A Novel Three-Phase to Nine-Phase Transformation Using a Special Transformer Connection

Abstract

Multiphase (more than three-phase) electric drive system is the priority of an important research in the last decade. Three-phase supply is available from the grid, however for many industrial applications multiphase supply is necessary. In the multiphase power transmission and multiphase rectifier systems, the number of phases investigated is a multiple of three. This paper proposes a technique to obtain nine-phase output from three-phase supply system using special transformer connections. The primary windings of the transformer connected in star input and secondary side of the transformer connected in star output. The output phases with requisite phase angle of 40 0 between each phase is obtained using appropriate turns ratios. The connection scheme is designed and simulated in MATLAB/Simulink environment. From the simulation results, it is observed that, a pure nine-phase sine-wave of fixed voltage/current and frequency is obtained.