The internal faults of transformer can be identified by various techniques. The proposed technique is by the analysis of no-load current and harmonic contents present in it. The no-load current of transformer is non-sinusoidal for sinusoidal input voltage. And hence it contains harmonics in healthy condition of transformer. But if transformer has any internal fault then the no-load current magn...

The paper investigates the behavior of four transformer models in electromagnetic transients programs (EMTP) when calculating inrush currents due to shell-type transformers energization. These models are single-phase Saturable Transformer (STC), BCTRAN, Hybrid Transformer (XFMR) and UMEC. The measurements of a real transformer energization performed by EDF in France are used to evaluate the acc...

This paper presents a current transformer model that is useful on low frequency applications. To describe the iron core magnetic behaviour of the iron core, a hysteresis model is proposed, which is able to generate minor asymmetric loops and remanent flux. The effects of classic eddy current losses and anomalous losses are represented by linear and nonlinear resistors, respectively. The obtaine...

Airport ground lighting (AGL) systems provide visual reference to aircrafts during airport operations. In AGL systems, constant current regulators feed a beacon circuit supplied through isolation transformers. Component modeling is necessary to simulate AGL systems, and thus characterize and predict their behavior. This paper presents an isolation transformer model including transformer core sa...

One of transient phenomenon that causes the mal-operation of the power transformer differential protection during the energization of a loaded power transformer is the ultra-saturation phenomenon. In this paper, a new model for investigating the ultra-saturation phenomenon during the energization of a loaded power transformer is presented and its effect on the differential protection of the pow...

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...