International Journal of Power and Energy Research

Download PDF (458.2 KB) PP. 53 - 62 Pub. Date: April 25, 2017

DOI: 10.22606/ijper.2017.11005

• Mohamed M. Saied^*
  Professor (Emeritus), Independent Researcher, Giza, Cairo, Egypt

A procedure and a corresponding computer program for determining the transient response of a transformer winding under faulty conditions are presented. The model is based on distributed-parameter analysis and is capable of taking the non-uniform distributions of the winding’s inductances and capacitances into account. It will be demonstrated that snapshots of the instantaneous voltage and current distributions along the winding at any point in time, as well as the energization response to standard input stimuli can be efficiently utilized for monitoring the winding’s conditions. An auxiliary function is suggested for simulating the different kinds, severities and locations of the internal faults. Results for both solidly-earthed and isolated transformer neutral points are given. It will be indicated that the source current includes useful information for assessing the winding’s integrity and recognizing the type and location of eventually existing faults. It is believed that the presented approach can assist in providing helpful database for the condition monitoring of power transformers.

Distributed parameter circuits, condition monitoring, electromagnetic transients, faults, frequency response, integrity, modeling, mutual parameters, non-uniform, power transformers, transient response, winding

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