Thursday: Afternoon Technical Seminars

1:15 PM
Partial Discharge Testing of Electrical Equipment: Implementing Existing Technologies and Methods

Speakers: Thomas Sandri, Shermco Industries

Details coming soon.

1:15 PM
Primer on Transformer Diagnostic Testing

Speakers: Brandon Dupuis and Charles Sweetser, OMICRON electronics Corp. USA

Transformers are the largest, most expensive, and highly critical components of most utility substations.  In order to ensure a long, useful service life, it is critical that a power transformer and its ancillary components are tested regularly for incipient fault modes. This seminar focuses on how diagnostic techniques can be applied to power transformers as part of the standard condition assessment protocol. The audience will be provided with an understanding, application, and analysis of these tests, supported by specially selected case studies validating the value that these diagnostic tests bring to testing, and finally assessing, power transformers. These specific diagnostic tests have been selected as the primary focus for this seminar and discussion.

  • Power Factor
  • Exciting Current
  • Turns/Voltage Ratio
  • Leakage Reactance
  • SFRA
  • DC Winding Resistance
  • Demag

1:15 PM
Understanding Transformer Protection

Speakers: Scott Cooper, OMICRON electronics Corp USA

Transformer differential protection schemes are ubiquitous to almost any power system. While the basic premise of transformer differential protection is straightforward, numerous features are employed to compensate for challenges presented by the transformer application.

•Current mismatch caused by the transformation ratio
•Current mismatch caused by differing CT ratios
•Delta-wye transformation of currents
•Zero sequence elimination
•LTC induced mismatch, CT saturation, CT remanence, and CT tolerance
•Inrush phenomena and Harmonic content availability
•Over excitation phenomena
•Switch onto fault concerns

These challenges combine to make transformer protection one of the most sophisticated relay systems to test. This paper will explain each of these challenges one at a time, in a technician friendly format.