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A wide range of topics related to power system operations and reliability, including tie line readings, generator output, frequency indications, transformer load, contingency reserve requirements, balancing authority responsibilities, system restoration, voltage and frequency control, transmission line overloads, and emergency operating procedures. Detailed information and scenarios that could be useful for students studying power systems, electrical engineering, or energy management. It covers topics such as load shedding, reactive power management, system protection, and real-time grid operations, which are crucial for understanding the complexities of modern power grids and ensuring reliable electricity supply. The document could be particularly valuable for university students pursuing degrees in electrical engineering, power systems, or energy-related fields, as it offers insights into the practical challenges and decision-making processes involved in power system operations.
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The Reliability Coordinator just informed you of a slow time error correction which will begin at the top of the next hour. Your EMS system will not let you change your scheduled frequency. Your Frequency Bias Setting is -100 MW/.1Hz. What action should you take?
A) Increase Net Interchange Schedule by 20 MWs.
B) Inform the Reliability Coordinator that you cannot participate in the time error correction.
C) Decrease Net Interchange Schedule by 20 MWs.
D) Increase Net Interchange Schedule by 10 MWs.
A) Increase Net Interchange Schedule by 20 MWs.
A Balancing Authority has a sudden loss of a large block of load in its area. This loss will be seen instantaneously in the change of which of the following values?
A) 4 only
B) 1 & 3
C) 1 & 4
D) 3 & 4
C) 1 & 4
Metered Data included in the calculation of ACE are: dynamic schedules, pseudo ties, actual frequency, and all __________.
A) Tie lines readings
B) Generators output
C) Scheduled frequency indications
D) Transformer load
A) Tie lines readings
Balancing Authority A is currently reading a system frequency of 60.00 Hz. Its Net Actual Interchange is +100 MW and its Net Scheduled Interchange is +200 MW. If Balancing Authority A's frequency bias setting is 100 MW/0.1 Hz, what is ACE?
If the frequency bias setting is set to a less negative value than the frequency response of a Balancing Authority and a frequency increase is caused by a sudden loss of load in an external balancing area, what will be the result?
A) The ACE will be zero and will take no AGC action
B) The ACE will be a negative value and AGC will increase generation
C) The ACE will be a positive value and AGC will lower generation
D)This will not affect the ACE
B) The ACE will be a negative value and AGC will increase generation
If the frequency bias setting is less negative than the frequency response of a Balancing Authority and a frequency decline is caused by a sudden loss of generation in an external balancing area, what will be the result?
A) The ACE will be a negative value and AGC will increase generation.
B) This will not affect the ACE.
C) The ACE will be a positive value and AGC will lower generation.
D) The ACE will be zero and will take no AGC action.
C) The ACE will be a positive value and AGC will lower generation.
It is the responsibility of which entity/entities to develop, maintain, and implement load shedding plans?
A) Transmission Operators and Balancing Authorities
B) Reliability Coordinator
C) Load Serving Entities
D) Balancing Authority
A) Transmission Operators and Balancing Authorities
A Transmission line is loaded 25% above its SOL. A parallel line is out for routine maintenance and can be placed in service in 10 minutes. What is the first step the Operator should take to reduce the line loading?
A)Shed load at the downstream bus.
B) Open the line.
C) Re-Dispatch Generation.
Under Frequency Load Shedding (UFLS) is to stabilize the imbalance between generation and load that has been created by a system disturbance. This is accomplished by ____________.
A) Tripping generation first
B) Voltage reduction on the distribution system.
C) Shedding all load to arrest frequency
D) Shedding load prior to generation tripping
D) Shedding load prior to generation tripping
Failure to meet the DCS criteria of recovery within 15 minutes results in which consequence for a specified time period for the Balancing Authority's failure to recover?
A) Increased Contingency Reserve requirements
B) Decertification as a Balancing Authority
C) Not allowed to supply regulation services
D) Expulsion from the Reserve Sharing Group
A) Increased Contingency Reserve requirements
A Balancing Authority foresees or is experiencing conditions where all available resources are committed to meet firm load, and firm transactions. The BA should request which level of the Energy Emergency Alerts?
A) Energy Emergency Alert Level 2
B) Energy Emergency Alert Level 4
C) Energy Emergency Alert Level 1
D) Energy Emergency Alert Level 3
C) Energy Emergency Alert Level 1
Preparations are being made to tie two islands together during restoration. Island "A" has a frequency of 58.95 Hz and Island "B" has a frequency of 59.97 Hz. What action should be taken to synchronize the two islands?
A) Shed load in Island "B"
B) Shed load in Island "A".
C) Disable the Synch Check Relay.
D) Increase generation in Island "B".
B) Shed load in Island "A".
You experience a full system shutdown. You are in the process of restoring load and you are concerned about re-collapsing the system. Which is the best approach in the restoration process that will help ensure your system will be restored successfully?
A) Maintain frequency between 59.5 HZ and 60.5 HZ.
B) load should not be shed during the process
C) generators should trip after the UFLS
D) breakers should open at the same time as the UFLS
C) generators should trip after the UFLS
One of the functions of under frequency load shedding is to _________________ within an electrical island that may have been created by a system disturbance.
