Electric Machines and Drives

8

Power Electronic Circuits for Electric Motor Drives

8.1 Introduction

In Chapters 3, 4, 5, 6 and 7, we laid out drive strategies for ac and dc machines. It was noted that the practical implementation of these drives requires sources that control the terminal variables of the machines, such as voltage or current magnitudes or frequency. We treated these controlled sources as black boxes as their internal circuitry and the way they are controlled to achieve the desired output voltage or current do not affect the strategy adopted for the drive.

In this chapter, we study the practical power electronic circuits that are used to craft controlled voltages and currents at the terminals of dc and ac machines. At the heart of every power electronic ...