INTRODUCTION OF INTRODUCTION OF ULTRA-HIGH VOLTAGE (UHV) ULTRA-HIGH VOLTAGE (UHV)
1000 kV AC TRANSFORMER1000 kV AC TRANSFORMER
Presented By
Zhijin ChenTBEA Shenyang Transformer Group Co. Ltd. China
Structure of 1000kV AC Structure of 1000kV AC Transformer Transformer
Parameters Parameters of of
1000kV/1000 MVA UHV AC 1000kV/1000 MVA UHV AC Transformer Transformer
Made by TBEA, ChinaMade by TBEA, China
1) Rated Capacity
HV Winding : 1000 MVA
MV Winding : 1000 MVA
LV Winding : 334 MVA
2) Rated Voltage
HV Winding : 1050/√3kV
MV Winding : 525/ √3 ±4×1.25%kV
LV Winding : 110kV
3) Rated Frequency : 50Hz
4) Three-phase Connection Symbol : YNa0d11
5) Nominal Short-circuit Impedance (based on 1000MVA) : HV - MV : 18%
HV - LV : 62%
MV - LV : 40%
6) Type of Cooling : Main Transformer - OFAF
Voltage-regulating Transformer - ONAN
7) Temp. Rise Limit Value :
Winding : 65K
Top Oil : 55K
Hot-spot: 78K
Tank Surface : 80K
8) Total weight of Main Transformer : 535 ton
Total weight of Voltage-regulating Transformer : 143 ton
9) Internal Insulation Level :
Rated Short-time Power-frequency
Withstand Voltage (r.m.s.
value , 5min )
Rated Switching Impulse Withstand Voltage ( relative
peak value )
Rated Lighting Impulse Withstand Voltage ( peak
value )
Full WaveChopped
Wave
HV 1100 kV 1800 kV 2250 kV 2400 kV
Rated Short-time Power-frequency
Withstand Voltage ( r.m.s. value ,
1min )
Rated Switching Impulse Withstand
Voltage (relative peak value)
Rated Lighting Impulse Withstand Voltage (peak
value)
Full WaveChopped
Wave
MV 630 kV 1175 kV 1550 kV 1675kV
Neut. 140 kV / 325 kV /
LV (Tert.)
275kV / 650 kV 750 kV
Technical Applied Technical Applied on on
Design and Production Design and Production of of
1000kV/1000 MVA UHV AC 1000kV/1000 MVA UHV AC TransformerTransformer
-- Main Insulation
-- Longitudinal Insulation
-- 1000kV Leads
-- Magnetic Leakage & Losses
-- Winding Temp. Rise
-- Short-circuit Withstand Capability
-- Strength of Tank Transportation
-- Seismic Strength
Key Technical Characteristic Studies——Longitudinal Insulation
Potent i al Di st r i but i on undedr Ful l Wave I mpusl e
0
0. 2
0. 4
0. 6
0. 8
1
1. 2
0 10 20 30 40 50us
oten
tial
of
Full
Wav
e Im
puls
e Vo
ltag
e %
G1 G2 G4G10 G18 G24G26
Gradient voltage distribution under full wave lighting impulse-0. 04
-0. 02
0
0. 02
0. 04
0. 06
0. 08
0 5 10 15 20 25 30 35 40 45 50usFu
ll w
ave
impu
lse
volta
ge (%
)
HV wi ndi ng 1 oi l -ductHV wi ndi ng 3 oi l -ductHV wi ndi ng 5 oi l -ductHV wi ndi ng 7 oi l -duct
Creepage gradient distribution under full wave lighting impulse-0. 15
-0. 1
-0. 05
0
0. 05
0. 1
0. 15
0. 2
0. 25
0 5 10 15 20 25 30 35 40 45 50
us
Full
wav
e im
puls
e vo
ltage
(%)
Impulsive creepage gradient distribution ofHV winding (first 100mm)
Impulsive creepage gradient distribution ofHV winding (first 200mm)
Impulsive creepage gradient distribution ofHV winding (first 300mm)
Gradient distribution under chopped wave lighting impulse- 0. 03
- 0. 02
- 0. 01
0
0. 01
0. 02
0. 03
0. 04
0. 05
0. 06
0. 07
0 5 10 15 20 25 30 35 40 45 50us
Cho
pped
wav
e im
puls
e vo
ltage
(%)
HV wi ndi ng 1 oi l - ductHV wi ndi ng 3 oi l - ductHV wi ndi ng 5 oi l - ductHV wi ndi ng 7 oi l - duct
Potential distribution under chopped wave lighting impulse-0. 4
-0. 2
0
0. 2
0. 4
0. 6
0. 8
1
0 5 10 15 20 25 30 35 40 45 50usC
hopp
ed w
ave
impu
lse
pote
ntia
l (%
)
G1 G2 G4
G10 G18 G24G26
Electric field intensity distribution at the middle part between LV and HV windings
Electric field intensity distribution at the end between
LV and HV windings
Electric field intensity distribution of main insulation
calculation by utilizing ANSOFT at the end between
LV and HV windings
Electric field intensity distribution of main insulation
calculation by utilizing ANSOFT at the middle part
between LV and HV windings.
Key Technical Characteristic Studies——1000 kV Leads
—Magnetic Leakage & Losses
5 Limb Core with 3 Parallel Wound Legs Required Stringent Quality Control to Prevent Circulating Current Losses
Key Technical Characteristic Studies——Winding Temp. Rise
Key Technical Characteristic Studies——Short-circuit Withstand Capability
Axial forces on a disc of a winding during short circuit
TV winding radial and axial leakage flux distribution
——Strength of Tank Transportation
Diagram of tank metamorphose under transportation condition
Enlarged diagram of tank stress under
transportation condition
——Seismic Strength
Diagram of stress distribution under
earthquake situation
Diagram of transformer bushing displacement response
during earthquake….long bushing needed special analysis
Some Testing Results Some Testing Results on on
The Product The Product of of
1000kV/1000 MVA UHV AC 1000kV/1000 MVA UHV AC TransformerTransformer
Required Value Product Trail Value
HV Partial Discharge Level
≤100pc 25pc
MV Partial Discharge Level
≤200pc 60pc
LV Partial Discharge Level
≤300pc 20pc
Required Value Product Actual Value
Top Oil Temp. Rise 55K 25K
HV Winding Temp. Rise 65K 45K
MV Winding Temp. Rise 65K 53K
LV Winding Temp. Rise 65K 49K
Tank Hot Spot Temp. Rise
80K 40K
No-load Audible Sound 75dB(A) 74dB(A)
Load Audible Sound 75dB(A) 75dB(A)
Total losses tested
Guarantee Final Test
Load loss, kW 1580 1477.7
No load loss, kW 200 199.9
The construction of The construction of
China’s first 1000kVChina’s first 1000kV
UHV transmission UHV transmission
project was project was
completed completed
successfully in 2008, successfully in 2008,
and passed 168-hour and passed 168-hour
full load energized full load energized
performance test in performance test in
January 2009.January 2009.
Thank You!Thank You!
TBEA Shenyang Transformer Group Co., Ltd.
TBEA Shenyang Transformer Group Co., Ltd.