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:
Feb. 12, 2019
Filed:
Apr. 03, 2014
Ihi Corporation, Tokyo, JP;
Tsuneo Koki, Tokyo, JP;
Naoki Nishiyama, Tokyo, JP;
Yuji Echizen, Tokyo, JP;
Takashi Oyabu, Tokyo, JP;
Tomonori Seki, Tokyo, JP;
Masashi Moriguchi, Tokyo, JP;
IHI Rotating Machinery Engineering Co., Ltd., Tokyo, JP;
Abstract
There is provided a centrifugal compressor apparatus including a centrifugal compressor that centrifugally compresses a gas, an electric motor that rotatably drives the centrifugal compressor, a current detector that detects a drive current I of the electric motor, and an exhaust valve that discharges a compressed gas to a lower pressure section. The centrifugal compressor apparatus (A) detects the drive current I at a sampling cycle ts, (B) updates, as a current threshold, in real time, a value '(moving average)−n×(standard deviation)' for which a plurality of drive currents measured in a sampling period tp serves as a population, where n is a positive number in the range of 3 to 4 and, (C) determines that surging has occurred when the exhaust valve is closed and the drive current I is below the current threshold X, and (D) further opens the exhaust valve to discharge the compressed gas when determining that surging has occurred.