Search

For the design of superconducting magnets, the magnetic field and critical current distributions are usually calculated based on finite element software such as COMSOL, ANSYS, etc. These software are necessary for accurate structure modeling and field calculation, but they occupy large memory space and comsume long simulation time. Furthermore, they are not easy to use. To achieve an easy-to-implement solution for rapid magnet field and critical current calculations, this paper investigates three types of analytical calculating methods, and builds an autonomously-operated calculating application program (APP) for the uses in various superconducting magnets.

The shortage of dc protection device limits the development of dc grids. This letter proposes a novel superconducting magnetic energy storage (SMES)-based transformerless series voltage restorer (TLSVR) for dc-load protections. The proposed SMES-TLSVR is made up mainly of a bidirectional-switch-based converter and a superconducting coil, and is interfaced in the series with the dc transmission line. It has the advantages of duplex voltage compensation ability, transformerless structure, and swift compensation response, and has a wider compensation range than traditional voltage-fed transformerless dynamic voltage restorer. The topology, circuit principle, and control strategy are elaborated in this letter. Finally, a kW-class SMES prototype is carried out to verify the feasibility of the proposed SMES-TLSVR.

This paper presents the preliminary experiments of a cryogenic boost chopper based on low-resistance MOSFETs and zero-resistance ReBCO inductor under 77K. Three cryogenic operating behaviors of on-state resistances and breakdown voltages of commercial MOSFETs and on-state voltage across their built-in reverse diodes are experimentally investigated to demonstrate the technical feasibility of cryogenic power conversion. Being verified by extremely low conducting resistances under 77 K, two cryogenic power MOSFETs and one ReBCO inductor are subsequently used to develop a cryogenic boost chopper circuit. The experimental results obtained by different circuit schemes and testing conditions show that the overall power conversion efficiency in the cryogenic boost chopper is improved by about 7% than that in conventional boost chopper. These preliminary experiments lay some technical bases for maximizing the operating efficiencies in superconductor-semiconductor-coupled cryogenic power electronic interface towards smart DC microgrids.

mproving energy efficiency is an important way of energy saving and emission reduction. Great achievements have been obtained by the First Long-term Agreements on Energy Efficiency (short for LTA1) of Netherlands in this regard. Whats more, it deserves to learn. The history, structure, operation process, achievements and deficiencies of LTA1 are analyzed systematically, and the enlightenments about how to improve energy efficiency in China will also be provided in this paper.

The role played by cytokines, other than interferon (IFN)-α, in the differentiation and function of dendritic cells (DCs) in systemic lupus erythematosus (SLE), remains unclear. Serum interleukin-10 (IL-10) levels are generally elevated in SLE patients, which might modulate the differentiation of DCs. In this study, DCs were induced from monocytes either by transendothelial trafficking or by culture with granulocyte-macrophage colony-stimulating factor (GM-CSF) + IL-4 + tumor necrosis factor (TNF)-α. Both systems were used to investigate the effects of elevated serum IL-10 level on DC differentiation in SLE patients. The results showed that monocyte-derived DCs induced by either SLE serum or exogenous IL-10 reduced the expression of human leukocyte antigen (HLA)-DR and CD80, decreased IL-12p40 level, and increased IL-10 level, and exhibited an impaired capacity to stimulate allogenic T-cell proliferation. These results indicate that serum IL-10 may be involved in the pathogenesis of SLE by modulating the differentiation and function of DCs.