The processes of ion-complex formation (ionic pairs, triplets, dipole-dipole and ion-dipole clusters) and associated conductivity in liquid dielectrics are considered. Experimental method and results on ionization process in solution of transformer ion with iodine are discussed.
H.-P. Schulze, G. Wollenberg, M. Lauter, M. Storr, W. Rehbein
In the paper functional goals of the measurement equipment for the investigation of electrical discharges in dielectric working fluids are discussed. Electrical discharges take place at electrode distances smaller than 200 /spl mu/m. As an example the influence of the viscosity on the ignition behaviour and on typical phases of the spark erosion are analyzed.
Assurance of the quality system of laboratories for transformer physical-chemical diagnostics necessitates the implementation of particular activities so as to provide for an appropriate diagnosis of an observed transformer. Adoption of the quality system assures the constant and adequate quality of most of the laboratory services. The quality system is formally approved after the laboratory has b...... hiện toàn bộ
While the gassing of oil, as determined by periodic dissolved gas analysis (DGA), is attributed to an incipient electrical failure, for the gradual deterioration of paper insulation its aging process is considered to be responsible. These deficiencies, both of which negatively affect the service reliability of high voltage power transformers, are currently perceived as two independent phenomena. I...... hiện toàn bộ
#Power transformers #Aging #Petroleum #Dissolved gas analysis #Dielectrics and electrical insulation #Gas insulation #Oil insulation #Power transformer insulation #Laboratories #Monitoring
We report measurements of electron mobility /spl mu/ in Ar gas in a range below and above the critical point. /spl mu/ is measured as a function of the electric field E for densities up to N < 100 /spl times/ 10/sup 26/ m/sup -3/, encompassing the critical density (N/sub c/ = 80.8 /spl times/ 10/sup 21/ m/sup -3/), for T=142.8, 152.2, 177.3, and 199.7 K The data confirm the model proposed for the ...... hiện toàn bộ
#Electron mobility #Argon #Temperature #Particle scattering #Kinetic theory #Density measurement #Electric variables measurement #Artificial intelligence #Stationary state #Charge carrier processes
For the operation of high temperature superconducting (HTS) devices liquid nitrogen (LN2) is necessary to cool the HTS conductor down to the operating temperature of about 77 K. Depending on the application in electrical power systems and high voltage devices, LN2 is also an attractive dielectric liquid. Some prototypes of cables, power and traction transformers and current limiters were built, bu...... hiện toàn bộ
#Dielectric measurements #Cryogenics #Dielectrics and electrical insulation #High temperature superconductors #Temperature dependence #Superconducting cables #Aging #Superconducting devices #Nitrogen #Conductors
This paper is aimed at the influence of the hydrostatic pressure on the discharge propagating at the liquid/solid insulating interfaces under AC and DC voltages using a point-plane electrode arrangement. It is shown that different shapes of creepage discharges and associated currents can be initiated for the same experimental conditions indicating the existence of different propagation modes of di...... hiện toàn bộ
K. Yoshino, R. Ootake, M. Takeda, A. Fujii, A.F. Ozaki
Upon infiltration of various liquids in opal and its polymer replica photonic crystals with a three-dimensional periodic structure of the order of the optical wavelength, the color changed remarkably and the sharp reflection peak and absorption dip changed drastically with wavelength. These shifts are strongly dependent on the sort of infiltrated liquids and can be explained by the difference of r...... hiện toàn bộ
In the past few years, the liquid rare gas detectors (LRGD) have made a considerable progress and found application in various fields of research, such as high energy experiments, astrophysics, search of rare processes and medical imaging. In this paper, the two best established technologies based on liquid rare gases - electromagnetic calorimeters and time projection chambers - are briefly review...... hiện toàn bộ