This paper presents a new transformer-less switched-capacitor (SC)-based five-level gridconnected inverter with inherent voltage-boosting capability. The proposed topology achieves a voltage gain factor of two without requiring an additional DC-DC boost converter or transformer, resulting in a more compact, cost-effective, and efficient design. A single SC cell is utilized to perform bidirectional capacitor charging during both positive and negative grid half-cycles, thereby improving energy transfer efficiency and significantly reducing capacitor size and volume compared to conventional topologies. The inverter employs a minimal number of components - only nine switches and one flying capacitor - while maintaining high performance. Only five switches operate at high frequency, which reduces switching losses, gate driver complexity, and electromagnetic interference (EMI). A straightforward control strategy ensures that the inverter delivers a high-quality sinusoidal current waveform to the grid and supports both active and reactive power flow under various power factor conditions. The reliability of the proposed inverter is analyzed, and its performance is validated through detailed simulations and experimental results. A comparative study with existing solutions highlights the advantages of the proposed topology in terms of efficiency, voltage gain, component count, and waveform quality.

Switched capacitor multilevel inverter topologies are attractive among industrial power electronics researchers due to their applicability in sustainable energy systems such as renewable energy source (RES) applications. In this paper, a new switched capacitor (SC)-based grid-tied seven-level inverter is proposed for renewable energy sources (RES) applications. The proposed inverter can generate a seven-level output voltage waveform with voltage boosting ability and a gain factor of 3. Also, the proposed topology can provide the self voltage balancing for capacitors. The most important challenge of the SC-based topologies, i.e., the capacitor charging spike current, is solved by applying a soft charging circuit in the charging loop of the capacitors. The soft charging circuit consists of an inductor and a power diode in the capacitor charging path. Using a small size inductor in the soft charging circuit, the proposed inverter can limit the input current spikes. Comprehensive experiment results and comparisons are presented to verify the accurate performance of the proposed inverter.