Cycloconverters such as Nidec’s SILCOVERT C drives are typically used where highpower, relatively low variable frequency three-phase currents are needed to operate variable speed motors. While the 15-plus-year old cycloconverters at this steel mill still had significant life remaining, Nidec extended their life and improved their reliability with a state-of-the-art ARTICS control system.
To enable the mill to use either the old or new controls and motor exciters, Nidec installed a cold backup system that could switch power and signal cables from one system to the other in under 15 minutes.
Nidec’s other services included system and installation engineering, system erection, commissioning the Automation PLC Porting and training staff on the system’s operation. The completed system today provides stable and reliable performance, while working near the maximum admissible torque – more than 225% of the motor’s rated torque – required by the mill’s main stand.