Selection of excitation capacitance for three phase self-excited induction generator using graph theory and differential evolution

This paper presents a novel approach to determine the minimum excitation capacitance of a 3-phase self-excited induction generator (SEIG) feeding balanced static resistive and inductive loads. The steady state model equations of SEIG are of higher order non-linear polynomial equations based on per-phase equivalent circuit. The equations are developed using graph theory. These high order non-linear equations are solved by differential evolution (DE) optimization method. Since DE is a metaheuristic algorithm, the results of multiple runs are taken and the statistical variations for minimum excitation shunt capacitive reactance (Xc) and generated frequency (a) are shown. The results are also compared with that of Newton-Raphson method. The proposed approach is demonstrated and analyzed on MATLAB platform.