Transformer insulating oil nanofluid is made to improve dielectric and thermal properties of the oil by employing nanoparticles with proper properties. In the current work, nanofluids based on transformer mineral oil were prepared by three procedures using diamond nanoparticles with high thermal conductivity, as well as high dielectric properties. It was tried to consider the impacts of surfact...

Abs t rac t -The phys ica l s ize of inductors in resonant converters was examined i n terms o f inductor t o transformer s i z e rat io . F o l l o w i n g the general d i scuss ion o f the i s s u e , the inductor s i z e i n ser i e s resonant DC-DC converter i s examined i n deta i l . It i s shown that the inductor t o transformer s i z e rat io i s a funct ion of the peak v o l t a g e o ...

Corrosive Sulfur in transformer oil has been the cause of high profile transformer failures in recent years. Oil treatments consisting of copper passivators have been only partially effective. DSI has discovered a multi-step method that has been proven to change oils with corrosive sulfur into non-corrosive status, as well as significantly slowing oxidation and ageing of insulating oil and pape...

Ferroresonance is a non-linear phenomenon and very dynamic in the power quality problems. This phenomenon should be carefully analyzed so that preventive measures could be taken before its appearance and prevent injury and damage to electrical power appliances. Ferroresonance is seen more in the middle-voltage networks with supplying unloaded or slightly loaded transformers by cables. The mater...

In this paper, a combined neural network and an evolutionary programming scheme is proposed to improve the quality of wound core distribution transformers in an industrial environment by exploiting information derived from both the construction and transformer design phase. In particular, the neural network architecture is responsible for predicting transformer iron losses prior to their assemb...

The stress response in Drosophila melanogaster reveals sex differences in behavior, similar to what has been observed in mammals. However, unlike mammals, the sex determination pathway in Drosophila is well established, making this an ideal system to identify factors involved in the modulation of sex-specific responses to stress. In this study, we show that the Drosophila fat body, which has be...

In this study, a disk-shaped piezoelectric transformer was fabricated using lead-free (K,Na)NbO(3)-based ceramics with high mechanical quality factor. The transformer can operate in the fundamental or the third radial vibration mode. The transformer is poled along the thickness direction. The top surface is covered by ring/dot silver electrodes separated by an annular gap which serve as the inp...

Geomagnetically Induced Currents (GIC) are supposed to be a threat to power transformers worldwide. Recent surveys show correlation between solar storm activities, the cause of GIC, and transformers failing within a relatively short time period. The scope of this contribution is to create and investigate a laboratory setup emulating GIC effects by injecting DC currents into a three phase power ...