Towards a transformer transient model as a lumped-distributed parameter system

• Sergey E. Zirka ^[1] ; Yuriy I. Moroz ^[1] ; Ebrahim Rahimpour ^[2]
  1. [1] Dnipro National University
  2. [2] ABB AG
• Localización: Compel: International journal for computation and mathematics in electrical and electronic engineering, ISSN 0332-1649, Vol. 36, Nº 3 (Special Issue: EPNC 2016), 2017, págs. 741-750
• Idioma: inglés
• Enlaces
  • Texto completo
• Resumen

  • Purpose – The purpose of this study is to develop a topological model of a three-phase, three-limb transformer for low-frequency transients. The processes in the core limbs and yokes are reproduced individually by means of a dynamic hysteresis model (DHM). A method of accounting for the transformer tank with vertical magnetic shunts at the tank walls is proposed and tested on a 120 MVA power transformer.

    Design/methodology/approach – The model proposed has been implemented independently in a dedicated Fortran program and in the graphical pre-processor ATPDraw to the ATP version of the electromagnetic transient program.

    Findings – It was found that the loss prediction in a wide range of terminal voltages can only be achieved using a DHM with variable excess field component. The zero sequence properties of the transformer can be accurately reproduced by a duality-derived model with Cauer circuits representing tank wall sections (belts).

    Research limitations/implications – In its present form, the model proposed is suitable for lowfrequency studies. Its usage in the case when transformer capacitances are involved should be studied additionally.

    Practical/implications – The presented model can be used either as an independent tool or serve as a reference for subsequent simplifications.

    Social/implications – The model proposed is aimed at meeting the needs of electrical engineering and ecology-minded customers.

    Originality/value – Till date, there were no experimental data on zero-sequence behavior of three-phase, three-limb transformer with vertical magnetic shunts, so no verified transient model existed. The model proposed is probably the first that matched this behavior and reproduced measured no-load losses for a wide voltage range.