UHV 1200 kV AC Transmission
GRIDTECH 2007
Power Transmission
and Distribution
H. Huang, D.Kumar,
V. Ramaswami, D. Retzmann
Technical Alternatives for Bulk Power
Transmission
HVAC Systems
¾ 500 kV conventional as also series compensated
¾ 750 kV conventional as also series compensated
¾ 1200 kV conventional as also series compensated
HVDC Systems
¾ ± 500 kV bipole
¾ ± 550 kV bipole
¾ ± 600 kV bipole
¾ ± 800 kV bipole
Page 2
Dec.-06
PTD H 1T
Power Transmission and Distribution
Development of Voltages Levels
for AC Power Transmission
Voltage
1400
6
1200
kV
1000
5
800
600
400
2
200
4
3
experimental
in commercial use
1
1900
1910
1920
1930
1940
1950
1960
1970
1980
1990
2000
Year
Page 3
Dec.-06
PTD H 1T
Power Transmission and Distribution
EHV and UHV AC Systems – at Present
1000 kV Line:
SIL = 4 GW
Transmission
of 6-10 GW is
feasible
Page 4
ƒ Voltage Levels of 735 kV to 765 kV AC have been
introduced in the following Countries:
Canada, Brazil, Russia (USSR), South Africa,
South Korea, U.S.A. and Venezuela
ƒ UHV Transmission Lines (1000 kV and above)
have been built in Russia and Japan
ƒ Ekibastuz – Kokchetav (500 km)
ƒ Kokchetav – Kustanay (400 km)
ƒ Minami – Niigata / Nishi – Gunma (200 km)
ƒ Kita – Tochigi / Minami – Iwaki (250 km)
ƒ However, today these UHV Transmission Lines
are operated at 500 kV
Dec.-06
PTD H 1T
Power Transmission and Distribution
Product-Portfolio Non-Switching HV-Products
Coil Products
Bushings
Current and Voltage Transformer
Page 5
Dec.-06
PTD H 1T
Line Traps
Arrester
Power Transmission and Distribution
Product Range Live-Tank
High-Voltage Circuit-Breakers
Rated short-circuit
breaking current [kA]
80
3AT4/5
63
3AT2/3
50
40
31.5
25
0
3AP1 FG
72.5
123
3AP1 FI
145
170
245
3AP2 FI
300
362
420
550
800
1000
Rated voltage [kV]
¾ The existing C.B. product range is covering 800 kV
Scaling up to 1000 kV is possible
Page 6
Dec.-06
PTD H 1T
Power Transmission and Distribution
High-Voltage Circuit-Breaker 3AT4/ 5 EI up to 1000 kV
¾ EHVAC C.B. is using proven design
and can be scaled up from existing
550/800 kV type to 1000 kV
¾ R&D program may be decided for
1000kV according to specification
¾ Requirements for short circuit current
and higher altitudes above sea-level
have to be specified
¾ Ambient and environmental conditions
have to be considered
Page 7
Dec.-06
PTD H 1T
Power Transmission and Distribution
1000 kV EHVAC Double Break Disconnectors
from existing range of 800kV.....
Technical
Technical Data
Data
„
„ Rated
Rated voltage
voltage
„
Rated
lightning
„ Rated lightning impulse
impulse
withstand
withstand voltage
voltage (1,2/50
(1,2/50µs)
µs)
Across
the
isolating
distance
Across the isolating distance
„
Rated
„ Rated switching
switching impulse
impulse
withstand
withstand voltage
voltage
Across
Across the
the isolating
isolating distance
distance
„
„ Rated
Rated current
current
„
„ Rated
Rated short-time
short-time current
current
800
800 kV
kV
2100
2100 kV
kV
2235
kV
2235 kV
1300
1300
1725
1725
4000
4000
63
63
kV
kV
kV
kV
A
A
kA
kA
...to 1000kV design:
Up-scaling will cover the requirements on creepage distance &
mechanical strength of porcelain
Page 8
Dec.-06
PTD H 1T
Power Transmission and Distribution
1200 kV Power Transformer Prototype tested in 1972
¾ EHVAC Transformer using proven
design can be scaled up from existing
800 kV type
¾ R&D program may be decided for
1000kV according to specification
¾ Dielectric specification and transport
dimensions determine R&D cost and
time
¾ Test facilities are an open issue
Page 9
Dec.-06
PTD H 1T
Power Transmission and Distribution
Recent Activities for UHV
Example AC Test Transformer 1200 kV
Transformer & Reactor
Bushings:
Type OTA; Trench UK *, Oil-Paper
Technology
Production: Hebburn/UK, MWB
Shanghai/China
Design for 1200 kV Transformer is
available
Reference: Henjang / China
Page 10
**now
nowSiemens
Siemens
Dec.-06
Protected Creepage
Distance: 10.5 m
PTD H 1T
Power Transmission and Distribution
