Excitation requirements for stand alone three-phase induction generator

Self excitation in induction machine depends on appropriate combination of speed, load and excitation capacitance. This paper presents direct methods derived from Loop and Nodal analyses to find different criteria for maintaining self excitation. Unlike available techniques, the inverse- model for the steady state equivalent circuit has been used. This is found to be of much assistance in the analysis. Besides determination of speed limits for Axed terminal parameters, and capacitance requirement under varying speed and load, a method to test the possibility of self excitation for known speed, load and terminal capacitance has also been presented.