According to statistics, the transmission and distribution losses account for about 6.6% of the country's electricity generation, and distribution transformer losses account for 40-50%. It is equivalent to 2 times that of the Three Gorges power station in 2017.The power loss is very serious.

In response to the national energy-saving policy and to promote efficient and energy-saving of distribution transformers, Baosteel has already focused on low iron loss oriented silicon steel, especially the research and development of new products, commercial manufacture and user technology of 0.18mm and 0.20mm thin-gauge low iron loss grain-oriented silicon steel.

The iron loss performance of oriented silicon steel is the key index to decide the loss value of transformer. Theoretically, with the thickness of silicon steel thinning, the iron loss value of materials will gradually reduce; but the difficulty of product manufacturing will multiply, the difficulty of magnetic properties stability control is geometrically multiplied. The low iron loss series oriented silicon steels for high energy efficiency transformers are manufactured by using advanced technologies such as composition control and strip heat treatment developed independently to ensure the stability and controllability of magnetic properties.

■ B30R090，P17/50≤0.88w/kg，B8≥1.91T；

■ B27R080，P17/50≤0.78w/kg，B8≥1.91T；

■ B23R075，P17/50≤0.74w/kg，B8≥1.91T；

■ B20R070，P17/50≤0.68w/kg，B8≥1.91T；

■ B20R065，P17/50≤0.64w/kg，B8≥1.91T；

■ B18R065，P17/50≤0.64w/kg，B8≥1.91T；

With the demand of energy and the sensitivity of noise is increase , The users have more stringent requirements for transformer performance, especially noise performance. Beginning in 2015, the State Grid's bidding standards for power transformers require noise reduction of 5 db on the basis of the original standards.

In response to the national noise reduction policy, Baosteel has actively developed low noise grain-oriented silicon steel ，which have the advantages of keeping magnetic properties unchanged and reducing noise characteristics by 3 to 4 dB.

The magnetostrictive property of grain-oriented silicon steel is the main factor determining the noise of transformer body. The magnetostrictive properties are mainly determined by the number of 90°domains. If the 90° domains are reduced, the magnetostriction will decrease also. However, due to the large number of interaction factors and the interaction of magnetic domains, the manufacture of products is very difficult. The low noise oriented silicon steel of Baosteel adopts dozens of advanced technologies developed independently and integratively by Baosteel in the manufacturing process, which ensures the controllability of the production process and the stability and excellent performance of the products. At present, Baosteel has the ability of supplying low noise oriented silicon steel contains two specifications of four brands: B30P105-LM, B30P120-LM, B27P100-LM, B27R095-LM;

1. Background:

With the stringent national energy-saving requirement is increse, some ending users (such as the Southern Power Grid) need to use more energy-saving distribution transformer. For example, the most stringent national standard is the first-class energy efficiency standard distribution transformer.

According to GB20052-2013 standard, the distribution transformer that meets the first-class energy efficiency requirement is defined as energy-saving distribution transformer.