Modern Electrical Drives: An Overview

Abstract

An electrical drive, as shown in Fig. 1.1 can be defined in terms of its ability to efficiently convert energy from an electrical power source to a mechanical load. The main purpose of the drive is to control a mechanical load or process. The direction of energy flow is generally from electrical to mechanical, i.e., motoring mode with power flow from the power source to the mechanical load via the converter and machine as shown in Fig. 1.1. However, the energy flow can in some cases be reversed, in which case the drive often is configured bi-directional to also allow energy flow from the mechanical load to the power source, i.e., generating mode. Modern electrical drives, as considered in this book, utilize power electronic devices to (digitally) control this power conversion process, a feature which is highlighted in Fig. 1.1 by the presence of the modulator and controller unit.Fig. 1.1.