The key gas method identifies the key gas for each type of fault and uses the percent of this gas to diagnose the fault. Focuses on which gas is the largest portion of TDCG (the “key” gas). key gas method was developed mainly from either sealed or gas blanketed transformer. In this method the presence of certain key gases is monitored. Improvement of DGA interpretation using scoring index method Abstract: Dissolved gas analysis (DGA) is the most effective method to detect incipient faults in power transformers. The DGA methods such as Key Gas method, Total Dissolved Combustible Gas (TDCG), Dörnenburg Ratio method, Rogers Ratio method and Duval Triangle method are applied to assess actual condition of distribution transformer. Dissolved gas analysis (DGA) is a reliable technique for detecting the presence of incipient fault conditions in oil immersed transformers.
Key gases formed by degradation of oil and paper insulation are hydrogen (H 2), methane (CH 4), ethane (C 2 H 6), ethylene (C 2 H 4), acetylene (C 2 H 2), Carbon monoxide (CO) and oxygen (O 2). China warns against US sending missiles to Japan; China's massive flooding to get worse - Duration: 15:55. A total of 50 distribution transformers in Thailand are analyzed and compared … Useful for benchmarking in the normal range, and to confirm diagnoses in the warning range. Dissolved Gas Analysis monitoring is a major component of a comprehensive transformer monitoring system. 20 Key Gas Method Key Gas Method Considered as a modification of the TDCG procedure. Ratio methods and Total Dissolved Combustible Gas (TDCG) method are applied for supporting operational decisions. DGA Monitor Comparison Chart.
Dissolved gases analysis (DGA) is one of the most effective methods in the diagnosis of electrical equipment such as transformers. Each type of DGA method may evaluate different types of gas for analysis. All five methods are developed by excel program for simple usage with minimum cost of utility. The various analysis methods are : Rogers ratio, IEC ratio, Doernenburg, Duval triangle, key gas, artificial neural network (ANN) method.
In Dominion Energy online DGA monitoring system, the Key Gas method is employed as the primary analysis method for event thresholds. Permits a tentative determination of possible fault types empirically determined from a transformer’s unique gas profile. The key gas method identities the key gas for each type of faults and uses the percent of this gas to diagnose the fault [9]. Griffin gave an extensive review on the key gas method, the ratio methods, and related application issues [Griffin88]. Dynamic Ratings supports communication to all major DGA monitors. China in Focus - NTD Recommended for you.
New We recognize that DGA monitors have different advantages and no one product would be optimal for all customers. It uses the concentrations of various gases dissolved in the transformer oil due to decomposition of the oil and paper insulation.