Analytical modeling of pulsating torque in concentrated-wound interior permanent magnet machines to achieve maximum average torque under an open-phase fault condition

摘要

Fractional-slot concentrated-wound interior permanent magnet machines exhibit a reduction in the average torque and significant torque ripple under an open-phase fault condition. This arises from the spatial harmonics generated in the stator magneto-motive force due to occurrence of the fault. With the purpose of increasing the average torque, a detailed analytical model is proposed for the magneto-motive force and electromagnetic torque of the machine operating under an open-phase fault condition. The proposed analytical model enables determination of optimal current angles to guarantee a maximum average torque with respect to the current amplitude under the open phase fault condition. Finite element analysis of a fractional-slot concentrated-wound interior permanent magnet machine is used to verify the authenticity of the proposed models and approach.