Ten years of operating experience with a 15000 hp, 6000 r/min adjustable speed drive system

This paper is the sequel to a previous paper presented at the IEEE PCIC conference in 1994 [Wood, B et al., 1995]. The original paper focused on the design, testing, and commissioning of the 15000 hp adjustable speed drive (ASD) system. This paper describes the operating experience of this ASD system during its first ten years of service. Several unplanned trips of the ASD, two failures of the input transformer, failure of the motor lead cables, and overheating of the motor that led to its eventual replacement are discussed. The incidents are described, the root causes are examined, the corrective measures are discussed, and the lessons learned are presented. The success of the ASD in dealing with the many utility voltage disturbances experienced by the refinery electrical system is also addressed.