Synchronous generators are of two type’s salient pole type and round rotor type. The load angle curve of a cylindrical rotor synchronous machine comprises a single sine term only while in salient pole synchronous generators, power-angle characteristic has two terms. The first term is the fundamental component due to field excitation (the same as the cylindrical rotor) and the second term ...

This Letter shows that interleaved sequences of short pulses in the manner of ‘Delays Alternating with Nutation for Tailored Excitation’ (DANTE) with N = 1,2,3 . . . equidistant pulses per rotor period extending over K rotor periods can be used to excite, invert or refocus a large number of spinning sidebands of spin1/2 nuclei in paramagnetic samples where hyperfine couplings lead to very broad...

An in-depth account of the effects of homonuclear couplings and multiple heteronuclear couplings is given for a recently published technique for (1)H--(13)C dipolar correlation in solids under very fast MAS, where the heteronuclear dipolar coupling is recoupled by means of REDOR pi-pulse trains. The method bears similarities to well-known solution-state NMR techniques, which form the framework ...

in this research paper, the performance of an air-cored axial flux permanent magnet synchronous generator is evaluated for low speed, direct drive applications using 3d finite element modeling and experimental tests. the structure of the considered machine consists of double rotor and coreless stator, which results in the absence of core losses, reduction of stator weight and elimination of cog...

air spindles are one of the main elements of precise machine tools. vibration of these spindles is one of the vital issues necessary for investigation. among parameters which influence air spindle vibrations are rotational speed, compression air method, input nozzle diameter, air gap pressure. in this study using ansys, the effects of air gap thickness on air spindle vibrations have been invest...

Flux switching motor is a type of electric machine that locates both flux source and armature windings on the stator leaving its rotor a simple piece of iron. This machine was developed by combining the toothed stator structure of induction machine and the toothed rotor structure of switched reluctance machine together. Furthermore, it has three types of flux sources which include permanent mag...

In the paper, a new low-order parametric force model for an electrical machine with eccentric rotor is developed and verified. The model is designed for an electrical machine equipped with both the parallel stator windings and rotor cage, and, therefore, accounts for the equalising currents in the stator and rotor windings separately and also for their influence on each other. Furthermore, the ...

A technique for amplifying the apparent magnitudes of 13C-1H and 15N-1H dipolar interactions in magic-angle spinning experiments is described. By inserting rotor-synchronized 180 degrees pulses in the evolution period of a 2D dipolar-chemical shift experiment, heteronuclear dipolar couplings are doubled or quadrupled relative to the spinning speed. The increased number of dipolar sidebands is d...

A method based on (1) H high-resolution magic angle spinning NMR has been developed for measuring concentration accurately in heterogeneous materials like that of ligands in chromatography media. Ligand concentration is obtained by relating the peak integrals for a butyl ligand in the spectrum of a water-saturated chromatography medium to the integral of the added internal reference. The method...