The Switched Z-Source Inverter (S-ZSI) utilizes passive and active elements in the Z-source network, enabling the implementation of various switching methods. Although numerous papers have been published on the analysis and study of Z-source inverters, the impact of different control and switching methods on the performance of a single structure has not been comprehensively discussed and compared.

This paper presents a comparative study of three different switching methods (conventional PWM, modified sinusoidal PWM, and high-frequency switching method) applied to a single S-ZSI structure. The research precisely analyzes and compares the effect of changing the switching pattern on key parameters, including voltage boost factor, inductor current ripple, voltage and current stress on the switches, switching losses, Total Harmonic Distortion (THD), and the dynamic behavior of the system.

The results indicate that each switching method produces distinct performance characteristics, and the selection of the appropriate method depends on the specific application requirements. The paper first provides a comprehensive theoretical analysis of the S-ZSI operation in steady-state conditions. Then, the different switching methods are introduced, and the performance features of each method are examined when applied to the switched Z-source inverter structure. A comparative analysis of the three methods from various aspects is presented. Finally, to validate the theoretical analysis, simulation results for each of the proposed methods are provided in the PSCAD/EMTDC software environment.