Introduction
Dissolved gas analysis (DGA) provides the early warning radar view of a transformer fleet with a non-intrusive screening process for early identification of problematic transformers. Suspicious transformers can be subjected to more invasive and costly physical testing to determine the actual condition and service readiness of the transformer. Three case histories illustrate the usefulness of recent innovations in transformer DGA, especially when there is gas loss. Two of the example transformers failed in service,...
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...
Introduction Fault type identification is an important step in dissolved gas analysis (DGA). When a significant amount fault gas production is detected in a transformer, we want to know what kind of physical condition could be responsible for the gassing. Knowing the type of fault can help to...
As aging transformers at generation facilities near end-of-life cycles, a number of potentially dangerous events can come into play when it comes to aging transformers – in addition to untimely power outages and costly repairs. Because many transformers are exposed to dust and high operating...
ABSTRACTHere we discuss the phenomenon of transformer inrush; what it is and its significance to transformer protection design. INTRODUCTIONA couple of years ago in this Transformer Special Edition, we wrote an article that covered the most used transformer protection schemes. As was pointed out...
Critical infrastructure security is in the national spotlight. In 2020, the power grid and energy sector was the third most targeted sector for cyber-attacks, up from ninth place in 2019, and the threats are growing more sophisticated. The Biden administration recently issued a national security...
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...
