Mitigation of Electric Arc Furnace Transformer Inrush Current Using Soft-Starter-Based Controlled Energization

The energization of power transformers is a frequent operation in Electric Arc Furnaces (EAF). Magnetization inrush currents with 10 to 50 times the rated transformer current can flow during several line cycles. The magnitude of the inrush currents depends on parameters like the point on wave of voltage energization, residual flux in the core, transformer size and utility systems characteristics. This momentary high current results in system disturbances and reduction of the transformer life cycle. In this paper a scheme to mitigate the inrush current using controlled voltage ramp soft-starter-based circuit is presented. Simulation and experimental results prove the effectiveness of the soft-starter-based controlled energization.

[1]  Wilsun Xu,et al.  A Sequential Phase Energization Method for Transformer Inrush Current Reduction—Transient Performance and Practical Considerations , 2007, IEEE Transactions on Power Delivery.

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

[3]  Ewald F. Fuchs,et al.  Influence of harmonics on power distribution system protection , 1988 .

[4]  K. J. Frohlich,et al.  Elimination of transformer inrush currents by controlled switching. I. Theoretical considerations , 2001 .

[5]  Ryan A Turner,et al.  Transformer Inrush Currents , 2010, IEEE Industry Applications Magazine.

[6]  Fredrik Carlsson,et al.  Ride-through investigations for a hot rolling mill process , 2000, PowerCon 2000. 2000 International Conference on Power System Technology. Proceedings (Cat. No.00EX409).

[7]  N. Fischer,et al.  Single-Phase Transformer Inrush Current Reduction Using Prefluxing , 2012, IEEE Transactions on Power Delivery.

[8]  Sidelmo M. Silva,et al.  Protecting Control Panels Against Voltage Sags: Using a Square-Wave Series Voltage Compensator , 2014, IEEE Industry Applications Magazine.

[9]  Hengxin He,et al.  Harmonic measurements and analysis in a modern steel manufacturing facility , 2010, IEEE PES General Meeting.

[10]  Jeffrey A. Baron,et al.  Design, Analysis and Operation of the Electrical Distribution System for a Modern Electric Arc Furnace and Ladle Melt Furnace , 2009, 2009 IEEE Industry Applications Society Annual Meeting.

[11]  M. P. Bhawalkar,et al.  Use of power electronic converters to suppress transformer inrush current , 2012, 2012 IEEE International Conference on Power Electronics, Drives and Energy Systems (PEDES).

[12]  Fredrik Carlsson,et al.  On impacts and ride-through of voltage sags exposing line-operated AC-machines and metal processes , 2003 .

[13]  Jose C. de Oliveira,et al.  A controlled switching methodology for transformer inrush current elimination: Theory and experimental validation , 2011, 11th International Conference on Electrical Power Quality and Utilisation.

[14]  C.H. Kim,et al.  The analysis of power quality effects from the transformer inrush current: A case study of the Jeju power system, Korea , 2008, 2008 IEEE Power and Energy Society General Meeting - Conversion and Delivery of Electrical Energy in the 21st Century.

[15]  Yu Cui,et al.  A sequential phase energization technique for transformer inrush current reduction - Part I: Simulation and experimental results , 2005 .

[16]  N Chiesa,et al.  Novel Approach for Reducing Transformer Inrush Currents: Laboratory Measurements, Analytical Interpretation and Simulation Studies , 2010, IEEE Transactions on Power Delivery.

[17]  Mohammad Mirzaie,et al.  Calculation and Analysis of Transformer Inrush Current Based on Parameters of Transformer and Operating Conditions , 2011 .

[18]  W. Xu,et al.  A sequential phase energization technique for transformer inrush current reduction - Part II: theoretical analysis and design guide , 2004, IEEE Transactions on Power Delivery.