1,721,073 research outputs found
High temperature superconducting transformers
No full textThe paper provides an overview of power applications of High Temperature Superconductivity (HTS) with emphasis on superconducting transformers. Properties of available HTS materials are reviewed and modelling aspects briefly introduced. A conceptual design of a 240MVA HTS grid autotransformer is summarised and principal features discussed. The economics of parallel operation is addressed. Finally, details of a small HTS demonstrator built and tested at Southampton University are provided
Superconducting transformers
No full textThe paper provides an overview of power applications of High Temperature Superconductivity (HTS) with emphasis on superconducting transformers. Properties of available HTS materials are reviewed and modelling aspects briefly introduced. A conceptual design of a 240MVA HTS grid autotransformer is summarised and principal features discussed. finally, details of a small HTS demonstrator built and tested at Southampton University are provided
Multiphysics analysis of a hybrid suspension system for middle-low-speed maglev trains
No full textThe suspension force − a critical factor in the operation of middle-low-speed maglev trains − is provided by electromagnets. However, the eddy current effect produced by the relative motion between electromagnets and the steel track causes a reduction of the suspension force, especially under high speed. A novel type of permanent-electro-magnetic suspension system is proposed to improve performance by considering the variation of material characteristics with temperature. A 3D dynamic finite element model of this hybrid system − accounting for the influence of temperature − has been created to study the variation of magnetic flux distribution, suspension force and guiding force under different operational speeds of the train, in comparison with the electromagnetic version. Verified by simulations, the hybrid system has superior performance offering a powerful suspension force and a reliable guidance force even at high speeds of the train
Peer-Reviewed Compilation: Manuscripts from Compumag 2017 Preface From the Editor-in-Chief
No full text
A constrained topology optimization methodology based on budget constrained min-cut
No full textPurpose: The purpose of this paper is to propose a novel methodology based on budget constrained Min-Cut theorem to solve constrained topology optimization (TO). Design/methodology/approach: This paper establishes a weighted network with budget, which is derived from the sensitivity with respect to the constraint function. The total budget carried by the topology evaluates the extent to which the constraint is satisfied. By finding the Min-Cut under budget constraint in each step, the proposed method is able to solve constrained TO problem. Findings: The results obtained from a magnetic actuator including a yoke, a coil and an armature have demonstrated that the proposed method is effective to solve constrained TO problem. Originality/value: A novel methodology based on budget constrained Min-Cut is proposed to solve constrained TO problem.</p
Trapped mode resonances in metalo-dielectric structures with electric asymmetry
No full textThe excitation of an anti-symmetric trapped mode on a symmetric resonator structure is demonstrated through numerical simulation. The electrical symmetry is broken by using different dielectric substrates leading to trapped modes being excited onto a geometrically symmetric metallic structure. These modes are weakly coupled to free space, therefore their resonant response yields a high quality factor
Analysis and design framework for nonlinear switched reluctance machines
No full textA new computationally efficient paradigm for the design and analysis of switched reluctance machines is proposed. At the heart of the rapid analysis and design methodology is the reduced order computational method based on a flux tube model which has been refined and extended. It is demonstrated how the improved model enables consistent and accurate analysis and design optimization. Instead of an analytical derivation, an automatic generation of cubic splines is introduced to model the magnetic flux. The flux linkage functions obtained from the improved flux tube method indicate that the method offers good accuracy compared to finite element based analysis, but with significantly improved computational efficiency. The approach is applicable to translating and rotating switched reluctance machines of various topologies and therefore enables rapid design search and optimization of novel topologies
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