In this paper a new topology for Dynamic Voltage Restorer (DVR) with high frequency link is proposed. This topology is able to compensate different types of voltage disturbances such as voltage sag, voltage swell and voltage harmonics. According to the obtained equations, this topology operates as a controllable current source to charge the series capacitor. Due to using High Frequency Transfor...

This work presents a micromachined RF-CMOS transformer fabricated in a commercially available 0.18μm CMOS process. Maskless micromachining post-processing is used to remove oxide and substrate material from around the transformer, reducing parasitic effects and improving the performance of the transformer. Index Terms — baluns, CMOS integrated circuits; MEMS, maskless micromachining, Q enhancem...

The experimental and theoretical results of a ZVS (Zero Voltage Switching) isolated flyback DC-DC converter using multilayered coreless PCB step down 2:1 transformer are presented. The performance characteristics of the transformer are shown which are useful for the parameters extraction. The measured energy efficiency of the transformer is found to be more than 94% with the sinusoidal input vo...

This paper presents a new step-up DC/DC converter topology to be used for distributed energy systems. The topology contains a voltage-fed quasiZ-source inverter with continuous input current, a high-frequency step-up isolation transformer and a voltage doubler rectifier. Main operating modes of the converter are explained and steady state analysis of the voltage-fed quasi-Z-source inverter is p...

Possibilities for increased mine detection and classification techniques have established a need for broadband, underwater acoustic projectors. An advanced version of a low frequency synthetic aperture sonar (SAS) for the mine reconnaissance hunter program has recently been developed. The transducer is resonant at 100 kHz but has been designed to deliver constant high sound pressure levels over...

Based on natural ventilation design scheme for main transformer room of an indoor substation, different air distribution schemes were obtained by changing height and size of air inlets and outlets. Three-dimensional simulation of air distribution was conducted for the transformer room by using Computational Fluid Dynamics (CFD) method. Ventilation & cooling effect of different indoor ventilatio...

By the analysis of transfer function mechanical deformations or displacements of transformer windings can be detected. For on site measurements on large power transformers essential attention has to be put on accurate cabling and handling of grounding conductors. Of further concern is the selection of a meaningful upper frequency limit, from where beyond measurements of frequency responses are ...

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...