Study on different loading topologies of a six-phase self excited induction generator

Abstract

High number of phases of a multi-phase machine equip it with greater operational versatility. Due to the presence of dual 3-phases, a six-phase self excited induction generator (6φ-SEIG) is considered very convenient for grid connected as well as off-grid renewable energy based electricity generation systems. Besides, the multi-phase induction generators have been proposed as starter/generator for aero-engines in the aviation industry as more electric aircrafts (MEAs) gain prominence. In this paper six-phase simultaneous loading and three-phase loading at a time of a 6φ-SEIG are investigated. Terminal capacitors provide the reactive power for exciting the SEIG windings. Series capacitances are employed in short shunt connection for self- voltage correction of 6φ-SEIG. A dual d-q mathematical model of short shunt, symmetrical, 6φ-SEIG in dual-stator configuration is developed for the study. All the steady state and transient results are obtained through simulation model. Verification of simulation results is achieved with good accuracy on a prime mover driven open-end stator winding induction machine operated as 6φ-SEIG. For both loading configurations, the full load voltage regulation is maintained within 2% across all phases with optimum excitation and series capacitances of 4 µF/phase and 19 µF respectively. Keywords: Six-phase SEIG, Loading topologies, Short shunt, Dynamic model, Renewable energy