This paper is devoted to the robust H ∞ and guaranteed cost control problems for continuous-time switched linear systems with polytopic uncertainties, considering an output-dependent switching law and a switched static output feedback controller. The proposed method offers new sufficient conditions based on Linear Matrix Inequalities (LMIs) for designing the switching strategy. In order to provide extra free dimensions in the solution space, some conditions become a special class of Bilinear Matrix Inequalities (BMIs). Therefore, the hybrid algorithm Differential Evolution-Linear Matrix Inequality is proposed for obtaining feasible solutions of this NP-hard problem. Theoretical analyses and numerical examples show that these new procedures reduce the design conservatism of two recent known methods for solving the presented control problems. Besides, a practical application of the method in the design and simulation of a robust switched controller of a switched semi-active suspension is performed.

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Due to the absence of communication needs and great reliability, the droop-control technique is a great choice for controlling of inverters that are subjected to load sharing or to work in an islanded mode. On the other hand, current-controlled inverters are often used in grid-connected systems due to their fast response to power the implementation of maximum power point tracking (MPPT) algorithms to maximize the power extracted from these systems. However, the application of such algorithms in gridconnected droop-controlled systems is hampered by differences in the dynamic responses of the respective techniques. In this context, this study presents the development of a strategy that enables a push-pull converter controlled by MPPT and a low-power plug and play grid-connected inverter governed by droop control to operate stably even under variations in solar radiation. The goal is achieved based on the following two approaches: designing the dclink capacitor properly and using a control loop in order to adapt the droop curves in accordance with the available input power. Theoretical analysis and experimental results have proven the viability of the approach.

This work presents a control methodology in order to enable connecting photovoltaic generators to the grid in such a way that the modules are always going to operate in their maximum power point (MPP). The work uses the droop control technique together with a MPPT method. The integration of these methods presents two crucial points. The first one is how the P-ω curve is modified according to the photovoltaic panel output power and the DC-DC converter output voltage. The second point is the establishment of a DC-link connecting the DC-DC converter to the inverter. Its goal is cancelling the impact caused by the different dynamic response of the methods. This work presents several advantages for environment and reliable and safe power system growing. The experimental results verify great tracking, stability and reliability, even during irradiation transients.