week 3 (chapter 3) Flashcards
the time of day when the demand for load is the highest?
peak load
when an outage on a circuit causes outages on interconnected circuits because the interconnected circuits are not able to support the load from the original outage…….this is called?
cascading
when is cascading most likely to happen?
during peak load times (early morning & evenings)
what best explains why there is a need for a smarter power grid?
strain on the grid during peak load
smart grid systems must be of the ____ ___ design
loop feed
where does much of the renewable energy come from on distribution systems?
dispersed micro generation & distributed generation
where does much of the renewable energy come from on transmission systems?
wind & solar thermal
when power can flow both directions through circuits and equipment it is called?
bi-directional energy flow
when distributed generation is adequate enough to handle load of a portion of the system (without dependence on the main grid), it is called?
islanding
generators that increase operation only during peak load time are called?
peaker plants
what type of hydro electric generation involves an upper reservoir that during peak load times will flow into a penstock to feed a generator and boost system voltage?
Pumped storage (because the water is pumped back up during low demand, ready for next use)
how long can molten salt from a parabolic trough solar generation system remain liquefied?
5-7 days
how is energy released from storage batteries during peak load times?
in short bursts
what method of stored energy uses caverns, mineshafts, and empty gas reservoirs?
compressed air
ACCC (aluminum conductor composite core) is found on?
transmission systems
what conductor on a transmission line can carry much more current at higher temperatures than the same sized ACSR conductor?
ACCC
PMU’s are found where?
substations
checks phase angle on voltage and current sine waves
phasor measurement units (PMU’s)
triggers operation of capacitors and reactors via satelite to operate when there are disturbances on the phase angles
PMU’s
philosophy that allows real time conditions surrounding conductors to be monitored
Dynamic line loading
one advantage of dynamic line loading is ________ ______ and it allows operators to view?
thermal imaging/ conductor temp
OPGW stands for?
optical ground wire
where is OPGW found and what is it used for?
transmission/fiber optic data transfer and shield wire
when larger portions of the circuit begin islanding it is called a?
micro grid
smart grid discussion s tend to lean toward?
distribution
what two objectives have to be met for smart switching equipment like cutouts, gang switches, and reclosers?
provide means for isolation and sectionalizing
change direction until the system returns to normal (bi directional )
what kind of recloser can be operated by SCADA and can be set to either single phase or multi phase lock out?
smart
what kind of recloser is operated via hydraulics?
legacy
seen on single phase taps/can be retro fitted to a legacy cutout gate and indicates real time load?
smart cutout (tripsaver)
what are the two types of capacitor banks?
fixed (legacy) and switched (smart)
the intentional lowering of system voltage to help reduce demand on the system?
conservation voltage reduction
why are distribution taps purposely lowered to the low end of the required service voltage range of 114-126?
to reduce system demand
can be quickly installed on a conductor to provide data for troubleshooting and localized power quality disturbances
fault indicators & sensors
home owner plays a more active role in power consumption
smart home
when customers can monitor, manage, & control energy usage via home area display units or cell phones, this is called?
demand-side management
smart meters and homes are subject to?
hacking
relays price changes to the home area display unit, then talks to smart appliances?
smart meter
can be plugged into appliances to see usage?
smart plug
what is estimated to be the second biggest energy usage in the home?
lighting
what is it called when lights are dimmed in place of using natural daylight?
daylight harvesting
what voltage can power an electric vehicle?
120
what type of vehicle cannot pull a horse trailer but will haul you and your fanny pack to starbucks for a 1000 calorie latte with just 120 volts of electricity?
all electric vehicle
