Modular multilevel converters (MMCs) represent one of the multilevel converter structures currently under extensive research and application (Shu et al. 2013). With advantages such as compact structure and easy extensibility, these converters have been widely studied and implemented in various fields, including high-voltage, high-power, large-capacity reactive power compensation (Ambrozic et al. 2003) and DC power transmission (Shu et al. 2011; Xing 2016). These systems are typically based on a three-phase-to-three-phase configuration (Liu 2007). However, traction networks, which generally operate in a single-phase configuration, require a single-phase bridge arm output from MMCs. Given the current lack of studies on three-phase-to-single-phase converters based on MMCs, further research is needed, particularly regarding applications in continuous traction power supply scenarios.