Induced Voltages Ratio-Based Algorithm for Fault Detection, and Faulted Phase and Winding Identification of aThree-Winding Power Transformer

Energies

Yong Cheol Kang¹  Peter A. Crossley²  Jung-Wook Park³  Byung Eun Lee⁴ 

[1] Department of Electrical Engineering, Wind Energy Grid-Adaptive Technology Research Center, and Smart Grid Research Center, Chonbuk National University, Chonju 561-756, Korea;The School of Electrical and Electronic Engineering, The University of Manchester,Manchester M13 9PL, UK;The School of Electrical and Electronic Engineering, Yonsei University, Seoul 120-749, Korea;Wind Energy Grid-Adaptive Technology Research Center, Chonbuk National University,Chonju 561-756, Korea;

关键词: fault detection;    faulted phase and winding identification;    ratio of induced voltages;    transformer protection;    three-winding transformer;   

DOI  :  10.3390/en7096031

来源: DOAJ

【 摘 要 】

This paper proposes an algorithm for fault detection, faulted phase and winding identification of a three-winding power transformer based on the induced voltages in the electrical power system. The ratio of the induced voltages of the primary-secondary, primary-tertiary and secondary-tertiary windings is the same as the corresponding turns ratio during normal operating conditions, magnetic inrush, and over-excitation. It differs from the turns ratio during an internal fault. For a single phase and a three-phase power transformer with wye-connected windings, the induced voltages of each pair of windings are estimated. For a three-phase power transformer with delta-connected windings, the induced voltage differences are estimated to use the line currents, because the delta winding currents are practically unavailable. Six detectors are suggested for fault detection. An additional three detectors and a rule for faulted phase and winding identification are presented as well. The proposed algorithm can not only detect an internal fault, but also identify the faulted phase and winding of a three-winding power transformer. The various test results with Electromagnetic Transients Program (EMTP)-generated data show that the proposed algorithm successfully discriminates internal faults from normal operating conditions including magnetic inrush and over-excitation. This paper concludes by implementing the algorithm into a prototype relay based on a digital signal processor.

【 授权许可】

Unknown