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, 2017
Filed:
Jun. 20, 2016
Nidec Motor Corporation, St. Louis, MO (US);
Robert K. Hollenbeck, Fort Wayne, IN (US);
Nidec Motor Corporation, St. Louis, MO (US);
Abstract
An electrical motor controller changes the PWM frequency that is used by a motor driver to form the fundamental frequency and voltage magnitude for the electrical power delivered to an electrical motor. The electrical motor controller compares a signal generated by a first sensor that indicates an output speed of the motor to a predetermined speed threshold and compares a signal generated by a second sensor that corresponds to phase currents in the electrical motor to a predetermined motor power threshold. These comparisons are used to set the PWM frequency for the motor driver. The PWM frequency either corresponds to a frequency in a humanly imperceptible audio range or to a frequency that is in a humanly perceptible audio range.