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A consistent framework for robust linear quadratic regulators (LQRs) control of power converters is presented. Systems with conventional LQR controllers present good stability properties and are optimal with respect to a certain performance index. However, LQR control does not assure robust stability when the system is highly uncertain. In this paper, a convex model of converter dynamics is obtained taking into account uncertainty of parameters. In addition, the LQR control for switching converters is reviewed. In order to apply the LQR control in the uncertain converter case, we propose to optimize the performance index by using linear matrix inequalities (LMIs). As a consequence, a new robust control method for dc-dc converters is derived. This LMI-LQR control is compared with classical LQR control when designing a boost regulator. Performance of both cases is discussed for load and line perturbations, working at nominal and nonnominal conditions. Finally, the correctness of the proposed approach is verified with experimental prototypes. [ABSTRACT FROM AUTHOR]

In this paper, the problem of paralleling dc-dc switching converters is solved by means of power gyrators. The key element of the parallel connection is a buck converter with input filter acting as a power gyrator of type G with controlled output current, i.e., with its dc output current being proportional to its dc input voltage, electromagnetic interference minimization, current distribution among converters, stability, and voltage regulation are ensured by this approach. It is shown that a voltage regulator based on the parallel operation of power gyrators with democratic current sharing is always stable regardless of the number of connected modules. Experimental results of a dc-dc voltage regulator based on the parallel connection of three power gyrators with democratic current sharing are in perfect agreement with the theoretical predictions. [ABSTRACT FROM AUTHOR]

Investigates the use of neural networks (NN's) for identification and control of power converters. Analysis of approximation by means of NN's of nonlinear control techniques suitable for large-signal operation; What simulation results in a pulsewidth-modulated (PWM) boost converter under large-signal operation illustrates; Directions for future work.