The purpose of this paper is to reinforce with theoretical and experimental evaluation the effectiveness of employing an induction generator to enhance the performance of a small wind energy converter (SWEC). With this generator, the SWEC works more efficiently and therefore can produce more energy in a unit turbine area. To verify the SWEC performance, a model has been proposed, simulated, built, and experimentally tested over a range of operating conditions. The results demonstrate a significant increase in output power with an induction generator that employs an auxiliary winding, which is only magnetically coupled to the stator main winding. It is also shown that the operating performance of the induction machine with the novel proposed technique is significantly enhanced in terms of suppressed signal distortion and harmonics, severity of resistive losses and overheating, power factor, and preventing high inrush current at starting. 1. Introduction Wind energy has been shown to be one of the most feasible sources of renewable energy. It presents attractive opportunities to a wide range of people, including investors, entrepreneurs, and users. Wind along with other renewable energy sources such as bio and hydro require electromechanical systems to convert naturally available energy sources to rotation through prime movers and then to electricity through electric generators. The prime movers and generators are critical components of such systems that must be affordable, reliable, environmentally safe, and user-friendly. Self-excited induction generators (SEIG) (squirrel cage and/or wound rotor) are strong candidate for such applications. The fact that they are not yet widely used in the field reflects a major gap in knowledge. An attractive option is to take an “off-the-shelve” induction machine and modify it suitably to provide optimized performance in terms of efficiency, suppressed signal distortion and harmonics, resistive losses and overheating, and power factor. In the 1935s, Bassett and Potter [1] demonstrated the possibility of using an induction machine, in the self-excited mode. Since then, the use of induction machines as generators is becoming more popular for the renewable sources [2–5]. The simplicity and flexibility exhibited by the induction machine in providing electromechanical energy conversion make it the favoured choice for wind systems operating with an existing utility grid. Induction generators in general have many advantages: simple, cheap, reliable, brushless (squirrel cage rotor), no synchronizing equipment, absence of DC
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