A flux-mnemonic permanent magnet brushless motor for electric vehicles

In this paper, a new permanent magnet (PM) brushless motor is proposed for electric vehicles. The key is to incorporate the concept of memory motors, namely, the online tunable flux-mnemonic PMs, into the stator doubly fed doubly salient PM motor, hence achieving effective air-gap flux control. By further employing the outer-rotor and double-layer-stator topology, the proposed motor takes the definite advantages of compact structure, low armature reaction, and direct-drive capability. Increasingly, this motor can offer the unique features of pole dropping and pole reversing. Finite element analysis and, hence, computer simulation are given to verify the validity of the proposed motor. © 2008 American Institute of Physics.link_to_subscribed_fulltextThe 52nd Annual Conference on Magnetism and Magnetic Materials, Tampa Bay, Florida, 5–9 November 2007. In Journal Of Applied Physics, 2008, v. 103 n. 7, article no. 07F10

Design and control of a new double-stator cup-rotor permanent-magnet machine for wind power generation

In this paper, a new double-stator cup-rotor permanent-magnet machine is proposed and implemented for wind power generation. The design of unique double-stator configuration can improve the power density for easy installation, while the control of its winding connections can provide a constant output voltage over a wide range of wind speeds. The circuit-field-torque coupled time-stepping finite element method is utilized to analyze the proposed machine. Both analysis and experimental results are given to confirm the validity of the proposed machine. © 2007 IEEE.published_or_final_versio

Comparison of stator-permanent-magnet brushless machines

This paper quantitatively compares two emerging stator-permanent-magnet (PM) machines, namely, the doubly salient PM and the PM hybrid brushless types. Both of them are attractive for electric vehicles and wind power generation. For comparison, both machines adopt the outer-rotor 36/24-pole topology and are designed based on the same peripheral dimensions. By using the circuit-field-torque time-stepping finite element analysis (CFT-TS-FEM), both steady-state and transient performances of the two machines are critically compared. © 2008 IEEE.published_or_final_versio

Design of a new outer-rotor permanent magnet hybrid machine for wind power generation

This paper proposes and implements a new 36/24-pole outer-rotor permanent magnet (PM) hybrid machine for directly coupled wind power generation. The key is to design the machine with hybridization of two excitations (PMs and dc field windings) in the double-layer stator so that it can provide effective flux control, hence realizing constant voltage output over wide ranges of speeds and loads. The machine design is illustrated by finite-element analysis and then verified by experimentation. © 2008 IEEE.published_or_final_versio

A new efficient permanent-magnet vernier machine for wind power generation

This paper proposes a new outer-rotor permanent-magnet (PM) vernier machine for direct-drive wind power generation, which can offer low-speed operation to directly capture wind power, and enable high-speed rotating field design to maximize the power density. Compared with its mechanical gear counterpart, the proposed machine can eliminate the mechanical wear and tear as well as gear transmission loss, thus improving the generation reliability and efficiency. The key is to newly introduce the flux-modulation poles which can effectively modulate the high-speed rotating field of the armature windings and the low-speed rotating field of the PM outer rotor. By using the time-stepping finite-element method, the proposed machine can be accurately analyzed. Hence, its performances are quantitatively compared with other PM vernier machines, thus verifying its validity. © 2006 IEEE.published_or_final_versio

Isolation and Characterization of Batatasin III and 3,4’- Dihydroxy-5-methoxybibenzyl: A Pair of Positional Isomers from Sunipia scariosa

Purpose: To isolate and characterize chemical compounds of biological importance from the whole plant of Sunipia scariosa.Methods: The whole plant of Sunipia scariosa was extracted with methanol (MeOH) and chromatographed on silica gel and sephadex LH-20 to afford the pure isolates. High perfomance liquild chromatography (HPLC) was used for further purification of the isolated compounds. Characterization ofthe isolated compounds was achieved by 1H and 13C nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS).Results: Batatasin III (3,3’-dihydroxy-5-methoxybibenzyl) and  3,4’-dihydroxy-5-methoxybibenzyl, a pair of positional isomers, were isolated from the whole plant of Sunipia scariosa. The yields of the two isomers were 60 and 40 %, respectively, from the mixture of two  compounds.Conclusion: Batatasin III and 3,4’-dihydroxy-5-methoxybibenzyl, a pair of positional isomers were successfully isolated from the whole plant of Sunipia scariosa for the first time.Keywords: Sunipia scariosa, Batatasin III, 3,4’-Dihydroxy-5-methoxybibenzyl, Isomer