The most common cause of power transformer failures is mechanical defect brought about by excessive vibration, which is formed by the combination of multiples of a frequency of 120 Hz. In this paper, the types of mechanical exciting forces applied to the power transformer were classified, and the mechanical damage mechanism of the power transformer was identified using the vibration transfer ro...

The power transformer is one of the most important equipment in a power system. Optimal design of transformer involves determination of design parameters of a power transformer when a chosen objective is optimized, simultaneously satisfying a set of constraints. In this paper Simulated Annealing (SA) is used for optimization of Power Transformer Design (OPTD).The total mass of core and copper i...

In this paper, a new model based on the thevenin equivalent circuit 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 transformer is considered. The ultra-saturation phenomenon causes the mal-operation of the power transformer differential protection. So, the description a...

Power system overvoltages due to switching, lightning and other disturbances are the main problem for designers of the power transformers. Once some frequencies of the incoming surges match with some of the natural frequencies of transformer winding, the resonance phenomenon is expected in transformer winding. The resonant overvoltages may destroy the insulation between turns and cause to insul...

We present an automatic source-level transformer for DSP applications written in MATLAB. Our transformer is based on a novel approach to specify the transformations in an XML-based language resulting in a simple implementation of the transformer as a rewriting engine. In an earlier study we have identified transformations that pay off handsomely for DSP applications. This paper describes the d...

The modeling of power transformer faults and its application to performance evaluation of a commercial digital power transformer relay are the objective of this study. A new method to build an EMTP/ATP power transformer model is proposed in this paper. Detailed modeling of the transformer relay is also discussed. The transient waveforms generated by ATP under different operating conditions are ...

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...

In transformers the main consequence of harmonic currents is an increase in losses, mainly in windings, because of the deformation of the leakage fields. Higher losses means that more heat is generated in the transformer so that the operating temperature increases, leading to deterioration of the insulation and a potential reduction in lifetime. This paper includes the effects of non-sinusoidal...

DC bias current flowing into the neutral point of power transformer will seriously affect the normal operation of AC power system. In this paper, exciting current, harmonic component of the excitation current, magnetic flux density and noise of transformer were analyzed when the transformer is in the no-load operation state based on field-circuit coupled method. Through the calculation and anal...