Remaining Life of the oil-immersed transformer is decided due to deterioration of the winding ins... more Remaining Life of the oil-immersed transformer is decided due to deterioration of the winding insulation paper (WIP). The DGA method is conventionally used to estimate the WIP deterioration status condition. This paper presented the four status conditions assessment ...
The gases generated in oil filled transformer can be used for determination of incipient faults. ... more The gases generated in oil filled transformer can be used for determination of incipient faults. Dissolved gas analysis (DGA) of transformer oil has been one of the most power full methods to detect the faults. The various methods such as liquid chromatography, acoustic analysis, and transformer function techniques are require some experience to interpret observations. The researchers have used artificial intelligence (AI) approach to encode these diagnostic techniques. This paper presents fuzzy-logic application and an overview of ANN techniques which can diagnose multiple faults in a transformer. Theoretical and practical fuzzy-logic (FL) information model and various researchers' ANN based experimental conclusion have been presented. This paper includes a demonstration of the application of the FL technique for transformer incipient fault diagnosis.
This paper present the transformer design optimization problem. The objective of transformer desi... more This paper present the transformer design optimization problem. The objective of transformer design optimization problem requires to minimizing the total mass (or cost) of the core and wire material by satisfying constraints imposed by international standards and transformer user specification. The constraints include appropriate limits on efficiency, voltage regulation, temperature rise, no-load current and winding fill factor. The design optimizations seek a constrained minimum mass (or cost) solution by optimally setting the transformer geometry parameters and require magnetic properties. This paper shows the above design problems can be formulated in fuzzy logic (FL). The importance of the FL format stems for two main features. First it provides efficient and reliable solution for the design optimization problem with several variables. Second, it guaranteed that the obtained solution is global optimum. This paper includes a demonstration of the application of the FL technique for transformer design.
Diagnosis of power transformers becomes important due to the age of the transformer in service. D... more Diagnosis of power transformers becomes important due to the age of the transformer in service. Diagnosis methods can be separated in integral or differential methods. This paper describes a realistic Health Index formulation method for power transformers using readily available data. The method considers practical limitations on obtaining data, and the possible constraints on the parameters. This Health Index estimation considers not only typical test results such as dissolved gas analysis (DGA), oil quality, furan, and power factor, but also other parameters such as frequency response analysis (FRA), turn ratio, tap changer and bushing condition, physical observations, load history, maintenance work orders, and In-Service age of transformer. The calculation includes condition ratings, weighting factors, and assigned scores for specific condition parameters. By using a multi-criteria analysis approach, the method combines the various factors into a condition-based Health Index.
Abstract The paper presents power transformer design, using genetic algorithm (GA) and simulated ... more Abstract The paper presents power transformer design, using genetic algorithm (GA) and simulated annealing (SA) by minimizing total active cost, keeping in view the constraints imposed by international standards and power transformer specifications. The design ...
Transformer is one of the costliest apparatus in an electrical power supply network which play vi... more Transformer is one of the costliest apparatus in an electrical power supply network which play vital role in an electrical power system. It is expected that all transformers installed in a substation must function optimally under normal as well transient conditions. Their satisfactory performance of transformers can be ensured by making use of latest trends in condition based monitoring. This helps not only in providing interruption free electricity supply but also help in enhancing attain prolonged residual life and hence capital management of the utilities. Forecasting transformer costs by its manufacturer and industrial companies has always been an area of interest especially in modern era of technology advancements when newer and newer material are pouring into market for the use by manufacturers. The major amount of transformer costs are related to its raw materials, So, the cost estimation process of transformers are based on amount of used raw material. This paper presents a new method to estimate the weight of main materials for transformers by use of fuzzy logic technique. The required estimating data have been obtained from Transformer Company.
Transformer is one of the vital components in electrical network which play important role in the... more Transformer is one of the vital components in electrical network which play important role in the power system. The continuous performance of transformers is necessary for retaining the network reliability, forecasting its costs for manufacturer and industrial companies. The major amounts of transformer costs are related to its no-load loss, so the cost estimation processes of transformers are based on reduction of no-load loss. This paper presents a new method for classification of transformer no-load losses. It is shown that ANNs are very suitable for this application since they present classification success rates between 78% and 96% for all the situations examined. The method is based on Multilayer Perceptron Neural Network (MPNN) with sigmoid transfer function. The Levenberg-Marquard (LM) algorithm is used to adjust the parameters of MPNN. The required training data are obtained from transformer company.
