Three-Phase Three-Level Phase-Shifted PWM DC–DC Converter for Electric Ship MVDC Application

A three-phase three-level phase-shifted pulsewidth modulation (PSPWM) dc-dc converter is proposed for electric ship medium-voltage direct current application. Output voltage is controlled by incorporating PSPWM. Gate signals of each phase are phase shifted by 2π/3 from each other. This results in a decrease in output voltage ripple. Major features of the converter include: 1) good dynamic performance under low switching frequency; 2) fault tolerance capability; and 3) plug and play capability. In order to obtain behavioral and performance characteristics of the proposed converter, detailed analytical and hardware in loop simulation studies are carried out. Finally, the viability of the scheme is confirmed through detailed experimental studies on a MW level, 1-kHz prototype developed for the purpose.