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Multilevel inverters are a new generation of DC–AC converters at medium and high voltage and power levels. In this paper, a new single-phase cascaded multilevel inverter is presented. For this purpose, a new basic cell is presented at first. Then, the new multilevel inverter structure is yielded by series connection of these cells. The proposed new cell is only capable of generating positive voltage levels, and therefore, to produce zero and negative voltage levels, the proposed structure is constructed based on H-bridge module. In order to reduce the maximum blocking voltage especially on H-bridge switches, the cascaded connection of the proposed converter is investigated. A comprehensive comparison is carried out between the proposed multilevel inverter with the classical and recently introduced structures in terms of the number of switching devices, the number of drivers, the total blocking voltage of the switches as well as the loss and efficiency. The accuracy of the proposed inverter's performance is simulated in MATLAB/Simulink in symmetric and asymmetric topologies for a 17-level and 23-level output voltage respectively, and then evaluated by the laboratory prototype. [ABSTRACT FROM AUTHOR]

In this paper, a new approach is recommended for damping out power system oscillations. In this approach, a new fuzzy neural proportional–integral (PI) controller (FNPIC) based static synchronous series compensator (SSSC) and a fuzzy-power system stabilizer (fuzzy-PSS) with a new structure are simultaneously employed. Adaptive learning rates based on the Lyapunov stability theory to enhance the convergence speed of the proposed controller are obtained. In the structure of fuzzy-PSS, a pattern search algorithm is used to adjust four gains. A two-area four-machine power system and a three-area, three-machine power system are employed to investigate the efficiency of the proposed method. Simulations results confirm the capabilities of proposed controller in suppressing the power system oscillations. [ABSTRACT FROM AUTHOR]