A Novel Approach for Single-Source 3-Phase 7-level Boost Inverter

In this article, a 3-phase inverter with a voltage gain of three demonstrated via the toggle capacitor concept.It synthesizes a line voltage waveform with seven levels. The most salient feature of this topology is that a single input DC locate is necessaryfor the 3-phase implementation.Each branch of the proposed topology requires eight power electronics switches and 2condenser. The opposite of the current reach their highest across the energyoutlet is equal to the value of the input DC voltage. The capacitors are all self-balanced at all modulation indices. The proposed approach minimizes the cost function to 5.429, as the proposed topology exhibits better topological characteristics mainlythe boosting-factor, overall-voltage and component..Topology with similar features, however, has a const function of 7.333. In addition, the suggested topology is highly modular, so the amount of pole energyscalescould be increased by further adding switched capacitors, and the same arm structures can be used for all phases. However, an important limitation is that the pole voltage is unipolar, and therefore redundant states in phase are not available, although they are readily available in line voltage. The 7-level topology and modulation procedure are verified by result discussion, which represents that with a DC energy of 100 V, a 3-phase voltage with about 300 V could be obtained in equal steps of 100 V, while the pole voltage is a unipolar 4-level peak value 300V in equal steps of 100V

Generalized diamond‐type single DC‐source switched‐capacitor based multilevel inverter with step‐up and natural voltage balancing capabilities

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

A modular switched-capacitor multilevel inverter featuring voltage gain ability

This paper proposes a modular switched-capacitor multilevel inverter with single dc source, which can obtain triple voltage gain by using two capacitors. It is worth noting that the inherent inversion capacity eliminates the Hbridge, which can effectively reduce the voltage stress of switches, and the maximum voltage stress (MVS) of all switches is kept within 2Vdc. In addition, the proposed inverter is able to integrate inductive load, and the capacitor voltage self-balancing can be achieved without any auxiliary circuits. Moreover, the modular inverter also has expandable structure which can generate more output levels and raise the voltage gain by employing multiple switchedcapacitor cells, meanwhile the MVS for all of the switches is kept within 2Vdc in the extended structure. Furthermore, comprehensive analysis and comparison with other multilevel inverter have been implemented to evaluate the superiority of the proposed topology. Finally, the steadystate and dynamic performance of the proposed inverter is validated through a seven-level inverter prototype, the correctness and feasibility of the proposed topology are verified by simulations and experiments

A nine-level switched-capacitor step-up inverter with low voltage stress

This paper proposes a nine-level switched-capacitor step-up inverter (9LSUI) which can achieve a quadruple voltage gain with single dc source. Differing from other switched-capacitor inverters, the voltage stress of switches is effectively reduced due to the elimination of H-bridge, and the peak inverse voltage of all switches is kept within 2Vdc. In addition, the proposed inverter is able to integrate inductive load, and the capacitor voltage self-balancing can be achieved without any auxiliary circuits. Moreover, the topology structure can be flexibly extended to raise the output levels, and the peak inverse voltage of switches can remain constant with the increase of sub-modules in the extended structure. Comprehensive comparisons are performed to verify the outstanding advantages of the proposed inverter. Finally, the steady-state and dynamic performance of the proposed inverter is validated through an experimental prototype, and the experimental results are provided to prove the theoretical analysis

Symmetric and Asymmetric Multilevel Inverter Topologies With Reduced Device Count

In this work, two new topologies of single-phase hybrid multilevel inverters for symmetrical and asymmetrical configurations are presented for use in drives and control of electrical machines and the connection of renewable energy sources. The proposed topology uses 2 dc sources, 12 switches, 1 flying capacitor, and 3 diodes to generate boosted 13-levels and 17-levels for symmetric and asymmetric configuration, respectively. Self-voltage balancing of its capacitor voltage regardless of load type, load dynamics, or modulation index is a key advantage of the suggested design. The higher performance of proposed topologies in terms of the total number of switches, TSV, THD, switch stress, and dc sources are demonstrated by comparing those with recently published topologies. In addition, a widely employed nearest level control modulation approach is used to provide output voltage levels with low THD. Finally, experiments were undertaken to validate the performance of the suggested topology. 2013 IEEE.This work was supported in part by Qatar University Research Grant from Qatar University, Doha, Qatar, under Grant QUCP-CENG-2020-2 and Grant QUCP-CENG-2022-571; and in part by the Qatar National Library, Doha.Scopu

A T-type switched-capacitor multilevel inverter with low voltage stress and self-balancing

This paper proposes a novel T-type multilevel inverter (MLI) based on the switched-capacitor technique. The proposed inverter not only achieves that the maximum voltage stress of the switches is less than the input voltage but also has a voltage boost capability, which makes it suitable in high voltage applications. It is worth mentioning that the proposed inverter features two topology extension schemes which help it achieve a higher output level and voltage gain. With the merit of low voltage stress and reduced power devices, a seven-level inverter can be achieved using only two capacitors. Moreover, capacitor voltage self-balancing capability can simplify the complexity of the circuit and control. The topology, operating principle, modulation strategy and analysis of the capacitor of the inverter are presented. The superiorities of the proposed inverter are investigated by comparing with recently proposed hybrid MLIs and switched-capacitor MLIs. Finally, a seven-level prototype is constructed to validate the correctness of the theoretical analysis and the feasibility and effectiveness of the proposed inverter