1. Product Overview

ZISHENG 25000kVA Oil-Immersed Copper Transformer for Substation is a high-capacity power transformer designed for large-scale power transmission and distribution systems, industrial substations, renewable energy projects, and utility power networks.

With a rated capacity of 25MVA (25000kVA), this transformer is engineered to provide reliable voltage conversion, high power transmission capability, and stable operation for demanding electrical applications.

The transformer adopts high-quality copper windings and transformer oil insulation and cooling technology. The oil-immersed structure provides excellent heat dissipation, strong insulation performance, and reliable operation under continuous heavy loads.

Manufactured with advanced transformer technology, premium electrical materials, and strict quality control procedures, ZISHENG 25000kVA Oil-Immersed Copper Transformer offers:

• High power capacity
• High energy efficiency
• Low transmission losses
• Excellent thermal performance
• Superior short-circuit withstand capability
• Reliable operation under demanding conditions
• Long service life

It is widely applied in:

• Utility substations
• Industrial power plants
• Renewable energy power stations
• Mining and metallurgy projects
• Large infrastructure projects
• Regional power transmission systems

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2. Product Specifications

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3. Main Structure Design

3.1 High-Efficiency Silicon Steel Core

The 25000kVA transformer uses advanced grain-oriented silicon steel core technology.

Features:

• Low magnetic loss
• High magnetic permeability
• Reduced excitation current
• Lower operating temperature
• Improved energy efficiency
• Reduced operating noise

The optimized core design minimizes energy losses during continuous high-power operation and improves overall transformer efficiency.

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3.2 Premium Copper Winding System

The transformer adopts high-conductivity copper windings designed for large-capacity power transmission applications.

Advantages of Copper Windings:

• Excellent electrical conductivity
• Lower resistance loss
• Superior thermal performance
• Strong mechanical strength
• Excellent short-circuit resistance
• Long operational lifespan

The copper winding structure improves transformer efficiency and ensures stable performance under heavy load conditions.

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3.3 Advanced Oil Cooling and Insulation System

The transformer uses high-quality transformer oil as both cooling and insulation medium.

Main Functions:

• Transfers heat generated by core and windings
• Provides electrical insulation
• Improves overload capability
• Maintains stable operating temperature
• Extends insulation system lifespan

For higher capacity applications, optional cooling methods include:

• ONAN (Oil Natural Air Natural)
• ONAF (Oil Natural Air Forced)

These cooling systems ensure reliable operation under continuous high-load conditions.

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3.4 Heavy-Duty Transformer Tank Structure

The transformer tank is designed for large-capacity substation applications.

Features:

• High mechanical strength
• Excellent sealing performance
• Strong oil leakage prevention
• Outdoor weather resistance
• Long-term structural reliability

The robust tank design enables operation in:

• High-temperature regions
• Tropical climates
• Industrial environments
• Outdoor substations

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3.5 Advanced Voltage Regulation System

The transformer can be equipped with:

• Off-circuit tap changer
• On-load tap changer (OLTC)

Benefits:

• Stable output voltage
• Improved power quality
• Flexible grid operation
• Adaptation to voltage fluctuations

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4. Product Advantages

High Power Transmission Capability

The 25000kVA transformer is designed for large-scale power systems requiring high capacity and stable operation.

Suitable for:

• Power generation plants
• Grid substations
• Industrial power networks
• Renewable energy stations

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Excellent Energy Efficiency

The transformer adopts advanced low-loss materials and optimized electromagnetic design.

Benefits:

• Reduced no-load loss
• Reduced load loss
• Lower operating costs
• Improved energy utilization

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Superior Short-Circuit Resistance

The reinforced copper winding structure and mechanical design provide excellent resistance against short-circuit forces.

Advantages:

• Improved system safety
• Reduced equipment failure risk
• Enhanced operational reliability

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Strong Overload Capability

The efficient cooling system and robust internal structure allow the transformer to withstand temporary overload conditions.

Suitable for:

• Industrial peak loads
• Grid load variations
• Renewable energy fluctuations

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Reliable Long-Term Operation

The combination of:

• High-quality copper windings
• Premium insulation materials
• Advanced manufacturing technology
• Strict quality control

ensures long service life and stable performance.

