Dual-source 17/25-Level ANPC inverter with low stress on devices and reduced part count suitable for hybrid energy systems

This paper proposes a unity-gain active-neutral-point-clamped (ANPC) multilevel inverter topology utilizing two DC sources, ten switches, and four DC-link capacitors. The proposed inverter generates 17 and 25 output voltage levels by leveraging input voltage ratios of V₂ = 3V₁ (triple) and V₂ = 5V₁ (quintuple), respectively. Unlike conventional designs, the topology eliminates the need for an H-bridge to produce bipolar voltage waveforms, thereby reducing the number of switches exposed to the maximum output voltage from four (in H-bridge-based structures) to two. Additionally, the inverter supports diverse load types across a wide range of power factors. Comparative analysis demonstrates that the proposed topology achieves the lowest number of conducting switches (only three) to generate any output voltage level, minimizing voltage drop, device losses, and conduction losses while enhancing overall efficiency and output voltage quality. Furthermore, it requires fewer DC sources and switches compared to existing 25-level inverters. Experimental results from a laboratory-scale prototype validate the effective operation of the proposed ANPC inverter in both 17- and 25-level configurations.