Performance Enhancement of Three-Phase SEIG to Feed Single-Phase Load in Micro-hydro Systems Using a Novel Capacitor Excitation Topology

Three-phase self-excited induction generator (SEIG) plays a vital role in micro-hydro systems (MHSs) to generate off-grid single-phase power for hilly terrain-based remote areas. In general, various capacitor excitation topologies (CETs) are available for supplying the requisite reactive power to the three-phase IG while producing single-phase power from the system. Generation of single-phase power from a three-phase SEIG driven by the MHS indicates a worst case of imbalance in the system in terms of phase voltages and stator currents of the generator. This chapter aims to implement a new CET to generate single-phase power from an MHS-driven 2.2 kW three-phase SEIG, whose stator is connected in delta, and the excitation cum reactive power is supplied from a star connected capacitor bank. The proposed CET-IG system is simulated in MATLAB/Simulink and analyzed in steady state for supplying single-phase load under fixed SEIG speed with 55% loading. The result indicates that the recommended CET can effectually supply the single-phase load having voltage regulation of 1.26% and exhibiting a perfect balance in the phase voltages and stator currents of the three-phase SEIG. Hence, in order to generate clean-cum-sustainable power practically in a cheap way for the remote hilly areas from hydro resources at small scale level (i.e., MHS), the proposed CET-IG scheme seems to be an effective one. The recommended CET therefore can be seen to supply the single-phase load in an efficient way, keeping the phase voltages and stator currents of the SEIG balanced while supporting a loading of 55%.