A New Asymmetric Cascaded Multilevel Converter Topology With Reduced Voltage Stress and Number of Switches

Abstract

This paper presents a new structure of a multilevel inverter with fewer components, which is suitable for renewable energy sources and industrial loads applications. The structure has three unequal input sources and ten switches that can generate a 15-level output voltage. Furthermore, it can be connected in cascade for increasing, even more, the number of levels and output voltage. The main feature of the proposed inverter is its very low harmonic distortion at the output voltage and current due to the control method, which is based on the nearest level control method for generating a high-quality output voltage. A typical application of this inverter is in solar cells and wind turbines. Both simulations in Matlab/Simulink and experimental results in a scaled-down prototype validate the proposed theoretical analysis.INDEX TERMS Multilevel inverter, cascading converters, low harmonics, losses, distortion.

Design and implementation of isolated multilevel inverter with lower number of circuit devices

“…The proposed 15-level converter offers a voltage gain of 7, which is the highest among the reported 15-level topologies in [18][19][20][21][22][23][24][25][26][27][28]. It is visible from Table 3 that the topolo-gies suggested in [15,[18][19][20][21][22][23] require more than one input dc voltage sources. The staircase output can be produced without a capacitor in case of topologies suggested in [18,19,21] and [23].…”

“…However, the voltage gain of these converters is reduced, which limits voltage boost action of these converters. The proposed 15‐level converter offers a voltage gain of 7, which is the highest among the reported 15‐level topologies in [18–28]. It is visible from Table 3 that the topologies suggested in [15, 18–23] require more than one input dc voltage sources.…”

“…It is visible from Table 3 that the topolo-gies suggested in [15,[18][19][20][21][22][23] require more than one input dc voltage sources. The staircase output can be produced without a capacitor in case of topologies suggested in [18,19,21] and [23].…”

“…To overcome TBL issue, MLIs family employs multi‐input dc sources to obtain asymmetrical and symmetrical topologies. In [18] and [19] a 15‐level inverter is reported which require three dc input voltage sources. Although these topologies require fewer components, but the BF achieved is not economic due to use of more number of dc input sources.…”

A Review on Multilevel Inverter Topologies

“…As a consequence, there is less leakage current throughout the inverter's operation and the proposed topology and its modulation method can be utilized to generate more electricity. In [46], a novel MLI topology using fewer components was suggested, as shown in Figure 11. It can also be linked in a cascade to increase the number of levels of voltages at the end.…”