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This paper proposes a diamond‐shaped high step‐up switched‐capacitor based basic multilevel inverter topology. The basic switched‐capacitor (SC) stage consists of 2 active switches, 2 diodes, and 2 capacitors. Using a single DC source with the unfolding circuit (10 switches, 5 capacitors, and 5 diodes) results in the production of 17 voltage‐steps at the output with the gain of up to 8 times of the input voltage. By extending the diamond‐shaped switched‐capacitor stages, higher voltage levels and voltage gains can be possible. The suggested topology employs two half‐bridges (instead of a full‐bridge) to produce positive, zero, and negative steps, which reduces the Voltage Stress (VS) on two output switches and consequently reduces Total Voltage Stress (TVS). In addition, the natural voltage balancing of capacitors eliminates the need to an additional control circuitry and consequently reduces the total converter size, complexity, and cost. In addition, modularity, scalability, low voltage ripple on capacitors, low total voltage stress, high power quality, and capability of supplying low/medium power factor (R‐L) loads are some of the merits of the proposed topology. The low Cost Function (CF) obtained in the comparison section as well as experimental results verifies the advantages of the proposed topology.

Publisher Copyright: Author This paper suggests a single-input switched-capacitor Nine-level inverter configuration advantaging from quadruple voltage-boosting ability, natural voltage balancing of capacitors, and reduced components per level. Also, the single-source character of the proposed topology makes it cheaper and more compact. The cascaded version of the suggested topology has also been introduced, by which high boosting factors, as well as large number of steps, can be obtained. The proposed topology can effectively supply the resistive-inductive or pure inductive load types. The capacitors' impulsive-charging-current issue has been solved by simple small-inductance-based inductor-diode (L-D) networks. The comparative analysis affirms the fewer device-usage in suggested configuration per equal gain or level count than existed structures, resulting in less size and cost. The usage of Nearest-Level modulation guarantees the low-frequency operation of semiconductors and reduces the switching losses. The comparative analysis and experimental outcomes affirm the competitiveness and accurate functionality of suggested configuration.

In this paper, a developed structure is proposed for high step-up nonisolated noncoupled inductor based multiport dc–dc converters. The voltage gain per number of devices of the proposed topology is higher than that of similar topologies. This means that, by using the same number of devices, the proposed topology can generate higher gains than other structures. In other words, the proposed topology utilizes less number of devices for producing the same voltage gain, which leads to less total cost, size, weight, and complexity. Despite high voltage gain, the normalized peak inverse voltage (NPIV) on switches/diodes is low. Higher number of input ports leads to higher gains and lower NPIVs on devices. The load energy can be absorbed and stored in first input unit. Modularity, simple structure, continuous input currents, and low input current ripple are the other profits of proposed topology. Low/medium power applications are suggested for the proposed structure. Proposed topology has been explained and operational modes along with steady-state analysis have been discussed. For better verification, the proposed topology has been compared with several multiport high gain converters. Comparison results confirm the advantages of the proposed topology. Finally, the proper performance of the proposed topology has been validated by experimental results.

This article proposes a single-phase double-source 27-level basic inverter structure based on Switched-Capacitors (SCs) circuit for renewable energy sources. The extendibility, low Blocking Voltage (BV) on semiconductors, step-up capability, and self-voltage balancing of capacitors are the main advantages of the suggested basic structure. Using double H-bridges to generate bi-polar voltage waveform, the blocking voltage on the semiconductors limit to only 0.692 Vo,max. The Average of Normalized Blocking Voltage (ANBV) on semiconductors of basic topology is only about 33.52%. Two extended structures have been presented with higher output voltage steps and boosting factors. The first extended topology composed of two (right and left) Generalized Switched Capacitor based Modules (GSCMs), results in reduced sources (only 2), increased steps, low BV on semiconductors, and boosting factor of 2n (n: number of SC Cells). The second extended topology can be realized by applying more cascaded Switched-Capacitor Modules (SCMs), which benefits from quadruple-gain and increased levels (9m, m: number of cascaded modules). The suggested topologies properly supply the zero or low power-factor load types. The superiority of proposed configurations over recently presented similar structures has been compared and verified. The experimental outcomes of the basic topology have also been provided to validate its correct operation.

This paper suggests a Hybrid Switched-Capacitor 9-Level Boost Inverter (HSC9LBI) topology that provides quadruple voltage-gain. Capability of feeding zero or low power-factor load types as well as natural voltage balancing of capacitors are other merits of suggested HSC9LBI. Two half-bridges are utilized to create bipolar voltage-waveform. The suggested HSC9LBI requires single DC source, which results in compact size. Different operational modes have been elaborated. The comparison and simulations results have been presented to verify superiority and suitable functionality of suggested configuration.