Development of UVH AC Transmission
Bundle of 8
Conductors
Rated Voltage:
1000 kV
Maximum Operation
Voltage: 1100 kV
Source:
Page 11
1000
Dec.-06kV Test Line
PTD H in
1T China
Power Transmission and Distribution
Road Map for UVH AC Transmission in China
1000 kV Pilot Project
Shaanbei
Jindongnan
Project Highlights:
„ Totally 650km Length
„ Including two UHV-AC Substations
and one Switchgear Station
Nanyang
Source:
Jingmen
Page 12
Dec.-06
PTD H 1T
Wuhan
Power Transmission and Distribution
Specific Issues – for UHV AC
The AC Measurements for UHV
Capacitive Voltage Divider
Type TEHMF Trench Canada *
Production: Toronto und Shanghai
In Service up to 800 kV
Scaling-up for 1100 kV is no Problem
**now
nowSiemens
Siemens
SF6 insulated CT and PT – Design is well proven
Type SAS, SVS; Trench Germany *
Production: Bamberg and Shanghai
In Service up to 800 kV
Scaling-up for 1100 kV is no Problem
Page 13
Dec.-06
PTD H 1T
Power Transmission and Distribution
Tower Configurations
19 m
15.5 m
48 m
92 m
16.5 m
50 m
44 m
71 m
108 m
16 m
Line conductors
Kita – Iwaki
Ekibastuz – Kokchetav
8 x 31,5 mm ACSR
8 x 24.1 mm AS-330
6,5
8
Air gap clearance
phase-earth [m]
Page 14
Dec.-06
PTD H 1T
Power Transmission and Distribution
Bundle Design and Tower Configuration
Voltage
Phase conductor wire
Outer diameter
Sub conductor spacing
1000 kV
8 x 403/52 ACSR
27.7 mm
400 mm
44 m
Ø = 1.07 m
Page 15
Dec.-06
PTD H 1T
Power Transmission and Distribution
Calculation of Overhead Line Characteristic
Resistance
Reactance
Capacitance
Surge impedance
Surge impedance load
Charging power
Maximum surface gradient
Page 16
Dec.-06
PTD H 1T
0.0107 Ω/km
0.267 Ω/km
14.15 nF/km
245 Ω
4080 MW
4.45 MVAr/km
14.7 kV/cm
Power Transmission and Distribution
Electric Field Strength
50 m
5 kV/ m - 10 kV/ m
10 kV/ m - 20 kV/ m
20 kV/ m - 50 kV/ m
50 kV/ m - 100 kV/ m
> 100 kV/ m
0m
-50 m
0m
50 m
Sectional view of the transmission line vertical to the line axis
Page 17
Dec.-06
PTD H 1T
Power Transmission and Distribution
Reactive Power Demand of Overhead Lines
as a Function of Load
Reactive Power
[MVAr/100 km]
600
1000 kV
400
750 kV
200
500 kV
380 kV
220 kV
0.5
0
1
1.5
P/SIL
-200
-400
-600
Page 18
Dec.-06
PTD H 1T
Power Transmission and Distribution
1000 kV AC Transmission Line
No-Load Operation
V1 = 100 %
V2
QC
Need of shunt compensation
Page 19
Dec.-06
PTD H 1T
L (km)
QC (Mvar)
V2/V1
250
1,133
1.04
500
2,417
1.17
750
4,169
1.50
1000
7,670
2.45
Power Transmission and Distribution
Transmission System with Shunt and Series
Compensation
P
SIL
Θ
Θ0
Kp = 0
Kp = Degree of
shunt comp.
Kp = 0
Kp (ind)= 0.5
Ks = Degree of
series comp.
Ks
Page 20
Load capability of transmission system
referred to the surge impedance load
Dec.-06
PTD H 1T
Ks
Transmission angle as a function of
degree of compensation
Power Transmission and Distribution
Load Capability of Transmission System
Referred to Surge Impedance Load (SIL)
P
SIL
Kp (ind.)
Kp (cap.)
Kp = Degree of shunt compensation
Page 21
Dec.-06
PTD H 1T
Power Transmission and Distribution
Power Frequency Overvoltage During
1-phase Auto-reclosing
5
V [p.u.]
4,5
Z0/Z1=2,0
Z0/Z1=1,0
degree of compensation
4
3,5
3
2,5
2
1,5
1
0,5
0
0%
10%
20%
30%
40%
50%
60%
70%
80%
90% 100% 110% 120% 130%
degree of shunt compensation
Power frequency overvoltage of disconnected phase during 1-phase
auto-reclosing for different Z0/Z1 ratios of shunt reactor
Page 22
Dec.-06
PTD H 1T
Power Transmission and Distribution
Ultra HVAC System > 1000 kV
„
Early research works on feasibility of 1100 kV system by AEP,
Furnas and some manufacturers.
„
Further research works on 1000 kV by ENEL-CESI in Italy
„
1100 kV TEPCO line in Japan ( 140 km)
„
1100 kV line in Russia operated at 500 kV as reported
„
1000 kV demonstration line with 3 substations are currently
under development in China
„
Conclusion:
UHVAC technology is technically feasible. R&D works are needed
on the equipment side
Page 23
Dec.-06
PTD H 1T
Power Transmission and Distribution