TITLE:
The Discrimination of Inrush Current from Internal Fault of Power Transformer based on EMD
AUTHORS:
Fanyuan Zeng, Qianjin Liu, Chao Shi
KEYWORDS:
Inrush Current; Transformer Protection; HHT; EMD; IMF
JOURNAL NAME:
Energy and Power Engineering,
Vol.5 No.4B,
November
20,
2013
ABSTRACT: The method is based on that the waveform of the inrush
distorts seriously, while the fault current nearly keeps sinusoid. The
complicated signal can be decomposed into a finite intrinsic mode functions (IMF) by the
EMD, then define and compute the projection area on X-axis of each IMF—, the specific gravity of SIMF—, and the maximum of —. We can get a new scheme of transformer-protection based on
comparing the difference between inrush and fault current. Theoretical analysis
show that the method can precisely discriminate inrush and fault current, fault
clearance time is about 20ms. Moreover, it is convenient to achieve and hardly
be affect by not-periodic component.