This paper describes the spatial mode, frequencies, the voltage reference update timing, and their interaction of pulsewidth modulation (PWM) harmonics, focusing on a distributed winding permanent ...magnet synchronous motor. We investigated the electromagnetic force generating the noise by using a couple of analyses between a circuit simulator and a two-dimensional finite element analysis. It was found that the electromagnetic noise and vibration result from a radial electromagnetic force spaced at the spatial zeroth mode of <inline-formula><tex-math notation="LaTeX">f_{c}\pm 3f_{1},f_{c}</tex-math></inline-formula>, and <inline-formula><tex-math notation="LaTeX">{{2}}f_{c}</tex-math> </inline-formula> (<inline-formula><tex-math notation="LaTeX">f_{c}</tex-math></inline-formula>: carrier frequency, <inline-formula><tex-math notation="LaTeX">f_{1}</tex-math></inline-formula>: fundamental frequency of the current). We have shown that the radial electromagnetic force of frequency <inline-formula><tex-math notation="LaTeX">f_{c}\pm 3f_{1}</tex-math></inline-formula> and <inline-formula><tex-math notation="LaTeX">{{2}}f_{c}</tex-math> </inline-formula> results from PWM harmonics. Also, the radial electromagnetic force of frequency <inline-formula> <tex-math notation="LaTeX">f_{c}</tex-math></inline-formula> evidently results from the voltage reference update timing of <inline-formula><tex-math notation="LaTeX">{{1/ }}f_{c}</tex-math></inline-formula>. The electromagnetic noise and the spatial mode are demonstrated in the experiment.
Electrification is progressing across different fields such as automobiles and construction machinery. Motors for electric systems are required to be compact and achieve high power density. In this ...study, we developed a small motor with rotation speed of 22,000 r/min by reducing stress concentration. Each pole has three magnets in the circumferential direction, and the magnets are arranged in a U‐shape. The magnet insert slots are comprised of expanded flux barriers on the inner diameter side and a guide‐less structure. The magnet slots reduce stress concentration. Additionally, the rotor has two dents on the outer diameter surface and expanded flux barriers on the outer diameter side. The dents have different shapes between the North (N) and South (S) poles. The structures reduce the torque ripple.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
In this study, a direct drive in-wheel system is proposed as a high power density system for reducing the intermediate parts, such as a speed reducer by increasing the torque. We propose a design ...strategy to show that multipolarization and the improvement of the gap magnetic flux density can effectively increase the power density. A Halbach array magnet rotor that combines the main electrode magnets and spoke magnets with the core is adopted as a technique for improving the gap magnetic flux density. We compare the Halbach array type rotor to the conventional SPM type rotor by using both of magnetic circuit calculation and FEM analysis. Moreover, the actual sized in-wheel motor prototype with the developed Halbach array magnet rotor is fabricated and measures the no-load induced back EMF. The measured no-load induced back EMF agrees well with the analyzed waveform.
Structually related to the known CK2 inhibitors, 2,6‐disubstituted pyrazine and 4,6‐disubstituted pyrimidine derivatives were synthesized and their inhibitory activities toward CK2α and CK2α′ were ...evaluated. Structure‐activity relationship study has revealed that several pyrazine derivatives bearing a (pyrrol‐3‐yl)acetic acid and a monosubstituted aniline possess potent inhibitory activities.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
45.
High Power Density Technology for In-Wheel Motor SUTO, Tetsuya; ITO, Makoto; TAKAHASHI, Akeshi ...
Journal of The Society of Instrument and Control Engineers,
2023/11/10, Volume:
62, Issue:
11
Journal Article
Permanent magnet synchronous motors (PMSMs) are widely used in various applications as high-power-density and highly efficient drive sources. However, a PMSM generates electromagnetic vibration ...because of the space and time harmonics. In this paper, we propose a synchronous PWM control method for shifting the carrier wave phase against the modulated wave. As the proposed control matches the ripple frequencies caused by the spatial and time harmonics, the ripple caused by the space harmonics is canceled by that caused by the time harmonics, with the phase shift of the carrier wave. The phase shift of the carrier wave is confirmed experimentally. In addition, it is experimentally verified that the vibration of the proposed method at a specific frequency is reduced by 46%@7,900r/min and 53%@19,500r/min.
