China 400kv 220kv 11kv 40mva Three Phase Three Winding Power Transformer

K. 400/200kV POWER
TRANSFORMERS (AIS-AIS)

UNIT

DATA

Required

Offered

1

POWER TRANSFORMER

1.1

Manufacturer & Place of
manufacturing

HEMG

1.2

Type designation

OSFSZ-200000/400

1.3

Type

Three phase Autotransformer, oil-immersed, core type with tertiary winding

Yes

1.4

Standards

IEC 60076, 60137, 60214

1.5

Altitude

m

216

1.6

Ambient temperature

- Maximum

ºC

40

- Annual average

ºC

30

1.7

Mounting

Outdoor

1.8

Rated voltage ratio

kV

400

220

11

1.9

Rated frequency

Hz

50

1.1

Vector group (3 phase group connection)

YNa0d11

1.11

Cooling- 2-stage

ONAN/ ONAF1/ ONAF2

1.12

Function of tertiary winding (TV)

Aux. supply

1.13

Method of earthing

- HV winding

Solid

- LV winding

Solid

- TV winding

-

1.14

Type of windings (graded/ non-graded)

- HV winding (Series)

Graded

- LV winding (Common)

Graded

- TV winding

Non-graded

1.15

Rated voltage of windings (Ur)

- HV winding

kV

400

- LV winding

kV

220

- TV winding

kV

11

Note*: approximate; to manufacturer's preference

1.16

Highest voltage for equipment (Um)

- HV winding

kV

420

- LV winding

kV

245

- TV winding

kV

12

1.17

Rated lightning impulse withstand voltage at:

- HV terminal

kV

1425

- LV terminal

kV

1050

- Neutral terminal

kV

480

- TV winding

75

1.18

Rated switching impulse voltage

- HV terminal

kV

1050

- LV terminal

kV

850

1.19

Rated power frequency withstand voltage at

- HV terminal (design value)

kV

630

- HV test value (ACLD U1)

kV

436

- HV test value (ACLD U2 PD measurement)

kV

388

- LV terminal (design value)

kV

460

- Neutral terminal

kV

70

- TV terminal

kV

28

1.2

Rated power at site conditions (ONAF2 or OFAF), HV & LV

MVA

200

1.21

Rated power at site conditions (ONAN)

MVA

120

1.22

Rated power of tertiary at site conditions (Full cooling)

MVA

70

1.23

Maximum temperature rise at rated power at:

- Windings

K

55

Marikani

- Hot spot of windings

K

68

Marikani

- Top oil

K

50

Marikani

- Oil at inlet of cooler

K

Approx 22

- Oil at outlet of cooler

K

Approx 50

- Core

K

Approx 75

1.24

Temperature of winding due to short circuit duration of 2s at rated load

- HV side short circuit rating of 31.5kA

ºC

250

- LV side short circuit rating of 31.5kA

ºC

250

1.25

No-load losses at rated voltage and rated frequency

kW

45

1.26

Load losses at 75ºC, and rated frequency:

- ONAF2 or OFAF rated power and principal tapping

288

- ONAF2 or OFAF rated power and maximum voltage ratio

- ONAF2 or OFAF rated power and minimum voltage ratio

278

- At onAN rated power and principal tapping

350

105

1.27

Total auxiliary losses at fully load

kW

Approx 10

1.28

Maximum current density at rated power:

- HV winding

A/mm2

Approx 2.0

- LV winding

A/mm2

Approx 2.0

- TV winding

A/mm2

Approx 3.6

- Tapping

A/mm2

Approx 3.6

1.29

Symmetrical short circuit through current (duration 2s) at system fault rating

- HV terminals (31.5kA)

kA

31.5

- LV terminals (31.5kA)

31.5

1.3

Magnetising current (HV winding)

- At 90% rated voltage

A

Approx0.7

- At 100% rated voltage

A

Approx0.9

- Ar 110% rated voltage

A

Approx6.8

1.31

Maximum flux density in iron at rated voltage, power frequency and principal tapping at:

- Wound limbs

T

Approx1.7

- Unwound limbs

T

Approx1.7

- Yokes

T

Approx1.7

- Shields

T

Approx1.7

1.32

Maximum flux density in iron at power frequency, principal tapping and 105% rated voltage at:

- Wound limbs

T

Approx 1.78

- Unwound limbs

T

Approx 1.78

- Yokes

T

Approx 1.78

- Shields

T

Approx 1.78

1.33

Type pf tap changing

On-load

On-load

1.34

Manufacturer of on-load tap changer

MR

1.35

Type designation of on-load tap changer

M500-72.5/C-10193W

1.36

Tapped winding

HV

HV

1.37

Type of flux voltage variation

V.F.V.V

V.F.V.V

1.38

Tapping range

-1

-1

1.39

Tapping step

1.25%

1.25%

1.4

Number of steps (positions)