Remaining Life of the oil-immersed transformer is decided due to deterioration of the winding ins... more Remaining Life of the oil-immersed transformer is decided due to deterioration of the winding insulation paper (WIP). The DGA method is conventionally used to estimate the WIP deterioration status condition. This paper presented the four status conditions assessment of paper deterioration for oil-immersed transformer using fuzzy-logic (FL). In this paper the correlation between accumulated values of carbon dioxide (CO2) and
Abstract UV-Spectrophotometer response is a nonintrusive test used to determine the transformer i... more Abstract UV-Spectrophotometer response is a nonintrusive test used to determine the transformer integrity. Information about the health of the power transformer that can be use to plan cost, maintenance, relocation and operational criteria can be accurately interpreted ...
In electrical system, power transformers are as interface between different voltage levels of ess... more In electrical system, power transformers are as interface between different voltage levels of essential importance. Because of the long manufacture process transformers are one of the most critical and expensive equipment and so this is one of the reasons why condition monitoring becomes more popular. Monitoring systems as basis for diagnostics open the possibility for expanding the operating time, reducing the risk of expensive failures and allows several maintenance strategies. With different monitoring techniques detailed information about the transformer condition can be received and helps to minimize the probability of an unexpected outage. In this paper a methodology has been developed to use information derived from condition monitoring and diagnostics for rehabilitation purposes of transformers. The interpretation and understanding of the test data are obtained from the International Standards.
ABSTRACT This communication presents a study showing that mobile phone usage duration have got a ... more ABSTRACT This communication presents a study showing that mobile phone usage duration have got a significant effect on the EMI characteristics. This is because the long-time operation (transmitting and receiving) of the mobile phone cause their hardware to worn-out over a period of time to significant extent. Hence, the operation of worn-out elements introduces errors that degrade the performance of the power flow control algorithms along with the hardware, which in turn result in poor power flow control in different hardware of mobile phone. This leads to the generation of interference and compels a handset to violate the EMC regulations. This degrades the quality of the mobile phone services and leads to malfunctioning of electric/electronic devices in its vicinity and also to the systems connected to the same grid.
Remaining Life of the oil-immersed transformer is decided due to deterioration of the winding ins... more Remaining Life of the oil-immersed transformer is decided due to deterioration of the winding insulation paper (WIP). The DGA method is conventionally used to estimate the WIP deterioration status condition. This paper presented the four status conditions assessment ...
The gases generated in oil filled transformer can be used for determination of incipient faults. ... more The gases generated in oil filled transformer can be used for determination of incipient faults. Dissolved gas analysis (DGA) of transformer oil has been one of the most power full methods to detect the faults. The various methods such as liquid chromatography, acoustic analysis, and transformer function techniques are require some experience to interpret observations. The researchers have used artificial intelligence (AI) approach to encode these diagnostic techniques. This paper presents fuzzy-logic application and an overview of ANN techniques which can diagnose multiple faults in a transformer. Theoretical and practical fuzzy-logic (FL) information model and various researchers' ANN based experimental conclusion have been presented. This paper includes a demonstration of the application of the FL technique for transformer incipient fault diagnosis.
This paper present the transformer design optimization problem. The objective of transformer desi... more This paper present the transformer design optimization problem. The objective of transformer design optimization problem requires to minimizing the total mass (or cost) of the core and wire material by satisfying constraints imposed by international standards and transformer user specification. The constraints include appropriate limits on efficiency, voltage regulation, temperature rise, no-load current and winding fill factor. The design optimizations seek a constrained minimum mass (or cost) solution by optimally setting the transformer geometry parameters and require magnetic properties. This paper shows the above design problems can be formulated in fuzzy logic (FL). The importance of the FL format stems for two main features. First it provides efficient and reliable solution for the design optimization problem with several variables. Second, it guaranteed that the obtained solution is global optimum. This paper includes a demonstration of the application of the FL technique for transformer design.
