A transmission line is operating with a voltage phase angle different of 30 degrees between
the sending Vs and the receiving bus Vr. If the receiving end load is suddenly increased, the
voltage phase angle difference will be? - ANSWER The phase angle will increase.
When load is increased phase angle will increase.
A load has a power factor of 0.9 lagging. If the load draws 100 MVA, what is the MW draw? -
ANSWER 90 pf= mw/mva
The high side of a delta-wye connection transformer is connected to a power system with
199 kV L-G high side voltage. What is the voltage across the delta winding of the
transformer? - ANSWER Vl-l= square root of 3 times Vl-g 1.73x191= 345kV
If a transmission line is carrying 400 MW and 300 MVAR what is the MVA? -
ANSWER 3-4-5 triangle 500 MVA
The prime mover is the component of the generator that creates the rotational force. In a
typical coal fired steam generator what component spins the rotor? -
ANSWER Turbine
Reactive reserve response during a disturbance is best obtained from which devise? -
ANSWER Synchronous condensers
For two identically constructed transmission lines where Line A is 150 miles long and line B is
15 miles long, if both lines are lightly loaded? - ANSWER A produces more reactive
power than B.
1
,Lightly loaded transmission lines essentially behave like? - ANSWER Shunt Capacitors
You receive an alarm that indicates low oil pressure on an underground transmission cable.
SCADA shows the pressure is continuing to drop. What is the first step you take to protect
the line? - ANSWER Isolate the line
Computer simulations show that for a 100 MW schedule from Bus A to Bus B, 63% of the
schedule will flow on the scheduled path and the remainder will flow on other parallel
paths. What is the distribution factor for the scheduled path? - ANSWER 63%
Which statement best describes how reactive power MVAR power normally flows? -
ANSWER High Voltage to Low Voltage
Which of the following types of data are BA and RC not required to share with one another?
- ANSWER Generator start up cost
TOP must develop, maintain, and implement formal policies and procedures to provide for
transmission reliability. Which of the following DOES NOT need to be addressed in these
policies and procedures? - ANSWER Planned outages of generation units
A 1000 MVA rated generator that produces 800 MW and 100 MVAR is best described as? -
ANSWER Operating in a lagging mode. Inductive system
Which of the following types of MW load is the most impacted by an intentional frequency
reduction? - ANSWER Motor
Assume there are two 250 mile long transmission lines exporting an excessive amount of
MW from a generation area to a load area. One of the lines suddenly trips and the area
power system collapses within a few seconds. The most likely cause of the collapse? -
ANSWER Angle Instability
2
, The phase voltage in a wye-connected load is 277 V. What is the line to line voltage? -
ANSWER 480 V
A simple power system is composed of three lines connecting generation to load. Each lines
the same impedance, is initially loaded at 200 MW, and has a thermal limit of 400 MW. If
one line trips, what the loading on the shortest remaining line be and will the thermal limit
either remaining line be violated? - ANSWER 300 MW and No
The best prediction of system load is the load forecast tool that uses? -
ANSWER Forecasted Weather
If the phase angel at an open breaker is equal to 1/10 of a cycle, this is the the same angle
as? - ANSWER 1/10 of 360 so 36
A ___________ tool is used to ensure the power system can respond within acceptable
limits of N-1 - ANSWER Contingency Analysis
Which of the following activities would not be included in the procedures for transmission
reliability? - ANSWER Ancillary service pricing
The transmission Operator and BA shall provide documentation that operating personnel
have ______ to implement real time actions to ensure the stable and reliable operation of
the BES. - ANSWER Proper NERC Certification Credential
A utility distribution bus has the following customer loads attached. What is the total
customer MW load and is the total customer load capacitive or inductive? 5 MW 1 MVAR &
3 MW 1 MVAR & 2 MW -2 MVAR & 10 MW 3 MVAR - ANSWER 20 mw and Inductive
How many MVARs does a 230 kV, 50 MVAR capacitor bank provide when the voltage id 207
kV - ANSWER Actual MW/ Rated MW ^2 x Capacitor Rating
3
the sending Vs and the receiving bus Vr. If the receiving end load is suddenly increased, the
voltage phase angle difference will be? - ANSWER The phase angle will increase.