In Quasi-Z Source (QZS) network is proposed that is suitable for Renewable Energy Systems (RESs). This high voltage lifting capability is provided by QZS network and quadratic structure. The input current waveform is continuous, which makes the suggested converter capable of Maximum Power Point Tracking (MPPT). So, this converter is a suitable choice for grid-connected RESs. Despite the transformerless conventional QZS converters that produce low voltage gain, the suggested converter has large gain. Easy control, simple configuration and low Normalized Blocking Voltage (NBV) are other advantages of suggested topology. The comparative and simulation outcomes approve effectiveness of suggested configuration.

This paper introduces a novel basic single-phase Switched-Capacitor Based Multi-Level Inverter (SCBMLI) topology that benefits from modularity, boosting capability, self-voltage balancing of capacitors and low Blocking Voltage ( $BV$ ) on switches. Due to application of developed H-bridge, only 2 switches ( $S_{2}, S_{5}$ ) experience maximum $BV$ , which leads to reduced Total Blocking Voltage ( $TBV$ ). The suggested basic topology employs only 2 DC sources, which remains constant at extended versions. The basic unit can be extended by increment of switched-capacitor cells to reach more steps and/or larger boosting factors. To verify different features of suggested topology, it has been contrasted with novel similar structures. Then correct performance of suggested topology has been certified by simulation results.

This paper suggests an improved basic single-phase 35-level inverter unit that consists of 4 DC power supplies, 4 capacitors, 10 switch/diodes and 10 gate driver circuits. The basic unit employs two DC links constructed by two cascaded capacitors in parallel with $V_{L}$ and $V_{R}$ DC sources. The use of capacitors not only has led to increased levels, but also has reduced the DC sources and converter cost. The voltage balancing of capacitors is done naturally which eases the control of proposed topology. Since, the proposed structure is based on developed H-bridge, it can produce positive, zero and negative voltage steps. Also, the suggested topology has suitable performance for resistive ( $R$ ) or resistive-inductive ( $R-L$ ) load types. Based on comparison results, the suggested structure has more steps per devices than similar configurations. The credits of suggested topology have been certified by comparisons and simulations in PSCAD/EMTDC software.

This study proposes a modular high voltage gain structure for non-isolated non-coupled inductor based multi-input (NINCIBMI) dc-dc converters. Proposed topology can produce higher voltage gains per number of components (switch, diode, capacitor and inductor) than other NINCIBMI topologies. In other words, the proposed topology uses less number of components for achieving the same voltage gain. This property can lead to reduced cost, size, weight and complexity of topology. Also, proposed topology benefits from continuous input current. Despite the high voltage gain of proposed topology, it has considerably low normalised voltage stress (NVS) on its switches/diodes. Another important advantage of proposed topology is that, as the number of input units increase, the voltage gain increases too, but the NVS on switches/diodes decreases. The proposed topology is suggested for low and medium power applications. The 2-input version of proposed topology has been studied in detail and different operational modes and steady-state analyses have been presented. For a better evaluation, proposed topology has been compared with recently presented novel multi-input high step-up structures. The 2-input version has also been experimentally implemented. Obtained results confirm appropriate performance of proposed topology.

Summary In this paper, a simple non-isolated multiple input (MI) bidirectional DC-DC topology is proposed which can operate in buck, boost, or buck-boost modes. The proposed topology utilizes a battery pack to realize the bidirectional power flow operation especially when the input sources are non-storable ones. The excess energy of input sources can be stored in the battery and be injected to the load, when required. Simultaneous or independent power transfer of input sources is also provided. For better evaluation, the proposed topology has been compared with several recently presented novel topologies, from view point of number of inductors, capacitors, switches, and diodes. Comparison results show that the proposed topology utilizes less number of components (switches, inductors, capacitors, and current sensors) which can reduce the size, cost, and complexity of converter. Different operational modes of the proposed topology (unidirectional buck, boost, buck-boost modes, and bidirectional mode) have been presented. Also, boost mode of the proposed topology has been investigated in detail, from design point of view, and generalized relationships have been proposed for calculation of critical inductance (CI) and output voltage ripple (OVR) of proposed n-input boost topology. To validate proposed theoretical concepts, the proposed topology has been modeled and simulated in PSCAD/EMTDC software, and the 3-input boost version has been experimentally implemented. Simulation and experimental results confirm appropriate performance of the proposed topology.

