Features of a Power System Incorporating Large AC Motors/Captive Transformers

Both synchronous and induction motors driving fans, pumps, and compressors (variable torque types of loads) may prove to be more economical and reliable when utilizing a lower voltage motor plus a captive transformer rather than a 13.8-kV motor. The economic factors, matching motor capabilities to load requirements, power system considerations, relaying and grounding systems possibilities, and operating experience with installed drives in Atlantic Richfield´s Philadelphia Refinery are covered.