16 (17)

16 (17)

1.41

Arrangement of tappings (Linear, Coarse/ Fine, Reversing)

Reversing

1.42

Automatic voltage control

Yes

Yes

1.43

HV - LV Impedance voltage range at 75°C, rated frequency and full rating:

- At principal tapping

%

>14%

>14%

- At maximum voltage ratio

%

>14%

>14%

- At minimum voltage ratio

%

>14%

>14%

1.44

Impedance voltage HV-TV (principle tapping) at 70MVA

%

Approx 22.5

1.45

Resistance of winding at 75ºC and principal tapping:

- HV side

Ω/phase

Approx 0.53

- LV side

Ω/phase

Approx 0.58

- TV

Ω/phase

Approx 0.029

1.46

Terminal connection

- HV terminal

Outdoor bushing

Outdoor bushing

- LV terminal

Outdoor bushing

Outdoor bushing

- Neutral terminal

Outdoor bushing

Outdoor bushing

- TV terminal

Outdoor bushing

Outdoor bushing

1.47

Bushing Creepage Distance (IEC class IV=31mm/kV)

- HV terminal (420kV)

mm

13020

13020

- LV terminal (245kV)

mm

7595

7595

- Neutral terminal (36kV)

mm

≥900

≥900

- TV terminal (12kV)

mm

372

372

1.48

Cable box insulation

- HV terminal

N/A

N/A

- LV terminal

"

N/A

- HV Neutral terminal

"

N/A

- LV Neutral terminal

"

N/A

- Tertiary

"

N/A

1.49

Isolating links for test purposes

- HV terminal

N/A

N/A

- LV terminal

"

N/A

- Tertiary terminal

"

N/A

1.5

Current transformers

HV- Bushing turrets

Refer to Tender Drawings

- Number of cores

3

- Rated extended primary current

500, 1000/500, 1000/500

- Ratio (TR= turns ratio)

•I core

A

500/1

•II core

A

1000/500/1

•III core

A

1000/500/1

- Class

•I core

5P20

•II core

5P20

•III core

5P20

- Knee point voltage (Ek)

•I core

V

1665

•II core

V

3330/ 1665

• III core

V

3330/ 1665

- Exciting current (IE) at EK

•I core

mA

Will provide measured value

•II core

mA

Will provide measured value

•III core

mA

Will provide measured value

- Rated output (Burden to be 25-100% rated burden)

•I core

VA

30

•II core

VA

30

•III core

VA

30

LV line (only AIS connections)

- Number of cores

3

- Rated extended primary current

1500, 750,750

- Ratio (TR= turns ratio)

"

1500/750/1; 750/1; 750/1

- Class

"

5P20

- Knee point voltage (Ek)

"

4995, 2498, 2498

- Exciting current (IE) at Ek

"

Will provide measured value

- Rated output (Burden to be 25-100% rated burden)

"

30

Neutral (HV REF)

- Number of cores

1

- Rated extended primary current

500

- Ratio (TR= turns ratio)

* I core

A

500/1

- Class

* I core

5P20

- Knee point voltage (Ek)

* I core

V

1665

- Exciting current (IE) at Ek

* I core

mA

Will provide measured value

- Rated output (Burden to be 25-100% rated burden)

* I core

VA

15

Neutral - ends

- Number of cores

1

- Rated extended primary current

500

- Ratio (TR= turns ratio)

•I core

A

500/1

- Class

•I core

5P20

- Knee point voltage (Ek)

•I core

V

1665

- Exciting current (IE) at Ek

•I core

mA

Will provide measured value

- Rated output (Burden to be 25-100% rated burden)

•I core

VA

15

All class PX CTs shall have a rated secondary current, ISN

A

1

Tertiary

- Number of cores

N/A

- Rated extended primary current

A

N/A

- Ratio (TR= turns ratio)

* I core

N/A

* II core

N/A

- Class

* I core

N/A

* II core

N/A

- Knee point voltage (Ek)

* I core

V

N/A

* II core

V

N/A

- Exciting current (IE) at Ek

* I core

mA

N/A

* II core

mA

N/A

- Rated output (Burden to be 25-100% rated burden)

* I core

VA

N/A

* II core

VA

N/A

1.51

Number of coolers per transformer

Approx 10

1.52

Number of stand-by coolers

N/A

1.53

Number of stand-by fans

1

1.54

Rating of each cooler

kW

0.75

1.55

Oil

- Manufacturer

Nynas Nitro

- Type designation

GBN1

- Standards

IEC 60296

IEC 60296

- Minimum flash point

ºC

140

- Viscosity

* at 20ºC

mm2/s

IEC 60296

* at 50ºC

mm2/s

IEC 60296

* at 80ºC

mm2/s

IEC 60296

- Maximum dielectric strength for 1 min.

