Purpose

This paper aims to propose a new MLI topology with reduced number of switches for photovoltaic applications. Multilevel inverters (MLIs) have been found to be prospective for renewable energy applications like photovoltaic cell, as they produce output voltage from numerous separate DC sources or capacitor banks with reduced total harmonic distortion (THD) because of a staircase like waveform. However, they endure from serious setbacks including larger number of capacitors, isolated DC sources, associated gate drivers and increased control difficulty for higher number of voltage levels.

Design/methodology/approach

This paper proposes a new three-phase multilevel DC-link inverter topology overpowering the previously mentioned problems. The proposed topology is designed for five and seven levels in Matlab/Simulink with gating pulse using multicarrier pulse width modulation. The hardware results are shown for a five-level MLI to witness the viability of the proposed MLI for medium voltage applications.

Findings

The comparison of the proposed topology with other conventional and other topologies in terms of switch count, DC sources and power loss has been made in this paper. The reduction of switches in proposed topology results in reduced power loss. The simulation and hardware show that the output voltage yields a very close sinusoidal voltage and lesser THD.

Originality/value

The proposed topology can be extended for any level of output voltage which is helpful for sustainable source application.

中文翻译：

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一种新的三相多电平直流链路逆变器拓扑结构，减少了光伏应用的开关数量

目的

本文旨在为光伏应用提出一种减少开关数量的新 MLI 拓扑。多电平逆变器 (MLI) 已被发现可用于光伏电池等可再生能源应用，因为它们从众多独立的直流电源或电容器组产生输出电压，并且由于阶梯状波形而降低了总谐波失真 (THD)。然而，它们承受着严重的挫折，包括大量的电容器、隔离的直流电源、相关的栅极驱动器以及更高数量的电压电平的控制难度增加。

设计/方法/方法

本文提出了一种新的三相多电平 DC 链路逆变器拓扑，以克服前面提到的问题。所提出的拓扑设计用于 Matlab/Simulink 中的五级和七级，使用多载波脉冲宽度调制进行门控脉冲。显示了五级 MLI 的硬件结果，以证明所提议的 MLI 在中压应用中的可行性。

发现

本文在开关数量、直流电源和功率损耗方面对所提出的拓扑与其他传统和其他拓扑进行了比较。建议拓扑中开关的减少导致功率损耗降低。仿真和硬件表明，输出电压产生非常接近的正弦电压和较小的 THD。

原创性/价值

所提出的拓扑结构可以扩展到任何有助于可持续电源应用的输出电压水平。