A multi-stage fluid compression system includes a first centrifugal
compressor stage having a first inlet and a first outlet and a second
centrifugal compressor stage having a second inlet and a second outlet.
The second inlet receives a flow of compressed fluid from the first
outlet. A first variable-speed motor is coupled to the first centrifugal
compressor stage and is operable to drive the first centrifugal
compressor stage at a first speed. A second variable speed motor is
coupled to the second centrifugal compressor stage and is operable to
drive the second centrifugal compressor stage at a second speed. The
first speed and the second speed are each independently variable.