The algorithms of the present generation practical differential relays are based on two methods. first method is ratio harmonic content current, and second one length time interval between zero-crossing points called gap-detection method. However, these methods suffer from installation fault current limiters (FCLs) in power system transformer (CT) saturation phenomenon. This paper deals with a ...

In the first part of paper detailed analysis existing current transformer (CT) saturation detection methods with their classification is presented. A new method has been proposed in second paper. Mathematical description given. next section a CT model test scheme To identify reliability against nose and remanent flux density experiments have produced fourth section. Comparative between also Fin...

The decision of digital distance relay is very important for making the protection scheme in the transmission system more reliable. As the current signal is taken from the output of the current transformer, the distortion introduced by the saturation in it affects the performance of the distance relay. In this context proper nonlinear modeling of current transformer is necessary and a suitable ...

The Jiles-Atherton (J-A) based current transformer (CT) core model provides accurate modelling of hysteresis and saturation effects and can effectively represent the remanence flux in CT cores. The disadvantage of the J-A CT is the relevant parameters are not easy to obtain. This paper develops a methodology to estimate the parameters for a J-A CT model from a B-H loop. The B-H loop is relative...

A set of relative permeability relations for simultaneous ow of steam and water in porous media have been derived from experiments conducted under conditions that eliminate most errors associated with saturation and pressure measurements. These relations show that the relative permeability for steam phase in porous media varies linearly with saturation. The liquid phase, however shows a variati...

3D Electrical Impedance Tomography (EIT) is an alternative to the traditional CT scan technique that has been used to measure saturation distribution within a rock core. The primary motivation for investigating EIT is the applicability to high pressure, high temperature geothermal reservoir conditions, which would require a metal core holder, therefore eliminating the use of the CT scan techniq...

PURPOSE Our purpose was to define the optimal protocol for imaging of the orbits after vitreous humor replacement with silicone oil. METHODS Eleven eyes in 10 patients with tractional and/or rhegmatogenous retinal detachment were studied. Five CT scans and 18 high-field (1.5 T) MR images were obtained. Standard T1-weighted, T1-weighted with fat and silicone saturation, fast spin density-weigh...

a total of 150 day old female chickens (ross 308) were randomly allocated to 2 groups with 5 replicate and 15 chicks in each replicate to determine the effects of cold induced ascites on performance, antioxidant status, blood enzyme activities and bone metabolism. the two experimental treatments were: 1) chicks that reared under normal temperature (nt) and 2) chicks that reared under cold tempe...

We develop an experimental technique that uses computed tomography (CT) scanning to provide high-resolution measurements of aperture distribution and in situ saturation along with capillary pressure and relative permeability for the same roughwalled fracture. We apply this technique to an induced fracture in a cylindrical basalt core undergoing water drainage. We find that the sum of the water ...