EPRI EXAM PRACTICE QUESTIONS
WITH CORRECT ANSWERS!!
In a 60 HZ system, the frequency of the 8th Harmonic is:
A. 480 HZ
B. 100 HZ
C. 200 HZ
D. 300 HZ
A. 480 HZ
Shunt capacitor tripping can be a problem during GMD activity. Why?
A. Because high frequency GIC currents flow into the shunt capacitors
B. Because GIC currents saturate transformers which creates high
frequency harmonics which cause the shunt capacitors to trip
C. Because GIC currents enter the power system through the
grounded neutrals of the shunt capacitors
D. Because shunt capacitors trip from high ESP
B. Because GIC currents saturate transformers which creates high
frequency harmonics which cause the shunt capacitors to trip
Assume a transmission line has a series inductive reactance of 100 ohms
and a series capacitive reactance of 50 ohms. What amount of series
capacitance (in ohms) must be added to create a series resonance
condition?
A. 100
B. 50
, C. 25
D. 150
B. 50
Which type of HVDC system has two conductors, one energized with a
positive voltage and one with a negative voltage?
A. Semipolar
B. Bipolar
C. Unipolar
D. Monopolar
B. Bipolar
Thyrister and mercury-arc are types of __________ in HVDC converters.
A. Transformers
B. Electrodes
C. Valves
D. Filters
C. Valves
A twelve-pulse converter has twelve pulses in its DC output per:
A. Commutation of the converter
B. Cycle of the HVDC converter from no load to full load
C. Change of the firing angle from 0 to 30 degrees
D. Cycle of the incoming AC voltage
D. Cycle of the incoming AC voltage
An HVDC converter firing angle is used to:
A. Delay inversion
B. Delay commutation
C. Delay conversion
D. Delay rectification
B. Delay commutation
WITH CORRECT ANSWERS!!
In a 60 HZ system, the frequency of the 8th Harmonic is:
A. 480 HZ
B. 100 HZ
C. 200 HZ
D. 300 HZ
A. 480 HZ
Shunt capacitor tripping can be a problem during GMD activity. Why?
A. Because high frequency GIC currents flow into the shunt capacitors
B. Because GIC currents saturate transformers which creates high
frequency harmonics which cause the shunt capacitors to trip
C. Because GIC currents enter the power system through the
grounded neutrals of the shunt capacitors
D. Because shunt capacitors trip from high ESP
B. Because GIC currents saturate transformers which creates high
frequency harmonics which cause the shunt capacitors to trip
Assume a transmission line has a series inductive reactance of 100 ohms
and a series capacitive reactance of 50 ohms. What amount of series
capacitance (in ohms) must be added to create a series resonance
condition?
A. 100
B. 50
, C. 25
D. 150
B. 50
Which type of HVDC system has two conductors, one energized with a
positive voltage and one with a negative voltage?
A. Semipolar
B. Bipolar
C. Unipolar
D. Monopolar
B. Bipolar
Thyrister and mercury-arc are types of __________ in HVDC converters.
A. Transformers
B. Electrodes
C. Valves
D. Filters
C. Valves
A twelve-pulse converter has twelve pulses in its DC output per:
A. Commutation of the converter
B. Cycle of the HVDC converter from no load to full load
C. Change of the firing angle from 0 to 30 degrees
D. Cycle of the incoming AC voltage
D. Cycle of the incoming AC voltage
An HVDC converter firing angle is used to:
A. Delay inversion
B. Delay commutation
C. Delay conversion
D. Delay rectification
B. Delay commutation
