Research On Transformer Inrush Current And Suppression Technology

As the scale of the power grid expands,the transformer,as a key equipment for power conversion,plays an important role in ensuring the safety and stability of the power grid.When the transformer magnetizing inrush current through the differential protection circuit,it is easy to cause the differential protection to malfunction and reduce the reliability of the power grid system.Therefore,this paper makes an in-depth exploration of the discrimination and suppression technology of magnetizing inrush current.The PSCAD software is used to verify the proposed suppression measures,and the excitation inrush suppressor is successfully put into operation at the substation site.The paper has important theoretical reference and practical application value on inrush current suppression and improve transformer reliability.In this paper,the causes of magnetizing inrush current are deeply analyzed,and the characteristics of magnetizing inrush current are further analyzed.The relationship between magnetizing inrush current and differential protection is discussed,which provides a theoretical basis for the discrimination of magnetizing inrush current and its containment.The different identification methods and suppression schemes of magnetizing inrush current are compared and analyzed,and the surge suppression scheme and its effectiveness are analyzed mostly,providing theoretical test support for the suppression scheme proposed in this paper.Then the relationship between the transformer closing angle,residual magnetism and magnetizing inrush current is studied respectively.The classical phase-selection closing technique is used to suppress the magnetizing inrush current.Using PSCAD to analyze the suppression of magnetizing inrush current when using different phase-selection closing strategies in the presence or absence of manual degaussing:when there is no degaussing and the transformer has residual magnetism,the synchronous closing strategy has a good suppression effect on the inrush current.When manual degaussing is used and the transformer has no residual magnetism,the fast closing strategy has a good inhibitory effect on the magnetizing inrush current.Finally,the magnetization inrush current is suppressed by the phase selection and closure technique based on artificial neural network,and the application of the artificial neural network scheme further improves the suppression effect.Finally,select Xintai power grid which magnetizing inrush current is easy to take place to test inrush suppressor.The data analysis shows that the inrush suppressor adopted has a significant inhibitory effect on the magnetizing inrush current,enhancing the reliability of relay protection and ensuring reliable and stable operation of the power system.The research technology of this paper are further improved on the basis of the original research scheme,which can provide a better solution for the identification and containment of transformer magnetizing inrush current in actual operation.