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This paper proposes a novel electromagnetic modelling method, with experimental study of the magnetic can-shield effect, based on a novel canned switched reluctance machine. Such model considers the characteristic electromagnetic coupling relation between magnetic flux and eddy current on cans, with harmonic analysis by analytical calculation in vector form. The model is structured with multiple concentrated layers in cylindrical coordinate and the main modeling process includes domain solution of the magnetic field, and an energy vector deduction for loss and energy. Comparative measurement with an indirect method demonstrates the electromagnetic features by the use of cans and meanwhile verifies the analytical model. [ABSTRACT FROM AUTHOR]

This paper introduces an optimal control model strategy to minimize system loss and meantime to maintain low torque ripple for a can-shielded switched reluctance machine (SRM). The system loss consists of semiconductor loss from power converter, as well as loss from the machine which not only includes traditional iron and copper losses, but also the characteristic ohmic can loss and friction loss due to the use of can shields. In particular, the can loss is calculated by Poynting’s theorem of magnetic energy conversion using a model of concentric layer structure. Loss of semiconductors considers temperature rise effect by an electro-thermal coupling approach. The effectiveness is verified on a 3-phase 20 kW 12/8 canned SRM. [ABSTRACT FROM AUTHOR]

In this paper, a novel magnetic circuit network model is proposed for flux calculation on switched reluctance machines (SRM) of double saliency. Specifically, the airgap reluctance is modeled by a topology of paralleled magnetic paths that only depends on geometry and rotor position, while magnetic saturation on poles is modeled by a simple lookup approach. Such network is featured by allowing magnetic coupling effect from multiple phases. The flux linkage and torque generation considering the coupling can be calculated in a fast and accurate way without limit of power density or rotating speed. [ABSTRACT FROM AUTHOR]

Transient simulations of models are required for the study of several phenomena and calculation of some physical quantities. For instance, in the case of a switched reluctance machine (SRM), conducting transient simulations allows the calculation of electromagnetic torque ripple. This can be very time consuming, especially when using an iterative optimization algorithm to smooth the developed electromagnetic torque. In this paper, Output Space Mapping Proportional (OSMP) and Manifold Mapping (MM) are presented as a solution to accomplish a fast determination of the optimal control parameters of a SRM in order to improve its performance. A description of the considered optimization problem is also provided, along with a detailed presentation of the coarse and fine models used. Finally, optimization results are presented, analyzed and validated using finite element-based model as well as measurements on the SRM prototype. [ABSTRACT FROM AUTHOR]

In this paper, power losses in high-speed switched reluctance machine (HS-SRM) is studied considering the copper loss, including skin and proximity effect, iron loss in machine side; switching and conduction losses in the drive circuit side using interactive coupled simulation methods. In high frequency fed electric machines, copper losses are increased due to the skin and proximity effects. Moreover, iron losses play a significant role in total electrical losses. Nevertheless, its computation is not straight. In addition, power electronics switching devices cause both conduction and switching losses in the SRM drive circuit. Switching loss may reach excessive levels with the high-frequency switching. In this study, the losses are calculated detailed though coupled simulation method. Different wire constructions in the bundle are analyzed and compared. Finally, circuit simulation is performed on different switching devices. The results prove that high-speed switched reluctance machine driving and operating efficiency is really sensible to design methodology with suitable material and device selection. [ABSTRACT FROM AUTHOR]

In this paper, a simple magnetic circuit network model is proposed to simulate saliency and can-shield effect with high magnetic saturation for a double salient canned switched reluctance machine. The saliency effect, including rotor position dependent airgap paths and magnetic saturation on poles, is described by discretized and adaptable magnetic reluctance elements. Further, can-shield impact due to electromagnetic coupling in airgap is described by Faraday law of energy conversion. Such a network is featured by adopting characteristic magnetic paths without empirical equations and is applicable to various machine geometries without power density limit. [ABSTRACT FROM AUTHOR]

In this paper, a novel analytical magnetic circuit network model is proposed to simulate saliency effect with high magnetic saturation for electrical machines. Such a network is featured by dividing magnetic paths according to airgap flux distribution characteristics. Magnetic saturation on salient poles is modeled with discretized and in size adaptable reluctance elements. The method uses basic magnetic circuit principles without empirical estimation. The method can be applied without power or speed limit to various machine geometries featured by prominent saliency structure. [ABSTRACT FROM AUTHOR]

Multiphysical optimization design of electrical machines is essential, in which the submodels, including electromagnetic, thermal and noise/vibration (NV) simulation models are required not only to be accurate to facilitate coupling analysis, but also of small computation to guarantee calculation speed. In this paper, a multiphysics design flow for salient electrical machines is proposed. The flow aims to maximize torque with temperature rise and acoustic guaranteed, in which each submodel of fast and accurate calculation is respectively studied. For electromagnetic analysis, an efficient finite element (FE) based program is proposed to model distribution of magnetic saturation on salient poles. For NV analysis, an analytical frequency estimation approach is proposed. For thermal analysis, a lumped parameter network model with compensation elements is studied. An 8/6 salient switched reluctance machine (SRM) of high power density for vehicular traction application is studied. [ABSTRACT FROM AUTHOR]

This paper presents the least square support vector machine (LS-SVM) network as a new tool to develop the model of the switched reluctance machine (SRM) and predict the dynamic performances of SRM system. The basic premise of LS-SVM regression is that it forms a very efficient mapping structure for the nonlinear SRM. By using the measured sample data of SRM, the LS-SVM is designed to learn the nonliear magnetization data with rotor position and phase current as input, and the corresponding flux linkage and torque as output. It has a good capability of generalization and is computationally efficient. With the developed modeling method, a LS-SVM current-dependent inverse flux linkage model and a LS-SVM torque model are used to simulate the dynamic performances of a 6/4 SRM operating as a starter/generator, and the accuracy of the model is tested via comparison to the measurements of steady state phase current characteristics. [ABSTRACT FROM AUTHOR]