System for supression of underdamped oscillations in a.c. power drawn by synchronous motors driving ward leonard generators
CA 1201159 A · Owner: Broken Hill Proprietary Company Limited (The) · Inventors: Godfrey, Noel R.; Parkes, Larry S.; Treacy, Richard H.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method and apparatus for reducing oscillations in input electrical power to a Ward- Leonard drive system which is subject to variations in mechanical loading, the technique utilizing a notch filter in the feedback path to the dc generator the notch filter being turned to match the resonant frequency of the synchronous motor.
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Granted February 25, 1986. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 25, 2003.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.