Abstract
This paper presents a novel approach to determine geometric shapes of flux modulation poles (FMPs) by using the analytical equations for flux density distribution due to armature windings. The magnetic field by the windings is modulated by the FMPs. Then, the resulting magnetic field produces the torque by interacting with the rotor permanent magnets (PMs). Thus, to improve the output power of the machine, the FMP shape should be optimized in terms of the magnetic flux modulation. To do so, the permeance function which can consider the changes of the geometric parameters for the FMPs is defined using the Fourier series analysis method. Consequently, the working harmonic, which is the spatial harmonic of the air-gap magnetic field due to the windings and creates the torque, is given as the function of the geometric variables. The optimal set of design variables to maximize the working harmonic in the analytical equation is obtained by employing the genetic algorithm. The finite element analysis results show that the proposed method improves the output torque of the surface-mounted permanent magnet vernier (SPMV) machines up to 31%. In addition, the torque ripple can be minimized by regulating the harmonic components of the permeance in the analytical equations.
Highlights
Permanent magnet vernier (PMV) machines have received increasing attention in energy conversion systems such as wind power [1,2], electric propulsion [3,4,5], and robotic servo systems [6], because of their high torque density and high efficiency
This paper presents a novel method to design the flux modulation poles (FMPs) shape of the surface-mounted permanent magnet vernier (SPMV) machine by using analytical equations for the flux density distribution in the air-gap due to the armature windings
The analytical expressions for the winding magneto-motive force (MMF), permeance and flux density distributions in the air-gap are derived by using the Fourier analysis technique
Summary
Permanent magnet vernier (PMV) machines have received increasing attention in energy conversion systems such as wind power [1,2], electric propulsion [3,4,5], and robotic servo systems [6], because of their high torque density and high efficiency. The amplitudes of the permeance harmonics were not defined as the functions of the geometric variables for the FMPs. it is difficult to design the FMP shape, which is to maximize the output torque, by using the analytical equations without the FEA method. Addressing the shortcoming, this paper proposes a novel method to design the FMP shape of the SPMV machine by using the analytical equations to calculate the flux density distribution in the air-gap due to the armature windings. The output torque of the SPMV machine is proportional to the working harmonic of the flux density distribution due to the armature windings It indicates that the optimal set of design variables to maximize the working harmonic and output torque can be found in the analytical equation. The cogging torque and torque ripple can be reduced by regulating the harmonic components of the permeance function, while improving the output torque
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
