Types of Single-Phase Transformer

Single-phase transformers are essential electrical devices widely used in power distribution, industrial control, and residential systems. Based on insulation type, functionality, and core design, these transformers can be classified into several categories. This article introduces the main types of single-phase transformers and their typical applications.

1. By Insulation Medium: Dry-Type vs Oil-Immersed

Dry-Type Transformer

Dry-type transformers use air as the insulation and cooling medium. They are fire-resistant and suitable for indoor installations in hospitals, commercial buildings, and public institutions. They require less maintenance and are considered environmentally friendly.

Oil-Immersed Transformer

These transformers use insulating oil for cooling and insulation, offering better thermal performance. They are typically used outdoors in power systems with higher capacity. Regular maintenance is needed, and installation must consider oil containment and fire safety.

2. By Function: Autotransformer vs Isolation Transformer

Autotransformer

An autotransformer shares part of the winding between the input and output, making it smaller, cheaper, and more efficient. However, it offers limited electrical isolation, making it unsuitable for sensitive or isolated systems.

Isolation Transformer

This type of transformer has fully separated primary and secondary windings, providing excellent electrical isolation. It is widely used in medical equipment, laboratory instruments, and systems requiring safety isolation.

3. By Core Construction

Core-Type

In core-type transformers, windings surround the magnetic core. They are common in industry due to their compact design and efficient heat dissipation.

Shell-Type

Shell-type transformers enclose the windings within the core, offering superior electromagnetic stability. These are ideal for precision devices and laboratory applications.

4. Typical Applications

• Voltage regulation in household appliances (e.g., air conditioners, refrigerators)

• Power supply for industrial machinery

• Rural power distribution

• Electrical isolation in medical and sensitive equipment

5. How to Choose the Right Type?

When selecting a single-phase transformer, consider:

• Rated capacity and voltage requirements

• Installation environment (indoor/outdoor)

• Need for electrical isolation

• Cost and maintenance expectations

About WishPower

WishPower is a professional manufacturer of high-quality transformers, offering a full range of single-phase and three-phase models including dry-type, oil-immersed, isolation, and autotransformers. Our products are exported globally and widely used in power utilities, construction, and industrial sectors. We focus on quality, customization, and excellent after-sales support.