Antisurge Performance Control（Antisurge 性能控制）.pdf

Antisurge Performance Control CCC Fact Sheet An axial or centrifugal compressor can be severely damaged if process conditions reduce its gross flow below a minimum surge limit, and can also be damaged by conditions that would require flow rates in excess of a maximum choke limit. Each compressor needs an Antisurge Control Application to protect it from surge (and choke) and a Performance Control Application to regulate its capacity. Antisurge Control Application (AS) The only way to prevent surge is to recycle or blow off flow to keep the operating point away from the surge limit. Because compressing this extra flow entails an economic penalty, the control system must accurately determine how close the compressor is to surging and then maintain an adequate but not excessive flow rate. Our unique combination of surge prediction and antisurge control algorithms protect your machines with the smallest possible recycle rates. The surge limit is not fixed relative to any one measurable variable. Instead, it is a complex function that depends on gas composition, temperatures, pressures, speed, and guide vane angle. Thus, the antisurge control program calculates proximity-to-surge using a multivarible function that is invariant to any process change it might encounter. Because that function depends on which conditions are fixed and the configuration of your compressor, we provide a flexible method for defining it. The anti-surge control program also offers high or low limiting loops that maintain up to three single or multiple input process limiting variables. A performance control application can regulate simple pressure or flow measurements, the compression ratio, or a pressure and temperature compensated mass flow. It can also implement high or low limiting loops for up to three single or multiple input variables. In addition to decoupling its