This study proposes an improved non-isolated single-inductor multiple-input buck DC–DC converter, with reduced number of components. Less component count can reduce the size, mass and cost of converter. Simultaneous or independent power transfer capability has been provided for input sources. The bidirectional power flow capability has also been provided through usage of a battery without any additional switches. This makes the topology very suitable for hybrid energy systems or hybrid electric vehicle/electric vehicle applications. Different operational modes of proposed topology have been presented. Then, a generalised relationship has been proposed for calculation of critical inductance (as an important design parameter) of proposed n-input buck topology. To make a better judgement, the proposed topology has been compared with recently presented novel topologies. Also, a simple proportional–integral based controller has been applied to regulate output voltage and assign the portion of power that each input source should provide. To confirm the validity of proposed topology and theoretical concepts, the three-input version has been modelled and simulated in PSCAD/EMTDC software and implemented experimentally. Simulation and experimental results validate proper performance of proposed topology.

In this paper, a developed single-phase basic 17-level inverter topology has been proposed that is based on Switched-Capacitor Cell (SCC). The proposed basic topology consists of a main unit and two SCCs. The proposed basic unit can be extended by increasing the number of SCCs on both sides of main unit that leads to entirely symmetric extended topology. Reduced device (DC source, switch, capacitor and, diode) count is the main advantage of proposed topology that results in less size, weight and cost. Application of two half-bridges instead of one full-bridge leads to less total standing voltage on the switches. Self-voltage balancing of capacitors, lesser cost function as well as high step-up capability is another main merits of proposed topology. Note that the self-voltage balancing property of capacitors discards the need for an extra complicated voltage regulation controller circuitry. Also, the proposed topology can successfully supply low power factor (R-L) loads. Simulations have been done in PSCAD/EMTDC software to verify the performance of proposed topology. The comparison and simulation results prove the superiority of proposed topology.

In this paper a developed quadratic based high step-up DC-DC topology has been proposed that can be extended to achieve higher voltage conversion ratios. Due to utilization of only one switch, there are only two modes of operation and only one gate driver circuit is required. These properties lead to simple control and low volume and expense of proposed topology. The suggested configuration has higher gain per number of devices in comparison with other similar structures, which can lead to reduced expense, volume and weight of converter. Also, the continuous input current of suggested configuration candidates it for Photo Voltaic (PV) applications, where the Maximum Power Point Tracking (MPPT) is essential. Modularity and low blocking voltage on switches/diodes are another advantages of proposed topology. The suggested topology has been compared with recently presented novel structures and simulated in PSCAD/EMTDC. The comparison and simulation results prove the correct operation and suitability of suggested configuration.

This paper proposes an enhanced basic 31-level inverter topology that can be expanded for achieving increased levels. The suggested basic topology is consisted of 4 input DC sources and 12 power switches. The magnitude of DC sources are selected in binary manner to minimize the redundant states and maximize the number of distinct voltage levels. The modular and simple structure, low average of voltages stress on switches, suitability for resistive-inductive load type as well as increased levels per device count (DC input sources, power switches and gate driver circuits) are the main advantages of suggested configuration. In this study, the suggested basic and extended topologies have been introduced and the relevant switching scheme has been presented. Then for better evaluation, the suggested basic topology has been compared with similar topologies and simulated in PSCAD/EMTDC software. The comparison and simulation results verify the effectiveness of suggested topology.

This paper suggests a new multi-phase dc-dc converter that benefits from modularity, simple control and structure, extra gain, continuous input current and low normalized voltage stress on switches/diodes. The suggested configuration can track the maximum power point in PV applications. The suggested configuration produces larger gains per device count, in comparison with other topologies. After introduction of suggested configuration, its operational modes have been explained. Then, its effectiveness has been verified by comparison and simulation results.

In this paper, a modified single-phase Multi-Level Inverter (MLI) is proposed that produces more steps per device count, which reduces less total expense, volume, weight and losses. The low Normalized Blocking Voltage (NBV) on switches is another advantage that results in reduced expense, volume and losses of switches and consequently higher efficiencies. Due to increased steps, the suggested configuration has low Total Harmonic Distortion (THD) and consequently high power quality. The proposed 49-level topology has been introduced, explained and compared with recently presented novel MLIs. For performance verification, the PSCAD/EMTDC has been used as simulation software. Comparison and simulation results approve the suitability of suggested configuration.

This paper suggests a novel dc-dc topology that produces extra high gains in mild duty cycles. The main profits of suggested topology are: simple control and structure, continuous input/output currents and low standing voltage of power switches/diodes. In this paper, the new structure is introduced and its operating principles and analysis are given. Then, the suggested configuration is compared with similar novel structures. Also, the proposed topology has been simulated in PSCAD/EMTDC software. The presented comparison and simulation results verify satisfactory operation of suggested converter.

