14-06-2012, 12:54 PM
Generator Protection Setting Criteria
Generator Protection Setting Criteria.pdf (Size: 3.07 MB / Downloads: 144)
Preliminary
• Faults in power systems occur due to a high number of reasons
such us:
– Lightning
– Aging of insulation
– Equipment failure
– Animal presence
– Rough environmental conditions
– Branch fall
– Improper design, maintenance or operation
• The occurrence of faults is not the responsibility of poor protection
systems. Protective devices are essential in Power Systems to
detect fault conditions, clear them and restore the healthy portion of
the systems.
• Protection relays sense any change in the signal which they are
receiving, which could be of electrical or mechanical nature.
• Typical electrical protection relays include those that monitor
parameters such as voltage, current, impedance, frequency,
power, power direction or a ratio of any of the above.
• Typical mechanical protection relays include those that monitor
parameters such as speed, temperature, pressure and flow
among others.
Protection requirements
• Reliability: ability to operate correctly. It has two components:
• Dependability
• Security
• Speed: Minimum operating time clear a fault
• Selectivity: maintaining continuity of supply
Reverse Power