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Corona Discharges

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…

Transformer Substation: The majority of the sub-stations in the power system are concerned with the changing of voltage level of electric supply. These are known as Transformer Substation because transformer…

Substation

Substation: The assembly of apparatus used to change some characteristic (e.g. voltage, ac. to dc., frequency, p.f. etc.) of electric supply is called a Substation. Sub-stations are important part of…

Types of Surge Absorber

Types of Surge Absorber: The travelling waves set up on the transmission lines by the surges may reach the terminals apparatus and cause damage to it. The amount of damage…

Types of Lightning Strikes

Types of Lightning Strikes: There are two Types of Lightning Strikes may strike the power system (e.g. overhead lines, towers, sub-stations etc.), namely; Direct stroke Indirect stroke 1. Direct stroke:…

Voltage Surge or Transient Voltage

Voltage Surge or Transient Voltage: A sudden rise in voltage for a very short duration on the power system is known as a Voltage Surge or Transient Voltage. Transients or…

Distance Protection

Distance Protection: Both time-graded and pilot-wire system are not suitable for the protection of very long high voltage transmission lines. The former gives an unduly long time delay in fault…

Protective Relay

Protective Relay: A Protective Relay is a device that detects the fault and initiates the operation of the circuit breaker to isolate the defective element from the rest of the…