Compressor surge control with pressure rate of change control

摘要

A surge control system for controlling and preventing a surge condition and a method of controlling surge in a fixed or variable speed compressor or a compressor having a variable geometry which provides air to a pneumatic load. A transducer provides a signal proportional to the outlet pressure of the air from the compressor. The signal is differentiated with respect to time and if a surge condition is ensuing, the absolute value of the differentiated signal is greater than a reference. When the differentiated signal is greater than the reference, a portion of the air supplied to the load is vented to reduce the outlet pressure. A reduction in the outlet pressure alleviates the ensuing surge condition and the absolute value of the differentiated signal decreases, causing the venting valve to close.