Offshore wind power has the advantages of abundant resources and broad utilization prospects, and it is also of great significance for China to achieve “dual-carbon” goal. The tight space layout, harsh environment, and complicated operation and maintenance conditions of deep and distant sea offshore platforms require higher requirements for lightweighting, compactness, and reliability of voltage source converter based high voltage direct current (VSC-HVDC) converter stations. For the offshore wind power transmission system via VSC-HVDC, 6.5 kV power devices are used to reduce the construction cost and equipment footprint, and improve the transmission capacity per unit volume. A compact and lightweight VSC-HVDC power module is designed based on a 6.5 kV integrated gate commutated thyristor (IGCT), which improves the stability of the IGCT black start circuit and verifies its reliability through experiments, providing technical support for subsequent development.