STABILITY CONTROL SYSTEM AND METHOD FOR CENTRIFUGAL COMPRESSORS OPERATING IN PARALLEL

摘要

A control system is provided to maintain stable operating conditions forcentrifugal compressors operating in parallel when one of the centrifugalcompressorsenters into an unstable operating condition. The control system determines anunstable operating condition in response to signals indicating the motorcurrent orpower consumption of each compressor and the position of the pre-rotationvanes ofthe compressors. Once an unstable operating condition is determined, thecontrolsystem closes the pre-rotation vanes to each compressor until the unstableoperatingcondition has been corrected.