500kV Oil-Immersed Power Transformer

Voltage Class

500kV

Rated Capacity Range

Single-phase two-winding: 100000 ~ 484000kVA Three-phase two-winding: 120000 ~ 1170000kVA Single-phase three-winding autotransformer: 120000 ~ 400000kVA

Voltage Regulation

No-load / on-load tap changing (tapping on the medium-voltage winding or voltage regulation at the medium-voltage terminal)

Vector Group

YNd11 (three-phase), Ii0 / Ia0i0 (single-phase)

Energy Efficiency

Loss level codes 18 / 20 / 22 (Energy Efficiency Level 3 / 2 / 1)

Summer-Peak Main Grid

Main power grid nodes with high load rate operating continuously under high ambient temperature.

Iron, Steel & Metallurgical Industry

Sites with impact loads and continuous overload requirements; the high-temperature resistant hybrid insulation system provides ample thermal margin.

Power Plants & Hydropower Stations

Large-capacity step-up/step-down transmission nodes combining high capacity with low-loss operation.

Railway Transportation

Traction power supply and other scenarios with fluctuating loads and strict continuous-overload requirements.

Low Loss

Both no-load loss and load loss comply with the latest GB20052-2024 national energy efficiency standard, and even surpass both Chinese GB and EU energy efficiency standards.

Low Noise

Self-cooling noise levels below 60dB — approximately 20dB lower than national standards — significantly reducing environmental noise pollution; custom-engineered ultra-low noise transformers available for specialized applications.

Low Partial Discharge

The entire manufacturing process is conducted in dust-free environments, with all internal metal and insulation components rounded. Partial discharge is kept below 100pC, guaranteeing stable and reliable operation.

Strong Short-Circuit Withstand Capability

Short-circuit mechanical forces are controlled through both design calculation and manufacturing process safeguards, ensuring safe and reliable power supply under sudden short-circuit conditions.

High Temperature Resistant & Safer

Operates continuously under 100% load at 40℃ ambient for the long term; at the same temperature the continuous load rate is 20% higher than that of conventional oil-immersed transformers.

High-Temperature Resistant Hybrid Insulation System

Nomex® insulation + transformer oil. Insulation materials of different temperature resistance grades are selected according to the temperature field distribution, so the whole insulation system reaches equal service life.

Seven-Step Temperature Control Technology

Five temperature levels extend from the winding hot spot outward to the low-temperature zone; short-circuit and overload conditions complete a seven-level thermal state for temperature control. Actual maximum oil temperature is set at 95℃, ensuring safety, thermal margin and long expected life.

Maintenance-Free & More Eco-Friendly

An equal-life design system delivers greater environmental sustainability throughout the lifecycle and reduces later operation and maintenance costs.

Low Carbon

Unique low-carbon design solutions and intelligent monitoring systems enable low-carbon operation throughout the entire lifecycle.

Leak-Proof

All seals are one-piece molded acrylate with no joints. Fluorescent, positive-pressure and negative-pressure leak detection ensure high sealing performance — no leakage, solemnly promised.

GB 20052-2024

Minimum allowable values of energy efficiency and energy efficiency grades for power transformers (no-load and load losses fully compliant)

GB 6451-2023

Technical parameters and requirements for oil-immersed power transformers (no-load losses reduced by over 20%, load losses by more than 5%)

IEC 60076

Power transformers

IEEE C57 Series

IEEE standards for power transformers (applied upon customer request)

Short-Circuit Withstand Design Safeguards

Short-circuit withstand capability enhanced through dual safeguards of design calculation and manufacturing process

R&D Cloud Platform

Integrates electromagnetic optimization design, parametric drawing, performance analysis, structural optimization and automatic drawing of transformers, realizing shared design resources plus search, modification and version control of all data.

Simulation Analysis

Internationally advanced electromagnetic simulation software — ANSYS Maxwell, JMAG, Infolytica MagNet — with multi-physics coupling simulation technology ensures optimal temperature and leakage magnetic field distribution in transformers.

Seven-Step Temperature Control Technology

Temperature field analysis software determines the winding hot-spot temperature distribution; insulation materials of different temperature grades are selected by temperature range so every component of the insulation system reaches the same service life — a design life of over 40 years.

Short-Circuit Withstand Safeguards

On the design side: ampere-turn balance calculation, semi-hard copper wire selection (Σ0.2 = 120~260MPa) and strength verification of clamps and pressure plates minimize short-circuit mechanical forces. On the manufacturing side: tight winding/sleeving/compression of the body, prestress application and strict winding height tolerance control after drying.

Intelligent Operation & Maintenance Platform

By collecting key data such as transformer temperature, current, voltage, vibration and grid harmonics, it realizes online power quality analysis and fault alarm, and can be installed on mobile phones.

Transformer Body Fastening Structure

Utility model patent 201721792681.5

New High-Voltage Large-Capacity Power Transformer

Utility model patent 202221985881.3

High-Voltage Bushing Arrangement for Vehicle-Mounted Mobile Transformers

Utility model patent 202222136876.1

High-Voltage Transformer with Integrated Sealing Cover

Utility model patent 202222505385.X

New Radiator Installation Form for Oil-Immersed Transformers

Utility model patent 202122652668.2

Main Equipment

15T horizontal winding machine, 20T vertical winding machine, 680kW vacuum drying equipment, 200T air cushion car