Self-excited Three-phase Induction Generator Single-phase Load Run Steady-state Analysis

The relationships among the variables and parameters for the positive sequence equivalent circuit and the negative sequence equivalent circuit are expressed respectively, which is based on the symmetrical component method, and magnetizing reactances with distinct values for two different equivalents due to saturation are also given. By applying Thevenin theorem, the loop impedance of the self-excited three-phase induction generator under single-phase operation is derived. The optimization method is used to solve the equation and is analyzed, which is more stabilized and simpler. The calculated values are in agreement with the experimental value, which verifies the accuracy of the presented method.Terminal voltage building up is the basis of the steady-state operation for the self-excited three-phase induction generator under single-phase load. To establish the given voltages for no-load operation, the optimization method presented by Hooke-Jeeves is used to solve constrained optimization problem, which offers the advantages over those of Newton-Raphson method in stability and flexibility.By combining the symmetrical component method and the optimization method, the external characteristics of self-excited three-phase induction generator under single-phase operation are analyzed, which is simple and universal for programming. Under the values of given self-excited capacitors, rotor speeds and loads, the external characteristics are obtained by calculating the magnetizing reactance and frequency.With the fact that the self-excited three-phase induction generator under single-phase operation is characterized with great voltage fluctuation and poor loading ability, the paper shows why the voltage fluctuates. It presents the shunt-capacitor and series-capacitor compensation method to maintain the constant terminal voltage, which lays the foundation for further research.