POWER SUPPLY DEVICE AND CHARGING CONTROL METHOD

A power supply device includes a transformer, a first rectifier, a voltage conversion module, and a control unit. The first rectifier is connected to a primary winding of the transformer, converts a received alternating-current voltage to a first direct-current voltage. The transformer is configured to convert the first direct-current voltage to a second direct-current voltage. The voltage conversion module is connected to the secondary winding of the transformer and configured to convert the second direct-current voltage to output a third direct-current voltage. The control unit, connected to the voltage conversion module, controls the voltage conversion module to adjust an output voltage or an output current of the power supply device.