PJM Exam Questions And 100% Accurate Answers
Leading phase when current is. - ANSWER Capacitive
What is the pass mark for a unit regulation test? - ANSWER 75% compliance with the test
signal
What resource generation is available in less than 10 minutes for offline reserves? -
ANSWER Quick-start
How does PJM avoid dealing with economic issues during transmission related
operational constraints? - ANSWER Cost (offer) capping generation
Which balance control mode does PJM use for normal operations? ANSWER Tie-line
bias
Three modes of control available to PJM dispatcher ACE control modes ANSWER Flat
Frequency Control, Flat Tie Line Control, Tie Line Bias Control
What is Flat Frequency Control? - ANSWER Uses only power system frequency as the
controlling parameter; responds only to frequency deviations; applies only when PJM
balancing area is islanded from the Eastern Interconnection
What is flat tie line control? - ANSWER Utilizes only interconnection tie line flow as the
controlling parameter; only responds to net tie flow deviations & does not adjust
operation for any frequency deviations; limited to special circumstances
What is tie line bias control? - ANSWER most widely used mode of control for
multi-balancing area power systems; responds to both frequency & net tie line flow
deviations
,To lower system voltage, MVAR must be shed in which direction to lower MW? -
ANSWER Decrease MVAR
What percent of regulation does PJM require for a system restoration? - ANSWER 2% of
current load
At what frequency will a system blackout? - ANSWER 57.5 Hz or lower
What minimum threshold is considered to be part of the BES? - ANSWER 100 kV or
greater
What is the Bulk Electric System (BES)? - ANSWER The electrical generation resources,
transmission lines, interconnections with neighboring systems, & associated equipment
generally operated at voltages 100 kV or higher
What are the limits that must be submitted to PJM for generating units? - ANSWER Eco
min, Eco max, Emergency Max
During high geomagnetic activity (>10 amperes at Missouri Ave or Meadowbrook
facility) what must be immediately implemented? - ANSWER Conservative operation
Other triggers that would call for conservative operations? - ANSWER fuel delivery
problems, forest/brush fires, environmental alerts, bad weather, terrorist or sabotage
threats against the BES, actual attacks against critical assets, PJM entering an
"unknown operating state"
What is conservative operations? - ANSWER PJM should implement additional actions
under specific events, conditions, or circumstances that could threaten the reliability of
the BES
What problems usually occur during minimum generation conditions? - ANSWER Excess
,generation online & high voltage
A unit is cost capped - WHEN During transmission related constraints
What is cost capping? - ANSWER Principles used by PJM when considering cost
containment provisions; all offers (cost & price) capped at $1,000/MWh by default and
offers over will need verification
If SCADA and ICCP go down, where should data be updated? - ANSWER EMS (Energy
Management System)
How often is reactive testing completed? - ANSWER Every 5 years
What mechanical device controls deviations in voltage? - ANSWER Load tap changer
For a generator unable to maintain its voltage schedule, who can approve a
replacement schedule? - ANSWER Transmission Owner
Under PJM's consideration, using what two elements for load forecasting? - ANSWER
Weather & day of the week
During system restoration, a generator should not be loaded above what level? -
ANSWER Dynamic Reserve
What is the dynamic reserve? - ANSWER the amount of reserve available to preserve the
system during a frequency disturbance; comprised of reserve on generators & load with
underfrequency relaying
What unit is allowed to set LMP? - ANSWER A unit that is dispatched for constraint
control
, At what fuel limit must PJM be notified for a black start unit? - ANSWER 10 hours
What is a black start unit? - ANSWER Generating units that are able to start without an
outside electrical supply or a unit with high operating factor to remain operating at
reduced levels when automatically disconnected from the grid
Why are black start units needed? - ANSWER necessary to restore the PJM transmission
system following a blackout; designate specific generators whose location &
capabilities are required to re-energize the system
Where does MET (meteorological) tower are used? - ANSWER Wind farms
Which generators must go through ICAP (installed capacity) testing? - ANSWER All
except wind & solar generators
What is ICAP (installed capacity)? - ANSWER The summer net capability of a generating
unit
What allows a circuit breaker between two control areas to be manually closed? -
ANSWER Synchroscope - shows the extent to which two systems are in sync with each
other
What does PJM monitor for three types of transmission constraints? - ANSWER
Reactive, Stability, Thermal (transfer limits)
To lower system voltage, it is necessary to reduce --- in order to reduce --- - ANSWER
MW, MVAR
The winter load shape in PJM has two peaks, true/false? - ANSWER TRUE
When corrections are made for the time error and the system schedule frequency must
