三相変圧器：動作原理、種類、用途、および選定ガイド

Voltage Ratio = Primary Turns / Secondary Turns

For example:

ステップダウントランス

Input:

13.8kV

Output:

480V

The transformer reduces medium voltage electricity to a usable low voltage level for industrial equipment.

Three Phase Transformer Types

Three phase transformers can be classified according to construction, insulation method, cooling system, and application.

1. Three Phase Dry Type Transformer

A three phase dry type transformer uses air as the cooling and insulation medium instead of transformer oil.

Dry type transformers are widely used where fire safety and environmental protection are important.

Advantages of Dry Type Transformer
High fire safety
No oil leakage risk
メンテナンスの手間が少ない
Suitable for indoor installation
Environmentally friendly
一般的な用途

Three phase dry type transformers are commonly installed in:

商業ビル
病院
空港
データセンター
Industrial facilities
ショッピングセンター

代表的な評価：

EverNew manufactures dry type transformers with:

• Copper winding
• Aluminum winding
• Cast resin insulation
• UL/CSA compliant designs

2. Three Phase Oil Immersed Transformer

A three phase oil immersed transformer uses insulating oil for cooling and electrical insulation.

Oil immersed transformers are commonly used for outdoor power distribution because they provide excellent heat dissipation and high capacity capability.

メリット

• High power capacity
• Excellent cooling performance
• 長寿命
• Suitable for outdoor applications

アプリケーション

代表的な用途としては、次のようなものがあります：

• 変電所
• 太陽光発電所
• 風力発電所
• 産業プラント
• Power transmission systems

Typical voltage ratings:

• 6kV
• 10kV
• 11kV
• 13.8kV
• 35kV
• 110kV
• 220kV

3. Three Phase Distribution Transformer

A three phase distribution transformer is designed to reduce medium voltage electricity to low voltage for end users.

Typical conversion:

11kV → 400V

13.8kV → 480V

35kV → 400V

アプリケーション

• Residential areas
• 商業施設
• 工業工場

4. Three Phase Power Transformer

A three phase power transformer is used in high voltage transmission and substations.

アプリケーション

• Power plants
• Grid substations
• 再生可能エネルギー事業

パワーレンジ：

From several MVA to hundreds of MVA.

Three Phase Transformer Applications

産業用電源システム

Factories rely on three phase transformers to supply power for:

• Motors
• Compressors
• Pumps
• CNC machines
• Production lines
• Automation equipment

Industrial transformers usually require:

• High efficiency
• Continuous operation
• Strong overload capability

商業ビル

Three phase transformers are commonly used in:

• Office buildings
• Hotels
• ショッピングモール
• 空港

A common North American system:

480V → 208Y/120V

This voltage system is widely used for:

• Lighting
• HVAC systems
• Building equipment

再生可能エネルギー・プロジェクト

Solar and wind projects require transformers to increase voltage before grid connection.

例

Solar inverter:

800V

↓

Transformer:

0.8kV / 35kV

↓

Grid connection

Three Phase Transformer Voltage Ratings

Different countries use different voltage standards.

北米

Common voltages:

International Markets

Common systems:

EverNew transformers can be designed according to:

• 国際電気標準会議
• べいこくきかくきょうかい
• IEEE
• UL
• 南部連合
• CE
• GOST

How To Select A Three Phase Transformer?

Choosing the correct transformer requires evaluating several technical parameters.

1. Transformer Capacity (kVA)

The transformer capacity must match the electrical load.

Common sizes:

• 15 kVA
• 30 kVA
• 45 kVA
• 75 kVA
• 112.5 kVA
• 150 kVA
• 500 kVA
• 1000 kVA
• 2500 kVA

2. Input and Output Voltage

例

Commercial building:

Input:

480V Three Phase

Output:

208Y/120V Three Phase

3. Frequency

Common frequencies:

• 50Hz
• 60Hz

4. Transformer Cooling Method

Choose according to installation environment:

Indoor:

乾式変圧器

Outdoor:

油浸変圧器

5. Transformer Standards

International projects may require:

• UL certification
• CSA certification
• DOE efficiency
• IEC standards
• IEEE standards

Three Phase Transformer Manufacturer

Selecting a reliable three phase transformer manufacturer is important for ensuring safety, efficiency, and long service life.

A professional transformer supplier should provide:

✔ Engineering design support

✔ Factory testing

✔ International certifications

✔ Customized voltage solutions

✔ Export experience

Why Choose EverNew Transformer?

EverNew Transformer is a professional transformer manufacturer in China with more than 30 years of experience.

Our manufacturing capabilities include:

Product Range

• 配電変圧器
• 乾式変圧器
• 油浸変圧器
• パッド・マウント・トランス
• 電源トランス

Technical Capability

容量：

15 kVA – 500 MVA

電圧：

6kV – 500kV

認証

• UL
• 南部連合
• CE
• GOST
• ISO

We supply transformers for:

• アメリカ
• カナダ
• 南米
• ヨーロッパ
• アジア
• アフリカ

Three Phase Transformer FAQ

What is the difference between single phase and three phase transformer?

A single phase transformer is normally used for smaller loads, while a three phase transformer is designed for industrial and commercial power systems requiring higher capacity.

What is the most common three phase transformer voltage?

Common systems include:

• 480V
• 208Y/120V
• 400V
• 415V
• 13.8kV
• 35kV

How much does a three phase transformer cost?

The price depends on:

• Transformer capacity
• Voltage rating
• Copper or aluminum winding
• 冷却方法
• Required standards
• Order quantity

How do I choose a three phase transformer size?

You should consider:

• Total connected load
• Starting current
• Future expansion
• Voltage requirements
• 効率に関する要件

結論

A three phase transformer is an essential component in modern electrical power systems, providing efficient voltage conversion for industrial, commercial, and renewable energy applications.

Choosing the correct transformer requires careful evaluation of:

• Power capacity
• Voltage levels
• 冷却方法
• Installation environment
• International standards

プロフェッショナルとして three phase transformer manufacturer, EverNew Transformer provides reliable transformer solutions worldwide with customized designs from low voltage distribution systems to high voltage power networks.

Contact EverNew Transformer today for your three phase transformer project.