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Multilevel inverters are increasingly being employed for industrial applications, such as speed control of motors and grid integration of distributed generation systems. The focus is on developing topologies that utilize fewer lower-rating switches and power sources while working efficiently and reliably. This work pertains to developing a three-phase multilevel inverter that employs switching capacitors and a single DC power supply that produces a nine-stage, three-phase voltage output. A recently proposed powerful meta-heuristic technique called symbiotic organism search (SOS) has been applied to identify the optimum switching angles for Selective Harmonic Elimination (SHE) from the output voltage waveform. A thorough converter analysis has also been done in the MATLAB/SIMULINK environment and is validated with the real-time hardware-in-the-loop (HIL) experiment results. [ABSTRACT FROM AUTHOR]

Recent research has focused on sustainable development and renewable energy resources, thus motivating nonconventional cutting-edge technology development. Multilevel inverters are cost-efficient devices with IGBT switches that can be used in ac power applications with reduced harmonics. They are widely used in the power electronics industry. However, under extreme stress, the IGBT switches can experience a fault, which can lead to undesirable operation. There is a need for a reliable system for detecting switch faults. This paper proposes a signal processing method to detect open-circuit problems in IGBT switches. Relative wavelet energy has been used as a feature for a machine learning algorithm to diagnose and classify the faulted switches. The switching sequence can be altered to restore a healthy output voltage. Inverter faults have been diagnosed by using support vector machine (SVM) and decision tree (DT), and an ensemble model based on decision tree (DT) and XG boost algorithm was developed, which yielded 92%, 88%, and 94.12% accuracy, respectively. [ABSTRACT FROM AUTHOR]

The extensive employment of power semiconductor devices in multilevel inverters (MLIs) has the consequence of increased failure probabilities. With numerous applications demanding highly reliable inverters, several fault-tolerant schemes have been devised to address switch open-circuit faults. This paper analyzes a multilevel inverter topology for IGBT modules undergoing open-circuit faults, a major impediment to reliable operation within a power converter. Reconfiguration of modulation is performed post-fault. A modulation scheme is implemented across failure modes as a hybrid of nearest level control and selective harmonic elimination. Reliability assessment of the topology is performed, including a comparison with previous literature in terms of component requirements and reliability. Simulation results validate the proposed solutions. [ABSTRACT FROM AUTHOR]

Implementing voltage boost multilevel inverter topologies for PV and fuel cell energy sources is highly advantageous. Switched-capacitor multilevel inverters (SCMLI) have a step-up feature with low device requirements and can remove the need for high gain dc-dc converters leading to reduced overall system bulk. This work proposes a dual input SCMLI to achieve an output of nineteen levels while using a low number of components and high boosting factor and self-balancing of capacitor voltages. A comprehensive analysis of the proposed structure is presented, focusing on component requirements, cost and dynamic performance. The efficiency and loss distribution during operation is also provided. The operation and real-time performance of the SCMLI have been verified by simulation. Experimental results further validate the simulation results. [ABSTRACT FROM AUTHOR]

This paper presents the Archimedes optimization algorithm to eliminate selective harmonics in a cascaded H-bridge (CHB) multilevel inverter (MLI). The foremost objective of the selective harmonic elimination (SHE) is to eliminate lower order harmonics by finding the optimal switching angle combination which minimizes the objective function containing Total Harmonic Distortion (THD) and other specific harmonic terms. Consequently, the THD is also reduced. In this study, a recently proposed metaheuristic technique named the Archimedes optimization algorithm (AOA) is used to determine the optimal angles corresponding to the 5, 7 and 9 level CHB-MLI. AOA involves equations related to a physical law, the Archimedes Principle. It is based on the idea of a buoyant force acting upward on a body or object that is partially or completely submerged in a fluid, and the upward force is related to the weight of the fluid displaced. This optimization technique has been implemented on CHB-MLI to generate various level outputs, simulated on MATLAB™ R2021a version environment software. The simulation results reveal that AOA is a high-performance optimization technique in terms of convergence speed and exploitation-exploration balance and is well-suited to the solution of the SHE problem. Furthermore, the laboratory validated the simulation result on a hardware setup using DSP-TMS320F28379D. [ABSTRACT FROM AUTHOR]

In this letter, constraints solving of selective harmonic elimination equation using minimum number of switching pulses for modified packed U‐cell five‐level inverter is employed, and the optimum angles for total harmonic distortion (THD) reduction are found using genetic algorithm (GA). The novel constraints‐based GA algorithm is applied in this work, which eliminates the third and its higher orders and fifth harmonic in the output voltage waveform. The obtained results are compared with the those of conventional approach wherein the THD obtained for each order is displayed. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

Summary: Multilevel inverters have been the vital component for the power electronic systems and have been researched extensively to further enhance their performances in terms of topology and their control. In this paper, a new bidirectional single‐phase multilevel inverter module has been proposed with a reduced number of switches along with lower voltage stresses. The proposed module generates 17 levels at the output with 10 unidirectional switches along with four dc voltage sources with two varieties of dc voltage sources. Moreover, for a higher number of levels, the cascade connection of several modules has been discussed in this paper with three different methods for the selection of dc voltage sources. The proposed module has been compared with several similar topologies, which set the benchmark of the proposed one. The operation and performance of the proposed module have been validated through several simulation and experimental results with different types of load considering a change of modulation index. [ABSTRACT FROM AUTHOR]

