Harmonic torque considerations of applying a 6000-HP induction motor and drive to a high-speed compressor

This paper discusses the causes and effects of torsional harmonics in adjustable frequency induction motor drives, describes some electrical and mechanical methods used to mitigate potentially harmful effects, describes methods of predicting torsional harmonic levels, describes methods of measurement of torsional harmonics, and compares the measured and predicted levels for a particular 6000-HP centrifugal compressor application at the Shell Hamburg Gas Plant, Alabama, using a PWM CSI induction motor drive.