Technical Article

66/11 kV Transformer – Oil-Immersed Transformers

12-03 2025 | By:

66/11 kV oil-immersed transformers are widely used in power transmission and distribution networks, providing reliable voltage conversion for industrial, urban, and infrastructure projects. ZTelec Yuguang manufactures high-quality transformers with advanced design, ensuring high efficiency, long life, and low maintenance.

Common Applications

Urban Distribution: Step down voltage from 66 kV to 11 kV for city grids and residential areas.
Industrial Plants: Supply stable power for factories, heavy machinery, and manufacturing lines.
Infrastructure Projects: Airports, metro systems, hospitals, and large commercial complexes.
Renewable Energy Integration: Connect solar, wind, or hydro plants to the local grid.

66/11 kV oil-immersed transformers from ZTelec Yuguang, up to 20 MVA, are ideal for urban distribution, industrial plants, infrastructure, and renewable energy projects.

Applications & Specifications Table:

Parameter	Specification / Range
Primary Voltage	66 kV
Secondary Voltage	11 kV
Power Capacity	500 kVA – 20 MVA
Phase	3
Cooling Type	ONAN / ONAF (Oil Natural / Oil Forced)
Insulation Class	F / H
Manufacturer	ZTelec Yuguang
Typical Applications	Urban distribution, industrial plants, infrastructure, renewable energy

Notes:

ONAN / ONAF: Oil Natural / Oil Forced cooling
Insulation F / H: Suitable for different temperature rises and environmental conditions

Key Features:

Reliable oil-immersed design with high efficiency.
Flexible capacity up to 20 MVA for industrial and urban applications.
Advanced insulation for long-term performance.
Factory-direct supply ensures competitive pricing and fast delivery.

Conclusion

66/11 kV oil-immersed transformers from ZTelec Yuguang are ideal for industrial, urban, and renewable energy projects, combining high reliability, energy efficiency, and scalable capacity. Selecting the correct voltage and capacity ensures safe and stable power distribution.