12500kVA 16000kva 20000kva 35kv 10.5kv Oil Immersed Transformer

12500kVA 16000kva 20000kva 35kv 10.5kv Oil Immersed Transformer

1. Product Description

The 12500kVA 16000kVA 20000kVA 35kV 10.5kV oil immersed transformer is a heavy-duty high-capacity three-phase power transformer designed for 35kV high-voltage power grid systems. As a core industrial-grade oil-filled step-down transformer for large-scale power distribution and power station projects, this 35kV to 10.5kV oil immersed power equipment specializes in converting high 35kV medium-high grid voltage into stable 10.5kV industrial standard voltage, perfectly matching the power supply demands of large industrial bases, regional power substations and new energy power generation grid-connection systems. Manufactured in full compliance with IEC60076 and GB/T6451 international electrical standards, this large-capacity oil immersed distribution transformer adopts upgraded S13/S18 energy-saving technology, solving high energy consumption and unstable operation problems of traditional old-generation high-power transformers.

Built with high-grade low-loss grain-oriented silicon steel core and high-purity oxygen-free copper integral windings, the 12500kVA, 16000kVA and 20000kVA 35kV 10.5kV oil immersed transformer effectively minimizes no-load magnetic loss and load operating loss. Equipped with thickened bell-type oil tank and professional ONAN/ONAF oil cooling system, this sealed oil immersed power transformer features excellent heat dissipation performance and strong short-circuit impact resistance. Different from medium and small-capacity transformers, this series of high-power transformers is customized for long-term full-load continuous operation, with stable insulation performance, low operating noise and outstanding grid adaptability. It is the key power transformation equipment for urban power grid expansion, industrial park supporting power supply and large photovoltaic and wind power grid-connected projects.

2.  Technical Parameters

3. Core Purpose

The core purpose of the 12500kVA, 16000kVA and 20000kVA 35kV 10.5kV oil immersed transformer is to provide high-efficiency, stable and safe large-capacity voltage conversion for 35kV high-voltage power transmission and distribution systems. This heavy-duty oil-filled step-down transformer solves the voltage level mismatch between 35kV regional transmission grids and 10.5kV industrial power distribution systems, converting high-voltage transmission power into standard 10.5kV medium-voltage power suitable for large industrial equipment, factory centralized power supply and secondary substation power distribution.

In actual power grid operation, this high-capacity three-phase oil immersed power transformer undertakes core functions including regional grid voltage stabilization, large-load power shunting, three-phase load balancing and power system safety isolation. It effectively suppresses power grid harmonics, voltage fluctuation and instantaneous current surge caused by large-scale load switching, greatly improving regional power supply quality and grid operation stability. Designed for ultra-large long-term continuous loads, it eliminates power supply bottlenecks of industrial clusters and power stations, avoids equipment failure and power outage risks caused by overload and voltage instability, and supports stable and efficient operation of 35kV high-voltage power grid systems.

4. Application Scenarios

Featuring ultra-large load capacity, excellent short-circuit resistance and long-term full-load operation stability, the 12500kVA 16000kVA 20000kVA 35kV/10.5kV oil immersed power transformer is widely used in high-power, high-reliability required power supply scenarios. It is the core key equipment for 35kV power grid construction, industrial supporting power supply and new energy grid-connected projects:

• Regional 35kV Substation Construction: Suitable for urban regional primary and secondary substations, county-level centralized power supply stations and industrial zone special substations. The three capacity models can be flexibly matched according to regional power load scale to realize stable step-down power distribution of high-voltage grids.

• Large Industrial Cluster Power Supply: Ideal for heavy industrial bases, chemical industrial parks, metallurgy and mining industrial zones and large manufacturing clusters with ultra-high centralized power consumption. It supports long-term full-load operation of multiple high-power industrial production equipment and assembly lines.

• Large New Energy Grid-connected Projects: Widely applied in large-scale centralized photovoltaic power stations, onshore wind power bases and energy storage power stations. It completes high-capacity voltage conversion and grid-connected power regulation for new energy power generation equipment, stabilizing new energy grid access power quality.

• Power Grid Upgrading & Capacity Expansion Projects: Used for renovation and capacity expansion of old 35kV power grids, replacing traditional high-loss low-capacity transformers to improve regional power grid transmission capacity and energy-saving operation efficiency.

• Key National Infrastructure Projects: Matched with large water conservancy hubs, railway transit supporting facilities, mining development bases and regional key engineering projects, providing 24-hour uninterrupted high-power stable power guarantee.

• Commercial & Civilian Centralized Power Distribution: Applicable for super-large urban business districts, large-scale comprehensive residential communities and regional commercial economic zones, undertaking large-scale civilian and commercial centralized power distribution tasks.

