Inverters have played a fundamental role in the development of energy conversion, especially in industrial applications. Over time, new architectures have been developed to optimize performance and reduce energy losses. Among the alternatives are dual inverters, which offer greater control flexibility, improve output wave quality, and, most importantly, have a greater impact on reducing energy consumption. Therefore, this study aims to systematically review and classify the main dual inverter topologies and modulation strategies, evaluating their advantages, limitations, and potential applications in industrial systems.

This paper presents a symmetry-based analysis applied to a dual-inverter system that powers different types of loads. The configuration consists of two three-phase inverters controlled using carrier-based space-vector pulse-width modulation (CBSV-PWM). The study investigates how the phase-shift angle α between the two inverters influences multilevel voltage synthesis and the resulting electrical behavior of the system. The main contribution is the systematic characterization of the complementary angular symmetry between phase-shift α and 360°-α, establishing their relationship with the differential output-voltage magnitude and the resulting voltage and current waveforms. The complete phase-shift range from 0° to 360° is evaluated to identify the evolution of the synthesized voltage and the symmetry between complementary operating points. Resistive, resistive–inductive, and induction-motor equivalent loads are considered to examine the influence of the load characteristics on the system response. PSIM simulation results show that complementary phase-shift pairs exhibit closely corresponding voltage behavior, while the maximum differential-voltage magnitude occurs around α = 180°. The results demonstrate that the phase-shift angle provides a systematic means of characterizing the voltage-synthesis behavior of the dual-inverter configuration and its complementary angular symmetry under different load conditions.