High gain DC-DC converters are needed to step up the low voltage generated from distributed generation (DG) sources. Many topologies of these converters which are proposed in the literature are not suitable for renewable applications because they lack common ground and low ripple continuous input current. High voltage gain, common ground structure and continuous input current with low ripple are inherent advantages of the converter proposed in this paper. The suggested converter has other attractive features like lower voltage stress on semiconductor devices, high gain per inductor and simple control. The gain and efficiency of the converter are also calculated in non-ideal conditions. In the lab, the prototype of the proposed converter with a power rating of 200 W is being constructed to check and verify the functionality of the proposed converter both in steady-state and dynamic conditions. The highest efficiency of the proposed converter is found to be 95.10% which is greater than traditional and other converters listed in literature. The converter has been found to function effectively in open-loop conditions and produces significant voltage gain at lower duty cycles. [ABSTRACT FROM AUTHOR]

Switched capacitor-based multi-level topologies have recently gained attention due to their inherent technical superiority suitable for renewable-based applications. In this work, a single-phase boosting nine-level inverter is proposed, which employs a DC-source ( V dc ) and three capacitors. It uses 14 switches that require nine independent control signals from the controller, conducts a maximum of 8 switches at any instant and provides a 9-level quadruple-boosted output voltage. The proposed topology is verified for an experimental setup's steady and transient load conditions. A detailed discussion on the balanced charging of the capacitors is also presented. A novel harmonic elimination-based-nearest level modulation scheme is proposed, wherein the simplified control scheme of the nearest level control is extended to eliminate the undesired low-order harmonics from the output voltage waveform of the 9-level inverter. Moreover, its merits of a simplified control, lower power loss, reduced total voltage stress and enhanced voltage gain are discussed in comparison with various 9-level inverters in detail. [ABSTRACT FROM AUTHOR]

In this paper, a new high‐gain quadratic boost DC‐DC converter is proposed for a DC microgrid. The converter has a voltage multiplier cell made up of switched inductors to obtain a high voltage at the output. It has a common ground and continuous input current, which makes the converter feasible for renewable energy and DC microgrid applications. The proposed topology consists of a single switch which makes the control simple. The converter achieves a gain of four times the traditional quadratic boost converter and can also operate in continuous and discontinuous conduction modes. The voltage stress across the switch and all the other passive components is less than the output voltage. The variation of voltage gain in the case of parasitic resistances is also shown. The reliability analysis of the proposed converter using Markov modeling is also presented by considering both open‐circuit and short‐circuit faults across the semiconductor devices. A 200 W prototype of the converter is also prepared and the hardware results of the converter are also presented in the paper. The converter operates at high efficiency of 96% at 100 W output power operation. The variation of reliability with different converter parameters like the duty cycle and the input voltage is also discussed in the paper. The experimental results in fault conditions are also shown. [ABSTRACT FROM AUTHOR]

An innovative multilevel inverter (MLI) relying on switched capacitor (SC) architecture is suggested for single-phase inverters with 13-levels. This suggested SCMLI is expected to be capable of generating output AC voltages at appropriate levels while utilizing fewer switches. The suggested inverter utilizes two count of capacitors, two asymmetrical dc sources, two diodes, and 11 switches. As fewer switches are needed, fewer gate drivers are also needed, increasing the converter's power density. The challenge of preserving self-voltage balance across the capacitors in an SC-MLI circuit is yet another task. Additionally, when the modulation index is low, self-voltage preservation is subpar. It is possible to maintain the self-voltage balance with the capacitors connected in this suggested SC-MLI avoiding the requirement of any ancillary devices or challenging control schemes. Regardless of the modulation index values, capacitors operate at self-balanced levels in all regions of the spectrum. The suggested SC-MLI has a strong ability to achieve good power quality and can balance capacitor voltages even at low modulation indices. The suggested SC-MLI is first modelled using different loading conditions in the MATLAB/Simulink® platform, and subsequently it is validated with the help of typhoon-HIL real-time emulator. Using the simulation tool PLEXIM-PLECS, the suggested inverter's overall switching losses and efficiency are estimated and found out to be 95.87%. [ABSTRACT FROM AUTHOR]

Multilevel converters have gained significant popularity in medium-voltage and high-power applications due to their numerous advantages over traditional two-level converters. These advantages include reduced harmonic distortion, improved efficiency, and lower stress on power semiconductors. Selective harmonic elimination (SHE) is a modulation method that can be employed with multilevel converters to achieve high-quality output voltage waveforms. In this work, an extension of Broyden's method, known as the Quasi-Modified Newton Method, is implemented for selective harmonic elimination and accurate calculation of switching angles for a wide range of modulation indices. The proposed method is applied to cascaded H bridge inverters operating at levels 5, 7, and 9. The method offers simplicity, reduced computational burden, and faster convergence, making it easily implementable, reducing total harmonic distortion (THD), and reducing RMSE and MAD errors. The paper includes simulation and experimental results that validate the accuracy and effectiveness of the proposed approach., (© 2024. The Author(s).)