This paper introduces a high precise direct current (DC) negative high voltage power supply. The supply’s output voltage is 25kV and its maximal output current is 100mA. The power supply uses BOOST converter for power factor correction and voltage regulation. It converts DC to high frequency (HF) alternating current (AC) square wave with phase-shifted full bridge. The voltage of the AC square w...

A PV pumping system using induction machine is thoroughly investigated in this work. The power structure is constituted of multiple parallel DC/DC step-up converters directly connected to the inverter. Each DC/DC converter is used as a DC current transformer. The input characteristic of the inverter is enforced by means of an appropriate regulation, in order to avoid problematic dynamic resista...

Soft-switching DC-DC converter using Phase-Shifted Pulse Width Modulation (PS-PWM) on secondary side of highfrequency transformer is described in the paper. The converter consists of a full-bridge inverter fitted with fast IGBT transistors. The output power of the converter is controlled by rectifier made up of two snap-off diodes in series with MOSFET transistors which is connected on secondar...

Renewable energy sources like solar and fuel cells are emerging as a promising supplementary power sources due to their merits of cleanness, high efficiency, and high reliability. But the output levels of these are low. An isolated bidirectional full-bridge dc–dc converter can be used for interfacing battery to the system. Because of the presence of leakage inductance of the isolation transform...

The recent development of high power DC/DC converters (more commonly know as Chopper Rectifiers) allows customers the option to keep older rectifier transformers and refurbished systems if reconfiguring or installing new cell line loads. Normally, new cell line impedances would require the replacement of transformer/rectifier equipment. This paper is intended to describe how one can change the ...

DC bias will cause abnormal vibration of transformers. Aiming at such a problem, transformer vibration affected by DC bias has been studied combined with transformer core and winding vibration mechanism use multi-physical field simulation software COMSOL in this paper. Furthermore the coupling model of electromagnetic-structural force field has been established, and the variation pattern of inn...

Abstract Piezoelectric transformers are mainly commercialized for a LCD back light inverter module. With regard to laptop computers, the required output power for a piezoelectric transformer is around 5 W at present, and higher power will be needed for wider displays in the near future. In addition, modules such as AC-DC adaptors or fluorescent lamps may require a higher output power of more th...

This paper describes vibration diagnosis based on electric faults. These faults could appear in electrical equipment in general, but this paper focuses on the case of transformer, induction and dc motor. In order to do the diagnosis there are analysed vibration signals from the piezoelectric accelerometer. This accelerometer is installed on the frame of the equipment. The signals acquired are a...

A real time on-line transformer vibration monitoring system based on the Labview is proposed and applied in the monitoring of abnormal vibration of transformer caused by DC bias in this paper. The monitoring of the transformer body vibration and the signal online analysis can be well performed by this system. The vibration signals of the transformer body are detected by three acceleration senso...

A high step-up DC-to-DC converter that integrates an isolated transformer and a switched-clamp capacitor is presented in this study. The voltage stress of the main power switch should be clamped to 1/4 V by using the turn ratio and switched-clamp capacitor of an isolated transformer to achieve a high voltage gain. In addition, a passive clamp circuit is employed reduce voltage stress on the mai...