Power generating system and its control method

Patent 7304400 Issued on December 4, 2007. Estimated Expiration Date:

December 25, 2023. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

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Inventors

Assignee

Kabushiki Kaisha Yaskawa Denki

Application

No. 10539009 filed on 12/25/2003

US Classes:

290/44, Wind290/52, TURBOGENERATORS322/29, Speed or frequency of generator318/800, With controlled power conversion322/32, Frequency responsive devices or networks363/89, With transistor control means in the line circuit290/55, Wind322/17, AUTOMATIC CONTROL OF GENERATOR OR DRIVING MEANS322/89, With armature or primary circuit control290/10, With starting and generating dynamo318/802, Responsive to an additional condition318/439, MOTOR COMMUTATION CONTROL SYSTEMS700/297Power supply regulation operation

Examiners

Primary: Schuberg, Darren
Assistant: Cuevas, Pedro J.

Attorney, Agent or Firm

Sughrue Mion Pllc.

Foreign Patent References

9-191698 JP 07/01/1997
2002-34298 JP 01/01/2002
2002-84797 JP 03/01/2002

International Classes

H02P 9/00
H02P 9/10
H02P 9/14
F03D 7/00

Abstract

A power controller 5 calculates the induced voltage or rotor magnetic flux from the output voltage and the output current of a generator 3, estimates a shaft speed of the generator 3 from the phase of the induced voltage or the phase of the rotor magnetic flux, and calculate the output of a windmill 1 from the estimated value of the shaft speed and the output of the generator 3. As a result, since the output of the windmill 1 can be calculated without requiring a speed sensor for detecting the shaft speed of the generator 3, it is possible to accomplish simplification of circuits, reduction of cost, and high reliability.