1
Gregory K Beaverson, Bart A Smith: System and method for controlling an HVAC system using a flash mini-card. York International Corporation, Finnegan Henderson Farabow Garrett & Dunner L, December 18, 2001: US06330806 (101 worldwide citation)

A heating, ventilation, and air-conditioning (HVAC) control system and method for controlling a device, a subsystem, and/or a process using a flash mini-card. Preferably, the present invention is directed to an HVAC control system and method for controlling a chiller and the devices and subsystems a ...


2
Gregory K Beaverson, Russell P Wueschinski, Craig N Shores, John C Hansen: Variable speed control of a centrifugal chiller using fuzzy logic. York International Corporation, Finnegan Henderson Farabow Garrett & Dunner L, September 23, 1997: US05669225 (32 worldwide citation)

To capacity control a refrigeration system including a compressor, a condenser, and an evaporator all connected in a closed refrigeration circuit, the compressor having a plurality of adjustable inlet guide vanes and driven by an internal combustion engine, signals indicating the condenser pressure; ...


3
Gregory K Beaverson, Harold B Ginder, Dennis L Deitz, Sakin R Cakmakci: Hot gas bypass control for centrifugal chillers. York International Corporation, Finnegan Henderson Farabow Garrett & Dunner, August 6, 2002: US06427464 (32 worldwide citation)

Methods and systems consistent with this invention control a hot gas bypass valve in a refrigeration system including a centrifugal compressor, a condenser, an evaporator, and a hot gas bypass line between the compressor and the evaporator. Such methods and systems continuously sense for a surge con ...


4
Gregory K Beaverson, Harold R Schnetzka, Timothy M Frank: Methods and apparatuses for detecting surge in centrifugal compressors. York International Corporation, Finnegan Henderson Farabow Garrett & Dunner L, April 20, 1999: US05894736 (22 worldwide citation)

A surge detection system for use in a fluid system having a load driven by a centrifugal compressor, the compressor being driven by an electric motor. The surge detection system comprises a means for sensing a differential pressure developed across the compressor and a means for sensing a current re ...


5
Gregory K Beaverson: Apparatus and method for correcting CCD pixel nonuniformities. RCA Corporation, E M Whitacre, D H Irlbeck, L L Hallacher, October 6, 1987: US04698685 (21 worldwide citation)

Nonuniformities in the pixel of a CCD are corrected by storing a correction value for every pixel of the CCD. The pixel values from the CCD are transferred to a multiplier. The correction values are also transferred to the multiplier in synchronization with the transfer of the pixel values. The corr ...


6
Gregory K Beaverson, Harold R Schnetzka, Timothy M Frank: Methods and apparatuses for detecting surge in centrifugal compressors. York International Corporation, Finnegan Henderson Farabow Garrett & Dunner L, May 5, 1998: US05746062 (15 worldwide citation)

A surge detection system for use in a fluid system having a load driven by a centrifugal compressor, the compressor being driven by an electric motor. The surge detection system comprises a means for sensing a differential pressure developed across the compressor and a means for sensing a current re ...


7
Gregory K Beaverson, Harold B Ginder, Dennis L Deltz: Adaptive hot gas bypass control for centrifugal chillers. York International Corporation, Finnegan Henderson Farabow Garrett & Dunner L, March 20, 2001: US06202431 (13 worldwide citation)

An adaptive control apparatus and a method for automatically controlling a refrigeration system as a function of cooling load and head. A control panel controls the operation of a hot gas bypass valve so as to avoid surging of the compressor in response to cooling load and head. The control apparatu ...


8
Gregory K Beaverson, Wanda J Miller: Self-tuning pull-down fuzzy logic temperature control for refrigeration systems. York International Corporation, Brian T Sattizahn, Carmen Santa Maria, McNee Wallace & Nurick, September 16, 2003: US06619061 (12 worldwide citation)

A pull-down control algorithm for an HVAC refrigeration system is provided. The control algorithm utilizes a fuzzy logic methodology to automatically adjust a flow of refrigerant in the system during a pull-down to maintain a desired pull-down rate. The desired pull-down rate is decreased proportion ...


9
Gregory K Beaverson, Craig N Shores, Russel P Wueschinski: Fuzzy logic liquid level control. York International Corporation, Finnegan Henderson Farabow Garrett & Dunner L, September 22, 1998: US05809795 (10 worldwide citation)

Chiller operating efficiency is optimized by controlling the system to maintain the condenser liquid refrigerant level at a value which will minimize or prevent gas bypass to the evaporator. This is accomplished by sensing the level of liquid refrigerant in the condensor and incorporating fuzzy logi ...


10
Gregory K Beaverson, Harold B Ginder, Dennis L Deitz, Sakin R Cakmakci: Hot gas bypass control for centrifugal chillers. York International Corporation, Finnegan Henderson Farabow Garrett & Dunner, February 17, 2004: US06691525 (4 worldwide citation)

Methods and systems consistent with this invention control a hot gas bypass valve in a refrigeration system including a centrifugal compressor, a condenser, an evaporator, and a hot gas bypass line between the compressor and the evaporator. Such methods and systems continuously sense for a surge con ...