In general, the purpose of periodic screening with DGA for power transformers is risk assessment. Is any transformer likely to fail in service? If so, how severe is the problem? Previous articles in this series have described ways to improve DGA interpretation. In this article we provide a glimpse of what modern statistics can say about risk assessment, after the previous steps are performed.
Conventional practice with IEEE or IEC guidelines is to compare gas...
The critical importance of power to every aspect of our world cannot be over-exaggerated. It must be generated and distributed effectively to end users, and any disruption in that process means loss of operations, money, and in extreme cases, life. Therefore, the reliability of power creation and...
As a philosophy and English major who has spent the last 20+ years working in the utility industry,I often come across topics that challenge me because I don’t have a science or engineering background. This article is an exploration of the basics around online DGA monitors, to better...
A transformer relies on electromagnetic induction through coils to transfer electric energy between two or more circuits. Varying current in the transformer’s primary winding creates varying magnetic flux in the core, which produces varying electromotive force (EMF) or voltage in the...
There are two standard methods from ASTM International: D877, Standard Test Method for Dielectric Breakdown Voltage of Insulating Liquids Using Disk Electrodes, and D1816, Standard Test Method for Dielectric Breakdown Voltage of Insulating Oils of Petroleum Origin Using VDE Electrodes. VDE stands...
The utilization of online dissolved gas analysis monitoring has proven to be one of the most effective predictors of overall transformer health and condition. A wide range of monitoring systems are available, offering multiple costs, features, and benefit combinations. Hydrogen MonitoringSingle or...
There are two standard methods from ASTM International: D877, Standard Test Method for Dielectric Breakdown Voltage of Insulating Liquids Using Disk Electrodes, and D1816, Standard Test Method for Dielectric Breakdown Voltage of Insulating Oils of Petroleum Origin Using VDE Electrodes. VDE stands...
IntroductionContinuous online monitoring of bushings provides real-time information which can result in the early detection of a possible failure. Challenge: A Major AlarmA prominent U.S. utility was looking for a way to improve system reliability for their 138kV assets. They researched and...
By Chris Rutledge, Product Manager, Dynamic Ratings, Inc. Introduction The utilization of online dissolved gas analysis monitoring has proven to be one of the most effective predictors of overall transformer health and condition. A wide range of monitoring systems are available, offering multiple...
By R.W. Hurst, Editor A distribution transformer is a critical component of the electrical power system, used to reduce the voltage of electrical energy for electric power distribution to end-users. It plays a vital role in voltage regulation and load management, ensuring the efficient and reliable...
By R. W. Hurst, Editor Grounding transformers are used to provide a path to ground for unbalanced load current and for fault currents on systems where a suitable ground is otherwise not available. Grounding transformers are normally constructed with one of the two configurations: Zig-Zag (Zn) with...
