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 ...

We conjecture chronology is protected in string theory due to the condensation of light winding strings near closed null curves. This condensation triggers a Hagedorn phase transition, whose end-point target space geometry should be chronological. Contrary to conventional arguments, chronology is protected by an infrared effect. We support this conjecture by studying strings in the O-plane orbi...

This paper presents a real-time phase-domain synchronous machine model for generator protection relay testing and its real-time implementation. The model allows full protection scheme validation including split-phase differential and statorground fault protections. Space harmonics are considered through the use of modified winding function theory, which is used to represent arbitrary winding di...

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...

Partial discharges (PD) are recognized as the main cause of the inner insulation deterioration process in power transformers. Therefore, the optimum inner insulation design is one of the challenges a transformer designer is faced with. Transformer strength, especially during transient conditions, is a criterion for transformer insulation designers. This challenge has made designers initiate and...

Transient overvoltages appearing at line terminal of power transformer HV windings can cause failure of winding insulation. The failure can be from winding to ground or between turns or sections of winding. In most of the cases, failure from winding to ground can be detected by changes in the wave shape of surge voltage appearing at line terminal. However, detection of insulation failure betwee...

With changing the parameters of layer winding in transformers, capacitive characteristic coefficient of winding will be changed. Since, impulse voltage distribution (IVD) along a winding is depended on this coefficient, so analyzing this coefficient is important in transformers. This paper study and analyze a transformer with layer winding and rectangular cross-section. In this study, the influ...

The paper deals with modeling of synchronous reluctance motor (SynRM) accounting for all phenomena responsible for torque ripple. Based on winding function approach, the proposed model consists in computing self and mutual inductances considering no sinusoidal distribution of stator windings, slotting effect and no sinusoidal reluctance variation caused by the rotor saliency. Then, optimal curr...

Copper and aluminium are the two conductors most commonly used in transformer windings. This study presents a comprehensive comparison of distribution transformers built either with copper or with aluminium windings. The comparison is based on winding material conductivity, density, cost, connectivity, oxidation, machinability and behaviour under short-circuit. Additionally, a parametric analys...