Transcript Bus 3 UT Designing the Texas Grid from Scratch

Designing the Texas Grid from Scratch
LOAD
(% OF
TOTAL)
GEN
(% OF
TOTAL)
1, HOU
30%
45%, (40%)
2, DFW
25%
20%, (15%)
3, UT
5%
5%
4, SA
20%
10%, (5%)
5, VAL
10%
5%
6, COAL
5%
15%, (10%)
7, WIND
5%
0%, (20%)
BUS
Bus 2
DFW
250 km
Bus 6
COAL
500 km
Bus 7
WIND
300 km
400 km
With no wind, (with full wind)
Bus 3
UT
• Overload constraint: Transmission circuits are
not overloaded, either normally or when any single
transmission circuit is outaged.
• Import constraints: Each bus should be able to
import at least one-fourth of its load P (if others
can provide it).
• Stability constraint (approx.): Voltage phase angle
difference between adjacent busses should not
exceed 45º.
Bus 1
HOU
150 km
Bus 4
SA
• Q Limits: Uncorrected load PF = 0.90, and
generator PF rating cannot be less than 0.90.
Note – for simplicity, assume Q = 0.5 * P to achieve
PF ≈ 0.90)
• Transmission towers have two circuits.
• Use 100 MVA, 345 kV base.
• R = 0.05 Ω/km (for the bundle)
• L = 1 µH/m
300 km
• C = 12 pF/m
• Rating = 1600 A (for the bundle)
• Reactive power constraint: Each bus should have
enough local Q sources (gens, caps, or SVCs) to
provide at least one-half its load Q.
• Voltage constraint: Voltages should be in the
range of 1.00 – 1.05pu.
Positive-sequence line constants
for one 345kV circuit with doublebundled conductors:
• Summer Peak, 3 kW per person, 20
million people, 60 GW
400 km
• Winter Peak is 80% of Summer Peak
Bus 5
VAL
Do
spring/fall
first
• Spring/Fall Peak is 50% of Summer
Peak
• Nightime is 50% of Daily Peak
• Assume 5% losses