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. 03, 2006
Filed:
Aug. 07, 2002
Alexander Hahn, Sauldorf-Boll, DE;
Walter Heydrich, Georgen, DE;
Hermann Rappenecker, Vöhrenbach, DE;
Alexander Hahn, Sauldorf-Boll, DE;
Walter Heydrich, Georgen, DE;
Hermann Rappenecker, Vöhrenbach, DE;
ebm-papst St. Georgen GmbH & Co. KG, St. Gerogen, DE;
Abstract
The invention concerns a method for operating an electronically commutated motor () that is equipped with a current limiting arrangement which acts on a PWM controller (). The latter, in operation, delivers PWM pulses () having a controllable pulse duty ratio (pwm) and a substantially constant frequency. In the event a predetermined upper limit value (I; I) of the motor current (I) is exceeded, the current limiting arrangement effects a change in this pulse duty factor (pwm) in order to reduce the motor current (I). If the motor current (I) exceeds a predetermined upper limit value (I; I) while the motor () is rotating, that limit value (I; I) is raised by a timing member () during a predetermined time span () (FIG.: I), so that the available motor power is temporarily raised in the context of a load peak. If the rotor () is stalled, the limit value (I) is not raised but instead is greatly lowered. The limit value (I) is preferably raised as a function of the rotation speed of the motor () in order to utilize the improved motor cooling at high rotation speeds. At start-up of the motor (), the limit value (I) is briefly increased to a high value in order to enable dependable starting.