A) balance generation and load
B) establish balance between load and interchange
C) stabilize balance between generators
D) stabilize the Interconnection
A) balance generation and load
A major transmission line has become overloaded and the transmission operator has taken actions to unload the line. However, the overload persists, and the equipment is now in imminent danger of damage. What is the next action to take?
A) Separate from the Interconnection
B) Disconnect the overloaded line and notify the RC and affected Transmission Operators.
C) Request a Transmission loading relief procedure
D) Request permission from the RC to open the line.
B) Disconnect the overloaded line and notify the RC and affected Transmission Operators.
A report shall be submitted to NERC following the shedding of at least how much firm load?
The System Operator experiences a major transmission system disturbance which results in a large loss of load. Which of the following results is most likely to occur?
A) a decrease in system voltage
B) a decrease in system frequency
C) an increase in system frequency
D) an increase in system voltage in a wide-area
C) an increase in system frequency
Each Transmission Operator is required to have a system restoration plan. What is the first thing a Transmission Operator must do when energizing a blacked out area?
A) Isolate the load.
B) Turn all voltage regulators to the manual position.
C) Contact the Regional Reliability Organization.
D)Close any capacitor banks which are open.
A) Isolate the load.
After declaring an NERC EEA Level 3, load goes higher than your generation resources, what is an effective tool in restoring generation to load balance?
A) Firm Load Shed
B) Exceeding emergency limits
C) TLR
D) Voltage Reduction
A) Firm Load Shed
An 800 MW generator trips in a Balancing Authority external to your Balancing Authority Area. Which of the following indications would you expect to see in your area?
A) Net Actual Interchange would decrease significantly.
B) ACE would drop to approximately -800 MW.
C) Frequency would drop, and ACE would remain relatively unchanged.
D) Frequency would drop, and ACE would increase significantly.
C) Frequency would drop, and ACE would remain relatively unchanged.
When is the only time voltage reduction for load relief is acceptable on the transmission system?
A) When voltage on the distribution system is already low.
B) It is acceptable anytime load relief is needed.
C) When the system is separated from the Interconnection.
D) When Interconnection frequency is above 60.00 Hz.
C) When the system is separated from the Interconnection.
required. When the system voltage returns to .9 p.u. or 90% manual load disconnection is not required.
If a generator trips off line within the BA and the nearby 230 kV system voltage immediately drops to 200 kV and remains at that level for the next 3 minutes. What is the BA required to do?
A) Wait 7 minutes for the remaining generator AVRs to respond; close capacitor banks; adjust Transformer Taps.
B) Immediately disconnect firm system load until the voltage returns to at least. p.u. Notify the RC of the amount of load disconnected.
C) Immediately take actions to raise the voltage EXCEPT removing firm system load. Notify the RC and neighboring BA's. Prepare for manual load reduction if the voltage remains below .9 p.u. over the next 7 minutes.
D) Notify the RC to help support voltage and await instructions to remove firm system load.
C) Immediately take actions to raise the voltage EXCEPT removing firm system load. Notify the RC and neighboring BA's. Prepare for manual load reduction if the voltage remains below .9 p.u. over the next 7 minutes.
A condition when a Load-Serving Entity has exhausted all other options and can no longer provide its customers' expected energy requirements is referred to as ____________?
A) Energy Emergency
B) Energy deficiency
C) Load shortage
D) Energy shortage
A) Energy Emergency
You are currently in the early stages of restoration with 600 MWs of synchronized generation. There is 200 MWs of spinning reserve available. To maintain acceptable frequency control, what is the largest block of load that can be restored at one time?
A) 10 MWs
B) 20 MWs
C) 30 MWs
D) 60 MWs
C) 30 MWs
If firm Load shed is imminent or in progress, what level Energy Emergency Alert is required?
Which of the following describes Power Factor?
A) Difference between real and reactive power
B) The ratio of real power and apparent power
C) Factors of magnetic strength
D) Equation to determine real power
B) The ratio of real power and apparent power
A Balancing Authority has a 200 MW/0.1 Hz frequency bias with zero schedules. Frequency is 60.00 Hz and ACE is 0, what should the sum of all the Balancing Authorities Interconnection ties equal?
A) Small MW amount out of the BA
B) System Load
C) Zero
D) Total Generation
C) Zero
A simple power system is composed of three transmission lines that connect the generation area to the load area. The three lines are different lengths, but each line has the same impedance. Each line is initially loaded at 200 MW. The SOL of each line is 400 MW. If one of the three lines trips, what will be the loading on the shortest remaining line and will the SOL of either remaining line be violated?
A) 400 MW/Yes
B) 400 MW/No
C) 300 MW/Yes
D) 300 MW/No
D) 300 MW/No
During a lightning storm, a fault on a transmission line results in the transmission relay operating and locking-out. The transmission line cannot be returned to service. After running a contingency analysis, the Transmission Operator realizes that if another transmission line relays, there could be cascading outages into a neighboring system. Which of the following actions is appropriate for the Transmission Operator?
A) Reduce transmission voltages by 5% to reduce customer demand.
B) Notify others in the Interconnection of the situation via an Interconnection- wide telecommunications system.
C) Continue operations without notifying anyone but try to reduce system loading.
D) Prepare a disturbance report and forward it to the Reliability Coordinator.
B) Notify others in the Interconnection of the situation via an Interconnection- wide telecommunications system.