Effects of 7-level ANPC SiC Inverter on Motor Stator insulation and Cable insulation in an Electric Ship Propulsion Drive

Advent of Wide band-gap (WBG) SiC and GaN devices has revolutionized the All Electric Ship (AES) technology as they provided a major push to move from conventional 2-level inverters towards multilevel inverters. WBG multilevel inverters facilitate high voltage, high-frequency operation and improve the performance of shipboard electric systems. However, their effect on insulation systems needs to be explored to better plan and design electric drives for longer durability and reliability. This paper investigates the effect of a 7-level active neutral point clamped (ANPC) SiC multilevel inverter on medium voltage cable insulation and motor stator ground-wall insulation. The simulation of ANPC is done in ANSYS Twin Builder. The dielectric stress and leakage currents in the cable and motor stator-insulation system have been analyzed in ANSYS Maxwell.