Series connection of semiconductor submodules (SM) in a modular multilevel converter (MMC) makes the MMC prone to open-circuit (OC) IGBT failures inside SMs. If left undetected, these faults degrade operation and lead its instability. This article proposes method detect, localise, classify single OC SM an using support vector machines (SVM) trained with data obtained from capacitor voltage bala...

Due to their lightweight, new classes of materials including aluminium-based Metal Matrix Composites (MMCs) have been popular in recent years various industries aircraft and automobiles. Because its low cost ease availability, aluminium alloy (LM13) MMCs were developed using Rice husk ash (RHA) as reinforcement this study rather than traditional composites prepared the stir casting technique. L...

This article develops a small-signal impedance model of modular multilevel converters (MMCs) using the harmonic state-space (HSS) method and studies stability in multiple converter scenario. In order to simplify analysis coupling characteristics between different frequencies MMCs, proposed is developed positive–negative–zero (PN0) sequence frame, where zero-sequence current three-phase three-wi...

Conference control has been studied for years but most researches focus on homogenous A/V collaboration. There is no conference control framework for integration of multiple videoconferencing systems such as H.323, SIP and AccessGrid. In this paper, we propose a webserviced based scalable conference control framework for such heterogeneous collaboration system. Based on XGSP A/V Web-Services fr...

In this present study, A356.2 Al/Rice hush ash (RHA) metal matrix composites (MMCs) were fabricated by vortex method. Different weight fractions of reinforcement were used to fabricate the composites. Scanning electron microscope equipped with energy dispersive Xray analyzer is used for micro structural characterization. The properties like density, hardness, and ultimate tensile strength were ...

Modular multilevel converters (MMCs) will be widely applied in onboard integrated power systems due to their high levels of electric output and good-quality sine waveform outputs. However, the capacitor voltage MMCs fluctuates greatly because charge–discharge process is continuous when system working. In order reduce ripples efficiently, a ripple-suppression strategy employing reversed PWM swit...

in this study, al/al2o3 composites with two different particle sizes of 1 µm and 0.3 µm were produced via accumulative roll bonding (arb). the microstructure evolution, mechanical properties and fracture behavior of the composites were investigated. results show that higher arb cycles are required to achieve a uniform distribution of particles in the composite with 0.3 µm particle size. during ...

Metal matrix composites (MMCs) belong to a group of modern materials owing their excellent technological, mechanical, and physical properties such as wear corrosion resistance, high electrical thermal conductivity, improved strength hardness. Final MMCs are affected equally by all steps its manufacturing process. It is shown that using adequate process parameters obtain starting (reaching the s...