## 3 General Discussion
As a result, all the negative behaviors caused by the force, such as rotor vibrations, are also observed in AFSRMs. In this study, a \"double-sided rotor and stator FP-AFSRM\" with the geometric structure of a \"double-stator and single-rotor FP-AFSRM\" and the operating logic of a \"single-stator and single-rotor FP-AFSRM\" was proposed. As a result of the magnetostatic analysis of the proposed model consisting of two stators and a single rotor, it has been observed that both the torque ripple is minimized and the average decreases in the generated force are observed. In addition, this proposed model has two air gaps since it has a twin stator structure. Moreover, one of the stators has a shift angle of \(\alpha\) with respect to the other. However, since the operating principle is based on the \"single-stator and single-rotor FP-AFSRM\", it does not have the disadvantages experienced in models with dual stators, such as reduced inductance leading to the decreased output torque, or the formation of unbalanced axial forces due to angular displacement in dual stators [8; 31]. Although it shares the operating principle of the \"single-stator and single-rotor FP-AFSRM\", the proposed models have minimized the common problem of the torque ripple and improved the forces on the rotor. In addition, the reason for preferring a double stator is that the  
Figure 3: The forces in (a) RFSM and (b) AFSRM structures. winding structure is easy to place, and the cooling problem is simpler than double rotor structures. In traditional AFSRMs, the winding structure is wound as short-pitched on the pole head, as in RFSRMs. When a double rotor structure is preferred in AFSRMs, the placement and cooling of the windings is an important problem. In the proposed model, a fully pitched winding structure is used, which is scattered in the slots. In the case of using a double rotor, the placement and cooling of the fully pitched winding structure will create a more complicated situation. For this reason, a double stator was preferred instead of a double rotor structure. Figure 4 shows the trimetric and frontal general views of the proposed double-sided rotor and stator FP-AFSRM, while Table 1 provides the geometric and nominal parameters of the motor. The left stator is energized as the main stator, and the right stator serves as the auxiliary stator. All the geometric dimensions of both stators are identical. Both stators have a fully pitched winding structure. In summary, except for the phase energization timing, all the geometric features of the two stators are identical. Dimensions are given in Table 1 for one side. There is a shift angle of \(\alpha\) between the two stators of the proposed \"double-sided rotor and stator FP-AFSRM\" shown in Figure 4. Since both motors (left and right) operate separately during the operation process, the equation that determines the displacement angle between the layers in the multi-layer SRMs given in Equation (10) was used to determine the optimum \(\alpha\) angle value [36]. \[\alpha=\frac{360^{0}}{P_{r}N_{phase}N_{layer}} \tag{10}\] \begin{table}
\begin{tabular}{c c} \hline \hline
**Geometric Properties and Nominal Parameters** & **Value** \\ \hline Stator/rotor outer diameter (mm) & 220.00 \\ Stator yoke thickness (mm) & 17.50 \\ Stator teeth axial length (mm) & 50.00 \\ Rotor yoke thickness (mm) & 17.50 \\ Rotor teeth axial length (mm) & 16.50 \\ Air gap length (mm) & 1.0 \\ Stator/rotor pole numbers & 6/4 \\ Number of phases & 3 \\ Rated current (Amps) & 10 \\ Rated power (W) & 2750 \\ Rated speed (rpm) & 1500 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Geometric properties and nominal parameters of double-sided rotor and stator FP-AFSRM. Figure 4: (**a**) Trimetric and (**b**) frontal view of the double-sided rotor and stator FP-AFSRM. In Equation (10) \(P_{r}\) indicates the number of rotor poles, \(N_{phase}\) indicates the number of motor phases, and \(N_{layer}\) indicates the number of layers.