PROJECT TITLE :

Synchronous Motors on Grinding Mills: The Different Excitation Types and Resulting Performance Characteristics with VFD Control for New or Retrofit Installations

ABSTRACT:

Synchronous motors (SMS) continue to be a viable alternative to induction motors as a result of of efficiency benefits. Since SMs have long been used to produce leading kvar for power factor (PF) improvement and to assist with the device switching in load-commutated inverter (LCI) drives, these machines are economical prime movers for large mill applications. Both in motor potency and in low-base-speed configurations, the SM has benefits of lower current and better efficiency. Typically employed in large mills in the cement and mining business, these motors were driven by LCI variable-frequency drives (VFDs) or used with direct start with a clutch system that would synchronize the motor 1st to overcome low beginning torques. This article reviews various mill drive configurations and improved SM characteristics when used with advanced drives. It can conjointly review the various SM excitation varieties and resulting performance characteristics with VFD management for brand new or retrofit installations.