Abstract

Self - Excitation is a common attribute of Induction generators, whenever capacitors are being arrange in such a way that they are in series with the terminals of the stator, and externally driven by the prime mover. Self – excited generators are often associated with the attendant problem of Poor voltage regulation as well as overload strength which suffers from problems of excitation losses, short-circuit and re-excitation. This can be easily experienced when the generator is used in wind power generation. In situations where carried loads experiences short circuit, excitation is being sustain by the machine but the voltage drops as the fault is sustained. These short comings of the associated with the induction generators with self- excitations (SEIG) are investigated and performance at transient level of a self-excited induction generator under fault conditions is analyzed. The SEIG model equations are first developed and simulation carried out using MATLAB/SIMULINK on the models under different operating conditions. The effect of faults conditions of such a machine is determined through its transient evaluation. From which it could be observed that excitation is lost due to short-circuit experienced at the machine terminals, the machine rebuilt voltage is removed at fault condition and momentarily, the buildup process is faster. Transient quick response of the induction generator under self-excitation makes it most suitable for a self-regulated, rugged and simple generating system.