This paper presents a generalized structure of a new three-phase multilevel inverter (MLI) which ensures better performance with the minimum number of components for different applications including DC power supply-based renewable energy sources. The proposed MLI topology is developed in the form of several basic blocks which are individually made of a DC voltage source and a semiconductor switch. All the balanced DC sources required for the proposed inverter are made through a high-frequency magnetic link. The single–phase and three-phase five level (5-L) inverters with the rating of 3.5 and 100 kVA, respectively, are simulated, while a five level (5-L) single-phase inverter is implemented for demonstrating the switching strategy and different operational modes. The rigorous calculations are presented to determine switching losses and conduction losses which are minimum because only three conducting switches are responsible for generating each voltage level during every operating mode. The structure of the aforementioned inverter provides optimized value of total standing voltage (TSV = 5.5V_dc with 5-L single-phase leg) of the system. The proposed inverter offers energy conversion efficiency of 94.84% for 5-L single-phase leg which is significantly enhanced and it also minimizes the equipment ratings as well as overall costs of the entire system.

本文介绍了一种新型三相多电平逆变器（MLI）的通用结构，该结构可确保以最少的组件数量为不同应用（包括基于直流电源的可再生能源）提供更好的性能。提出的MLI拓扑以几个基本模块的形式开发，这些基本模块分别由DC电压源和半导体开关组成。拟议的逆变器所需的所有平衡直流电源均通过高频磁链实现。模拟了分别额定功率为3.5 kVA和100​​ kVA的单相和三相五电平（5-L）逆变器，同时还采用了五电平（5-L）单相逆变器来演示开关策略和不同的操作模式。提出了严格的计算方法来确定最小的开关损耗和传导损耗，因为在每个工作模式期间，只有三个传导开关负责产生每个电压电平。前述逆变器的结构提供了总站立电压的最佳值（TSV = 5.5V _dc与5 L单相支路）。拟议的逆变器为5升单相桥臂提供94.84％的能量转换效率，这一效率得到了显着提高，并且还使设备额定值以及整个系统的总成本降至最低。