Minimization of Torque-Ripple in Switched Reluctance Motors Over Wide Speed Range

Abstract

-Torque pulsation mechanism and highly nonlinear magnetic characterization of switched reluctance motors(SRM) lead to unfavorable torque ripple and limit the variety of applications in industry. In this paper, a modification method proposed for torque ripple minimization of SRM based on conventional torque sharing functions(TSF) to improve maximum speed of torque ripple-free operation considering converter limitations. Due to increasing phase inductance in outgoing phase during the commutation region, reference current tracking can be deteriorated especially when the speed increased. Moreover, phase torque production in incoming phase may not be reached to the reference value near the turn-on angle in which the incremental inductance would be dramatically decreased. Torque error for outgoing phase can cause increasing the resultant motor torque while it would be negative for incoming phase and yields reducing the motor torque. In this paper, a modification method is proposed in which phase torque tracking error for each phase under the commutation added to the other phase so that the resultant torque remained in constant level. This yields to extend constant torque region and reduce peak phase current when the speed increased. Simulation and experimental results for four phase 4 KW, 8/6 SRM validate the effectiveness of the proposed scheme.

Impaired social learning predicts reduced real-life motivation in individuals with depression: A computational fMRI study

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Predicting the affective tone of everyday dreams: A prospective study of state and trait variables

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Impaired Social Learning Predicts Reduced Real-life Motivation in Individuals with Depression: A Computational fMRI Study

“…Before the testing session, potential participants attended a screening visit during which the SCID, as well as an interview about past and current medical conditions, were conducted to ascertain that none of the exclusion criteria were met. Subsequently, eligible subjects completed the following online questionnaires at home: trait subscale of the State and Trait Anxiety Inventory (STAI; Spielberger, Gorsuch, Lushene, Vagg, & Jacobs, 1983), Revised Social Anhedonia Scale (RSAS, Eckblad, Chapman, Chapman, & Mishlove, 1982), Uncertainty Intolerance Scale (UIS, Buhr & Dugas, 2002), and a demographics form.…”