DFA Case Studies
Pickwick Electric Cooperative (PEC, Selmer, TN) used DFA technology to avoid an impending outage from tree encroachment in an overhead line. The DFA system discovered the problem, based solely on substation-based current and voltage waveforms, coupled with intelligent, on-line algorithms. It provided location information that enabled PEC to find and eliminate the encroachment before it caused a permanent outage. PEC had no other indication that a problem existed.
Cracked and burned bushings and insulators are well-known causes of interruptions and outages. DFA technology enables utilities to avert sustained outages resulting from apparatus failures, including compromised bushings. By applying intelligent, on-line algorithms to substation-based current and voltage waveforms, the DFA system detects electrical precursors and alerts utilities of developing problems. In the case of the burned bushing shown below, the utility used the DFA to discover the problem existed, locate the burned bushing, and make repairs that preempted a likely future outage. At no point did the utility receive any customer complaints related to this issue; the DFA system provided their first and only notice.