Large synchronous motors for the Delaware City repowering project

The successful and profitable operation of a petroleum coke gasification project relies very heavily on a reliable source of oxygen produced from an air separation unit (ASU). The ASU for the Motiva Delaware City repowering project depends upon the proper application and operation of very large synchronous motors, including a four-pole 66000-hp machine and a four-pole 43000-hp machine, the former being the largest 1800-r/min compressor driver ever designed and manufactured. Specification development and supplier selection are summarized. The effects of motor starting on the power system with regard to voltage drop are outlined and discussed. Motor design issues relating to transient temperatures and stresses as well as torsional and lateral critical speeds are analyzed. Factory and commissioning test procedures that verify the motor electrical design, mechanical design and performance are discussed.