Title :
Analysis of relaxation parameters and their distributions using fractional polarization thermally stimulated discharge currents
Author :
Neagu, R. ; Neagu, E.R.
Author_Institution :
Inf. & Decision Technol., GE Global Res. Center, Niskayuna, NY, USA
fDate :
4/1/2004 12:00:00 AM
Abstract :
It is shown that, in the analysis of fractional polarization thermally stimulated depolarisation current, the values obtained for the activation energy W and the preexponential factor τ0 depend on which one is assumed constant. The elemental peak position and shape change significantly for simulations where we assume that the activation energy is variable and the preexponential factor is constant, or vice-versa. A mathematical expression for the current is proposed in the case where W τ0 and are both variable. The uncertainties affecting the relaxation parameters produce a broadening of the theoretical peak. The minimum uncertainties in the relaxation parameters are estimated. For a current peak at temperature Tm, a calculated distribution of W with width ≈ kTm, or a calculated distribution of τ with width ≈ τ0 is physically meaningless.
Keywords :
dielectric depolarisation; dielectric polarisation; dielectric relaxation; thermally stimulated currents; activation energy; depolarization; fractional polarization; relaxation parameters; thermally stimulated discharge currents; Information analysis; Laboratories; Physics; Polarization; Shape; Statistical analysis; Statistical distributions; Temperature distribution; Thermal factors; Uncertainty;
Journal_Title :
Dielectrics and Electrical Insulation, IEEE Transactions on
DOI :
10.1109/TDEI.2004.1285893