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In this paper, a modified numerical method for calculating the electrical conditions, namely the charge density, the electric field intensity and the current density, in wire-duct electrostatic precipitators is reported. Variation of mobility for both ions and particles in the space surrounding the energized wires is taken into consideration. This method is based on numerically solving the main set of equations, defining the ionized field with presence of dust particles. The space-chargefree field is calculated using the charge simulation technique. This method is checked against published calculated and measured results, showing good agreement. The present findings are correlated to the physics of electrical corona discharge.

In this investigation, a mathematical model for saturated synchronous machines including the effects of both the crossmagnetizing phenomenon and the saturation factors has been used. The effects of the omission of the cross-magnetizing phenomenon from this model on the transient characteristic curves of a saturated synchronous machine under a three-phase short circuit such as the armature, field and damper winding currents, the flux linkages, the electromagnetic torque and the load angle curves, are shown.

The present work is aimed at calculating the magnetic field around a current-carrying conductor positioned in air at a given height above a two-layer ground. The method is based on the successive imaging technique. A three-phase transmission model was constructed to simulate three-phase transmission line above a two-layer ground. The measured magnetic fields agreed reasonably with those calculated for one- and two-layer ground models. The proposed method of calculation is extended for magnetic field assessment in AC substations. The effect of magnetic ores in the top-layer of the ground on substation magnetic field values is discussed. © 2001 Elsevier Science B.V. All rights reserved.

The present work is aimed at calculating the magnetic field around a current-carrying conductor positioned in air at a given height above a two-layer ground. The method is based on the successive imaging technique. A three-phase transmission model was constructed to simulate three-phase transmission line above a two-layer ground. The measured magnetic fields agreed reasonably with those calculated for one- and two-layer ground models. The proposed method of calculation is extended for magnetic field assessment in AC substations. The effect of magnetic ores in the top-layer of the ground on substation magnetic field values is discussed. © 2001 Elsevier Science B.V. All rights reserved.

The present work is aimed at calculating the magnetic field around a current-carrying conductor positioned in air at a given height above a two-layer ground. The method is based on the successive imaging technique. A three-phase transmission model was constructed to simulate three-phase transmission line above a two-layer ground. The measured magnetic fields agreed reasonably with those calculated for one- and two-layer ground models. The proposed method of calculation is extended for magnetic field assessment in AC substations. The effect of magnetic ores in the top-layer of the ground on substation magnetic field values is discussed. © 2001 Elsevier Science B.V. All rights reserved.

Th e present work aims at developing a meth od-Jar the first time-for assesBing Ow decide jield around a chmyed conduct or posit ioned in air (oJ zero conduc tivity) at a .'liven height above a two-layer earth. The method is based on the com plex su ccessine imaging technique, being a quasi-static approximation fo r estimating the potent ial due to a lin e charge above the eart h. With the knowledge of the image charges , th e electric field uolues in air and earth are (l8ses,"w,d. A luboratoq) trans mission- line model and an electrolytic -t ank model tsere cons tructed to simulate three-phase and single-phase transmission lines above a two-layer earth. The measured electric field s agreed reasonably with those calcula ted fo r one- and two-layer earth models. Th e calculation method is extended for assessing electric fields in power substa tion» as injluenccd by earth modeling in one or two layers.

Th e present work aims at developing a meth od-Jar the first time-for assesBing Ow decide jield around a chmyed conduct or posit ioned in air (oJ zero conduc tivity) at a .'liven height above a two-layer earth. The method is based on the com plex su ccessine imaging technique, being a quasi-static approximation fo r estimating the potent ial due to a lin e charge above the eart h. With the knowledge of the image charges , th e electric field uolues in air and earth are (l8ses,"w,d. A luboratoq) trans mission- line model and an electrolytic -t ank model tsere cons tructed to simulate three-phase and single-phase transmission lines above a two-layer earth. The measured electric field s agreed reasonably with those calcula ted fo r one- and two-layer earth models. Th e calculation method is extended for assessing electric fields in power substa tion» as injluenccd by earth modeling in one or two layers.

This article develops a digital mathematical model in symmetrical components to handle multi-pulse converters power system equipped with correction power factor capacitors or shunt passive harmonic filters. The model simulates AC/DC interaction system in both AC and DC sides with balanced and unbalanced AC system voltages and is adapted for general representation of converter transformers to meet Y/, Y/Y, and Y/Z connections. Comparison results with previous works are given with correction power factor capacitors or shunt passive harmonic filters. The results also included the interaction of AC/DC systems resonating with shunt capacitors at one or more of harmonic power-frequency and the resulting zero sequence harmonics due to AC unbalanced voltage.

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