The aim of this paper is to extend a hybrid protection plan for Power Transformer (PT) based on MRA-KSIR-SSVM. This paper offers a new scheme for protection of power transformers to distinguish internal faults from inrush currents. Some significant characteristics of differential currents in the real PT operating circumstances are extracted. In this paper, Multi Resolution Analysis (MRA) is use...

Generation, transmission and distribution of electric energy are to be characterized by a very high degree of reliability. Reliability level is directly related to the quality of the equipment used and the periodic maintenance carried out on the system. In our country, the distribution system is the most neglected part, which is being given some importance only in the recent years. Distribution...

To My lovely wife, Tong Wang And my to-be-born baby girl, Lucia Wang i ABSTRACT This dissertation is a systematic study of artificial intelligence (AI) applications for the diagnosis of power transformer incipient fault. The AI techniques include artificial neural networks (ANN, or briefly neural networks-NN), expert systems, fuzzy systems and multivariate regression. The fault diagnosis is bas...

This paper presents a new approach for classifying transient phenomena in power transformers, which may be implemented in digital relaying for transformer differential protection. Discrimination of various operating conditions of the power transformer is achieved by combining wavelet transform with Adaptive Neuro Fuzzy Inference system (ANFIS). The wavelet transform is applied for the analysis ...

This paper emphasizes on the use of fuzzy approach in dealing with the incipient fault conditions of power transformer. DGA (Dissolved Gas in Oil Analysis) cannot provide better fault diagnosis results when multiple faults are involved. The boundary values specified by the ratio methods are of limited concern .Considering the limitations of convergence of the conventional neural networks in the...

Certain level of mechanical deformations in winding does not hamper the normal performance of power transformer. However, such incipient deformations if unattended could result in permanent failure of transformer. To this end, an approach is proposed to assess the severity of mechanical deformations in transformer winding. These deformations get reflected as changes in its high frequency behavi...

Internal Turn-Turn faults (TTF) are the most common failures in power transformers, which could seriously reduce their life expectancy. Although common protection schemes such as current-baseddifferential protection are able to detect some of the internal faults, some other minor ones (such as TTFs andshort circuit near the neutral point) cannot be detected by such schemes. Likewise, these rela...

one of the major problems that may occur in the differential protection systems of power transformers is mal-operation of the protection relays in sake of internal fault detection, because of similarity between this current and inrush current. this paper presents a novel approach for discriminating inrush current from internal fault in power transformers based on improved gravitational search a...

protection systems have vital role in network reliability in short circuit mode and proper operating for relays. current transformer often in transient and saturation under short circuit mode causes mal-operation of relays which will have undesirable effects. therefore, proper and quick identification of current transformer saturation is so important. in this paper, an artificial neural network...

Energization of a transformer results in sudden flow of current which is an effect of core magnetization. This current will be dominated by the presence of second harmonic, which in turn is used to segregate fault and inrush current, thus guaranteeing proper operation of the relay. This additional security in the relay sometimes obstructs or delays differential protection in a specific scenario...