Leading phase when current is. - ANSWER Capacitive
What is the pass mark for a unit regulation test? - ANSWER 75% compliance with the test
signal
What resource generation is available in less than 10 minutes for offline reserves? -
ANSWER Quick-start
How does PJM avoid dealing with economic issues during transmission related
operational constraints? - ANSWER Cost (offer) capping generation
Which balance control mode does PJM use for normal operations? ANSWER Tie-line
bias
Three modes of control available to PJM dispatcher ACE control modes ANSWER Flat
Frequency Control, Flat Tie Line Control, Tie Line Bias Control
What is Flat Frequency Control? - ANSWER Uses only power system frequency as the
controlling parameter; responds only to frequency deviations; applies only when PJM
balancing area is islanded from the Eastern Interconnection
What is flat tie line control? - ANSWER Utilizes only interconnection tie line flow as the
controlling parameter; only responds to net tie flow deviations & does not adjust
operation for any frequency deviations; limited to special circumstances
What is tie line bias control? - ANSWER most widely used mode of control for
multi-balancing area power systems; responds to both frequency & net tie line flow
deviations
,To lower system voltage, MVAR must be shed in which direction to lower MW? -
ANSWER Decrease MVAR
What percent of regulation does PJM require for a system restoration? - ANSWER 2% of
current load
At what frequency will a system blackout? - ANSWER 57.5 Hz or lower
What minimum threshold is considered to be part of the BES? - ANSWER 100 kV or
greater
What is the Bulk Electric System (BES)? - ANSWER The electrical generation resources,
transmission lines, interconnections with neighboring systems, & associated equipment
generally operated at voltages 100 kV or higher
What are the limits that must be submitted to PJM for generating units? - ANSWER Eco
min, Eco max, Emergency Max
During high geomagnetic activity (>10 amperes at Missouri Ave or Meadowbrook
facility) what must be immediately implemented? - ANSWER Conservative operation
Other triggers that would call for conservative operations? - ANSWER fuel delivery
problems, forest/brush fires, environmental alerts, bad weather, terrorist or sabotage
threats against the BES, actual attacks against critical assets, PJM entering an
"unknown operating state"
What is conservative operations? - ANSWER PJM should implement additional actions
under specific events, conditions, or circumstances that could threaten the reliability of
the BES
What problems usually occur during minimum generation conditions? - ANSWER Excess
,generation online & high voltage
A unit is cost capped - WHEN During transmission related constraints
What is cost capping? - ANSWER Principles used by PJM when considering cost
containment provisions; all offers (cost & price) capped at $1,000/MWh by default and
offers over will need verification
If SCADA and ICCP go down, where should data be updated? - ANSWER EMS (Energy
Management System)
How often is reactive testing completed? - ANSWER Every 5 years
What mechanical device controls deviations in voltage? - ANSWER Load tap changer
For a generator unable to maintain its voltage schedule, who can approve a
replacement schedule? - ANSWER Transmission Owner
Under PJM's consideration, using what two elements for load forecasting? - ANSWER
Weather & day of the week
During system restoration, a generator should not be loaded above what level? -
ANSWER Dynamic Reserve
What is the dynamic reserve? - ANSWER the amount of reserve available to preserve the
system during a frequency disturbance; comprised of reserve on generators & load with
underfrequency relaying
What unit is allowed to set LMP? - ANSWER A unit that is dispatched for constraint
control
, At what fuel limit must PJM be notified for a black start unit? - ANSWER 10 hours
What is a black start unit? - ANSWER Generating units that are able to start without an
outside electrical supply or a unit with high operating factor to remain operating at
reduced levels when automatically disconnected from the grid
Why are black start units needed? - ANSWER necessary to restore the PJM transmission
system following a blackout; designate specific generators whose location &
capabilities are required to re-energize the system
Where does MET (meteorological) tower are used? - ANSWER Wind farms
Which generators must go through ICAP (installed capacity) testing? - ANSWER All
except wind & solar generators
What is ICAP (installed capacity)? - ANSWER The summer net capability of a generating
unit
What allows a circuit breaker between two control areas to be manually closed? -
ANSWER Synchroscope - shows the extent to which two systems are in sync with each
other
What does PJM monitor for three types of transmission constraints? - ANSWER
Reactive, Stability, Thermal (transfer limits)
To lower system voltage, it is necessary to reduce --- in order to reduce --- - ANSWER
MW, MVAR
The winter load shape in PJM has two peaks, true/false? - ANSWER TRUE
When corrections are made for the time error and the system schedule frequency must
