The invention discloses an offshore energy island power supply
system and a working method thereof, and the
system comprises an
offshore wind power flexible DC sending-out device which is used for transmitting the
offshore wind power to an onshore
power grid through a
submarine cable; the on-island
hydrogen production
ammonia alcohol power supply device comprises a
direct current power supply device and an
alternating current power supply device, and the
direct current power supply device comprises an
energy storage type MMC converter, a
direct current side capacity type
energy storage device, a direct current side power type
energy storage device, a direct current side PEM
electrolytic cell, a direct current side alkaline
electrolytic cell, a distributed photovoltaic device, a distributed energy storage device and a
hydrogen production device which are connected with a direct current
bus. The alternating-current power supply device comprises an alternating-current side alkaline
electrolytic cell, an alternating-current side PEM electrolytic
cell and an alternating-current side capacity type energy storage and
ammonia alcohol preparation device which are respectively connected with an alternating-current
bus; the on-island
hydrogen production
ammonia alcohol power supply device is used for carrying out
hydrogen production ammonia alcohol operation through
offshore wind power and photovoltaic power. According to the embodiment, the
utilization rate of offshore
wind power is increased, the power supply efficiency is improved, and the service life of energy storage equipment is prolonged.