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:
Jul. 09, 2013
Filed:
May. 08, 2009
Kazunobu Oi, Tokyo, JP;
Masakazu Muneshima, Tokyo, JP;
Akihiro Kimura, Tokyo, JP;
Meidensha Corporation, Tokyo, JP;
Abstract
A self-contained control unit of a system stabilizing device installed on a microgrid is provided with a fluctuation detecting blockA for determining a fluctuation component of the frequency of system voltage (Cωs) and a fluctuation component of voltage amplitude of the system voltage (C|Vs|). The fluctuation detecting blockA determines the fluctuation component (Cωs) based on a deviation between the output signal of a low-pass filterfor noise removal and the output signal of a low-pass filterfor determining a fluctuation detection time. An interference action inhibiting unitjudges whether system stabilizing control and governor control of a generator interfere with each other, based on a frequency signal ωs and the fluctuation component Cωs. If there is interference, the time constant of the low-pass filteris reduced to reduce the fluctuation component Cωs, thereby decreasing the amount of control by the system stabilizing device and preventing interference. By this measure, system stabilizing control is exercised, without interfering with the governor control or AVR control of the generator.