Electric Motors and Drives, 4th Edition

Chapter Five

Induction Motors – Rotating Field, Slip and Torque

1. Introduction

Judged in terms of fitness for purpose coupled with simplicity, the induction motor must rank alongside the screwthread as one of mankind’s best inventions. It is not only supremely elegant as an electromechanical energy converter, but is also by far the most important, with something like half of all the electricity generated being converted back to mechanical energy in induction motors. Despite playing a key role in industrial society, it remains largely unnoticed because of its workaday role driving machinery, pumps, fans, compressors, conveyors, hoists, and a host of other routine but vital tasks. It will doubtless continue to dominate fixed-speed applications, ...