Patent ID: 11946678
Assignee: COPELAND LP
Field: Thermal processes and apparatus (Mechanical engineering)
Classification: CPC F  Y | IPC F

Claim 10:
11. A controller for a dynamic compressor having a motor, a first compressor stage driven by the motor, and a second compressor stage driven by the motor, the controller comprising:
a processor; and
a memory, the memory storing instructions that program the processor to:
operate the dynamic compressor at a current speed, a first position of a first variable inlet guide vane (VIGV) of the first compressor stage, and a second position of a second VIGV of the second compressor stage to compress a working fluid, the first VIGV being controllable to selectively introduce pre-whirl into working fluid entering the first compressor stage and the second VIGV being controllable to selectively introduce pre-whirl into working fluid entering the second compressor stage;
determine, while operating the dynamic compressor, if a condition is satisfied;
continue to operate the compressor at the current speed, the first position of the first VIGV, and the second position of the second VIGV when the condition is not satisfied; and
change the second position of the second VIGV to a third position different than the second position and maintain the first position of the first VIGV when the condition is satisfied, wherein determining if the condition is satisfied comprises determining if a valve is open, the valve being in fluid communication with the dynamic compressor to selectively direct a flow of working fluid to an inlet of the second compressor stage without the flow of working fluid passing through the first compressor stage.