Continuous traction power supply systems that incorporate interconnected substations throughout the entire traction network are poised to become a next-generation traction power supply mode. This system fundamentally relies on various types of converters, including three-phase-to-single-phase converters (Shu et al. 2013; Liu 2010; Chen et al. 2016; Xia 2017; Li et al. 1988; He et al. 2013b; Sun et al. 2017; Li 2010). A brief overview of a continuous traction power supply system, which consists of two substations interconnected and operating in a three-phase-to-single-phase topology, is illustrated in Fig. 2.1. At Substation 1 and Substation 2, high-power power electronic converters are connected to the three-phase power grid and single-phase traction network, on both sides, respectively. These converters are capable of controlling the ports—managing voltage amplitude, frequency, and phase—which facilitates the interconnection on both ends of the three-phase power grid and the single-phase traction network. The two-way flow of energy between the traction network and the three-phase grid, achieved through power control, enables not only power supply to the loads in the traction network from the three-phase power grid but also the feedback of traction braking energy to the three-phase power grid for consumption.