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In this paper, an improvisation of cross-connected sources based multilevel inverter (CCS-MLI) topology is presented in terms of maximization of levels. The proposed modified CCS-MLI will boost the output levels with the addition of one bidirectional switch in the existing CCS-MLI. The proposed modified topology lowers the switches number, diodes, gate drivers, dc power supplies, size, installation area and the cost of the system in comparison with conventional topologies and existing CCS-MLI. Working of the proposed topology is presented through a mathematical modelling and switching table. Finally, to confirm the effective performance of the proposed topology, simulation results by MATLAB/simulation and experimental results are given. [ABSTRACT FROM PUBLISHER]

Multilevel inverter (MLI) is gaining rapid popularity in high/medium power applications due to low THD and high quality output waveform. Recently, the MLI topologies with reduced part count has attracted the researchers by offering higher number of output voltage level with reduced part count as compared to classical topologies (CHB, NPC and FC). It is observed that these recently proposed topologies are aimed to increase the output level with less number of components but the discussion over their suitability for a particular application is not yet explored completely. The main purpose of this paper is to provide an instructive review and analysis of existing MLIs with reduced part count. An exhaustive comparison of MLIs are assessed based on the number of switches, standing/blocking voltage across the switches, conduction losses, switching losses and cost. With the outcome of comparison results, suitable structure of MLI can be judged with reduced number of components and losses for given applications. [ABSTRACT FROM AUTHOR]

Multilevel inverters have created a new wave of interest in industry and research. While the classical topologies have proved to be a viable alternative in a wide range of high-power medium-voltage applications, there has been an active interest in the evolution of newer topologies. Reduction in overall part count as compared to the classical topologies has been an important objective in the recently introduced topologies. In this paper, some of the recently proposed multilevel inverter topologies with reduced power switch count are reviewed and analyzed. The paper will serve as an introduction and an update to these topologies, both in terms of the qualitative and quantitative parameters. Also, it takes into account the challenges which arise when an attempt is made to reduce the device count. Based on a detailed comparison of these topologies as presented in this paper, appropriate multilevel solution can be arrived at for a given application. [ABSTRACT FROM AUTHOR]

This paper presents a multilevel inverter that has been conceptualized to reduce component count, particularly for a large number of output levels. It comprises floating input dc sources alternately connected in opposite polarities with one another through power switches. Each input dc level appears in the stepped load voltage either individually or in additive combinations with other input levels. This approach results in reduced number of power switches as compared to classical topologies. The working principle of the proposed topology is demonstrated with the help of a single-phase five-level inverter. The topology is investigated through simulations and validated experimentally on a laboratory prototype. An exhaustive comparison of the proposed topology is made against the classical cascaded H-bridge topology. [ABSTRACT FROM PUBLISHER]

As multilevel inverters are gaining increasing importance, newer topologies are being proposed to reduce part count for large number of levels in output voltage. A simplified five-level inverter has been recently reported in the literature to reduce component count. The topology comprises of floating input DC sources connected in opposite polarities through power switches. The structure requires lesser active switches as compared with conventional cascaded H-bridge topology with much reduced switching losses. Available literature present generalisation of the topology with symmetrical sources, but no investigations are made for equal load sharing and asymmetrical configurations. This study presents a comprehensive analysis of the aforementioned topology, referred to as cross-connected sources-based multilevel inverter (CCS-MLI). The topology is analysed for both symmetric and asymmetric source configurations. Also, a new algorithm for asymmetric source configuration suitable for CCS-MLI is proposed. A control scheme is also proposed for equal load sharing in five-level topology. Investigations are made for possibility of equal load sharing in higher level structures and fundamental frequency switching of switches bearing higher voltage stresses. Various concepts are verified with simulations and experimental studies. [ABSTRACT FROM AUTHOR]

Abstract: Suitable integration of more than one energy sources is an interesting and challenging task that attracts attention of the researchers. Integration of several energy sources profoundly depends on the power electronic converters which interface multiple energy sources having different V–I characteristics. Therefore, suitable integration and better utilization of energy source demands, well designed and efficient interfacing circuitry. In this paper, a non isolated multiple source DC/DC converter (MSC) is proposed. The generation of MSC using pulsating source cells as a building block has been discussed briefly. The proposed converter is proficient for energy diversification from renewable and storage energy sources individually or simultaneously. It has the capability to operate either in buck, boost or buck–boost mode of operation with possibility of bidirectional power flow. It offers simplicity in structure with inherent bypass circuit, flexibility in control scheme and reliability in operation. In addition, a power management control algorithm for proposed converter has also been discussed. The proposed concept has been investigated through detailed device level simulation using MATLAB/Simulink environment. Experimental implementation and validation have been carried out on a low power prototype using digital signal processor (DSP) TMS320F2812. [Copyright &y& Elsevier]

Abstract: Recently multilevel inverters are gaining popularity due to reduced voltage stress across power switches and low total harmonic distortion (THD) output voltage waveform. However, device count increases with increased voltage levels. This paper presents a novel multilevel topology which is capable of obtaining all additive and subtractive combinations of input DC levels in the output waveform. Though all such levels can be obtained using the proposed topology, the actual number of levels depends on the DC source arrangement. A comparison is made between proposed topology and the classical multilevel topologies on the basis of device count and number of levels in the output voltage waveform. A detailed study of the proposed topology is presented through the example of a nine-level inverter. Appropriate modulation scheme is also presented. The proposed concept is analyzed through simulation studies and verified experimentally. [Copyright &y& Elsevier]

This paper presents a new topological structure for symmetrical cascaded multilevel inverters. The proposed circuit consists of cross-connected separate symmetrical DC sources which can generate number of levels equal to that of a cascaded H-bridge topology with reduced number of power switches. It is especially suitable for utility interfacing of renewable energy sources. It also offers the possibility of a transformer less and filter less operation. The working principle of the proposed topology is explained with the help of a single-phase five level inverter. Simulation results are obtained in matlab/simulink environment and are verified experimentally on a laboratory prototype. An exhaustive comparison of the proposed topology is made with the classical cascaded H-bridge topology, especially with the considerations of conduction losses and cost-effectiveness. The proposed topology results in the reduction of number of power switches, losses, installation area, and converter cost and thus can be implemented as an effective and efficient power electronic interface for renewable sources of energy with the utility grid. [ABSTRACT FROM AUTHOR]