Unbalanced switching effects on dynamic performance of an isolated three-phase self-excited generator

This paper presents dynamic performance of an isolated three-phase self-excited reluctance generator (SERG) under sudden disconnection of single-phase loads and excitation capacitors. A novel approach based on three-phase reluctance machine model is employed to derive dynamic equations of a stand-alone SERG under different unbalanced conditions. Experimental results obtained from a laboratory 0.37 kW reluctance machine driven by a DC motor are also performed and compared with the simulated results to validate the effectiveness of the proposed method. It can be concluded from the analyzed results that the stator current unbalanced factor for the loaded SERG under switching off one excitation capacitor is much larger than the one under switching off one or two resistive loads. The voltage unbalanced factors for the loaded SERG under switching off one excitation capacitor or switching off one or two resistive loads are very similar. Moreover, the terminal voltage of a loaded SERG cannot be generated when two excitation capacitors are simultaneously switched off.