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:
Apr. 24, 1979
Filed:
Feb. 21, 1978
Shigehiko Suzuki, Inazawa, JP;
Satoshi Imaiida, Inazawa, JP;
Abstract
The present invention is an induction motor control system which prevents an excessive induced voltage across the thyristors providing DC braking control. The amount of DC braking torque is controlled by the time of application of the DC braking voltage to the induction motor through a phase-control capacitor which sets the time of firing the braking thyristors within each half cycle of the AC voltage. In a first embodiment the firing of all the braking thyristors is inhibited upon application of the DC braking control signal until the half cycle of the AC voltage associated with a predetermined braking thyristor. In a second embodiment the firing of a predetermined braking thyristor is inhibited during the half cycle of the AC voltage of the application of the DC braking control signal and the next succeeding half cycle. In both embodiments the braking thyristors are fired during their associated half cycle of the AC voltage thereafter to apply a continuing DC braking voltage to the induction motor.