Frequency Dependent Capacitance and Conductance–Voltage Characteristics of Nitride GaAs Schottky Diode

Semiconductors - A nitride GaAs Schottky diode have been fabricated by nitridation of GaAs substrates with thickness 0.7 nm of GaN layer. The capacitance–voltage C(V) and...     

Numerical Simulation of Differential Systems Displaying Rapidly Oscillating Solutions

The aim of this article is to describe an approximation procedure for stiff differential equations producing highly oscillating solutions. For the sake of simplicity the presentation is restricted to ordinary differential equations. The procedure and the general approximation results are presented. Then the general results are applied to a number of simple explicit systems, for which numerical simulations of the exact and approximate solutions are performed and compared.     

A Study of Adhesive/Material/Surface Interactions for Galvanized Steel Sheet Assemblies

The mechanical strength of bonded joints depends on a large number of factors, among which the adhesive-material-surface combination plays a dominant role. The analysis of the exact roles of these different factors during short destructive tests is delicate due to the complexity of the system. The use of a relatively simple experimental technique, the tensile test, has allowed us to perform a large number of tests and to apply a statistical analysis to the results. For galvanized steel sheets we have thus been able to specify the relative importance of each parameter in the bonding phenomenon and to indicate the interactions between these parameters, particularly for the material and surface condition pair.     

Fixed-switching-frequency DTC control for PM synchronous machine with minimum torque ripples

In this paper, fixed-frequency direct torque control (DTC) of a permanent magnet synchronous motor (PMSM) is presented. In this method, the stator voltage vector is generated according to the increase stator flux components in the stationary frame ( , ). A control algorithm based on predictive control to reduce the effect of the computing time on the stator flux vector position is also presented. The implementation of this method in the case of a PMSM, which is done without hysteresis regulators, is simple and does not require any filter. Simulation and experimental results show that the proposed method reduces the torque ripple while achieving a good dynamic response.