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...

<span lang="EN-US">Single-phase induction (asynchronous) motors are widely used at home. These have two windings and usually operate a lower performance than 3-phase asynchronous which three windings. For this reason, study aims to design new winding of single-phase motor by increasing the number phases in order increase motor. This research was focused on 36 slot capacitor-start capacito...

In response to the structural optimization problem of PCB stator coreless disc motors, orthogonal surface method was used optimize motor structure, preliminarily determine basic parameters motor, and conduct experiments on based design objectives. The factors were quantity magnetic pole rotor p, ratio main/auxiliary sizes Rnd, thickness Tm permanent magnet, air gap length δ. torque Td, amplitud...

The purpose of this paper is to present a new hybrid analytical model (HAM) based on winding function theory (WFT) for electromagnetic analysis performance one typical unbalanced two-phase induction motor (UTPIM). Different indexes modeling such as distribution, slotting effect, and magnetic saturation can be accurately considered by using the proposed HAM. For obtaining technique, reformulated...

The Pulse Width Modulation (PWM) power electronics systems often produce objectionable acoustic noise at the PWM switching frequency. For example, in a fan / blower drive, the drive used for the blower should use “spread spectrum PWM” technology (also known as Random PWM) where acoustic noise radiating through the duckwork is a very seriously concerned. This paper shows the theoretical basis fo...

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...

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...

This paper presents the analysis of a new multi-oscillated current resonant type DC-DC converter. Current resonant converters have several remarkable features such as high efficiency, small size, low cost and low noise, and are frequently employed in many portable electronic systems such as personal computers, cellular phones and flat panel displays. The current resonant type converter generall...