Line current differential (87L) protection schemes face extra challenges compared with other forms of differential protection, in addition to the traditional requirements of sensitivity, speed, and immunity to current transformer saturation. Some of these challenges include data communication, alignment, and security; line charging current; and limited communications bandwidth. To address these...

For flyback coverters, the transformer is the most important factor that determines the performance such as the efficiency, output regulation and EMI. Contrary to the normal transformer, the flyback transformer is inherently an inductor that provides energy storage, coupling and isolation for the flyback converter. In the general transformer, the current flows in both the primary and secondary ...

This paper is devoted to improvements of the low-frequency topological model a three-legged stacked-core transformer. It shown that B-H hysteresis loops employed in transformer and ψ– i curves measured at terminals are quite different shape. A distinction made between modeling moderate deep saturations, separated conditionally by level technical saturation (near 2 Te...

The inrush current is a transient current that results from a sudden change in the exciting voltage across a transformer’s windings. It may cause inadvertent operation of the protective relay system and necessitate strengthening of the transformer’s mechanical structure. Many methods were reported in the literatures for reduction and mitigation of transformer inrush currents. This paper represe...

Inrush current is a very important phenomenon which occurs in transformer during energization at no load. It depends on several factors like magnetizing properties of magnetic material, resistant and inductance of primary winding, supply frequency, switching angle of circuit breaker, applied voltage etc. Objective of this study is to estimate the maximum value of transformer inrush current. Mea...

This original work treats the feasibility study of new type of high voltage power supply with a character six-phase for a magnetron 800 Watts-2450 MHz per phase for industrial microwave generators. The design of this new power supply uses a new sex identical single-phase high voltage transformer with magnetic leakage flux, coupled in star. Each single phase supply a cells which multiples the vo...