The purpose of this paper is the calculation of Unbalanced Magnetic Force (UMF) in permanent magnet brushless DC (PMBLDC) machines with diametrically asymmetric winding and investigation of UMF variations in the presence of phase advance angle. This paper presents an analytical model of UMF in surface mounted PMBLDC machines that have a fractional ratio of slot number to pole number. This model...

We introduce a parameter called pointing error thermal sensitivity (PETS) for quantitatively determining the quality of a quadrupolar (QAD) fiber coil under radial temperature variations. We show both analytically and experimentally that the pointing error of a fiber gyro incorporating the fiber coil is linearly proportional to the final radial thermal gradient on the coil, with PETS as the pro...

We describe an angularly asymmetric interface-scattering mechanism which allows to spatially separate the electrons in the two low-energy valleys of bilayer graphene. The effect occurs at electrostatically defined interfaces separating regions of different pseudospin polarization, and is associated with the helical winding of the pseudospin vector across the interface, which breaks the reflecti...

Power system overvoltages due to switching, lightning and other disturbances are the main problem for designers of the power transformers. Once some frequencies of the incoming surges match with some of the natural frequencies of transformer winding, the resonance phenomenon is expected in transformer winding. The resonant overvoltages may destroy the insulation between turns and cause to insul...

The early inter-turn short-circuit fault of field winding (ISFF) occurs between adjacent strands in a single rotor slot, which is significant safety hazard the transient operation large-capacity synchronous condenser. To realize high-precision detection ISFF, this paper proposes characteristics analysis method ISFF with strand as minimum unit. This combines novel stator asymmetric branch connec...

Electromagnetic forces in power transformer windings are produced by interaction between the leakage fluxes and current passing them. Since the leakage flux distribution along the windings height is in two axial and radial directions, so the electromagnetic forces have two components, radial and axial. There is a risk that a large electromagnetic force due to the short circuit or inrush current...

Photonic crystal slabs are a versatile and important platform for molding the flow of light. In this thesis, we consider ways to control the emission of light from photonic crystal slab structures, specifically focusing on directional, asymmetric emission, and on emitting light with interesting topological features. First, we develop a general coupled-mode theory formalism to derive bounds on t...

In this Article dispersion characteristic of conventional optical waveguide with helical winding at core – cladding interface has been obtained. The model dispersion characteristics of optical waveguide with helical winding at core-cladding interface have been obtained for five different pitch angles. This paper includes dispersion characteristics of optical waveguide with helical winding, and ...

The wind turbine converts the wind energy into electrical energy, wherein the electrical machines are coupled with wind turbines for this conversion. The electrical machines are liable to meet with faults, but to regain the system reliability the faults should be detected earlier. According to studies of electrical power research institute (EPRI) most of the faults in electrical motors are crea...