A variable-speed constant-frequency self-excited induction generator

The thesis describes the design and development of a stand-alone variable-speed constant-frequency self-excited induction generator, using field-oriented control techniques to provide the necessary voltage and frequency control. Open- and closed-loop models are developed for the generator using tensor techniques and these are subsequently used in the control system design and simulation. For the closed-loop system, both conventional and field-oriented control strategies are developed. A laboratory-scale system was designed and built, to illustrate the system performance. The generator is driven by a separately-excited DC motor to simulate a variable-speed wind turbine and a 2.2kW wound rotor induction machine is used as the generator. The generator excitation current is provided by a current-controlled voltage-source inverter. [Continues.]