Diagnosis of power transformers becomes important due to the age of the transformer in service. D... more Diagnosis of power transformers becomes important due to the age of the transformer in service. Diagnosis methods can be separated in integral or differential methods. This paper describes a realistic Health Index formulation method for power transformers using readily available data. The method considers practical limitations on obtaining data, and the possible constraints on the parameters. This Health Index estimation considers not only typical test results such as dissolved gas analysis (DGA), oil quality, furan, and power factor, but also other parameters such as frequency response analysis (FRA), turn ratio, tap changer and bushing condition, physical observations, load history, maintenance work orders, and In-Service age of transformer. The calculation includes condition ratings, weighting factors, and assigned scores for specific condition parameters. By using a multi-criteria analysis approach, the method combines the various factors into a condition-based Health Index.
Abstract The paper presents power transformer design, using genetic algorithm (GA) and simulated ... more Abstract The paper presents power transformer design, using genetic algorithm (GA) and simulated annealing (SA) by minimizing total active cost, keeping in view the constraints imposed by international standards and power transformer specifications. The design ...
Transformer is one of the costliest apparatus in an electrical power supply network which play vi... more Transformer is one of the costliest apparatus in an electrical power supply network which play vital role in an electrical power system. It is expected that all transformers installed in a substation must function optimally under normal as well transient conditions. Their satisfactory performance of transformers can be ensured by making use of latest trends in condition based monitoring. This helps not only in providing interruption free electricity supply but also help in enhancing attain prolonged residual life and hence capital management of the utilities. Forecasting transformer costs by its manufacturer and industrial companies has always been an area of interest especially in modern era of technology advancements when newer and newer material are pouring into market for the use by manufacturers. The major amount of transformer costs are related to its raw materials, So, the cost estimation process of transformers are based on amount of used raw material. This paper presents a new method to estimate the weight of main materials for transformers by use of fuzzy logic technique. The required estimating data have been obtained from Transformer Company.
Transformer is one of the vital components in electrical network which play important role in the... more Transformer is one of the vital components in electrical network which play important role in the power system. The continuous performance of transformers is necessary for retaining the network reliability, forecasting its costs for manufacturer and industrial companies. The major amounts of transformer costs are related to its no-load loss, so the cost estimation processes of transformers are based on reduction of no-load loss. This paper presents a new method for classification of transformer no-load losses. It is shown that ANNs are very suitable for this application since they present classification success rates between 78% and 96% for all the situations examined. The method is based on Multilayer Perceptron Neural Network (MPNN) with sigmoid transfer function. The Levenberg-Marquard (LM) algorithm is used to adjust the parameters of MPNN. The required training data are obtained from transformer company.
Remaining Life of the oil-immersed transformer is decided due to deterioration of the winding ins... more Remaining Life of the oil-immersed transformer is decided due to deterioration of the winding insulation paper (WIP). The DGA method is conventionally used to estimate the WIP deterioration status condition. This paper presented the four status conditions assessment of paper deterioration for oil-immersed transformer using fuzzy-logic (FL). In this paper the correlation between accumulated values of carbon dioxide (CO2) and
Abstract UV-Spectrophotometer response is a nonintrusive test used to determine the transformer i... more Abstract UV-Spectrophotometer response is a nonintrusive test used to determine the transformer integrity. Information about the health of the power transformer that can be use to plan cost, maintenance, relocation and operational criteria can be accurately interpreted ...
In electrical system, power transformers are as interface between different voltage levels of ess... more In electrical system, power transformers are as interface between different voltage levels of essential importance. Because of the long manufacture process transformers are one of the most critical and expensive equipment and so this is one of the reasons why condition monitoring becomes more popular. Monitoring systems as basis for diagnostics open the possibility for expanding the operating time, reducing the risk of expensive failures and allows several maintenance strategies. With different monitoring techniques detailed information about the transformer condition can be received and helps to minimize the probability of an unexpected outage. In this paper a methodology has been developed to use information derived from condition monitoring and diagnostics for rehabilitation purposes of transformers. The interpretation and understanding of the test data are obtained from the International Standards.
ABSTRACT This communication presents a study showing that mobile phone usage duration have got a ... more ABSTRACT This communication presents a study showing that mobile phone usage duration have got a significant effect on the EMI characteristics. This is because the long-time operation (transmitting and receiving) of the mobile phone cause their hardware to worn-out over a period of time to significant extent. Hence, the operation of worn-out elements introduces errors that degrade the performance of the power flow control algorithms along with the hardware, which in turn result in poor power flow control in different hardware of mobile phone. This leads to the generation of interference and compels a handset to violate the EMC regulations. This degrades the quality of the mobile phone services and leads to malfunctioning of electric/electronic devices in its vicinity and also to the systems connected to the same grid.
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