Eccentricity faults compensation in SRMs by counterbalancing ampere turns in facing poles

In this paper, a new eccentricity compensation method for Switched Reluctance Machines (SRMs) is presented. Eccentricity faults are very common in these machines; nevertheless there are little literatures addressing the control and compensation on this issue. It is theoretically shown that the occurrence and growth of the eccentricity fault change the amplitude of radial forces (RF) exerted on the rotor and accordingly the amplitude of the unbalanced magnetic force (UMF) is increased, these RFs can be controlled to compensate the fault. In this regard, the dependency of RF on variation of number of turns for stator coils and fault level is demonstrated analytically and principle of the new compensation strategy is introduced as well. This strategy is implemented on a SRM utilizing Finite Element Method (FEM). This approach is accomplished through switching among the various arrangements in the number of turns for the coils on the stator poles; hence, UMF is controlled without additional auxiliary coils.