Design of a Low-Cost Dual Rotor Field Excited Flux Switching Generator for Wind Turbine Applications

In this paper, a novel low-cost Dual Rotor Field-Excited Flux Switching Generator (DRFEFSG) is proposed for low power rooftop wind turbine applications. The proposed DRFEFSG incorporates inner and outer machines to conceive the dual rotor structure. Due to existence of field excitation in the proposed DRFEFSG, overall machine cost is reduced while it offers excellent flux regulation capabilities. Furthermore, single tooth non-overlapped armature and toroidally-wound field windings are utilized which significantly shorten end-winding and reduce overall copper losses. The proposed DRFEFSG is investigated under variable field excitation and rotor speed. To achieve the desired voltage level, field excitation control is implemented while AC-DC rectification is employed to ensure that the proposed DRFEFSG exhibits desired output regardless of the variation of rotor speed and load currents.