OLTC first lesson illustration

E-lesson: OLTC Course – lesson #1: On-load tap-changer basics

Course: | Free Basic level

In this lesson you will learn the basics of load tap changers, their purpose, various construction types and principle of operation of its patented procedure, resistor and reactor constructions.

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Also, we will present three types of regulation, and try to understand what is written on the OLTC nameplate.

Key takeaways: Tap-changer definitions, OLTC, DETC, principle of operation and patented procedure, resistor and reactor constructions, three types of regulation, understanding the OLTC nameplate

Keywords: tap changers, OLTC, regulation, transformers


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Raka Levi

Electric-power engineer with over 30 years of technical experience in the field of asset management, condition assessment, power instrumentation, diagnostics and monitoring, tap-changer testing, and consulting services. Director of Levico, Inc. a consulting company in the USA.

Over the last nineteen years operated from offices in Boston USA, Belgrade Serbia, Barcelona and Madrid, Spain to provide customized service to clients on all continents. Principle of operations – expert and consultant to multiple companies.

Education: Dr. Sci. in the field of HV computerized condition assessment for circuit breakers at U. of Belgrade, and Master of Engineering in Electrical Power from the Rensselaer Polytechnic Institute, Troy – New York.

Affiliations: Senior Member IEEE (USA), vice-chair of the IEEE working group for revision of IEEE standard C57-152

Raka Levi

Levico, Inc.

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