What are the enameled wires commonly used in oil type transformers?

The low-voltage winding of the oil type transformer generally adopts a cylindrical structure with copper foil wound around the shaft, except for the small capacity using copper wire. The high-voltage winding adopts a multi-layer cylindrical structure to make the ampere-turn distribution of the winding balanced. In this way, the leakage magnetic field is small, the mechanical strength is high, and the short-circuit resistance is strong.

The oil type transformer can solve the problem of large-capacity heat dissipation and high-voltage insulation of the transformer.

The oil type transformer adopts a fully oil-filled sealed type. The corrugated oil tank shell adapts to the expansion of the oil with its own elasticity and is a permanently sealed oil tank. oil type transformers have been widely used in various power distribution equipment. The distribution transformer is an important component of the substation, and the oil type transformer is generally installed in a separate transformer room.

Relying on oil as a cooling medium, such as oil type self-cooling, oil type air cooling, oil type water cooling and forced oil circulation. The main transformers of booster stations are generally oil type, with a ratio of 20KV/500KV or 20KV/220KV. The transformers used by power plants to drive their own loads are also oil type transformers, with a ratio of 20KV/6KV, such as coal mills, induced draft fans, forced draft fans, circulating water pumps, etc.

The transformer immersed in transformer oil has an insulation heat resistance grade of Class A and a long-term working temperature of 105℃. Therefore, oil type transformers generally use polyimide enameled wires with high temperature resistance and good insulation performance.

 

The following is an introduction to the available enameled wires:
1.Polyimide enameled wire
Polyimide enameled wire is an enameled wire with good insulation performance, high temperature resistance, corrosion resistance, arc breakdown resistance and other characteristics. It is widely used in the manufacture of oil type transformers.
Polyimide enameled wire has a large insulation thickness, excellent mechanical properties and heat resistance. It can withstand high pressure and high temperature environments, and is more reliable. The conventional specifications are 180℃, 200℃, 220℃, etc.
2.Polyamide enameled wire
Polyamide enameled wires, also known as polyamide-imide (PAI) coated wires, are widely used in electrical and electronic applications due to their superior mechanical, thermal, and chemical properties. These wires are coated with a layer of polyamide-imide resin, which enhances their performance in various demanding environments.
3.Polyimide amide enameled wire
Polyimide amide enameled wires are a type of magnet wire insulated with a polyimide-imide coating. This type of insulation provides exceptional durability and reliability, making these wires suitable for various high-performance applications. The polyimide-imide resin is applied in multiple layers, offering enhanced insulation and protection.
4.Polyimide ketone enameled wire
Polyimide ketone enameled wire is a type of magnet wire that features a coating of polyimide ketone resin, known for its high-performance attributes. These wires are particularly valued for their exceptional thermal stability, mechanical strength, and chemical resistance.

 

These enameled wires also have good insulation and heat resistance, but are slightly inferior to polyimide enameled wires.
Correct selection of suitable enameled wires is crucial to the working stability of oil type transformers.

 

The following factors should be considered when choosing enameled wire:
1. Working environment: The working environment of oil type transformers is usually under high temperature, high pressure and high humidity. Enameled wire that can adapt to these conditions should be selected.
2. Insulation performance: The insulation performance of enameled wire has an important impact on the safety and stable operation of oil type transformers. Enameled wire with excellent insulation performance should be selected.
3. Durability: The investment cost of oil type transformers is high. Enameled wire with long life should be selected to ensure the long-term stable operation of oil type transformers.

In short, choosing suitable enameled wire can effectively improve the working efficiency and stability of oil type transformers, while also ensuring the safety of equipment. If you have any questions about enameled wire, you can ask us!

 

Product Category		Type List			Wire Range (mm)	UL Certificate
		NEMA Type	JIS Type	IEC Type		ANSI Type	TI(℃)
1	Polyester enameled round copper wire		PEW	QZ-*/130	0.035-1.00
		MW5C		QZ-*/155		MW5C	155
2	Polyurethane enameled copper round wire	MW75C	UEW/QA	QA-*/130	0.035-1.00	MW75C	130
		MW79C		QA-*/155		MW79C	155
		MW82C		QA-*/180		MW82C	180
3	Polyesterimide Nylon Composite Enameled Copper Round Wire	MW80C	UEW/N	QA/N-*/155	0.035-1.00	MW80C	155
		MW83C		QA/N-*/180		MW83C	180
4	Polyester-imide enameled round copper wire	MW30C	EIW	QZY-*/180	0.035-1.00	MW30C	180
5	Self-Solderable Polyester-imide Enameled Round Copper Wire	MW77C	SEIW	QZY-S*/180		MW77C	180
6	Polyester-imide Over Coated with Composite Polyamide-imide	MW35C MW73C	EI/AIW	Q(ZY/XY)-*/200	0.035-1.00	MW35C	200
		MW37C		Q(ZY/XY)-*/220		MW73C
7	Polyamide-imide enameled round copper wire	MW81C	AIW	QXY-*/220	0.035-1.00	MW81C	220