35kV 10.5kV 10000kVA Oil Immersed Distribution Transformers

35kV 10.5kV 10000kVA  Oil Immersed Distribution Transformers

1. Product Description

35kV 10.5kV 10000kVA Oil Immersed Distribution Transformers are large-capacity industrial-grade three-phase power distribution transformers tailored for 35kV medium-voltage grid systems and heavy-load industrial power supply projects. Belonging to the high-efficiency S13 series low-loss oil-filled transformer lineup, this 10000kVA large-power transformer serves as a core voltage conversion hub that steps down 35kV high medium voltage to standard 10.5kV industrial medium voltage, filling the key link between regional main substations and factory terminal power distribution rooms. Fully compliant with IEC 60076 and GB/T 1094 international power industry standards, this oil immersed distribution transformer undergoes strict factory testing for insulation resistance, load loss, short-circuit withstand capability and voltage regulation accuracy, ensuring stable and reliable long-term full-load operation in commercial grid and heavy industrial scenarios.

Built with high-grade cold-rolled grain-oriented silicon steel core and 100% oxygen-free copper three-phase windings, the 35kV 10.5kV 10000kVA oil immersed transformer effectively suppresses no-load magnetic loss and full-load operating heat generation, delivering superior energy-saving performance compared with traditional old-generation transformers. Adopting a standard YNd11 vector group connection, the equipment maintains precise three-phase voltage and current balance, actively filters grid harmonics, restrains zero-sequence current and eliminates common power quality issues such as load imbalance and voltage drift in heavy-load power grids. Featuring a fully sealed welded corrugated oil tank and mature ONAN oil natural air natural cooling system, the transformer completely isolates internal insulating components from external dust, moisture and corrosive pollutants, preventing insulating oil aging, damp insulation and oil leakage failures. As a mainstream high-capacity 35kV to 10.5kV step-down transformer, it is widely recognized for its large load margin, strong short-circuit resistance and low operational failure rate, ideal for regional grid capacity expansion and heavy industrial centralized power supply.

2. Technical Parameters

3. Core Purpose

The core purpose of 35kV 10.5kV 10000kVA Oil Immersed Distribution Transformers is to provide large-capacity, high-efficiency and stable medium-voltage power conversion and centralized power distribution for 35kV regional power grids and heavy industrial power systems. As a critical backbone power transformation device between 35kV high-voltage transmission lines and 10.5kV industrial distribution networks, this large oil immersed transformer solves the voltage level mismatch problem in bulk power transmission, steadily converting 35kV grid voltage into standardized 10.5kV medium voltage suitable for industrial substation power distribution and secondary voltage conversion.

In daily grid and industrial operation, this 10000kVA three-phase oil filled transformer undertakes multiple key core functions, including regional grid voltage stabilization, large-load power distribution balancing, power harmonic suppression and circuit fault isolation. With super-large 10MVA rated capacity, it effectively meets the continuous heavy-load power demand of large industrial clusters, avoids frequent overload operation of small and medium-capacity transformers, and reduces regional grid transmission loss. It optimizes overall power supply quality of medium-voltage distribution networks, ensures stable and safe bulk power supply for industrial production and regional grid operation, and reserves sufficient load margin for subsequent industrial upgrading and power load growth.

4. Application Scenarios

Benefiting from ultra-large load capacity, ultra-low energy loss, excellent short-circuit resistance and all-weather environmental adaptability, 35kV 10.5kV 10000kVA Oil Immersed Distribution Transformers are widely applied in backbone grid construction, heavy industrial power supply, new energy centralized grid connection and urban grid upgrading projects. It is the preferred core power transformation equipment for large-scale medium-voltage power distribution scenarios:

• Regional 35kV Main Substation Construction: Specially designed for county-level and district-level main substations, undertaking regional bulk power transmission and voltage conversion tasks. It stably supports daily power distribution and peak load regulation of urban and rural regional grids, improving overall power supply capacity and reliability of local power networks.

• Heavy Industrial Cluster Power Supply: Ideal for large metallurgical plants, chemical industrial parks, building materials manufacturing bases and mining industrial zones. The 10000kVA large capacity fully meets long-term continuous heavy-load power consumption demands of heavy industrial equipment and assembly line production, ensuring uninterrupted industrial power supply.

• Large-scale New Energy Grid Connection Projects: Widely matched with centralized photovoltaic power stations, wind power bases and comprehensive energy storage power stations. It completes high-capacity 35kV to 10.5kV voltage conversion, optimizes grid-connected power quality, suppresses new energy power generation harmonics, and realizes safe and efficient bulk grid connection of new energy power.

• Urban Power Grid Capacity Expansion & Renovation: Used for upgrading and capacity expansion of aging urban medium-voltage power grids, replacing outdated high-loss small-capacity transformers. It effectively solves the problem of insufficient regional power supply capacity and grid overload operation, realizing energy-saving and efficient operation of urban power grids.

• Large Infrastructure Supporting Power Projects: Applicable for national key engineering projects, large transportation hubs, industrial demonstration zones and economic development zones. It provides stable large-capacity power guarantee for large-scale public infrastructure and industrial supporting facilities.

