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This study presents a novel topology of a buck-boost converter that features: (i) quadratic voltage gain; (ii) positive output voltage with respect to the input; (iii) continuous input current. Moreover, as the main contribution, (iv) it features a minimum ripple design, for which input current and output voltage ripples are simultaneously cancelled at the desired operating point. It is also shown that even though the duty cycle deviates from a nominal minimum ripple point, the converter exhibits a significantly low switching ripple percentage within a full operation range. The operation mechanism, steady-state equations and overall analysis are presented. Furthermore, simulations and experiments were performed to validate the theory.

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The authors propose a novel step-up converter with stackable switching stages that is suitable for renewable energy applications. On the one hand, the converter gain corresponds to that of the traditional quadratic boost converter, achieving an arbitrary exponential gain in extended configurations. On the other hand, the proposed converter requires a single switch, while the output voltage is partitioned among several capacitors. As argued in this work, the features of the proposed topology represent a significant contribution with respect to standard topologies that exhibit greater voltage stress. The operation principle and the main characteristics of the proposed converter are validated with experimental results.

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Our contribution in this paper is twofold. In the first part, we study Lyapunov functions when a plant is interconnected with a dissipative stabilizing controller. In the second, we present results on data-driven approach to dissipative systems. In particular, we provide conditions under which an observed trajectory can be used to determine whether a system is dissipative with respect to a given supply rate. Our results are based on linear difference systems for which the use of quadratic difference forms play a central role for dissipativity and Lyapunov theory.

We study the stability of switched systems where the dynamic modes are described by systems of higher-order linear differential equations not necessarily sharing the same state space. Concatenability of trajectories at the switching instants is specified by gluing conditions, i.e. algebraic conditions on the trajectories and their derivatives at the switching instant. We provide sufficient conditions for stability based on LMIs for systems with general gluing conditions. We also analyse the role of positive-realness in providing sufficient polynomial-algebraic conditions for stability of two-modes switched systems with special gluing conditions.

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