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ABSTRACTThis article proposes an enhanced non-isolated high-gain DC-DC converter for interfacing renewable energy sources (RESs). This converter utilizes active switched-inductor (ASL) and switched-capacitor (SC) networks in which the ASL network increases the voltage gain. Furthermore, using the SC network as a multiplier cell helps to reach a high voltage conversion ratio with a proper duty cycle. The main advantages of the proposed converter are the high voltage gain, continuous input current, and low voltage stress on the semiconductor switch and the passive component. Since the voltage stress of the semiconductor element is low, a low ON-state resistance switch is used, which leads to reduced conduction losses. Comprehensive analysis of the steady-state operation in continuous conduction mode (CCM), inductor and capacitor design, and a comparison considering other similar topologies are presented in this article. Also, the parasitic elements are assumed to calculate the DC-Voltage gain and the efficiency of the converter. Finally, simulation results are presented in the PSIM environment to validate the feasibility of the proposed converter.

ABSTRACTThe 2/3-level hybrid inverters are a combination of three-level Neutral Point Clamped (NPC) inverter and conventional two-level inverter, which has the advantage of both two-level and three-level structures with fewer switches than the NPC inverter. In this paper, a new structure of 2/3 hybrid inverter based on dual-Z-‏source network is proposed. The proposed structure improves the performance of the 2/3-level inverter and increases its independent DC input voltages. The output voltage gain can be obtained by selecting the shoot-through interval appropriately in dual Z-source networks. In addition, shoot-through intervals in Z-source networks allow the inverter to run without dead time, thus increasing the output voltage quality. A modified switching method is presented for the proposed inverter, and the necessary calculations are performed. The proposed structure can be used to connect different distributed generation sources to the load separately from the grid or to the low-pressure network. The performed simulations show the accuracy of the proposed structure.