An Identification Method for Sympathetic Inrush Based on Substation-Area Information

Sympathetic inrush is a phenomenon that occurs in an in-service transformer (IT) when a nearby transformer is energized. The phenomenon can cause transformer differential protection to maloperate. Identification methods for sympathetic inrush have been proposed to deal with the problem. However, these methods are based on local information from the IT, while sympathetic inrush involves two or more transformers. Therefore, an identification method is proposed based on substation-area information. A substation-area differential current is defined and its second harmonic component is utilized to identify the sympathetic inrush. Simulation results by PSCAD/EMTDC show the proposed method can distinguish sympathetic inrush from internal faults and energization inrush effectively.

[2]  S. F. Huang,et al.  A New Algorithm to Avoid Maloperation of Transformer Differential Protection in Substations With an Inner Bridge Connection , 2012, IEEE Transactions on Power Delivery.

[3]  M. Steurer,et al.  The Impact of Inrush Currents on the Mechanical Stress of High-Voltage Power Transformer Coils , 2001, IEEE Power Engineering Review.

[4]  Xj Electric,et al.  Analysis on Mal-operation of Differential Protection Caused by Sympathetic Inrush , 2007 .

[5]  P. Heretík,et al.  Analytical analysis of transformer interaction caused by inrush current , 2014, Proceedings of the 2014 15th International Scientific Conference on Electric Power Engineering (EPE).

[6]  Ge Baoming.  Sympathetic Inrush Identification for Traction Transformer Based on Time Differential Method , 2012 .

[7]  Qinghua Wu,et al.  Using mathematical morphology to discriminate between internal fault and inrush current of transformers , 2016 .

[8]  C. D. Hayward.  Prolonged Inrush Currents With Parallel Transformers Affect Differential Relaying , 1941, Transactions of the American Institute of Electrical Engineers.

[9]  Randy Hamilton,et al.  Analysis of transformer inrush current and comparison of harmonic restraint methods in transformer protection , 2012, 2012 Petroleum and Chemical Industry Conference (PCIC).

[10]  Zhe Zhang,et al.  Study on the Unusual Misoperation of Differential Protection During Transformer Energization and its Countermeasure , 2016, IEEE Transactions on Power Delivery.

[11]  Rafael Mihalic,et al.  Sympathetic inrush current phenomenon with loaded transformers , 2016 .

[12]  R. Yacamini,et al.  Phenomenon of sympathetic interaction between transformers caused by inrush transients , 1995 .

[13]  You Dahai,et al.  Reason of Differential Protection Mal-operation Caused by Complex Sympathetic Inrush and Its Countermeasure , 2011 .

[14]  Jing Ma,et al.  Identifying Transformer Inrush Current Based on Normalized Grille Curve , 2011, IEEE Transactions on Power Delivery.

[15]  Zheng Tao,et al.  Study on a Mal-opertaion case of differential protection due to the interaction between magnetizing inrush and sympathetic inrush , 2014, 2014 IEEE PES General Meeting | Conference & Exposition.

[16]  R. Yacamini,et al.  Harmonic analysis of transient currents during sympathetic interaction , 1996 .