Search

This paper describes a maximum power point tracking (MPPT) control method for propeller-type compact wind power generators with passive self-pitch-controlled blades, which quickly makes the output current and voltage converge on the maximum power point based on wind speeds detected from an anemometer. The voltage and current output from these wind power generators vary with wind speeds at locations such as the roofs of buildings. Transient characteristics of the voltage output from compact wind power generators have two modes because of the self-pitch-controlled blades: mode I in which the output voltage hardly increases and mode II in which it rapidly increases. Thus, in order to acquire the generated power effectively, irrespective of how the wind speeds may change, a method to perform the MPPT control while searching for mode II is needed. Thus, by judging the mode from the change of the sign of the time differential of the voltage deviation between sampling times, the MPPT control method proposed here makes the output current converge on the maximum point using relationships between the maximum power and optimal current which give the maximum power and the wind speed. Effectiveness of the proposed MPPT control method is verified through simulations and experiments using a wind tunnel. IEEJ Trans 2010 DOI: 10.1002/tee.20609

The methylation of the lithium dienolate generated from (E)-α,β-olefinic amide with Katsuki’s chiral auxiliary affords the α-methylated β,γ-enamide in an exceptionally high Z-selectivity (99%) over the terminal olefinic bond along with 99% de at the α-chiral center. The origin of the high Z-selectivity is discussed.

Enantiomerically pure phosphinamides containing a pendant hydroxyl group catalyse the Al(III)-promoted ring opening of the meso epoxide in cyclohexene oxide with thiophenol in up to 80% enantiomeric excess.

We have developed light-diffusive UV-curable resins with well-controlled scattering properties by adjusting the diameter of the micro particles and the differential refractive index between UV-curable resin matrix and the micro particles. We expect that optical-patterned films for a slim backlight system can be obtained using them by a roll-to-roll continuous process.

We have developed an ultra slim backlight system using optical-patterned film (OPF backlight), which has a lot of advantages to be composed of a single component and less than 0.4 mm in total thickness. Moreover, we have obtained the possibility to manufacture the sheet of OPF backlights by roll-to-roll continuous process.