35KV S20 Oil Immersed Transformer 50-5000KVA

1.Product Overview

S20 series 35kV three-phase dual-winding off-circuit tap-changing oil immersed power transformer covers rated capacity from 50kVA to 5000kVA,standard HV 35kV,customizable LV 10.5kV/6.6kV/0.4kV,50Hz.It is China Grade 2 high-efficiency energy-saving transformer complying with GB20052-2020/2024&IEC60076 global standards,upgraded from S13/S11 generation with optimized electromagnetic layout and high-permeability CRGO silicon steel core.

Model Definition

S=Three-phase;20=Tier 2 energy efficiency grade;M=Fully sealed corrugated tank for small capacity;standard off-circuit tap changer

2.Core Competitive Advantages

①Remarkable energy saving&reduced running cost

No-load loss drops~40%vs S11,~10%lower than S13;load loss reduces~20%against S13 standard.Total power consumption decreases around 25%,effectively cutting long-term idle&loaded electricity cost for substations,matching global energy conservation&carbon reduction policies.Core adopts 45°full-step skew lamination cutting technology to cut no-load current below 0.7%for big capacity models.

②Superior anti-short-circuit performance&stable operation

All active windings wound by 90%high-purity oxygen-free copper;low voltage below 500kVA uses double cylindrical winding,above 630kVA adopts helical/copper foil winding with uniform ampere-turn distribution.Whole core-coil assembly fixed by anti-loose steel clamping structure,passed full IEC short-circuit withstand test to avoid coil shift under sudden short-circuit surge;standard Dyn11 vector group suppresses grid harmonic pollution effectively.

③Dual tank design,anti-oil-leak&low maintenance

≤1600kVA:Fully sealed corrugated radiator tank without conservator;vacuum full oil filling isolates insulating oil from air to avoid oil oxidation&moisture intrusion,nearly maintenance-free in normal service.

≥2000kVA:Bell-type tank equipped with conservator&diaphragm oil storage,plate-fin radiator;optional ONAF forced air cooling fan to upgrade heat dissipation efficiency.

All flange seals adopt FKM high temperature oil-resistant rubber to eliminate long-time oil leakage trouble.

④Low noise&wide environmental adaptability

Shock-absorbing cushion under core and optimized core flux density control,running noise 10~18dB lower than national standard JB/T10088.Custom anti-salt-spray&anti-corrosion paint available for coastal,high altitude,chemical plant and unattended outdoor substation sites.

3.Main Technical Specifications

Capacity Range:50/100/160/315/500/800/1000/1600/2000/2500/3150/4000/5000kVA

Rated Voltage:HV:35kV±2×2.5%off-circuit tapping;LV:0.4kV/6.6kV/10.5kV customizable

Connection Group:Dyn11(Yyn0 optional upon request)

Cooling Mode:ONAN standard;ONAF forced air cooling optional≥2500kVA

Short-circuit Impedance:Standard 6.5%~7.5%,customized impedance acceptable

Executive Standard:IEC60076,GB/T1094,GB/T6451,GB20052-2024(Tier 2 Energy Efficiency)

Insulation Class:Class A,winding temp rise≤65K,top oil temp rise≤55K

4.Standard Optional Accessories

35kV high voltage porcelain bushing,conservator,dial oil level indicator,pressure relief device,winding temperature indicator,off-circuit tap switch,lightning arrester set,DIN/IEC standard terminal studs.

5.Application Fields

35kV regional substation,photovoltaic/wind farm booster station,mining&chemical enterprise power station,urban&rural grid upgrading,industrial park,prefabricated container substation,large commercial complex and residential district power supply project.