DESIGN RANGE OF CAPACITANCE FOR SELF-EXCITATION OF A STAND-ALONE INDUCTION GENERATOR

With reference to a derived mathematical model, this paper discusses t he main parameters that influence the process of self excitation of an isolated induction generator feeding a 3-phase balanced load. The par ameters are: the type of load impedance, the value of the load impedan ce, the load power factor, the terminal capacitance and the rotor spee d. Results are presented to demonstrate the inter-relationships of the se parameters. The mathematical model shows that the self-excitation p rocess will be ensured if the load impedance and the corresponding cap acitance have values above a critical minimum. The rotor speed and the load power factor are shown to have a significant influence on the cr itical values of the capacitance required for self excitation.