630kVA 20/0.4kV Power Transformer

Additional information

Primary Voltage Ratings: 20kV

Secondary Voltage Ratings: 400V

CONNECTION TYPE: Dyn11

TYPE: OIL TYPE

Standards: IEC

Power Rating: 630kVA

Cooling Method: ONAN

Our 630 kVA transformer is designed for the Spanish market with a primary voltage of 20 kV and a secondary voltage of 0.4 kV. It features a winding temperature rise of 55ºC and a top oil temperature rise of 50ºC. With no-load losses of 940 W and load losses of 5600 W, it offers high efficiency. The transformer includes porcelain bushings, robust insulation, and oil specifications meeting IEC 60296-2003 standards, ensuring reliability and performance for industrial and utility applications.

Our 630 kVA power transformer is engineered for optimal performance in the Spanish market, featuring a primary voltage of 20 kV and a secondary voltage of 0.4 kV. Designed with a winding temperature rise of 55ºC and a top oil temperature rise of 50ºC, this transformer ensures reliable operation under specified site conditions.

Key Specifications:

Voltage Ratio: 20/0.4 kV
Rated Power: 630 kVA
Winding Temperature Rise: 55ºC
Top Oil Temperature Rise: 50ºC
Impedance Voltage: 6% (at 75ºC, rated power, and principle tapping)

Losses:

No Load Losses: 940 W
Load Losses: 5600 W (at rated power and 75ºC)
Total Losses: 6540 W (at 75ºC)

Withstand Voltages:

Power Frequency Withstand Voltage:
- 20 kV winding and bushing: 50 kV
- LV winding and bushing: 3 kV
Impulse Withstand Voltage 1.2/50 µs:
- 20 kV winding and bushing: 125 kV peak
- LV winding and bushing: 6 kV peak

Magnetic Properties:

Maximum Flux Density: 1.7 Tesla

Conductor Specifications:

20 kV Winding: ≥ 4.2 mm²
LV Winding: ≥ 364 mm²

Insulation and Oil:

Type and Class of Insulation: Class A
Transformer Oil (per IEC 60296-2003):
- Viscosity at 40ºC: Max 12 mm²/s
- Viscosity at -30ºC: Max 1800 mm²/s
- Flash Point: Min 140ºC
- Pour Point: Max -30ºC
- Appearance: Clear, free from sediment and suspended matter
- Acidity: Max 0.01 mg/KOH/g
- Density at 20ºC: Max 0.895 g/ml
- Sludge: Max 0.8%
- DDF at 90ºC: ≤ 0.005
- Breakdown Voltage (after laboratory treatment): Min 70 kV

Construction and Design:

Tank Cover Thickness: 6 mm
Tank Bottom Thickness: 6 mm
Side Thickness: 1.2 mm (at least two longitudinal sides corrugated)

Bushings:

Material: Porcelain
Rated Current (MV/LV): 250/1500 A
Creepage Distance (MV/LV): 500/75 mm

Tapping and Adjustment:

Tapping Range: 2 × 2.5%
Number of Taps: 5

Applications:

This transformer is ideal for various industrial and utility applications, offering robust performance and reliability with high efficiency and safety. It meets all relevant standards and regulations for operation in Spain, providing a reliable solution for your power distribution needs.