Medium-Voltage Adjustable-Speed-Drive Retrofit of an Existing Eddy-Current Clutch Extruder Application

This paper describes a recent case study of replacing an eddy-current clutch with a modem medium-voltage adjustable-speed drive (ASD) for a 2250-hp extruder application. It covers key issues, justification, factory and field measurements of torque-speed profile from 0.5 to 60 Hz, as well power quality analysis. The paper reviews manufacturers' capability to build medium-voltage ASDs that produce very high and stable torque at very low speed. Index Terms--Adjustable-speed drives, drive topologies, extruder.