Chapter List

Introduction

Thus far, we have focused mainly on the use of microcontrollers and analog bipolar IC devices in motor controls. In this chapter our main concern will be with the discrete semiconductor devices (IGBTs, MOSFETs, rectifiers, etc.) that are commonly employed in motor drives. An understanding of the semiconductor data sheet will also be presented with an emphasis on how this information relates to a motor control design. Other issues, such as packaging, semiconductor materials, and ESD, will be discussed as well.

13.1 Semiconductor Overview

Electronic motor drives have been made possible by the development of new solid-state devices, as seen in Fig. 13.1. Large MOSFET and IGBT power devices are readily available that can switch significant amounts of power with the ability to block line voltages of 480 V or greater. In this section we will look at semiconductors that perform vital functions in motor drives, especially the high-power devices, as well as some low-power signal devices. These include diodes, transistors, and thyristors. Examples pertain, for the most part, to three-phase induction motors but are applicable to other motor drive technologies, including DC and brushless DC motor drives. An upcoming motor drive technology is switched reluctance, and, although this topology does not require the same degree of short-circuit protection, much of the semiconductor...