Simplified methods for the analysis of self-excited induction generators

In this study, two simple methods for the steady-state analysis of self-excited induction generators (SEIGs) are proposed. These methods neither require lengthy mathematical derivations nor any advanced optimisation techniques to solve the equivalent circuit of SEIGs. First method involves a simple linear search algorithm and the second method employs a binary search algorithm to find the operating frequency at any given rotor speed, leading to the performance predetermination of SEIGs. To start the search techniques, a systematic approach has been formulated for fixing the boundary values required for the unknown pu frequency. The efficacy of the proposed methods has been demonstrated by presenting the predetermined performance characteristics of a three-phase, 230 V, four-pole, 50 Hz SEIG. The same SEIG was also tested in the laboratory using a DC motor as the prime mover. The closeness observed between the predetermined values and the experimental results further confirms the validity of the search algorithms. It has also been shown that the proposed methods can be extended with the same simplicity, for carrying out the performance predetermination of the short-shunt configuration of SEIGs, used for obtaining improved voltage regulation with lagging power factor loads.