Characteristics of Liquid Dielectrics: Essential Characteristics of Liquid Dielectrics should possess good dielectric properties, excellent heat transfer characteristics and must be chemically stable under the range of conditions under which the…
Corona Discharges: If the electric field is uniform, a gradual increase in voltage across a gap produces a breakdown of the gap in the form of a spark without any…
Equipments in Transformer Substation: The Equipments in Transformer Substation depends upon the type of sub-station, service requirement and the degree of protection desired. However, in general, the Equipments in Transformer…
Protection of Transformers: Transformers are static devices, totally enclosed and generally oil immersed. Therefore, chances of faults occurring on them are very rare. However, the consequences of even a rare…
Protection of Alternators: The generating units, especially the larger ones, are relatively few in number and higher in individual cost than most other equipment's. Therefore, it is desirable and necessary…
Definite Distance Type Impedance Relay: Fig. 21.21 shows the schematic arrangement of a Definite Distance Type Impedance Relay. It consists of a pivoted beam F and two electromagnets energized respectively…
Induction Type Directional Overcurrent Relay: The directional power relay is unsuitable for use as a directional protective relay under short-circuit conditions. When a short-circuit occurs, the system voltage falls to…
Switchgear Components in Circuit Breakers: The following are some important components common to Switchgear Components in Circuit Breakers : Bushings Circuit breaker contacts Instrument transformers Bus-bars and conductors 1. Bushings: When…