A wireless power receiver for wirelessly receiving a supply of power from a wireless power supplier is disclosed. The wireless power receiver includes a power reception unit for wirelessly receiving wireless power from the wireless power supplier; a rectifier for rectifying the wireless power into power including a DC waveform; a power adjustor for configuring a closed loop with the power reception unit for a first period and transferring the wireless power to the rectifier for a second period to adjust a size of the wireless power; and a controller for determining the first period and the second period, wherein the power adjustor is electrically connected to the power reception unit and the rectifier.