A Novel Approach for Active Surge Control in Multistage Centrifugal Compressor

Compressors are used in the hydrocarbon industry from upstream to downstream to boost the pressure required to transport gas into processing and transportation pipelines inside and toward processing facilities. Turbo-centrifugal compressors are subject to repetitive damages resulting from the manifestation phenomenon known as surge, observed as fluid flow reversal at low mass flows. Active surge control aims to increase the compressor operating region by allowing the compressor to operate at low mass flow in the naturally-unstable region of the compressor. Surge is avoided in the industry by forcing the operating point to the stable region of the compressor curve. Active surge control aims to control the surge phenomenon by extending the stable operating region. This work developed a novel model-based control approach for effective compression system active surge control on an automatic coupled recycle valve as a primary actuator. The feedback linearization technique is used to reduce the system complexity by providing a linear representation of the highly nonlinear system. A detailed description of the feedback linearization method for centrifugal compressors and a dual controller design was developed in this paper.