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. 30, 2017
Filed:
Apr. 05, 2013
Minebea Co., Ltd., Nagano, JP;
Martin Winker, Wurmlingen, DE;
Klaus Moosmann, Schramberg, DE;
MINĖBEA CO., LTD., Miyota-Machi, Kitasaku-Gun, Nagano, JP;
Abstract
The invention describes a method for controlling a sensorless, brushless DC motor that is controlled via a bridge circuit preferably using pulse width modulation (PWM) having precommutation. According to the invention, in the braking operation each commutation interval is divided into two phases. A drive phase, lasting from the start of the commutation interval up to zero crossing in which the motor is controlled with the normal PWM, and a braking phase, lasting from zero crossing up to the next commutation time in which at least two motor phases are short-circuited and/or in which the PWM is operated with recovered energy. The efficiency of the control circuit is as low as possible so as to ensure that the braking energy is consumed in the control circuit.