DEVELOPMENTS IN CENTRIFUGAL-COMPRESSOR SURGE CONTROL - A TECHNOLOGY-ASSESSMENT

There are a number of surge control schemes in current use for centrif ugal compressors employed in natural gas transmission systems. Basical ly, these schemes consist of a set of detection devices that either an ticipate surge or detect it at its inception, and a set of control dev ices that act to prevent surge from occurring. A patent search was con ducted in an attempt to assess the level and direction of technology d evelopment over the last 20 years and to define the focus for future R &D activities. In addition, the paper presents the current state of te chnology in three areas: surge control, surge detection, and surge sup pression. Patent data obtained from on-line databases showed that most of the emphasis has been on surge control rather than on detection an d control and that the current trend in surge control will likely cont inue toward incremental improvement of a basic or conventional surge c ontrol strategy. Various surge suppression techniques can be grouped i n two categories: (i) those that are focused on better compressor inte rior design, and (ii) others that attempt to suppress surge by externa l and operational means.