Technical Seminar

Prof. Robert Hebner, UT Center for Electromechanics

"Physics of Failure in Power System Apparatus"

12:00pm, RLM 11.204

Abstract: In the US, many components of the electric grid have exceeded their design life, but the term "design life" is a misnomer. When the polymeric materials were added to the system, there was reason to believe they were long lasting, but there was not information as to how long lasting. With the financial constraints on the utilities, the aging of the infrastructure, and the fact that companies that made the systems have largely exited from the business, it is becoming critically important to the electric utilities that they understand the physics of failure.

Electric cables make an interesting focus for this discussion, as they are in the news today, having forced the temporary closure of the subway system in Washington, DC. The ultimate failure of cables is nearly electrical, but aging is a complex electrical, mechanical, chemical, and thermal process, and there is no a priori reason to assume these variables are independent. While there is not yet a reliable physics-based equation predicting lifetime, the progress in identifying and quantifying the roles of some factors and the characterization of them on the level of electron behavior is summarized.