Free fatty acids provide an important energy source as nutrients, and act as signalling molecules in various cellular processes. Several G-protein-coupled receptors have been identified as ...free-fatty-acid receptors important in physiology as well as in several diseases. GPR120 (also known as O3FAR1) functions as a receptor for unsaturated long-chain free fatty acids and has a critical role in various physiological homeostasis mechanisms such as adipogenesis, regulation of appetite and food preference. Here we show that GPR120-deficient mice fed a high-fat diet develop obesity, glucose intolerance and fatty liver with decreased adipocyte differentiation and lipogenesis and enhanced hepatic lipogenesis. Insulin resistance in such mice is associated with reduced insulin signalling and enhanced inflammation in adipose tissue. In human, we show that GPR120 expression in adipose tissue is significantly higher in obese individuals than in lean controls. GPR120 exon sequencing in obese subjects reveals a deleterious non-synonymous mutation (p.R270H) that inhibits GPR120 signalling activity. Furthermore, the p.R270H variant increases the risk of obesity in European populations. Overall, this study demonstrates that the lipid sensor GPR120 has a key role in sensing dietary fat and, therefore, in the control of energy balance in both humans and rodents.
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DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The free fatty acid receptor (FFAR) is a G protein-coupled receptor (GPCR) activated by free fatty acids (FFAs), which play important roles not only as essential nutritional components but also as ...signaling molecules in numerous physiological processes. In the last decade, FFARs have been identified by the GPCR deorphanization strategy derived from the human genome database. To date, several FFARs have been identified and characterized as critical components in various physiological processes. FFARs are categorized according to the chain length of FFA ligands that activate each FFAR; FFA2 and FFA3 are activated by short chain FFAs, GPR84 is activated by medium-chain FFAs, whereas FFA1 and GPR120 are activated by medium- or long-chain FFAs. FFARs appear to act as physiological sensors for food-derived FFAs and digestion products in the gastrointestinal tract. Moreover, they are considered to be involved in the regulation of energy metabolism mediated by the secretion of insulin and incretin hormones and by the regulation of the sympathetic nerve systems, taste preferences, and inflammatory responses related to insulin resistance. Therefore, because FFARs can be considered to play important roles in physiological processes and various pathophysiological processes, FFARs have been targeted in therapeutic strategies for the treatment of metabolic disorders including type 2 diabetes and metabolic syndrome. In this review, we present a summary of recent progress regarding the understanding of their physiological roles in the regulation of energy metabolism and their potential as therapeutic targets.
Zinc (Zn) is one of the essential trace elements required for human developments and it plays an important role in the maintenance of numerous tissue homeostasis. The amount of Zn levels was below ...the constant level which induced the various harmful health effects such as impaired growth, hair loss, taste disturbance, anorexia. Maintenance of Zn homeostasis in body mainly depends on two families of Zn transporters; Zrt- and Irt-like proteins (ZIPs), and Zinc transporters (ZnTs). Some studies based on the gene knock-out mice and human genetic analysis have been reported the relationship between zinc transporters and human diseases. Recent studies have shown that Zn transporter-mediated Zn ion behaves as a signaling factor, called Zn signal, that exerts a multiple function in cellular events. In this review article we describe important physiological roles of Zn transporters and their contribution at the molecular, biochemical, and genetic levels underlying the mechanisms of human diseases.
Clinical isolates of Klebsiella pneumoniae and Klebsiella oxytoca collected from 20 Japanese medical facilities between 2000 and 2010 were analysed to evaluate the mechanisms of resistance and ...antibacterial susceptibilities to 14 antimicrobials. Overall, eight of 484 (1.6%) K. pneumoniae and 19 of 359 (5.3%) K. oxytoca were determined to be extended-spectrum β-lactamase (ESBL) phenotype isolates, and the identified ESBLs amongst the K. pneumoniae isolates were CTX-M-2, -3, -14 and -15, and SHV-12. In contrast, overproduction of chromosomal β-lactamase OXY-2, which was due to a distinct mutation at the - 10 promoter region of this gene, conferred the ESBL phenotype to all the K. oxytoca isolates except one. Based on the Clinical and Laboratory Standards Institute breakpoints, all the ESBL phenotype K. pneumoniae were susceptible to doripenem, flomoxef, moxalactam (latamoxef), cefmetazole and tazobactam/piperacillin, whereas the ESBL phenotype K. oxytoca were susceptible to ceftazidime and ceftibuten in addition to the above, with the exception of tazobactam/piperacillin. Amongst the oral antimicrobials, ceftibuten was relatively effective against both ESBL phenotype Klebsiella species compared with levofloxacin and amoxicillin/clavulanic acid.
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