5. Product Features

This series of 12500kVA, 16000kVA and 20000kVA 35kV 10.5kV oil immersed transformers adopts advanced high-capacity energy-saving design and precision heavy-duty manufacturing technology. Compared with traditional large-power transformers, it has comprehensive advantages in energy-saving performance, operational safety, structural durability and load adaptability, fully meeting the harsh operation requirements of modern 35kV high-voltage power grids:

• Ultra-low Loss & High Energy-saving Efficiency: Adopts high-permeability low-loss silicon steel core and full oblique lap stacking process, which minimizes magnetic leakage and no-load iron loss. The integral oxygen-free copper winding structure reduces internal resistance and load copper loss significantly. All loss indicators reach national first-class energy efficiency standards, effectively reducing long-term power grid operation energy consumption and operational costs.

• Super Stable Voltage Output & Strong Anti-interference: Advanced YNd11 vector group design realizes precise three-phase voltage and current balance, effectively suppressing grid harmonic interference and voltage deviation. The multi-grade on-load and off-circuit dual voltage regulation modes adapt to complex grid voltage fluctuations, ensuring continuous and stable 10.5kV standard voltage output.

• Reinforced Fully Sealed Structure: Adopts thickened bell-type oil tank and fully sealed welding process, completely isolating internal insulating oil and core windings from external humid air, dust and corrosive substances. It avoids oil aging, moisture ingress and insulation degradation, effectively solving common oil leakage problems of large transformers.

• Excellent Heavy-load & Short-circuit Resistance: Optimized internal winding reinforcement structure and enhanced insulation design greatly improve short-circuit impact resistance and overload tolerance. The dual ONAN/ONAF cooling system provides efficient and balanced heat dissipation, ensuring stable operation under long-term full-load and peak overload conditions.

• High Safety & Low Failure Rate: Strict 35kV high-voltage insulation grade design with 200kV lightning impulse withstand level provides excellent over-voltage, lightning protection and over-current protection capabilities. The whole machine has stable mechanical strength and electrical performance, with extremely low operational failure rate in long-term heavy-load operation.

• Strong Environmental Adaptability & Low Maintenance: The whole machine adopts heavy-duty anti-corrosion electrostatic spraying process, resisting ultraviolet aging, rain erosion and high-low temperature alternating impact. The standardized modular structure simplifies daily inspection and maintenance work, reducing later operation and maintenance labor and time costs.

6. FAQ (Frequently Asked Questions)

Q1: How to choose among 12500kVA, 16000kVA and 20000kVA 35kV 10.5kV oil immersed transformers?

All three models adopt the same 35kV/10.5kV voltage level, insulation standard and structural process, with the core difference lying in rated load capacity and applicable scenarios. The 12500kVA oil immersed transformer is suitable for conventional regional substations and medium-sized industrial parks with stable conventional loads, featuring balanced energy consumption and cost performance. The 16000kVA high-capacity transformer is ideal for large industrial clusters and suburban grid expansion projects with medium peak power consumption. The 20000kVA ultra-large capacity model is customized for super-large new energy power stations, heavy industrial bases and key infrastructure projects with ultra-high load demand. It is recommended to reserve 20%–30% load margin during selection to cope with future power load growth.

Q2: Can this high-capacity 35kV 10.5kV oil immersed transformer operate stably in harsh outdoor environments?

Yes, this series of large-power oil immersed transformers is fully optimized for outdoor substation harsh working conditions. The reinforced fully sealed oil tank structure completely isolates internal electrical components from external moisture, dust and corrosive gas, preventing insulation damp failure and insulating oil deterioration. The heavy-duty weather-resistant shell can resist long-term ultraviolet radiation, heavy rain erosion, low-temperature freezing and high-temperature aging. The efficient dual cooling system automatically adjusts heat dissipation efficiency according to load changes, supporting 24-hour uninterrupted full-load operation all year round, fully meeting long-term unattended operation requirements of outdoor 35kV substations.

Q3: What key maintenance items are required for high-capacity 35kV oil immersed transformers?

This large-capacity 35kV 10.5kV oil immersed transformer has standardized and controllable daily maintenance work. Operators need to regularly inspect the oil tank sealing welds and flange connections to eliminate potential oil leakage risks. Check the insulating oil level, oil clarity and dielectric strength regularly, and replace aging deteriorated insulating oil in a timely manner. Clean the surface of cooling radiators to ensure unobstructed heat dissipation and avoid overheating faults under heavy load. Periodically test winding insulation resistance, operating temperature and three-phase voltage balance. Strictly prohibit long-term overload operation. With standardized routine maintenance, the equipment service life can steadily exceed 25 years.