This paper proposes a new topology for cascaded 35-level inverters. Higher number of produced levels (35 levels in this paper) improves the quality of output voltage and reduces its Total Harmonic Distortion (THD). For producing 35 levels, the suggested configuration employs less switches than similar structures. This means that the share of each switch in suggested configuration on generating voltage steps is more than that of similar structures. Reduction in switch count leads to reduced driver circuits and finally reduces the complexity, volume, weight and expense of suggested configuration. The fundamental frequency strategy has been applied for switching of proposed topology. The suggested configuration can be employed on supplying low/medium power factor (R-L) loads. The simulation results approve correct operation of suggested configuration.

This paper proposes a new high gain dc-dc converter. The proposed topology has simple control and structure. The input and output (load) current waveforms are continuous. The continuous character of input current of suggested converter candidates it as a suitable choice for application in renewable energy industry, where the Maximum Power Point Tracking (MPPT) can easily be achieved. Usually the transformerless converters suffer from low gain, but the suggested converter has extra high gain, in spite of its non-isolated and non-coupled inductor nature. The gain per number of elements in proposed topology is more than other similar topologies. Despite the high gain, the Normalized Voltage Stress (NVS) on switches/diodes of proposed topology is considerably low. In this paper, the proposed topology has been introduced and its operational modes have been explained. The steady state analysis have also been presented. To assess the proposed topology, it has been contrasted with similar novel topologies. Comparison results validate the advantages of proposed topology. The obtained simulation results (done in PSCAD/EMTDC) confirm the effective operation of proposed topology.

A new step-up Cascaded Multi-Level Inverter (CMLI) has been proposed in this paper. The proposed basic 35-level topology is composed of 4 DC sources, 2 capacitors, 2 diodes and 12 switches. The sum of input DC sources is 10V dc , where the peak output voltage is 17V dc . So, the proposed basic topology can act a step-up inverter with the gain of about 1.7. The proposed basic topology has simple structure. Since the voltage balancing of capacitors are done naturally, the control of proposed topology is also simple. The number of levels per number of components (such as DC sources, switches, gate driver circuits, diodes and capacitors) in proposed basic topology is higher than other similar converters. In this paper, the proposed basic topology has been introduced and its operational principles have been presented. Then, it has been compared with recently presented novel structures. The comparison results validate the advantages of proposed basic topology. Then, the proposed basic topology has been extended to act as a Multi-Level inverter. Finally, the appropriate performance of proposed basic topology has been verified by simulation results, extracted from PSCAD/EMTDC software.

This paper proposes a double-input high voltage gain topology for Non-Isolated Non-Coupled Inductor (NINCI) based de-de converters. The proposed topology is capable of producing high voltage gains, while the Normalized Voltage Stress (NVS) on the switches/diodes remain low. Simple structure, continuous input currents and also the low current ripple of input sources are the advantages of proposed topology. The low/medium power applications are suggested for the proposed topology. In this paper, different operational modes and also steady state analyses of proposed topology have been presented. To verify effectiveness of proposed topology, it has been modeled and simulated in PSCAD/EMTDC software. Simulation results validate efficient performance and suitability of proposed topology.

A 15-level flying capacitor multi-cell based inverter with new control method is proposed. The main benefit of this topology is minimising the number of components (switches, insulated-gate bipolar transistor (IGBTs), diodes, flying capacitors and DC sources with minimum variety number) that are used for producing the same number of output voltage levels. The proposed novel control strategy is capable of regulating voltage of flying capacitors on desired values, which results in increased number of output voltage levels. Another feature of the proposed control strategy is robustness against the load changes. Moreover, a new algorithm is presented for determining the voltage rating of flying capacitors. Simulations carried out in PSCAD/EMTDC software package and the experimental data were validated against numerical results.

In this paper, an improved Cascaded Multi-Level Inverter (CMLI) topology which can be "symmetric" or "asymmetric" is proposed. The improved topology can produce higher number of levels using lower number of components. Higher number of levels leads to generation of a high quality with low Total Harmonic Distortion (THD) output voltage waveform. To increase number of voltage levels, two algorithms are proposed for determination of magnitude of dc voltage sources, which are investigated and the most effective one is introduced. To verify operation of proposed topology, it is modeled and simulated in PSCAD/EMTDC software. Proper performance of proposed topology is confirmed by obtained simulation results.

In this paper, two types of DC-DC converters with modified structures and different control methods for generating AC output voltage are proposed. In the modified cascaded dual buck inverter, absence of split capacitors leads to increased reliability of the inverter. Also, a new structure is proposed for integrated dual buck-boost inverter. The proposed inverters are capable of obtaining maximum power from solar cells by themselves. To evaluate operations of the proposed inverters, they have been modeled and simulated in PSCAD/EMTDC for different modulation indexes. Simulation results confirm validity and effectiveness of the proposed inverters.