PM Stator less contra rotation wind power generator

Abstract

The objective of this paper is to propose an efficient, low cost and rugged design of medium sized gearless permanent magnet stator-less contra-rotation wind power generator (PMSLCRWPG). The earlier models of such medium sized generators, capable of generating less than one megawatt electric power, are facing huge mechanical losses due to wear and tear in the tightly coupled mechanical gear system. Due to this heavy arrangement in its mechanical assembly, the earlier design and its prototype could not function with high efficiency. The proposed design focuses on the performance of the model using the concept of stator-less dual rotor arrangement in the generator. The design was tested at various wind speeds and directions and the performance of the proposed permanent magnet machine has been experimented. The results of this sustainable and renewable model and design were compared with those of the existing models to promote green energy systems in the future. A wind turbine generator comprises a stator disposed between first and second generator rotors. The first generator rotor comprises a first rotor shaft and an inner permanent magnet rotor. The second generator rotor is configured to contra-rotate relative to the first generator rotor, and comprises a second rotor shaft and an outer permanent magnet rotor. Inner and outer annular ferromagnetic cores are anchored respectively to radially inner and outer portions of the stator. First and second inner permanent magnets of opposite polarity are anchored to a radially outer surface of the inner permanent magnet rotor adjacent the inner annular ferromagnetic core across an inner air gap, and first and second outer permanent magnets of opposite polarity are anchored to a radially inner surface of the outer permanent magnet rotor adjacent the outer annular ferromagnetic core across an outer air gap.