e-grid 1 chapter 7-8

name the 5 environmental factors of a substation

1) appearance 2) electromagnetic fields 3) Sounds 4) oil spill containment 5) Fencing

describe the functions of a substation

1) change the voltage of circuits from one level to another 2) connector disconnect lines or equipment from each other 3) control the flow of power by adjusting the voltage and current

describe the different types of substations

1) generation substation. steps up the voltage 2) transmission substation to change the voltage levels to help integrate a system 3) subtransmission substation change the voltage from higher transmission voltages to lower voltage 4) distrabution substation located in the middle of the load center, they lower voltage again for subdivision.

name the three types of insulators

1) porcelain (suspension and line post) 2) polymer (suspension and line post) 3) glass (suspension)

identify the components of a substation

1)ground grid 2) voltage regulators 3) current and potential transformers 4) disconnect switches 5) circuit breakers 6) power transformers 7) steel structures 8) capacitors and reactors

what is the largest size of conductor that can be used and weight?

1-3/4 in, 2-1/2 lbs. per foot.

how deep is a ground grid typically buried

12-18in

sub transmission voltages are?

138kv, 115kv, 69kv, 44kv

how many conductors are there per phase in a bundled conductor?

2-4 per phase.

main grid voltages are?

765kv, 500kv, 345kv, 230kv

what is a determining factor of a right-of-way

Electromagnetic fields

WHAT IS LTC?

Load Tap Changer.

What does a power transformer do

They change voltage from one level to another. also some contain load Tap changers.

what is a ground grid?

a ground drid grid consists of large stranded copper wire very 12 to 18 inches below the ground. in a grid pattern of 8 to 20 foot squares

how far apart on average are transmission structures

about 1,000 feet.

what is it called if you have more than one conductor for one phase

bundled conductor

_____ uses gas, air, vacuum, or sulfer-hexafloride.

circuit breakers

what does a circuit breaker do

connect or disconnect lines and equipment. also to protect from fault current.

What insulator generally has higher rating.

dead end

what is the other function besides a path to ground of a shield wire?

fiber optic/ communication wire.

what type of structure is used for 345kv and above

lattice type steel

what are the factors that are used to determine what size and type of conductor?

length of the line, span lengths, weather environment, line loss, and cost.

a 345kv transmission line is buried underground and typically uses ______ to cool it.

oil

"shield" wire and "static" wire are used for what?

path to ground for lightning surges.

_____ uses fans and oil to cool it's coils

power transformer

what are the three reasons we use bundled conductors?

reduce radio noise, reduce carona effect, and increase the capacity of the transmission line.

what is carona loss

refers to a phenomenon that occurs at high voltages, which is the result of ionization of the air around the conductor. carona effects are audible, and are visible at night.

what is not considered part of the main transmission grid

sub transmission lines

current and potential transformers do what

these devices provide a reduction in the voltage and current so the power flow can be measured, also senses abnormal amounts of voltage and current.

what do capacitors and reactors do

they're used to assist in a controlling the flow of power on the system

it takes 3 to 5 years to do what?

to secure rights-of-way to build a major transmission line

what type of structure is used for 345kv and lower

wood structure