Power transformers are the most critical and costly component in electric power transmission and distribution systems. Catastrophic failures of transformers can occur without warning, resulting in serious oil spills, fires, extensive damage to adjacent equipment and major disruption to power service. When the transformer can not be repaired due to the extensive damage, the cost of the failures can be several times the cost of new transformers since the costs for reinstallation, transportation, other equipment damage and/or outages caused by the failure, lost sales revenue, etc., can easily drive the total cost of a single failure into the tens of millions of dollars, Wang explained.
Transformer failures are often caused by dielectric breakdowns that can be triggered by a surge in various chemical gases such as acetylene and hydrogen dissolved in the transformer oil. Dissolved gas detection is thus an important method to learn the health condition of a transformer. The detection is currently handled manually by a process called Dissolved Gas Analysis (DGA) which is a routine procedure in the power industry. However, DGA is an expensive method involving oil sampling, shipping, and laboratory analysis. It often takes days for the measurement results to be obtained. Although DGA can be installed on site and access the transformer oil with a connection port, the cost is still high.
In this project, Virginia Tech will develop a more economical method for on-line dissolved gas detection. The key is that this method does not require oil sampling and provides real-time data about transformer health.
|Contact: Lynn Nystrom|