Analytical Design of On load Magnetic Flux Density and Flux-linkage in Radial Flux Air-cored Permanent Magnet Electrical Machine with a Double-sided Rotor

In this article, a radial magnetic flux density and flux-linkage of the radial flux Air-Cored permanent magnet electrical machine (RFAMP) is provided with double-sided rotor which can be calculated analytically using the sub-domain analysis. First, Analytical relationships of on load magnetic flux density and flux-linkage of this machine are presented with poisson equations and, then, these relationships are validated by finite element of numerical results in Maxwell 16.02 software. Comparisons show that the difference between fundamental components of radial magnetic flux density and flux-linkage of analytical relations and that of finite element results is less than 3%. Also, It is shown that in this machine type, even harmonics appear and the radial components of the magnetic flux density is not symmetrical, unit half cycle and Lack of attention to this subject in the design of the machine can cause inner or outer yoke magnetic saturation. In this article, to calculate the flux linkage resulting from the armature reaction, all the components of winding conductor density distribution are utilized and in the calculation of the flux linkage, all radial components of the magnetic flux density are used. In some relevant references, only the first radial component of the magnetic flux density and the second component of winding conductor are used and the other are ignored. In comparison with some related references the linkage flux and RFAPM machine inductance have been increased about 21%, that the number is significant in the study of magnetic saturation yokes. It is worth noting that the study of the comparative results has only been up to 17th harmonics and that the higher harmonics can adapt better to have the finite element results.