Transmission Line Parameters

1
????????????????? Transmission Line Parameters
Piyadanai Pachanapan, 303327 Power System
Engineering, EECPE, NU
2
???????

• ????????????????? (Overhead Transmission Line)

• ???????????????? (Line Resistance)

• ?????????????????? (Line Inductance)

• ?????????????????? (Line Capacitance)

3
?????? (Transmission Line)

• ????????????????????????????????????????????

• ?????????? ??????????, ???? ??????????? (Shield
  wires)

• ??????????????????????????? ???????
  ??????????????????? (???????? 1 )

• ???????????????????? ????????????????????????????
  ??????????? (69 kV, 115 kV, 138 kV, 161 kV, 230
  kV, 345 kV, 500 kV ??? 765 kV)

4
Overhead Transmission Line
Single Circuit
5
Overhead Transmission Line
220/230 kV
Double Circuit
6
Underground Transmission Line
7
????????????????????????
???????????????????? ????? ???????????
?????????????? ????????????????????????
?????????????????
????????????????? ????????

1. AAC All Aluminum Conductor
2. AAAC All Aluminum Alloy Conductor
3. ACSR Aluminum Conductor, Steel Reinforced
4. ACAR Aluminum Conductor, Alloy Reinforced

8
AAC All Aluminum Conductor

• ???????????????????????? ????????

9
AAA All Alulminum Alloy Conductor

• ??????????????????????? ????????? ????????

• ?????????????????? ??? AAC

10
ACSR Aluminum Conductor, Steel - Reinforced

• ??????? (Steel) ??????????? ?????????????????????
  ????

steel
11
ACAR Aluminum Conductor, Alloy Reinforced

• ????????????????????????????????? ???????????
  ?????????????????????????

• ??????? 7 ????
• ?????? 30 ???
• 2 ???? (2 layers)

12
??????????????????????
???????????????????
????????????????????????? ? Circular mils (cmil)
?????????????????? ? ??? (foot, ft)
???? SI
????????????????????????? ? ????????? (m2)
?????????????????? ? ???? (meter, m)
13
1 circular mil (cmil ???? CM)
- ????????????????????????????????????? (d) 1 mil
(1/1000 ????)
?????????????????????
d
???????
1 MCM 1,000 cmil
14
??????????? 1
???????????????? AAC ??? Hawkweed?????????????????
???????????????????????????? ?????????????????????
0.1644 ???? ????? 37 ???? ???????????????????????
???????????????????????????????? 1,000,000 cmil
????
1. ????????????????????????? ?????????????????????
2. ???????????????????????????????????
15
???
1 mil 1/1000 ????
1 ???? 1,000 mil

• ??????????????????????????????? (mils)

d
164.4 mils / ??? 1 ????

• ?????????????????????? (A) ????? cmil

16

• ??????????????????????? mm2

???
1 ???? ? 2.54 cm ? 25.4 mm

• ????????????????????????????????????? ???????

• ???????????????????????????????? ?????????