A Design Method to Minimize Detuning for Double Sided LCC Compensated IPT System Improving Efficiency Versus Air Gap Variation

Inductive power transfer (IPT) technology has garnered considerable attention due to its widespread range of applications. The variation in the air gap can result in variations in the loosely coupled transformer (LCT) parameters, including self-inductance and mutual inductance, due to positional deviations with the ferrite cores on both sides. These variable LCT parameters can damage the resonant tank, ultimately resulting in reduced efficiency. To address this problem, a double-sided LCC-compensated IPT system with a compact decoupled coil is proposed in this paper to improve the system's efficiency with respect to the air gap variation. The key idea is to neutralize the variation in LCT parameters through the use of the self-inductance variation of the decoupled coil so that the detuning degree of the system can be suppressed. Subsequently, the analysis and parametric design process of the system are elaborated. Finally, a 1 kW experimental setup is built to verify the feasibility of the proposed method. Experimental results show that the efficiency of the system proposed in this work varies from 92.63% to 74.81%, as the air gap increases from 30mm to 90mm, wherein the primary and secondary self-inductance and mutual inductance increased by 19.3% and 135.3%, respectively. Compared with the traditional method, the maximum efficiency improvement is up to 8.16%

Experimental observation of non-Abelian earring nodal links in phononic crystals

Nodal lines are symmetry-protected one-dimensional band degeneracies in momentum space, which can appear in numerous topological configurations such as nodal rings, chains, links, and knots. Very recently, non-Abelian topological physics has been proposed in space-time inversion (PT) symmetric systems, and attract widespread attention. One of the most special configurations in non-Abelian system is the earring nodal link, composing of a nodal chain linking with an isolated nodal line, is signature of non-Abelian topology and cannot be elucidated using Abelian topological classifications. However, the earring nodal links have not been yet observed in real system. Here we design the phononic crystals with earring nodal links, and verify its non-Abelian topologicial charge in full-wave simulations. Moreover, we experimentally observed two different kinds of earring nodal links by measuring the band structures for two phononic crystals. Specifically, we found that the order of the nodal chain and line can switch after band inversion but their link cannot be severed. Our work provides experimental evidence for phenomena unique to non-Abelian band topology and our simple acoustic system provides a convenient platform for studying non-Abelian charges.Comment: 14 pages, 3 figure

Analysis of Nutritional Components, Active Components and Polysaccharide Properties of Phellinus igniarius

In order to explore the differences of nutrition, active components and antioxidant activity in the fruiting bodies of different Phellinus igniarius, this study compared the nutritional and active ingredient contents of five species of Phellinus igniarius as well as their antioxidant activity of polysaccharides for the sake of obtaining high quality Phellinus igniarius fruiting bodies. The target Phellinus igniarius was identified by rDNA ITS sequence analysis and the antioxidant activity of its polysaccharide was determined. The properties of polysaccharides were analyzed by ultraviolet spectrum, Fourier transform infrared spectrum and high performance liquid chromatography. The results showed that significant differences in the nutrition, active ingredient content and polysaccharide antioxidant activity of different species were observed. The contents of crude fiber, crude protein, polysaccharide, total phenol, total flavone and total triterpene in S-4 were relatively high, while the contents of crude fat and ash were relatively low. S-4 polysaccharides demonstrated excellent DPPH radical, ABTS+ radical and \begin{document}${\rm{O}}_2^-$\end{document} radical scavenging ability, and the half-inhibitory concentration (IC50) were 35.07, 12.87 and 91.34 μg/mL, respectively. The scavenging ability of S-4 polysaccharides against ABTS+ radical was equivalent to that of ascorbic acid. S-4 was used as the target Phellinus igniarius, and was identified as Sanghuangporus vaninii. Ultraviolet, infrared spectrum and monosaccharide composition analysis showed that S-4 polysaccharides had typical polysaccharide characteristic absorption peak, which was composed of glucose, galactose, fucose, glucuronic acid, ribose and mannose, containing β-glycoside bond and furan ring. The S-4 was relatively rich in nutrients and active ingredients, and its polysaccharides had good antioxidant capacity, which would provide a reference for the screening of excellent Phellinus igniarius fruiting bodies and the development and utilization of polysaccharides