Induction motors aren’t going away any time soon. In fact, they just keep getting better as improved materials continue to make possible more-efficient designs. At some point the law of diminishing returns kicks in. With motors operating in the 90%-plus efficiency range for most ratings, there isn’t much more room for improvement. Laws of physics make it prohibitive to design ac-induction motors with higher efficiencies.
In recent months, we’ve discussed some weighty issues in this column, including space exploration and the jobless recovery. Many of you have contacted us with interesting responses and perspectives. That’s just the kind of interaction that spurs ideas and advances society. However, summer has arrived, bringing with it a chance to lighten up a little