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Abstract: Real-time simulation and rapid prototyping of power electronics, critical loads, and control systems have prompted recent interest in accurate electrical terminal models of photovoltaic (PV) panels and array systems. Advancement in computing technologies, such as parallel computing and digital signal processing techniques for real-time simulations have allowed the prototyping of novel apparatus to be investigated in a virtual system under a wide range of realistic conditions repeatedly, safely, and economically. This paper accesses numerical iteration methods, selects appropriate techniques, and combines them with model construction methods well suited for boosting the computational speed of an electro-thermal dynamic model of a PV panel. The target computational engine is a parallel processor based real-time simulator to be used in a power hardware-in-the-loop (PHIL) application. Significant improvements resulting from the proposed modeling approach in computation time and numerical convergence speed are verified using experimental results for the target PV panel using Opal-RT’s RT-Lab Matlab/Simulink based real-time engineering simulator. [Copyright &y& Elsevier]

The performance of a vibration enhanced reverse osmosis membrane module for desalination of artificial seawater was investigated with computational fluid dynamics (CFD) simulations and experiments. The computational model couples fluid dynamics with solutes transport inside the full length domain containing ‘zigzag’ spacers using a two dimensional, transient Large Eddy Simulation turbulence model. Both the local concentration dependent solute properties and variation of permeate flux over the membrane surface were predicted with the model. Membrane local permeate flux, concentration polarization, shear rate, and mass transfer were also calculated. The results suggest concentration polarization in the seawater desalination process could be reduced by imposing vibration on the reverse osmosis membrane. It was determined that the higher the vibration frequency the higher the membrane permeate flux while keeping the vibration amplitude constant. The CFD simulation predictions are validated against experimental data of permeate fluxes with good agreement. [ABSTRACT FROM AUTHOR]

All available Pulse Width Modulation (PWM) techniques employed to different Matrix Converter (MC) topologies generally generate switching Common-Mode Voltage (CMV), which introduces numerous operational concerns in electric drives. Although a body of research for the three-phase case has been undertaken to either reduce or eliminate CMV, corresponding discussions for multiphase MC remain scarce. Interestingly enough, the three- to five-phase (3 × 5) Indirect MC (IMC) is a potential converter topology for five-phase based high power motor drives. In this paper, the different available switching states of a 3 × 5 IMC are classified based on their corresponding CMV levels. Accordingly, two different Space Vector Modulation (SVM) techniques are proposed, which can successfully reduce the peak CMV by 28% and 48%, respectively, when compared with the conventional modulation strategy, while the same maximum Voltage Transfer Ratio (VTR) is preserved. Although the 28% reduction has been alternatively achieved in literature based on carrier-based PWM, the 48% reduction attained in this study represents the maximum achievable reduction for this MC topology. The main concept is firstly introduced; then, both simulations and experiments are used to validate the proposed schemes. [ABSTRACT FROM AUTHOR]