No abstract

Summary The Z‐source network idea has opened up a new research area in the power electronics field. In this paper, a new switched‐inductor network, called extended switched‐inductor quasi‐Z‐source inverter (ESL‐qZSI), is proposed. From a topological point of view, the new inverter has an additional inductor and three diodes compared with the switched‐inductor quasi‐Z‐source inverter (SL‐qZSI). The suggested inverter has a DC source ground point, continuous input current, and no start‐up inrush current. This proposed inverter compared with SL‐qZSI in the two investigated scenarios. Scenario 1: the proposed inverter has lesser capacitor voltage stress at the voltage conversion ratio than the voltage stress of SL‐qZSI, which results in lower DC‐link voltage. Scenario 2: the proposed inverter has higher voltage gain with respect to the SL‐qZSI, at the same input source and modulation index. Simulations are carried out using MATLAB/Simulink and compared with experimental ones, to show the validity and effectiveness of the proposed inverter. In order to estimate the losses and efficiency, calculations of power losses and efficiency of the ESL‐qZSI and SL‐ZSI are presented. Simulation and experimental results verify the effectiveness of the proposed inverter.

No abstract

In this paper, for high and low numbers of voltage levels, two new generalized multilevel converters are introduced, which comprise a six-switch H-bridge and several switched-source units. Switched-source units consist of bidirectional and unidirectional switches along with a dc voltage source. The two proposed topologies are compared with topologies based on the six-switch Hbridge, conventional H-bridge, and some new topologies regarding the number of switches, dc voltage sources, gate drivers, and per-unit voltage block on switches. The comparison results reveal the superiority of the proposed topology with low number of voltage level (LNL) and proposed topology with high number of voltage level (HNL) regarding the per-unit voltage block and number of elements, respectively. Thus, the proposed topologies lead to reduction cost and weight of system. Furthermore, for high number of levels, HNL topology is more appropriate than LNL topology and vice versa. The performances of the proposed 15-level LNL and 61-level topologies are simulated by MATLAB, and proposed 15-level LNL topology in producing all voltage levels is validated by experimental results. K E Y W O R D S asymmetric topology, grid connected, H-bridge, multilevel inverter, prototype

No abstract