Reliability is one of the key issues for the application of Silicon carbide (SiC) diode in high power conversion systems. For instance, in high voltage direct current (HVDC) converters, the devices can be submitted to high voltage transients which yield to avalanche. This paper presents the experimental evaluation of SiC diodes submitted to avalanche, and shows that the energy dissipation in th...

This paper describes the modeling and simulation of a wind energy conversion system in Matlab/Simulink environment. The wind energy conversion system consists of a wind turbine, gear box, and induction generator. The dynamic model of a 30 kW induction generator is used for performance testing of the proposed system. Simulink models of the individual components of wind energy conversion are form...

using photovoltaic systems is gradually expanded by increasing energy demand. abundance and availability of this energy, has turned to one of the most important sources of renewable energy. unfortunately, photovoltaic systems have two big problems: first, those have very low energy conversion efficiency (in act between 12 and 42 percent under certain circumstances). second, the power produced b...

A cation-excess (Ni,Mn) ferrite N~o.~zMno.51Fe2.0504.0 with a single phase was synthesized by heating the mixture of corresponding metal salts and oxide in 5% 02175% C02120% N2 gas mixture for 18h at 1100C. It could be thermochemically activated to form a cation-excess ferrite Nio,5z~l+s~Mno.51~l+6~Fe2~05~1+6~0440 in N2 gas at elevated temperature: The ( value was 0.03 1 at 1100C. The activated...

In recent years, there has been a fast growth in wind energy conversion system (WECS). There are two general types of wind turbines in WECS: fixed speed wind turbines and varying speed wind turbines.Permanent magnet synchronous generator (PMSG) is one of the most attractive generators for the varying speed turbine WECS.In this paper, a fuzzy controller is proposed to control the current source ...

It is estimated that the world will need to double its energy supply by 2050. Nanotechnology has opened up new frontiers in materials science and engineering to meet this challenge by creating new materials, particularly carbon nanomaterials, for efficient energy conversion and storage. Comparing to conventional energy materials, carbon nanomaterials possess unique size-/surface-dependent (e.g....