Diagnostic testing of cast resin transformers

April 27, 2018

Because of the flammable nature of the mineral oil used in oil-filled transformers and the risk of oil spillage and ground contamination, cast resin dry-type transformers are alternatively used in locations where fire and environmental safety are important. These include for example buildings, industrial sites and groundwater protection areas.

The most common reason for failures of cast resin transformers is the electric breakdown of the insulation between turns or parts of the windings. In many cases, partial discharges (PD) occur before the breakdown happens and are therefore a measurable indication of a developing problem.

Our paper of the month describes how testing the windings of cast resin transformers with induced voltage in combination with a sensitive PD measurement can minimize the risk of unforeseen outages. Methods for performing these on-site tests with portable equipment are discussed based on case studies.

Enjoy reading and watch out for our paper of the month regularly!

You are using an outdated browser version.
Please upgrade your browser or use another browser to view this page correctly.
×