SZ11/13/20/22-M Series 35kv Three-Phase Oil-Immersed Transformer
Product Overview
The 35kV Series power transformers incorporate advanced design principles with substantial improvements in materials, structural engineering, and manufacturing processes. The high/low-voltage clamping frames utilize steel straps combined with top and side beams to form a rigid frame structure, significantly enhancing core compression force and transportation impact resistance. These units deliver:
• Enhanced short-circuit withstand capacity
• Superior operational reliability with reduced losses
• Noise levels below industry standards
• Aesthetic industrial design
Performance benchmarks align with leading international equivalents in this class.
Share the model, quantity, drawing, destination and project requirement for a focused response.
Product Features
- Safe, Fireproof & Pollution-Free: Direct operation at load centers.
- High Mechanical Strength: Withstands short-circuits, minimizes partial discharges, ensures thermal stability, and extends service life.
- Efficient Cooling: Capable of overload operation with forced air cooling.
- Robust Surface Treatment: Degreased, derusted, sandblasted, and painted for superior moisture resistance, ideal for metallurgy, petrochemical, and humid/polluted environments.
- Eco-Friendly: Flame-retardant, explosion-proof, and maintenance-free.
- Compact & Lightweight: Easy transportation and installation.
- Secure Positioning: Fixed core-tank structure prevents displacement during transit and ensures long-term operational stability.
- High-Efficiency Core: Uses premium low-loss silicon steel laminations with multi-step mitered joints to reduce no-load losses and noise. Coils utilize paper-wrapped or self-adhesive transposed conductors to minimize load losses, lowering grid and user operating costs.



Performance & Dimensions

Technical Specifications
| Type | Rated capacity (kVA) | HV (kV) | Tapping range (%) | LV (kV) | Vector group | No-load loss 11#(W) | No-load loss 13#(W) | No-load loss 20#(W) | No-load loss 22#(W) | Load loss 11#(W) | Load loss 13#(W) | Load loss 20#(W) | Load loss 22#(W) | Impedance voltage (%) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Off-load tap-changing | 3150 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 3040 | 2400 | 2000 | 1700 | 23000 | 21900 | 20700 | 20700 | 7 |
| Off-load tap-changing | 4000 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 3610 | 2900 | 2300 | 2000 | 27300 | 25900 | 24600 | 24600 | 7 |
| Off-load tap-changing | 5000 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 4320 | 3500 | 2800 | 2400 | 31300 | 29700 | 28200 | 28200 | 7 |
| Off-load tap-changing | 6300 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 5240 | 4200 | 3400 | 2900 | 35000 | 33300 | 31500 | 31500 | 7 |
| Off-load tap-changing | 8000 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 7200 | 5800 | 4700 | 4000 | 38400 | 36500 | 34600 | 34600 | 7 |
| Off-load tap-changing | 10000 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 8700 | 7000 | 5700 | 4800 | 45300 | 43000 | 40800 | 40800 | 8 |
| Off-load tap-changing | 12500 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 10000 | 8000 | 6500 | 5500 | 53800 | 51100 | 48400 | 48400 | 8 |
| Off-load tap-changing | 16000 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 12100 | 9700 | 7900 | 6700 | 62500 | 59200 | 59200 | 59200 | 8 |
| Off-load tap-changing | 20000 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 14400 | 11500 | 9400 | 7900 | 79500 | 75500 | 71600 | 71600 | 8 |
| Off-load tap-changing | 25000 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 17000 | 13600 | 11100 | 9400 | 94000 | 89300 | 84600 | 84600 | 8 |
| Off-load tap-changing | 31500 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 20200 | 16200 | 13100 | 11100 | 112000 | 106400 | 100800 | 100800 | 10 |
| On-load tap-changing | 3150 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 3230 | 2600 | 2100 | 1800 | 24700 | 23500 | 22200 | 22200 | 7 |
| On-load tap-changing | 4000 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 3870 | 3100 | 2500 | 2100 | 29100 | 27600 | 26200 | 26200 | 7 |
| On-load tap-changing | 5000 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 4640 | 3700 | 3000 | 2600 | 34200 | 32500 | 30800 | 30800 | 7 |
| On-load tap-changing | 6300 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 5630 | 4500 | 3700 | 3100 | 36700 | 34900 | 33000 | 33000 | 7 |
| On-load tap-changing | 8000 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 7870 | 6300 | 5100 | 4300 | 40600 | 38600 | 36500 | 36500 | 7 |
| On-load tap-changing | 10000 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 9280 | 7400 | 6000 | 5100 | 48000 | 45600 | 43200 | 43200 | 8 |
| On-load tap-changing | 12500 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 10900 | 8700 | 7100 | 6000 | 56800 | 54000 | 51100 | 51100 | 8 |
| On-load tap-changing | 16000 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 13100 | 10500 | 8500 | 7200 | 66800 | 63300 | 63300 | 63300 | 8 |
| On-load tap-changing | 20000 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 15500 | 12400 | 10100 | 8500 | 82700 | 78600 | 74400 | 74400 | 8 |
| On-load tap-changing | 25000 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 18300 | 14600 | 11900 | 9780 | 97800 | 92900 | 88000 | 88000 | 8 |
| On-load tap-changing | 31500 | 35,38.5 | ±5 or ±2×2.5 | 3.15,6,3,10 | Dyn11 or Yd11 or YNd11 | 21800 | 17400 | 14200 | 12000 | 116000 | 110200 | 104400 | 104400 | 10 |
Applications
It is suitable for important locations with special fireproof requirements, such as commercial buildings, high-rise structures, airports, industrial and mining enterprises, power plants, oil platforms, subways, and tunnels. It can also be combined with switchgear to form prefabricated substations.

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