Method and apparatus for direct torque control of a three-phase machine
CA 2199080 C · Owner: Abb Schweiz Ag · Inventors: Pohjalainen, Pasi; Stulz, Christian
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method and an apparatus for direct torque control are specified for a three-phase machine fed via a harmonic filter, which method manages as far as possible without any major adaptation to already known DTC methods and DTC apparatuses. In addition the, oscillations caused by the filter are intended to be damped effectively. This is achieved in that a current flowing through the filter and/or a filter output voltage are/is measured, and the reference flux value and the reference torque value are corrected on the basis of the measured voltage and/or of the measured current. The correction comprises a transformation of the filter output voltage into a first component at right angles to a …
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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
- Filed March 4, 1997 and granted November 5, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 4, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 4, 2019.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.