20/22kV Cast Resin Dry Type Power Distribution Transformer

Service condition

Normal Condition

Ambient temperature

Indoor

-5°C to +40°C

Outdoor

-10°C to +40°C

Humidity

90%

Altitude

≤1000m

Pollution

Level I-Light

Level II-Medium

Earthquake

UBC Zone 3

Special Condition

Ambient temperature

Indoor

-15°C to +40°C, -25°C to +40°C

Outdoor

-10°C to +50°C, -25°C to +40°C

-40°C to +40°C

Humidity

95%, 98%

Altitude

≤2000m, ≤3000m, ≤4000m

Pollution

Level III-Heavy

Level IV-Very Heavy

Earthquake

UBC Zone 4

K-factor

3, 5, 7, 9, 11, 13, 15, 17

Standard code

IEC 60076-11 Power transformers-Part 11: Dry-type transformers

IEEE C57.12.01 General Requirements for Dry-Type Distribution and Power Transformers Including Those with Solid-Cast and/or Resin Encapsulated Windings

Ratings

IEC

Rated Frequency

50Hz, 60Hz

Rated Voltage

3.6 kV – 7.2 kV – 12 kV – 17.5 kV – 24 kV – 36 kV

Rated Insulation Level

20kV – 40kV – 60kV – 75kV – 95kV – 125kV – 145kV – 170kV

Rated KVA

30kVA – 50kVA – 80kVA – 100kVA – 125kVA – 160kVA – 200kVA – 250kVA – 315kVA – 400kVA – 500kVA – 630kVA – 800kVA – 1000kVA – 1250kVA – 1600kVA – 2000kVA – 2500kVA – 3150kVA

IEEE

Rated Frequency

60Hz

Rated Voltage

2.5kV – 5.0kV – 8.7kV – 15.0kV – 25kV – 34.5kV

Rated Basic Impulse level

30kV – 45kV – 60kV – 75kV- 95kV – 110kV – 150kV – 200kV

Rated KVA

Single-phase transformer:

5kVA – 10kVA – 15kVA – 25kVA – 37.5kVA – 50kVA – 75kVA – 100kVA – 167kVA – 250kVA – 333kVA

Three-phase transformer:

15kVA – 30kVA – 45kVA – 75kVA – 112.5kVA – 150kVA – 225kVA – 300kVA – 500kVA – 750kVA – 1000kVA – 1500kVA – 2000kVA – 2500kVA – 3750kVA

Features

Design

--Guarantee of accurate temperature rise in windings; in case of enclosure IP/NEMA there is no de-rating

--Low working temperatures down to -25℃

--Possibility to include any kind of accessories

--Insulation class F,H(option)

Technology

1.Aluminum or copper foil disk in high voltage winding

2. Aluminum or copper foil full width in low voltage winding

3. Casting under vacuum

4. Low partial discharge values <10 pC

5. Smooth surface

6. Self extinguishing

7. Dust resistance thanks to sealed coils (option)

8. Silicon free (option)

9.Low induction level and step lap configuration granting lower noise level

10. High impulse voltage withstand

11 .High short circuit withstand (radial and axial)

Design options

--Reduced loss transformers

--Copper windings

--Low voltage transformers

--Class H transformers

--Reduced temperature rise

--Multiple primary voltage

--Multiple secondary windings

--Multi winding transformers (2, 3, 4 or 5 on the same core)

--Encapsulated low voltage windings

--Sealed or casted low voltage winding

--Impregnated high voltage windings

--Different location of high and low voltage connection terminals: top and bottom, both on the same side

--Special connection groups

--Autotransformer

--Variable speed drives (VSD), rectifiers and excitation transformers for 6, 12, 18 and 24 pulses

--Different coupling factors from 0.15 up to 0.9

--Earthing transformers

--Seismic and vibration reinforcement system

--Outdoor operation