Power generation and control of a self excited squirrel cage induction generator

Abstract

The self-excited squirrel cage induction generator (SEIG) is frequently considered as the most economical solution for powering customers isolated from the utility grid by wind energy because it derives its excitation from its own output terminal and neither an exciter nor voltage regulator is required. Its major drawbacks, however, are poor voltage and frequency regulation under variable load conditions. The aim of this paper is to investigate a feedback control strategy that takes a fraction of the output power and applies it to the prime mover as torque. The wind turbine is to be tied mechanically to the rotor of a squirrel cage induction which is fed with grid powerthat the generator supplies. A back to back converter is used to maintain a constant voltage/frequency relationship at the motor terminals. The implication of this model is investigated. The performance characteristics of the machine for various machine variables are also investigatedusing the MATLAB/SIMULINK environment.Keywords: Wind Power systems, Self-excited squirrel cage induction generator, squirrel cage induction motor, backto- back converter, simulation