Here is a book for electric drives and traction.
Electric motors are so much a part of everyday life that we seldom give them
a second thought. When we switch on an ancient electric drill, for example, we
confidently expect it to run rapidly up to the correct speed, and we don’t question
how it knows what speed to run at, or how it is that once enough energy has been
drawn from the supply to bring it up to speed, the power drawn falls to a very low
level. When we put the drill to work it draws more power, and, when we finish, the
power drawn from the mains reduces automatically, without intervention on our