Power supply device, power supply system and data center

The invention provides a power supply device, a power supply system and a data center. The power supply device comprises a power input end; the first rectifier is coupled with the power supply input end and is used for converting first alternating current provided by the power supply input end into first direct current; the first direct current/direct current converter is coupled with the second end of the first rectifier and is used for converting the first direct current into second direct current; the first energy storage unit is coupled with the first direct current/direct current converter and is used for storing energy for the second direct current; the first inverter is coupled with the first rectifier and is used for converting the first direct current into second alternating current; the high-frequency transformer is coupled with the first inverter and is used for converting the second alternating current into third alternating current; the second rectifier is coupled with the high-frequency transfor