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This note considers stability analysis of a class of pulsewidth modulated (PWM) systems that incorporates several different switched mode de-de converters. The systems of the class typically have periodic solutions. A sampled data model is developed and used to prove stability of these solutions. Conditions for global and local exponential stability are derived using quadratic and piecewise quadratic Lyapunov functions. The state space is partitioned and the stability conditions are verified by checking a set of coupled linear matrix inequalities (LMIs). Index Terms--dc-dc converter, Lyapunov methods, pulsewidth modulated (PWM) systems, sampled data modeling, stability analysis.

High-voltage and high-current SiC bipolar diode modules are fabricated and characterized under static and dynamic conditions. The modules are built using 6 \times 6\ \mm^2 SiC chips that are fabricated on 3-in SiC substrates. Individual chips were also packaged in an ISOPLUS™ package and used to perform switching tests on the diodes. The modules have been fully characterized under static and dynamic conditions. These modules are targeted for high-voltage high-frequency applications as well as antiparallel diodes for 6.5-kV insulated gate bipolar transistors, insulated gate commutated thyristors, and injection enhanced insulated gate bipolar transistors. [ABSTRACT FROM AUTHOR]

Presents information on a study which focused on a parameter estimation method for finite-dimensional multivariate linear stochastic systems. Data models and problem formulation; Parameter estimation of autoregressive moving-average signals; Numerical results; Conclusions.

In this paper a two level hierarchical system is considered. This system consists of two discs that have limited rotational movement. It is assumed that one disc has large inertia and low angular acceleration and the other disc has low inertia and high angular acceleration. The disc with large angular acceleration is mounted on the periphery of the disc with low acceleration. The angular velocity and orientation of both discs is controllable. It is shown how the theory of asymptotic output tracking for linear systems, combined with some easily programmable mathematical optimization problems leads to very good results when designing a controller for asymptotically tracking a moving object, in particular meeting the angular acceleration limits imposed on the two discs. The paradigm for this system is the human eye-head-neck system and the tracking of a moving object at a distance from the eye. [ABSTRACT FROM AUTHOR]