A 480-V, 400 kVA, 0.85-PF-Iagging, 50-Hz, four-pole, A-connected generator is driven by a 500-hp diesel engine...

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A 480-V, 400 kVA, 0.85-PF-Iagging, 50-Hz, four-pole, A-connected generator is driven by a 500-hp diesel engine and is used as a standby or emergency generator. This machine can also be paralleled with the normal power supply (a large power system) if desired. a) What are the conditions required for paralleling the emergency generator with the existing power system? What is the generator's rate of shaft rotation after paralleling occurs? b) If the generator is connected to the power system and is initially floating on the line, sketch the resulting magnetic fields and phasor diagram. c) The governor setting on the diesel is now increased. Show both by means of house diagrams and by means of phasor diagrams what happens to the generator. How much reactive power does the generator supply now? d) With the diesel generator now supplying real power to the power system, what happens to the generator as it's field current is increased and decreased? Show this behavior both with phasor diagrams and with house diagrams. A 480-V, 400 kVA, 0.85-PF-Iagging, 50-Hz, four-pole, A-connected generator is driven by a 500-hp diesel engine and is used as a standby or emergency generator. This machine can also be paralleled with the normal power supply (a large power system) if desired. a) What are the conditions required for paralleling the emergency generator with the existing power system? What is the generator's rate of shaft rotation after paralleling occurs? b) If the generator is connected to the power system and is initially floating on the line, sketch the resulting magnetic fields and phasor diagram. c) The governor setting on the diesel is now increased. Show both by means of house diagrams and by means of phasor diagrams what happens to the generator. How much reactive power does the generator supply now? d) With the diesel generator now supplying real power to the power system, what happens to the generator as it's field current is increased and decreased? Show this behavior both with phasor diagrams and with house diagrams.

Answer rating: 100% (QA)

a Conditions for Paralleling Voltage Match The voltage of the emergency generator 480 V must match t... View the full answer