Indian Journal of Science and Technology

Abstract

Objectives: The present research aims at enhancing the performance of the self-excited wind-driven cheap cage induction generators at the different wind speeds employing control technique involving altering the number of poles of the cage generator and adjusting the shunt capacitor. The control aims to maximize the input power captured from the wind, and to improve the generator electrical performance when the generator feeds static loads, and when supplies dynamic induction motor load. Methods: The analysis of the system has been carried out utilizing a complete mathematical model presented for the driving wind-turbine, in addition to developed mathematical models derived from modernistic circuit models for the self-excited induction generator with both static and dynamic loads. A computer simulation has been performed using the models to identify the performance characteristics. Findings: Control protocols for the generator exciting capacitor and the number of magnetic poles have been reached, which governs the generator speed such that the wind turbine blades revolves at speed which is optimally proportional to the wind stream velocity. Consequently, the highest mechanical power is being taken from the wind. At the same time, the built-up voltage could be adjusted around the load rated voltage for static loads through the newly suggested pole-control technique. In case of dynamic induction motor loads, the poles it is found that good performance is possible through controlling the capacitor size only while fixing the number of magnetic poles at the minimum number. Application: The suggested method leads to cheap and efficient utilization of the wind energy in electrical power generation system, especially in the remote isolated places where usage of systems of selfexcited cage induction generators is highly recommended. 

Keywords: Cage Induction Generator, Pole-amplitude Modulation, Self-excited, Wind Energy