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. 11, 1976
Filed:
Oct. 21, 1974
John P Walden, Schenectady, NY (US);
General Electric Company, Schenectady, NY (US);
Abstract
An AC electrical output is produced in the secondary windings of a transformer by alternately switching DC current in a primary winding with active element switches whose alternate switching action is controlled by the stored energy variations in a tertiary winding included with the output transformer and by a high efficiency switching control circuit which facilitates the switching transition of the active elements. This control is achieved in part, by providing a current sensitive latch which is triggered to its conductive state when a predetermined level of primary winding current is detected to thereby initiate a switching transition. This latch circuit is connected to conduct stored electrical charge with respect to the active element switch during the switching transition thus facilitating and promoting the efficiency of the switching operation. In addition, this same current sensitive latch is utilized to terminate normal inverter operations during excessive inverter load conditions and/or in response to detected excessive operation temperatures. In this latter regard, a special thermal protection circuit is employed for triggering the current sensitive latch. The special form of thermal protection circuit is especially adapted to protect integrally formed integrated circuits and is itself integrally formed therewith in a preferred embodiment. The thermal protection circuit includes a temperature sensitive element having a predetermined voltage versus temperature variation at a given current level in combination with a current regulation circuit for supplying and substantially maintaining a predetermined current level through the temperature sensitive element. A special form of periodic restarting circuit is also disclosed wherein another current sensitive latch is utilized to provide periodic starting pulses in the absence of normal inverter operation and to supplement control circuit and switching circuit supply currents during normal inverter operations.