Power Electronics for Renewable Energy Systems, Transportation and Industrial Applications

Chapter 10Properties and Control of a Doubly Fed Induction Machine

Gonzalo Abad¹ and Grzegorz Iwanski²

¹Electronics and Computing Department, Mondragon University, Mondragon, Spain

²Institute of Control and Industrial Electronics, Warsaw University of Technology, Warszawa, Poland

10.1 Introduction. Basic principles of DFIM

10.1.1 Structure of the Machine and Electric Configuration

The doubly fed induction machine (DFIM) or wound rotor induction machine (WRIM) are terms commonly used to describe an electrical machine, which has been used over many decades in various applications, often in the range of megawatts of power and also less commonly in the range of a few kilowatts. This concept of the machine is as an alternative to more common asynchronous and synchronous machines. It can be advantageous in applications that have a limited speed range, allowing a reduction in the size of the supplying power electronic converter as, for instance, in variable-speed generation, water pumping and so on.

The typical supply configuration of the DFIM is shown in Figure 10.1. The stator is supplied by three-phase voltages directly from the grid at constant amplitude and frequency, creating the stator magnetic field [1 2]. The rotor is also supplied by three-phase voltages that take a different amplitude and frequency at steady state in order to reach different operating conditions of the machine (speed, torque, etc.). This is achieved by using a back-to-back three-phase converter, as represented ...