Method for controlling nitrogen content of high-permeability-grade oriented electrical steel belt

The invention relates to the technical field of steelmaking, in particular to a method for controlling the nitrogen content of a high-permeability-grade oriented electric steel belt. The method particularly includes following steps that molten steel is connected with bottom flushing nitrogen after reaching an RH (relative humidity) refining furnace, and nitrogen flushing treatment is performed for the molten steel; ultimate vacuum treatment is performed at the preliminary stage of RH refining treatment, RH ultimate vacuum degree is smaller than or equal to 200Pa, and nitrogen circulates in anRH vacuum chamber in the whole process; and after the ultimate vacuum treatment is performed for 12 minutes to 15 minutes, RH vacuum degree is reset according to the initial nitrogen content of the molten liquid, RH refining nitrogen adding treatment is performed, and the RH vacuum degree is reduced after a nitrogen adding target value is reached. By means of reasonably controlling nitrogen flow and the RH vacuum degree in an RH refining process, requirements on nitrogen content precision for production of the high-permeability-grade oriented electric steel belt are met. Besides, the method is simple, is high in applicability, and does not affect controlling to purity and H content of the high-permeability-grade oriented electric steel belt.