Application of Wavelet Packet and S Transforms for Differential Protection of Power Transformer

Waad Noori Taboor; Adel Ahmed Obed; Majed Abdul Nabi Alwan

doi:10.31026/j.eng.2013.02.08

Article Details

Application of Wavelet Packet and S Transforms for Differential Protection of Power Transformer

Authors:

Waad Noori Taboor | Adel Ahmed Obed | Majed Abdul Nabi Alwan

Publisher:

University of Baghdad

Journal:

Journal of Engineering Vol.19 Issue 2, pp.264-279

Document Type:

Article

Publication Date:

1/2013

Document Language:

English

Document ID (Org No.):

2001380613

pISSN:

2520-3339

DOI:

10.31026/j.eng.2013.02.08

Keywords:

Abstract:

 The differential protection of power transformers appears to be more difficult than any type of protection for any other part or element in a power system. Such difficulties arise from the existence of the magnetizing inrush phenomenon. Therefore, it is necessary to recognize between inrush current and the current arise from internal faults. In this paper, two approaches based on wavelet packet transform (WPT) and S-transform (ST) are applied to recognize different types of currents following in the transformer. In WPT approach, the selection of optimal mother wavelet and the optimal number of resolution is carried out using minimum description length (MDL) criteria before taking the decision for the extraction features from the WPT tree. In ST approach,the spectral energy index and the standard deviation (STD) are calculated from the S-matrix obtained by discrete S-transform. The two approaches are tested for generating a trip signal and disconnecting the transformer supply experimentally using 1KVA, 220/110V, 50Hz, ∆ / Y threephase transformer. The experimental results show that the trip signal is initiated faster in WPT approach while the transformer is disconnected from the supply after a delay of 10-15msec in thetwo approaches due to computer interface and the relay circuit used.

Article Details

Application of Wavelet Packet and S Transforms for Differential Protection of Power Transformer

Authors:

Waad Noori Taboor | Adel Ahmed Obed | Majed Abdul Nabi Alwan

Publisher:

University of Baghdad

Journal:

Journal of Engineering Vol.19 Issue 2, pp.264-279

Document Type:

Article

Publication Date:

1/2013

Document Language:

English

Document ID (Org No.):

2001380613

pISSN:

2520-3339

DOI:

10.31026/j.eng.2013.02.08

differential protection

wavelet packet transform

S-transform

inrush and fault Currents recognition

Issues

Article Details

Application of Wavelet Packet and S Transforms for Differential Protection of Power Transformer

Authors: Waad Noori Taboor | Adel Ahmed Obed | Majed Abdul Nabi Alwan

Publisher: University of Baghdad

Journal: Journal of Engineering Vol.19 Issue 2, pp.264-279

Document Type: Article

Publication Date: 1/2013

Document Language: English

Document ID (Org No.): 2001380613

pISSN: 2520-3339

DOI: 10.31026/j.eng.2013.02.08

differential protection

wavelet packet transform

S-transform

inrush and fault Currents recognition

Issues

Authors:

Waad Noori Taboor | Adel Ahmed Obed | Majed Abdul Nabi Alwan

Publisher:

University of Baghdad

Journal:

Journal of Engineering Vol.19 Issue 2, pp.264-279

Document Type:

Article

Publication Date:

1/2013

Document Language:

English

Document ID (Org No.):

2001380613

pISSN:

2520-3339

DOI:

10.31026/j.eng.2013.02.08