Abstract : This paper elucidates the principle of a unit-series multilevel phase-shifting PWM voltage source inverter, introduces the simulation modeling process of the multilevel inverter, and explains the encapsulation, parameter meaning, and parameter settings of pulse modules, single-unit modules, single-phase modules, and three-phase frequency conversion drive systems. This provides valuable reference for the development and research of new power electronic devices. It demonstrates that the unit-series multilevel high-voltage inverter has low harmonic pollution, high input power factor, and good output waveform, eliminating the need for input harmonic filters and power factor compensation devices. This provides meaningful guidance for production practice and has significant practical implications for the localization of high-voltage inverters. Keywords : Unit-series multilevel; High-voltage inverter; Simulation; Modeling 1 Overview High-voltage inverters are specialized electrical appliances that realize stepless speed regulation of high-voltage motors, meeting the speed control requirements of motors in production processes. Their widespread application is of great significance for improving product quantity and quality, saving energy, and reducing costs. While IGBT frequency converter technology is relatively mature for capacities below 500kW, in high-power, high-frequency, and high-voltage applications, single IGBT devices cannot meet the voltage withstand requirements due to the high voltage. Some large international companies have been striving to adopt series technology, connecting multiple IGBTs in series to meet the high-voltage requirements of motors. This necessitates "voltage equalization technology" in the system, but the inherent characteristics of the devices make this technology difficult to implement, hindering the development of high-voltage, high-power IGBT frequency converters. Later, a multi-level circuit structure emerged that avoids the need for voltage equalization technology, solving the high-voltage, high-power problem. For multi-level structures, high-voltage frequency converters can also be implemented as long as the low-voltage frequency converter technology is mastered. This breakthrough has provided a significant impetus for electrical drives, breaking the long-standing slow progress in the field of high-power frequency converters. Simulation studies can simplify the structure of new devices and shorten development costs, making them an essential process in scientific research. This paper utilizes the simulation tool MATLAB to conduct a simulation study of a 6kV high-voltage frequency converter. It introduces the simulation modeling process of a multi-level frequency converter, explaining the encapsulation, parameter meaning, and parameter settings of pulse modules, single-unit modules, single-phase modules, and three-phase frequency conversion drive systems within the converter. The introduction of multi-level frequency converter modeling methods and techniques provides valuable reference for the development and research of new power electronic devices. Simulation results also demonstrate that the high-voltage frequency converter has low grid pollution and a high input power factor, eliminating the need for input harmonic filters and power factor compensation devices. This provides meaningful guidance for production practice and has significant practical implications for the localization of high-voltage frequency converters. [b][align=center]For more details, please click: Simulation Modeling of a Unit Series Multi-Level High-Voltage Frequency Converter[/align][/b]