• Industrial Park Centralized Power Distribution: Serves as a core power transformation device for large comprehensive industrial parks, uniformly converting 35kV grid voltage to 10.5kV industrial voltage for secondary distribution, realizing centralized management and efficient utilization of park power resources.

5. Product Features

35kV 10.5kV 10000kVA Oil Immersed Distribution Transformers adopt upgraded S13 ultra-low-loss manufacturing technology and heavy-duty oil-immersed cooling structure. Compared with traditional medium and small-capacity transformers and old-generation high-capacity models, this large-power oil immersed distribution transformer has comprehensive advantages in energy-saving efficiency, operational stability, safety protection and load adaptability, fully adapting to long-term full-load heavy-duty operation of 35kV medium-voltage backbone grids:

• Ultra-large Capacity & Strong Load Adaptability: With 10000kVA super-large rated capacity, it perfectly adapts to heavy-load and ultra-heavy-load power distribution scenarios that conventional medium-capacity transformers cannot bear. It stably copes with long-term continuous full-load operation and seasonal peak power surges, with sufficient load margin to support future industrial load growth and grid expansion.

• Ultra-low Loss & High Grid Operation Efficiency: Adopting high-permeability ultra-low loss silicon steel core and high-conductivity pure copper winding structure, it greatly reduces no-load excitation loss and full-load operating loss. All energy efficiency indicators meet national first-class energy efficiency standards, effectively lowering long-term grid transmission energy consumption and industrial power operation costs.

• YNd11 Balanced Power Output & High Power Quality: Standard YNd11 vector group design realizes precise three-phase voltage and current balance, effectively inhibiting zero-sequence current, grid harmonics and voltage deviation. It maintains stable 10.5kV output voltage under unbalanced heavy-load conditions, greatly improving terminal industrial power quality and reducing equipment failure rate.

• Enhanced Short-circuit & Overvoltage Resistance: Internal windings adopt integral reinforcement and anti-short-circuit structural optimization, with strong resistance to short-circuit impact and sudden load shock. The enhanced 35kV high-grade insulation structure and 170kV lightning protection design effectively resist grid overvoltage and lightning surge interference, ensuring safe and stable operation of backbone grid equipment.

• Fully Sealed Maintenance-free Structure: Integral fully welded corrugated oil tank completely isolates internal core, windings and insulating oil from external humid air, dust and corrosive gases. It avoids insulating oil deterioration, insulation damp and oil leakage faults, greatly reducing daily maintenance workload and extending equipment service life.

• Efficient ONAN Cooling & All-weather Adaptability: Mature natural oil circulation and air natural heat dissipation system ensures uniform and efficient heat dissipation, rapidly discharging internal heat generated by long-term full-load operation. The whole machine adopts heavy-duty anti-corrosion electrostatic spraying process, adapting to high temperature, low temperature, rain and wind sand harsh outdoor environments, supporting 24-hour uninterrupted all-weather operation.

6. FAQ (Frequently Asked Questions)

Q1: What are the core advantages of 10000kVA 35kV/10.5kV oil immersed distribution transformers for industrial grid applications?

This 35kV 10.5kV 10000kVA large-capacity oil immersed transformer is professionally optimized for heavy industrial and regional backbone grid scenarios. Different from small and medium-capacity distribution transformers, its 10MVA super-large capacity can meet the long-term full-load operation demands of large industrial clusters without frequent overload tripping. The upgraded low-loss core and copper winding structure significantly reduce grid transmission loss, bringing long-term energy-saving benefits for enterprises and power grids. The YNd11 wiring mode effectively improves industrial power quality, while the fully sealed oil immersed structure adapts to harsh outdoor factory environments, featuring low failure rate and high operational stability, making it the most cost-effective core power transformation equipment for large industrial power distribution.

Q2: Is the off-circuit tap changer of this 35kV 10000kVA transformer suitable for grid voltage fluctuation scenarios?

Absolutely suitable. This large oil immersed distribution transformer is equipped with a standard ±2×2.5% off-circuit tap changer, which can manually adjust the high-voltage tapping position according to actual grid voltage deviation. For regional grids with seasonal voltage fluctuation or long-distance transmission voltage drop, the tap changer can effectively calibrate the input voltage, ensuring the 10.5kV secondary output voltage remains within the standard allowable deviation range. Although it requires power-off adjustment, it features simple operation, stable adjustment accuracy and low failure rate, fully meeting the daily voltage regulation demands of conventional 35kV medium-voltage power grids and industrial substations.

Q3: What key maintenance work is required for a 10000kVA large-capacity oil immersed transformer?

Large-capacity 35kV oil immersed distribution transformers require standardized regular maintenance to ensure long-term stable operation. Daily routine inspection includes checking the oil tank for oil leakage, deformation and corrosion, observing insulating oil level and oil clarity, and monitoring operating noise and temperature rise. Regular maintenance work covers cleaning radiator dust to ensure unobstructed heat dissipation, testing winding insulation resistance and three-phase voltage balance, and fastening high and low voltage wiring terminals. It is necessary to periodically sample and test insulating oil dielectric strength to prevent oil aging and insulation performance degradation. Avoiding long-term overload operation and frequent voltage impact can effectively extend the service life of the transformer, ensuring stable full-load operation for more than 25 years.