Steady State Analysis of Induction Generator Infinite Bus Systems

Abstract

This paper conducts a fundamental analysis on the induction generator infinite bus system which is a useful representation for a wind energy converter interfaced to a utility through a transmission line. A third order model is used to represent the induction generator and the resultant nonlinear system equations are analysed to derive a condition that guarantees the existence of equilibrium points (or steady state solutions) to the dynamic system. This condition is used to derive three other auxiliary conditions which compute (i) the minimum value of capacitance, (ii) the maximum deliverable power and (iii) the maximum external reactance that can be connected to the machine. The conditions listed above are further studied numerically on three different sets of induction generator data. The impact of capacitive requirements on power factor and terminal voltage is examined. It is shown that terminal voltage regulation has a strong restrictive influence on the maximum transferable power. The analysis and studies presented could be a useful tool for preliminary planning studies involving wind energy converters.