Dynamic Analysis and Control of Output Voltage of a Wind Turbine Driven Isolated Induction Generator

This paper presents the applicability of generalized dynamic modeling of self-excited induction generator (SEIG) using state-space approach for wind energy system and control of output voltage by PWM strategy. A wind turbine is modeled for SEIG to make it applicable for wind energy system. The dynamic performance of SEIG under various wind speeds is investigated under no load, with the load, perturbation of load, and short circuit at stator terminals. Output voltage controls by discrete variations of capacitance value under varying load conditions is also analyzed. During voltage build up process the variation in magnetizing inductance is taken into consideration. For the variable wind speed system, the induction generator output is rectified into DC then interfaced with the load by means of a switched mode DC-AC converter (inverter) which is controlled by sinusoidal pulse width modulation (SPWM) stratergy.The controller aims at keeping constant output voltage and frequency even under wide speed variation. The performance of SEIG system under various conditions as mentioned above are simulated using MATLAB/SIMULINK and the simulation results demonstrate the validity of the proposed system.