Fuzzy vector control of isolated induction generator taking the saturation effect into account

Abstract

This paper presents the voltage build up process and terminal voltage control of an isolated wind turbine powered induction generator driven by a variable speed wind turbine using fuzzy logic control (FLC) associated with rotor field oriented vector control. Here three-phase induction generator is excited using a PWM inverter/rectifier connected to a single capacitor on the DC side. Wind powered isolated induction generators have an input, wind, which is not controllable. Unlike a grid connected induction generator, in an isolated induction generator there should be a control system that keeps the DC bus voltage at a constant value when the speed of the rotor is varied. FLC allows a more intuitive approach to design which is due to being based on qualitative relations used in everyday language, and also have certain advantages over other conventional controllers such as the classical PI controller, it have the capability of handling uncertain and noisy signals and do not require the knowledge of a detailed mathematical model of the system. The simulation of the system was done with Matlab/Simulink. During voltage build up the variation of magnetizing inductance is taken into consideration.