2020-07-10T06:04:01Z
http://zet10.ipee.pwr.wroc.pl/oai2d/
oai:zet10.pwr.wroc.pl:130
2008-03-22T20:00:14Z
global
eng
Swistacz, B
The effect of generation-recombination processes and of injection mechanism on current-voltage dependences in the metal-dielectric-metal system : I. Carrier generation
http://zet10.ipee.pwr.wroc.pl/record/130/files/
A dielectric model in which electrons and holes are the charge carriers was studied. The space charge is formed by free electrons and holes as well as by trapped electrons. Carrier generation with two trapping states, in steady state and at constant voltage was considered in the assumed dielectric model. The considerations refer to the flat capacitor system. The charge injection mechanisms were described by the function of current density and field intensity at the electrodes. The effect of injection mechanisms in conditions of carrier generation on current-voltage relations was investigated.
2008-03-22T16:52:35Z
oai:zet10.pwr.wroc.pl:131
2008-03-22T20:00:14Z
global
eng
Swistacz, B
The effect of generation-recombination processes and of injection mechanism on current-voltage dependences in the metal-dielectric-metal system : II. Carrier recombination
http://zet10.ipee.pwr.wroc.pl/record/131/files/
A dielectric model in which electrons and holes are the charge carriers was studied. The space charge is formed by free electrons and holes as well as by trapped electrons. Carrier recombination with two trapping states in steady state and at constant voltage was considered in the assumed dielectric model. The considerations refer to the flat capacitor system. The charge injection mechanisms were described by the function of current density and field intensity at the electrodes. The effect of injection mechanisms in conditions of carrier recombination on current-voltage relations was investigated.
2008-03-22T17:00:06Z
oai:zet10.pwr.wroc.pl:132
2008-03-22T20:00:14Z
global
eng
Swistacz, B
Kinetic Model of Carrier Recombination in Solid Dielectric
http://zet10.ipee.pwr.wroc.pl/record/132/files/
In this paper the model of solid dielectric is presented, in which the space-charge is formed by free and trapped electrons, as well as by holes. Charge transport is described by means of the Gauss law, the continuity equation and the system of equations describing the contribution of electron localization and delocalization states in the generation-recombination processes. It is assumed that initial values of carrier concentration are equal to the values of equilibrium concentration Boundary values of free carriers concentration are established basing on mechanisms of carriers injection from metal into the dielectric. The influence of generation-recombination processes and of mechanisms of injection on the time-course of absorption current density are also determined, the latter being evaluated numerically.
2008-03-22T17:05:07Z
oai:zet10.pwr.wroc.pl:133
2008-03-22T20:00:14Z
global
eng
Swistacz, B
Transient states of electric conduction in solid dielectric including carrier recombination : 1. Ideal dielectric without traps
http://zet10.ipee.pwr.wroc.pl/record/133/files/
A model of a dielectric in which the charge carriers are electrons and holes is considered. The flow of charge is described by the Gauss equation, the continuity equation and an equation for the kinetics of carrier recombination. The boundary conditions are determined on the basis of the investigated mechanisms of injections of charge carriers from the electrode into the dielectric. The effect of injection mechanisms, carrier mobility and recombination coefficient on time curves of absorption intensity is investigated. The problem is solved numerically.
2008-03-22T17:09:41Z
oai:zet10.pwr.wroc.pl:134
2008-03-22T20:00:14Z
global
eng
Swistacz, B
Transient states of electric conduction in solid dielectrics including carrier recombination : 2. Ideal dielectric with deep traps.
http://zet10.ipee.pwr.wroc.pl/record/134/files/
Electric conduction in a dielectric with deep traps is analysed. The space charge is made up of free electrons, holes and trapped electrons. The effect of injection mechanisms and carrier mobility on time curves of absorption current density is investigated. The problem is solved numerically.
2008-03-22T17:14:41Z
oai:zet10.pwr.wroc.pl:135
2008-03-22T20:00:14Z
global
eng
Swistacz, B
Bipolar problem of space-charge in dielectric : I. System without trapping.
http://zet10.ipee.pwr.wroc.pl/record/135/files/
A model of a dielectric with bipolar injection of charge in the form of a plane parallel capacitor is presented. Space and time distributions of charge and induction as well as time courses of the resorption current were determined. The resorption state is described by partial differential equations. Initial conditions were determined on the basis of the stationary state of absorption. The theory of partial quasi - linear differential equations was used in the analytical and numerical considerations.
2008-03-22T17:19:01Z
oai:zet10.pwr.wroc.pl:136
2008-03-22T20:00:14Z
global
eng
Swistacz, B
Bipolar problem of space-charge in dielectric : II. System with trapping.
http://zet10.ipee.pwr.wroc.pl/record/136/files/
A model of dielectric with bipolar injection of charge and with trapping taken into account is presented. Charge transport was described by partial differential equations in the system of plane parallel capacitor. The space-time distributions of charge and induction as well as time courses of resorption current were determined. Initial values were found on the basis of stationary state of absorption. In analytical and numerical consideration the theory of partial quasi - linear differential equations was used.
2008-03-22T17:24:49Z
oai:zet10.pwr.wroc.pl:137
2008-03-22T20:00:14Z
global
eng
Leonowicz, Z
Lobos, T
Ruczewski, P
Szymanda, J
Application of higher-order spectra for signal processing in electrical power engineering
http://zet10.ipee.pwr.wroc.pl/record/137/files/
During recent years higher order statistics (HOS) have found a wide applicability in many diverse fields, e.g.: biomedicine, seismic data processing, harmonic retrieval and adaptive filtering. In power spectrum estimation, the signal under consideration is processed in such a way, that the distribution of power among its frequency is estimated and phase relations between the frequency components are suppressed. Higher order statistics known as cumulants, and their associated Fourier transforms, known as polyspectra, reveal not only amplitude information about a signal, but also phase information. If a non-Gaussian signal is received along with additive Gaussian noise, a transformation to higher order cumulant domain eliminates the noise. These are some methods for estimation of signal components, based on HOS. In the paper we apply the MUSIC method (Multiple Signal Classification), both for the correlation and the 4th order cumulant, to investigate the state of asynchronous running of synchronous machines. When the investigated signal is distorted by a coloured noise the exact results can be achieved by applying cumulants.
2008-03-22T17:39:19Z
oai:zet10.pwr.wroc.pl:80
2008-03-22T23:18:47Z
global
eng
Eichhorn, K F
Lobos, T
On-line determination of Symmetrical Components by Sampling
http://zet10.ipee.pwr.wroc.pl/record/80/files/
Symmetrical components of currents and voltages are used for the performance analysis of three-phase power systems (positive-sequence component) and for protection. This paper introduces different algorithms permitting to determine in real time the symmetrical components from few sampled triplets of voltages or currents. By using elaborated algorithms both parasitic harmonics and transients can be suppressed. Finally the attention is given to a general approach to the implementation of a algorithm with a pilot multi-processor equipment.
2008-03-14T20:39:34Z
oai:zet10.pwr.wroc.pl:94
2008-03-22T21:55:37Z
global
eng
Lobos, T
Schneider, E
Eichhorn, K F
Digital Methods for on-line Estimation of the Basic Components of Signals in Electrical Power Systems
http://zet10.ipee.pwr.wroc.pl/record/94/files/
The fast determination of the Symetrical Components of voltages and currents in three-phase systems is very important for the analysis of faults and protection tasks. Digital algorithms for real-time estimation of the positive-sequence component after faults are investigated, using the Fourier- and Kalman filter theory.
2008-03-19T16:44:09Z