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This letter presents an improved hybrid active neutral point clamped (IHANPC) five-level (5L) inverter as an upgrade/replacement for a conventional 5L ANPC inverter. Unlike the conventional ANPC inverters, the proposed inverter doubles the utilization of the dc-link voltage, eliminating the need for an additional boosting stage. By charging the switched capacitor (SC) to half the input voltage, it doubles the rms output voltage for a given dc voltage. Also, a tiny inductor is incorporated to limit the prevailing SC impulse charging current without affecting the inverter operation. Moreover, the proposed IHANPC inverter can also self-start and self-balance the voltages of the SC and the dc-link capacitor voltages without any external circuits or balancing techniques. Due to the lower required dc-link voltage and limited SC charging current, devices with lower voltage and current ratings can be selected. Design considerations and a comparative analysis with other current topologies are discussed in detail. The comparison shows that the proposed IHANPC requires the least number of parts to achieve the same performance and output quality. To validate the effectiveness and practicality of the proposed IHANPC inverter, the experimental results for a 1.2-kW system are presented.

This article proposes a compact five-level common-ground-type inverter with inherent boosting capability. Due to the common ground feature, the leakage current is eliminated, making it suitable for solar photovoltaic applications. The distinctive features of the proposed inverter are that it employs two switched capacitors rated for only half of the output voltage with self-voltage balancing ability, which reduces the inverter's size, cost, and complexity. In addition, the proposed topology has the lower component count, the lower total standing voltage, a low dv/dt, lower number of conducting devices, and reduced capacitor voltage diversity factor as compared with its counterparts. The circuit description and operating principle are discussed in detail. Furthermore, the proposed and state-of-the-art topologies are compared with highlight their pros and cons. Further, a discussion of additional features, such as the cost and volume requirements, addresses the usefulness of the proposed topology in practical situations. Finally, experiential results are presented for grid-connected operation of the proposed topology, so as to validate its feasibility.

This letter proposes a novel switched-capacitor (SC) multisource boosting multilevel inverter featuring common ground connection for photovoltaic (PV)-dominated high-frequency ac applications. The proposed topology requires only eight switches, two diodes, and two SCs for generating a nine-level output voltage. The proposed topology has the ability to accommodate two PV sources while ensuring near zero ground leakage current. With the series/parallel technique, the SCs are self-voltage balanced, achieving sensor-less operation. The devised structure has the lowest conduction losses due to reduced number of conducting devices at each level. Furthermore, switching losses are reduced since fewer devices transit at any level as compared to the state-of-the-art topologies. A comprehensive comparative assessment of the proposed topology is carried out and included to highlight its beneficial features against the counterparts. The experimental evaluation of the proposed inverter topology is carried out and the results are presented to validate its feasibility and operability.