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:
Feb. 06, 1996
Filed:
Sep. 16, 1993
William A Harris, Coon Rapids, MN (US);
Honeywell Inc., Minneapolis, MN (US);
Abstract
A pulse width modulation controller particularly useful for a variable speed variable torque electric motor. Inputs to the controller are a desired RPM signal, a motor electrical signal which is a function of the RPM of the rotor of the motor and its angular position relative to the stator, and a torque feed back signal derived from the power phase winding circuits of the motor. The controller produces pulse width modulated power drive signals which are applied to power switches of the power phase winding circuits of the motor to allow electric current to flow through the power phase winding circuits when power phase enable signals produced by the controller sequentially enable the power switch of a power phase winding circuit to do so. The duty cycle of the power drive signals is a function of the difference between the desired and actual RPM of the motor and the torque of the motor. The frequency of the power drive signals is a fixed integral multiple of the frequency of the power phase enable signals over the full operating range of RPMs of the motor.