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:
Jan. 15, 1985
Filed:
Mar. 05, 1982
David A Bailey, Torrance, CA (US);
The Garrett Corporation, Los Angeles, CA (US);
Abstract
A control circuit for a brushless DC motor providing positive control in all four quadrants of motor operation. The circuit provides control of motor current, thereby controlling motor torque, in response to an applied current command signal, relying solely on feedback signals of motor current and rotor angle. The heart of the system is a level dependent logic stage which selectively controls the states of the switches applying power to the motor windings in accordance with a current error signal developed by reference to the feedback current signal. The control circuit causes the motor current to correspond to any applied current command and works at any motor speed and torque for rotation in either direction. In a preferred embodiment, the basic control system is combined with additional feedback loops developing servo information regarding rate and actuator position to provide a overall position control system, such as is particularly useful in place of the hydraulic actuator systems now employed in aircraft.