When load is increased phase angle will increase.
A load has a power factor of 0.9 lagging. If the load draws 100 MVA, what is the MW draw? -
ANSWER 90 pf= mw/mva
The high side of a delta-wye connection transformer is connected to a power system with
199 kV L-G high side voltage. What is the voltage across the delta winding of the
transformer? - ANSWER Vl-l= square root of 3 times Vl-g 1.73x191= 345kV
If a transmission line is carrying 400 MW and 300 MVAR what is the MVA? -
ANSWER 3-4-5 triangle 500 MVA
The prime mover is the component of the generator that creates the rotational force. In a
typical coal fired steam generator what component spins the rotor? -
ANSWER Turbine
Reactive reserve response during a disturbance is best obtained from which devise? -
ANSWER Synchronous condensers
For two identically constructed transmission lines where Line A is 150 miles long and line B is
15 miles long, if both lines are lightly loaded? - ANSWER A produces more reactive
power than B.
1
,Lightly loaded transmission lines essentially behave like? - ANSWER Shunt Capacitors
You receive an alarm that indicates low oil pressure on an underground transmission cable.
SCADA shows the pressure is continuing to drop. What is the first step you take to protect
the line? - ANSWER Isolate the line
Computer simulations show that for a 100 MW schedule from Bus A to Bus B, 63% of the
schedule will flow on the scheduled path and the remainder will flow on other parallel
paths. What is the distribution factor for the scheduled path? - ANSWER 63%
Which statement best describes how reactive power MVAR power normally flows? -
ANSWER High Voltage to Low Voltage
Which of the following types of data are BA and RC not required to share with one another?
- ANSWER Generator start up cost
TOP must develop, maintain, and implement formal policies and procedures to provide for
transmission reliability. Which of the following DOES NOT need to be addressed in these
policies and procedures? - ANSWER Planned outages of generation units
A 1000 MVA rated generator that produces 800 MW and 100 MVAR is best described as? -
ANSWER Operating in a lagging mode. Inductive system
Which of the following types of MW load is the most impacted by an intentional frequency
reduction? - ANSWER Motor
Assume there are two 250 mile long transmission lines exporting an excessive amount of
MW from a generation area to a load area. One of the lines suddenly trips and the area
power system collapses within a few seconds. The most likely cause of the collapse? -
ANSWER Angle Instability
2
, The phase voltage in a wye-connected load is 277 V. What is the line to line voltage? -
ANSWER 480 V
A simple power system is composed of three lines connecting generation to load. Each lines
the same impedance, is initially loaded at 200 MW, and has a thermal limit of 400 MW. If
one line trips, what the loading on the shortest remaining line be and will the thermal limit
either remaining line be violated? - ANSWER 300 MW and No
The best prediction of system load is the load forecast tool that uses? -
ANSWER Forecasted Weather
If the phase angel at an open breaker is equal to 1/10 of a cycle, this is the the same angle
as? - ANSWER 1/10 of 360 so 36
A ___________ tool is used to ensure the power system can respond within acceptable
limits of N-1 - ANSWER Contingency Analysis
Which of the following activities would not be included in the procedures for transmission
reliability? - ANSWER Ancillary service pricing
The transmission Operator and BA shall provide documentation that operating personnel
have ______ to implement real time actions to ensure the stable and reliable operation of
the BES. - ANSWER Proper NERC Certification Credential
A utility distribution bus has the following customer loads attached. What is the total
customer MW load and is the total customer load capacitive or inductive? 5 MW 1 MVAR &
3 MW 1 MVAR & 2 MW -2 MVAR & 10 MW 3 MVAR - ANSWER 20 mw and Inductive
How many MVARs does a 230 kV, 50 MVAR capacitor bank provide when the voltage id 207
kV - ANSWER Actual MW/ Rated MW ^2 x Capacitor Rating
3
