Multilevel inverter plays an important role in the field of modern power electronics and is widely being used for many high voltage and high power industrial and commercial applications. The objective of this paper is to design and simulate the modified asymmetric multilevel inverter topology with reduced number of switches. The proposed inverter topology synthesizes 21-level output voltage during symmetric operation using three DC voltage sources and twelve switches 8 main switches and 4 auxiliary switches. The different methods of calculating the switching angles are presented in this paper. The MATLAB/Simulink software is used to simulate the proposed inverter. The performance of the proposed inverter is analyzed and the corresponding simulation results are presented in this paper.

This paper proposes a new symmetric extendable type multilevel inverter topology suitable for medium and high voltage applications. The proposed inverter can produce output levels with a lower number of power switches. The main feature of the proposed inverter is the inbuilt creation of negative voltages without any supplementary circuit. Another advantage include the lower number of conducting switches which reduces the switching losses. Comparison study is presented between the proposed inverter and other recently presented topologies. Simulation results for 7 -level and 11 - level inverter operation are presented to show the performance of the proposed inverter topology.

Permanent magnet synchronous generator (PMSG)-based wind turbine systems have a wide range of applications, notably, for higher-rated wind energy conversion systems (WECS). A WECS involves integrating several components to generate electrical power effectively on a large scale due to the advanced wind turbine model. However, it offers several glitches during operation due to various factors, notably, mechanical and electrical stresses. This work focuses on evaluating the mechanical and electrical characteristics of the WECS using two individual schemes. Firstly, wind turbines were examined to assess the vibrational signatures of the drive train components for different wind speed profiles. To apply this need, acoustic sensors were employed that record the vibration signals. However, due to substantial environmental impacts, several noises are logged with the observed signal from sensors. Therefore, this work adapted the acoustic signal and empirical wavelet transform (EWT) to assess the vibration frequency and magnitude to avoid mechanical failures. Further, a matrix converter (MC) with input filters was employed to enhance the efficiency of the system with reduced harmonic contents injected into the grid. The simulated results reveal that the efficiency of the matrix converter with input filter attained a significant scale of about 95.75% and outperformed the other existing converting techniques. Moreover, the total harmonic distortion (THD) for voltage and current were examined and found to be at least about 8.24% and 3.16%, respectively. Furthermore, the frequency and magnitude of the vibration signals show a minimum scale for low wind speed profile and higher range for medium wind profile rather than higher wind profile. Consolidating these results from both mechanical and electrical characteristics, it can be perceived that the combination of these schemes improves the efficiency and quality of generated power with pre-estimation of mechanical failures using acoustic signal and EWT.

Multilevel inverters offers less distortion and less electro-magnetic interference compared with other conventional inverters and hence, it can be used in many industrial and commercial applications. This paper analyze the performance of the modified single phase seven level symmetrical inverter using minimum number of switches. The proposed topology consists of six switches and two dc sources, and produces seven level output voltage waveform during symmetric operation. The cost and size of the propsoed inverter minimum as it uses minimum number of components, The performance of the proposed multilevel inverter is analysed for different switching angles and the corresponding simulation results are presented. The simulation of the proposed inverter is carried out using MATLAB/Simulink software.