A New and Simple Mathematical Technique to Study the Steady-state Performance of Isolated Asynchronous Generator

Abstract

Isolated Asynchronous Generator (IAG) is nowadays widely used for renew-able power generation from the sources like wind and small hydro. Tradi-tionally, the steady-state analysis of IAG is carried out by solving a complexhigher order non-linear polynomial equation obtained in a complicated wayfrom the steady-state circuit diagram. In this paper, a simple new mathe-matical procedure has been introduced to obtain two non-linear polynomialequations in much more simplified form which can easily be solved forthe unknown variables i.e., per unit generated frequency (a) and magnetiz-ing reactance (Xm). Between these two equations, one equation comprisesonly one unknown variable‘a’ and hence, easy to solve. Differential SearchAlgorithm (DSA) has been efficiently implemented for solving these non-linear equations. The computational efficacy of DSA has been compared withthat of Newton-Raphson (N-R) method, Linear Search Algorithm (LSA),Binary Search Algorithm (BSA) and Particle Swarm Optimization (PSO) technique. The performance of the IAG has been studied under differentoperating conditions such as variation of speed, capacitance and load. Allthe simulated results have been experimentally verified using a three-phase,415 volts, 2.2 kW, star-connected induction generator and a close agreementhas been found.