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Condition Monitoring of Transformers is the process of acquisition and processing of data related to various parameters of transformers so as to predict and prevent the failure of a transformer. This is done by observing the deviation of the transformer parameters from their expected values. Transformers are the most critical assets of electrical transmission and distribution system. Transformer failures could cause power outages, personal and environmental hazards and expensive rerouting or purchase of power from other suppliers. Transformer failures can occur due to various causes. Transformer in-service interruptions and failures usually result from dielectric breakdown, winding distortion caused by short-circuit withstand, winding and magnetic circuit hot spot, electrical disturbances, deterioration of insulation, lightning, inadequate maintenance, loose connections, overloading, failure of accessories such as OLTCs, bushings, etc.() Integrating the ‘individual cause’ monitoring allows for monitoring the overall condition of transformer. The important aspects of condition monitoring of transformers are () # Thermal Modelling # Dissolved Gas Analysis # Frequency Response Analysis # Partial Discharge Analysis ==Thermal Modelling== The useful life of a transformer is determined partially by the ability of transformer to dissipate the internally generated heat to its surroundings (). The comparison of actual and predicted operating temperatures can provide a sensitive diagnosis of the transformer condition and might indicate abnormal operation. The consequences of temperature rise may not be sudden, but gradual as long as it is within break down limit. Among these consequences, insulation deterioration is economically important. Insulation being very costly, its deterioration is undesirable. Thermal modeling is the development of a mathematical model that predicts the temperature profile of the power transformer using the principle of thermal analysis. The thermal model is used to determine the top oil temperature and hot spot temperature(maximum temperature occurring in the winding insulation system) 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Condition monitoring of transformers」の詳細全文を読む スポンサード リンク
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