phase discriminator ( ). A commutation detection ( ) is supplied at one input ( ) with the instantaneous value of the voltage induced in a phase, the instantaneous value being determined by the phase selector, and at a second input ( ), with a reference voltage (U ) for comparison. The reference voltage (U ) can be changed by a commutation shift ( ) in correspondence with a specific characteristic curve ( ). A manipulated variable (U ) is supplied by a manipulated-variable calculation ( ) to the commutation shift ( ) as a function of the setpoint speed (N ) of the motor. The commutation shift takes place in an advantageous manner in a parabola shape. As a result of the setpoint value-dependent commutation shift, a high torque is provided also in the case of high rotational speeds and a heavy load, and the torque ripple is kept to a minimum.