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5. Application Areas

Power Grid Substations

• High-voltage substations
• Transmission networks
• Regional power distribution systems

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Industrial Power Systems

• Steel plants
• Mining operations
• Chemical plants
• Manufacturing facilities
• Large industrial parks

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Renewable Energy Projects

• Large-scale solar power plants
• Wind farms
• Energy storage facilities

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Infrastructure Projects

• Railways
• Airports
• Ports
• Urban power networks

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6. Technical Features

High Reliability Design

Designed for continuous operation with:

• Strong insulation system
• Reinforced mechanical structure
• Advanced cooling system
• High-quality electrical components

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Outdoor Installation Capability

The transformer is suitable for outdoor substations with:

• Weather-resistant design
• Anti-corrosion treatment
• Reliable sealing structure
• Strong environmental adaptability

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Low Maintenance Requirement

Recommended maintenance includes:

• Transformer oil testing
• Oil level inspection
• Bushing inspection
• Cooling system checking
• Insulation performance testing
• Protection device inspection

Regular maintenance improves transformer reliability and service life.

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Flexible Customization Options

ZISHENG provides customized solutions according to project requirements.

Available options:

• Voltage ratio
• Frequency (50Hz/60Hz)
• Copper winding specification
• Vector group
• Impedance value
• Cooling method
• Tap changer type
• Protection system
• Special environmental design

Optional accessories:

• Oil temperature indicator
• Oil level indicator
• Pressure relief device
• Buchholz relay
• Lightning arrester
• Cooling fans
• Monitoring system

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7. Manufacturing Process and Quality Control

ZISHENG applies strict quality management throughout the complete manufacturing process.

Raw Material Inspection

Including:

• Copper conductor inspection
• Silicon steel core inspection
• Insulation material inspection
• Transformer oil quality testing

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Production Process

Including:

• Core manufacturing
• Copper winding production
• Insulation assembly
• Transformer body assembly
• Tank fabrication
• Vacuum drying
• Vacuum oil filling

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Final Factory Testing

Each 25000kVA transformer undergoes comprehensive testing:

• Winding resistance test
• Insulation resistance test
• Transformer ratio test
• No-load loss test
• Load loss test
• Dielectric strength test
• Temperature rise test
• Oil leakage test
• Short-circuit withstand verification
• Protection system testing

Only qualified transformers are approved for delivery.

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8. Why Choose ZISHENG 25000kVA Oil-Immersed Copper Transformer

• Professional transformer manufacturer
• Advanced manufacturing technology
• High-capacity transformer production capability
• Premium copper winding materials
• Strict quality control system
• Customized engineering solutions
• Stable production capacity
• Reliable delivery capability
• International export experience

ZISHENG 25000kVA Oil-Immersed Copper Transformer for Substation provides a reliable, efficient, and high-performance power solution for utility companies, EPC contractors, renewable energy developers, industrial enterprises, and large-scale infrastructure projects worldwide.

25000kVA Oil-Immersed Copper Transformer for Substation

Product Q&A

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Q1: What is a 25000kVA Oil-Immersed Copper Transformer?

A: A 25000kVA Oil-Immersed Copper Transformer is a high-capacity power transformer designed for large-scale substations, power transmission systems, industrial facilities, and renewable energy projects.

With a rated capacity of 25MVA, the transformer uses high-quality copper windings and transformer oil as the cooling and insulation medium to provide efficient voltage conversion, stable power transmission, and reliable long-term operation.

It is mainly used in medium and high-voltage power networks where high capacity, high reliability, and excellent electrical performance are required.

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Q2: What are the main advantages of a 25000kVA Copper Transformer?

A: The main advantages include:

• High power transmission capacity
• High efficiency and low energy loss
• Premium copper winding performance
• Excellent heat dissipation
• Strong overload capability
• Superior short-circuit resistance
• Reliable insulation performance
• Long service life
• Stable operation under heavy loads
• Suitable for outdoor substations

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Q3: Where is a 25000kVA Oil-Immersed Transformer commonly used?

A: The transformer is widely used in:

• Utility power substations
• Transmission and distribution networks
• Power generation plants
• Solar photovoltaic power stations
• Wind power projects
• Mining and mineral processing facilities
• Steel plants
• Large industrial factories
• Infrastructure power systems

It is suitable for projects requiring continuous and reliable high-capacity power supply.

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Q4: Why does the 25000kVA transformer use copper windings?

A: Copper windings are selected because copper has excellent electrical and thermal properties.

Advantages include:

• Higher electrical conductivity
• Lower resistance losses
• Better heat dissipation
• Strong mechanical strength
• Excellent short-circuit withstand capability
• Improved transformer efficiency

Copper winding design helps the transformer maintain stable performance during long-term high-load operation.

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Q5: What voltage ratings are available for the 25000kVA transformer?

