Re:Why didn't electricity immediately change manufacturing?
by Animats on Monday August 21, 2017 @02:07PM
(#15066381)
No, steel mill drives in both AC and DC were used.[1] They each have their advantages.
Speed control in the early days took additional rotating electrical machinery. Huge rotating machinery.
Diesel-electric locomotives mostly used DC motors in the 20th century. 3-phase AC synchronous motors with elaborate semiconductor control systems are now used in most new locomotives, but that's only in the last 20 years.[2] There are still thousands of DC-motor locomotives running on US rails.
High-speed elevators were DC for most of the 20th century.
Speed control of DC motors was, for a long time, easier than speed control for AC motors. The reverse is now true, because power semiconductors are so good.
Diesel-electric locomotives mostly used DC motors in the 20th century. 3-phase AC synchronous motors with elaborate semiconductor control systems are now used in most new locomotives, but that's only in the last 20 years.[2] There are still thousands of DC-motor locomotives running on US rails.
High-speed elevators were DC for most of the 20th century.
Speed control of DC motors was, for a long time, easier than speed control for AC motors. The reverse is now true, because power semiconductors are so good.
[1] https://books.google.com/books?id=-thQAAAAYAAJ&pg=PA308 [2] http://www.republiclocomotive.com/ac-traction-vs-dc-traction...