kV

70

- Dielectric factor

0.005

- Acidity (neutralization value)

mgKOH/g

0.01

1.56

Oil preservation system

Air-bag

Air-bag

1.57

Types and arrangement of winding:

- HV winding

Disc

- LV winding

Disc

- TV winding

Disc

- Regulating

Disc

- Windings arrangement (i.e. Core/ TV/ LV/ HV/ Taps)

Core/ TV/Taps/ LV/ HV/

1.58

Conductor material (e.g., copper, work hardened copper, etc.)

- HV windings

Work hardened copper

- LV windings

Work hardened copper

- TV windings

Work hardened copper

- Regulating windings

Work hardened copper

- Connecting leads from winding to tap changer

Work hardened copper

1.59

Conductor insulation:

- HV windings

Paper

- LV windings

Paper

- TV windings

Paper

- Regulating windings

Paper

- Connecting leads from winding to tap changer

Paper

1.6

Calculated thermal time constant

- onAN cooling

min

Oil:210 windings:10

- Full cooling

min

Oil:90 windings:7

1.61

Oil circulation (i.e., natural/ partially directed/ directed)

To the windings:

- HV windings (Series)

Natural

- LV windings (Common)

Natural

- Regulating windings

Natural

- TV windings

Natural

Through the windings:

- HV windings (Series)

Derected

- LV windings (Common)

Derected

- Regulating windings

Natural

- TV windings

Derected

1.62

Core construction:

- Taped/ banded/ bolted limbs

Banded limbs

- Taped/ banded bolted yokes

Banded yokes

- Taping / banding material

Epoxy-bound bandage

- Number of limbs

3

- Number of limbs wound

3

- Type of joint in magnetic core (90% butt, overlap, mitre, etc.)

Overlap

- Type of core steel

23RK85

- Specific loss of core steel at 1.5 tesla

W/kg

Approx 0.7

1.63

Thickness of transformer tank

- Sides

mm

10

- Bottom

mm

10

- Top

mm

25

1.64

Material of transformer tank

Q235

1.65

Thickness of radiator plates

mm

1

1.66

Total volume of conservator

Litre

Approx 4000

1.67

Minimum volume of conservator between highest and lowest levels as percentage of total cold oil at 15ºC volume of transformer

7.50%

7.50%

1.68

Volumetric expansion of oil from 0ºC to 90ºC

m3

Approx 5.7

1.69

Pressure increase inside tank due to expansion of oil

N/A

1.7

Masses of transformer

- Core and coils

kg

Approx 93000

- Total mass excluded oil

kg

Approx 140000

- Oil mass * in tank

kg

Approx 61000

* in radiators

kg

Approx 2500

* total

kg

Approx 81000

- Total mass

kg

Approx 221000

1.71

Mass of transformer as arranged for transport (heaviest part)

kg

Approx 120000

1.72

Dimensions of transformer arranged for transport

- Height

m

- Width

m

- Length

m

1.73

Filling medium of transformer tank for shipment

Dry air

1.74

Maximum sound pressure level (NEMA TR1- 5dB(A))

dB(A)

82

82

1.75

Conservator vessel, radiators, fan grilles, control boxes or cubicles and pipework anticorrosion protection

Hot dip galvanized and painted

Hot dip galvanized and painted

1.76

Tank anticorrosion protection

Painted

1.77

Supply voltage for transformer auxiliaries

V

415/ 240 AC

415/ 240 AC

1.78

Control/ Protection voltage

V

110 DC

110 DC

1.79

Manufacturer quality assurance

Yes

Yes

- According to ISO 9000, 9001, 9002, 9003 and 9004

validity

validity

1.8

Type test certificate to be issued by:

- Independent laboratory or independently witnessed type test certificate

Yes

Yes

1.81

Special Tests to be performed:

As Type test= T

As Routine test= R

- Dielectric test- Chopped wave lightning impulse

Yes (R)

Yes (R)

- Dielectric test- Short duration AC (ACSD)

No

No

- Measurement of zero-sequence impedance

N/A

N/A

- Determination of sound levels

Yes (T)

Yes (T)

- Measurement of harmonics of no-load current

Yes (R)

Yes (R)

- Measurement of power of fan motors & oil pumps

Yes (T)

Yes (T)

- Determination of capacitance, windings to earth and between windings

Yes (R)

Yes (R)

- Measurement of insulation resistance to earth and loss angle of insulation system capacitances

Yes (R)

Yes (R)

- Vibration test

No

No