A: ZISHENG provides customized voltage configurations according to customer project requirements.

Common voltage ratings include:

High Voltage Side:

• 6kV
• 10kV
• 11kV
• 13.8kV
• 20kV
• 35kV
• 66kV
• 110kV

Low Voltage Side:

• 400V
• 415V
• 690V
• Customized voltage levels

The voltage ratio can be designed according to local grid standards and substation requirements.

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Q6: What is the cooling method of the 25000kVA Oil-Immersed Transformer?

A: The standard cooling method is usually:

ONAN (Oil Natural Air Natural)

For higher load requirements, optional cooling methods include:

ONAF (Oil Natural Air Forced)

The cooling system helps:

• Remove heat from windings and core
• Maintain safe operating temperature
• Improve overload capability
• Extend insulation life

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Q7: What is the difference between a 25000kVA Oil-Immersed Transformer and a Dry Type Transformer?

A: The main differences are:

For 25MVA applications, oil-immersed transformers are commonly selected due to their excellent cooling performance and reliability.

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Q8: Can the 25000kVA transformer be customized?

A: Yes. ZISHENG provides customized transformer solutions according to project requirements.

Customization options include:

• Rated voltage
• Frequency (50Hz/60Hz)
• Copper winding design
• Vector group
• Short-circuit impedance
• Cooling method
• Tap changer type
• Protection system
• Tank structure
• Installation requirements

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Q9: What transformer oil is used in the 25000kVA transformer?

A: The transformer uses high-quality insulating oil designed for power transformer applications.

Transformer oil provides:

• Electrical insulation
• Heat transfer
• Cooling performance
• Internal component protection
• Improved transformer lifespan

The oil quality is tested during production to ensure reliable insulation performance.

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Q10: What protection accessories are available?

A: ZISHENG can provide various protection and monitoring accessories, including:

• Buchholz relay
• Oil temperature indicator
• Oil level indicator
• Pressure relief device
• Lightning arrester
• Cooling fans
• Monitoring system
• Online temperature monitoring

These accessories improve operational safety and help operators monitor transformer conditions.

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Q11: Can the 25000kVA transformer operate outdoors?

A: Yes. The transformer is designed for outdoor substation installation.

The outdoor structure provides:

• Weather resistance
• Moisture protection
• Anti-corrosion capability
• Strong mechanical strength
• Reliable oil sealing

It can operate in various environments, including:

• Tropical regions
• High-temperature areas
• Industrial areas
• High-humidity locations

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Q12: What tests are performed before delivery?

A: Each ZISHENG 25000kVA transformer undergoes strict factory testing.

Testing includes:

• Winding resistance test
• Insulation resistance test
• Voltage ratio test
• No-load loss test
• Load loss test
• Dielectric strength test
• Temperature rise test
• Oil leakage test
• Transformer oil quality test
• Protection system inspection

Only qualified transformers are shipped to customers.

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Q13: What standards can the 25000kVA transformer comply with?

A: ZISHENG transformers can be manufactured according to:

• IEC standards
• ANSI standards
• Customer technical specifications
• Local grid requirements

The transformer design can be adapted to different international markets.

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Q14: What maintenance is required for a 25000kVA Oil-Immersed Transformer?

A: Recommended maintenance includes:

• Regular transformer oil testing
• Checking oil level
• Inspecting bushings
• Checking cooling equipment
• Inspecting protection devices
• Testing insulation performance
• Checking grounding system

Proper maintenance helps ensure safe operation and extend transformer service life.

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Q15: What is the service life of a 25000kVA Oil-Immersed Copper Transformer?

A: A high-quality 25000kVA Oil-Immersed Copper Transformer can provide decades of reliable operation when properly installed and maintained.

Service life depends on:

• Operating conditions
• Load level
• Cooling performance
• Environmental conditions
• Maintenance quality
• Insulation condition

ZISHENG uses high-quality materials and strict manufacturing processes to ensure long-term reliability.

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Q16: Why choose ZISHENG 25000kVA Oil-Immersed Copper Transformer?

A: ZISHENG provides:

• Professional transformer manufacturing capability
• Experience in international power projects
• High-quality copper winding technology
• Advanced production equipment
• Strict quality control system
• Customized engineering solutions
• Reliable delivery capability
• Competitive factory-direct pricing

ZISHENG 25000kVA Oil-Immersed Copper Transformer for Substation is a reliable high-capacity power solution for utility companies, EPC contractors, renewable energy developers, industrial enterprises, and large-scale infrastructure projects worldwide.