In recent years, due to the increasing crisis of global warming, the implementation of carbon neutral measures on a global scale has been accelerated, and the requirements for natural energy utilization and energy-saving measures represented by offshore wind power have been strengthened. All countries in the world have made regulations on the efficiency of transformers, an important part of power transmission systems. Strict transformer efficiency regulations such as Japan's toprunner II, the U.S. Department of Energy's (DOE) 2016 regulations, and Europe's EcoDesignDirective II of 2012 are being implemented. It is foreseeable that transformer efficiency regulations will be further tightened in the future. Therefore, the transformer core material oriented electrical steel has been put forward further low iron loss requirements, which means that the demand for ultra-low iron loss of refined magnetic domain oriented electrical steel will be greatly increased. .

The iron loss of electrical steel plate is divided into eddy current iron loss and hysteresis iron loss. Eddy current iron loss is the iron loss caused by the induced current flowing in the transformer core in AC magnetic field. The effective methods to reduce the eddy current iron loss are to reduce the thickness of the electrical steel plate, increase the Si content of the electrical steel plate, improve the inherent resistance of the steel plate, reduce the grain size of the steel plate, and refine the magnetic domain. The effective way to reduce the ferrohysteresis loss is to reduce the impurities in the steel to improve the cleanliness of the steel and to improve the texture strength of the Gauss orientation {110}<001> grains that are easily magnetized in the rolling direction to improve the magnetic induction strength of the electrical steel plate.

Compared with the same level of the plate thickness of 0.20mm, 0.18mm traditional electrical steel plate, the use of 23JGSE070 reduces the number of lamination, the assembled transformer iron loss assembly coefficient BF (building factor) is very low. 23JGSE070 is the material with the lowest iron loss among 0.23mm thick oriented electrical steel plates and is used for transformer laminade cores in areas with strict requirements for transformer efficiency. The JGSE series is characterized by high texture strength with Gaussian orientation and is mainly used for low noise transformers. The use of non-heat-resistant refined magnetic domain oriented electrical steel 23JGSE070 to make transformer core, due to the reduction of iron loss, not only has a significant energy-saving effect, but also can make low noise transformer.