A power adapter configured to output a voltage of a pulsating waveform to charge a battery of a device in an intermittent manner, comprising: a first rectification unit, configured to rectify, in a charging process, an input alternating current and output a voltage of a first pulsating waveform; a switch unit and a transformer, configured to receive the voltage of the first pulsating waveform output by the first rectification unit and couple the voltage of the first pulsating waveform to a secondary side to generate an output voltage of the power adapter, wherein a first winding of the transformer is coupled to the output of the first rectification unit; a control unit, configured to acquire status information of the device to control the charging process, wherein the switch unit is configured to modulate the voltage of the first pulsating waveform according to a control signal, the transformer is configured to output a voltage of a second pulsating waveform based on the modulated voltage of the first pulsating waveform, the first rectification unit being connected to a primary winding of the transformer without electrolytic capacitor; a second rectification unit, configured to rectify the voltage of the second pulsating waveform and output a voltage of a third pulsating waveform; a first charging interface coupled to the second rectification unit without electrolytic capacitor, the first charging interface being configured to apply the voltage of the third pulsating waveform to a battery of a device via a second charging interface of the device when the first charging interface is coupled with the second charging interface, wherein the second charging interface is coupled with the battery; and a sampling unit, configured to sample an output voltage and an output current of the second rectification unit to obtain a sampling voltage value and a sampling current value; the control unit coupled with the sampling unit and the switch unit respectively, the control unit being configured to output the control signal to the switch unit to adjust a duty ratio of the control signal based on the sampling voltage value and the sampling current value, enabling the voltage of the third pulsating waveform to meet charging requirements of the device, wherein the sampling unit comprises: a first current sampling circuit, configured to sample a current output from the second rectification unit to obtain the sampling current value; and a first voltage sampling circuit, configured to sample a voltage output from the second rectification unit to obtain the sampling voltage value. a first rectification unit, configured to rectify, in a charging process, an input alternating current and output a voltage of a first pulsating waveform; a switch unit and a transformer, configured to receive the voltage of the first pulsating waveform output by the first rectification unit and couple the voltage of the first pulsating waveform to a secondary side to generate an output voltage of the power adapter, wherein a first winding of the transformer is coupled to the output of the first rectification unit; a control unit, configured to acquire status information of the device to control the charging process, wherein the switch unit is configured to modulate the voltage of the first pulsating waveform according to a control signal, the transformer is configured to output a voltage of a second pulsating waveform based on the modulated voltage of the first pulsating waveform, the first rectification unit being connected to a primary winding of the transformer without electrolytic capacitor; a second rectification unit, configured to rectify the voltage of the second pulsating waveform and output a voltage of a third pulsating waveform; a first charging interface coupled to the second rectification unit without electrolytic capacitor, the first charging interface being configured to apply the voltage of the third pulsating waveform to a battery of a device via a second charging interface of the device when the first charging interface is coupled with the second charging interface, wherein the second charging interface is coupled with the battery; and a sampling unit, configured to sample an output voltage and an output current of the second rectification unit to obtain a sampling voltage value and a sampling current value; the control unit coupled with the sampling unit and the switch unit respectively, the control unit being configured to output the control signal to the switch unit to adjust a duty ratio of the control signal based on the sampling voltage value and the sampling current value, enabling the voltage of the third pulsating waveform to meet charging requirements of the device, wherein the sampling unit comprises: a first current sampling circuit, configured to sample a current output from the second rectification unit to obtain the sampling current value; and a first voltage sampling circuit, configured to sample a voltage output from the second rectification unit to obtain the sampling voltage value. a first current sampling circuit, configured to sample a current output from the second rectification unit to obtain the sampling current value; and a first voltage sampling circuit, configured to sample a voltage output from the second rectification unit to obtain the sampling voltage value.