电力变压器用磁畴细化高磁感取向硅钢产品差异研究

Research on product differentiation of high magnetic induction grain-oriented silicon steel for power transformer

取向硅钢作为电力变压器的关键核心材料，其磁性能水平直接影响变压器铁心的体积、损耗、噪声及安全裕度。检测了国内外4家磁畴细化高磁感取向硅钢生产厂家同等规格27QG90牌号产品的磁性能，结果表明，国内产品的磁感B。低于国外产品0．01～0．02T，铁损P1.7/50高于后者0．02～0．04W／kg。采用磁畴观测、XRD及EBSD技术从磁畴结构、宏观织构及微观取向三方面分析了导致上述差异的原因。同等规格进口硅钢片中180°磁畴宽度窄，排列更加有序；国外产品中织构组分更单一，高斯取向密度更大，国内成品板中存在一定强度的对磁性能不利的{110}〈112〉黄铜织构；对于直接决定取向硅钢磁感高低的高斯晶粒取向度，国内产品低于进口材料1％～3％。

Grain-oriented silicon steel is the key material for power transformer, and its magnetic proper- ties directly affect the volume, core loss, noise level, and safety margin of transformer core. Magnetic properties of the samples （M90-27P5, IEC standard） from 4 different electrical steel manufacturers at home and abroad were tested. Results show that the magnetic induction of domestic grain-oriented silicon steels is about 0.01 -0.02 T lower than that of foreign products, while the core loss of domestic materials is higher than that of latter ones by 0.02 - 0.04 W/kg. The reasons for the performance disparity were studied by magnetic domains observation, XRD, and EBSD technology/techniques. Compared with do- mestic silicon steels, the imported materials not only have a narrower magnetic domain of 180°, but also own more simplex texture component. Besides, there exists a certain intensity of {110} 〈 112 〉 texture which goes against magnetic performance in domestic samples. The orientation degree of Goss grain, which has a direct influence on magnetic induction, in domestic materials is 1% -3% lower than that in foreign products