AC motor vs. DC motor efficiency

[nlpolk]

I am currently using a 600HP DC motor for an extruder application and I am exploring the idea of switching to a 600HP AC motor. What kind of energy savings/efficiency can I expect if any?

 

[milesyoung]

That's a very hard question to answer without knowing more about the specifics of the motor you currently have installed and the one you're looking to switch to, including how you're going to run/control them.

All things being equal, 3 phase AC machines will generally have a higher efficiency than mechanically commutated DC machines in your power range.