A wireless charging receiving apparatus, comprising a receiver coil, a rectifier, and a controller, wherein the receiver coil is configured to receive electromagnetic energy transmitted by a transmitter coil and output an alternating current; the rectifier comprises at least two controllable switches, and is configured to rectify the alternating current from the receiver coil to a direct current by using the at least two controllable switches; the controller is configured to perform phase-locking on a phase of a current fundamental component of the alternating current received by the rectifier, to obtain a periodic signal having a same frequency as the current fundamental component; and the controller is further configured to: generate a synchronization reference signal having the same frequency as the periodic signal, generate drive signals of the controllable switches in the rectifier based on the synchronization reference signal, and control, based on the drive signals, the controllable switches in the rectifier to convert the alternating current into the direct current, wherein the drive signals and the current fundamental component have the same frequency, wherein that the controller is configured to perform phase-locking on a current fundamental component to obtain a periodic signal is specifically: the controller is configured to obtain a phase difference between a current fundamental component and an initial preset periodic signal that are of a first round of phase-locking; the controller is configured to perform low-pass filtering on the phase difference, perform proportional-integral control on a phase difference obtained after the filtering to obtain a first period value, and obtain, based on the first period value, a periodic signal corresponding to the first round of phase-locking, wherein the first period value is inversely proportional to the phase difference; and in a non-first round of phase-locking, the controller is configured to compare a periodic signal of a previous period that is obtained after phase-locking with a current fundamental component of a present period, to obtain a periodic signal of the present period. the receiver coil is configured to receive electromagnetic energy transmitted by a transmitter coil and output an alternating current; the rectifier comprises at least two controllable switches, and is configured to rectify the alternating current from the receiver coil to a direct current by using the at least two controllable switches; the controller is configured to perform phase-locking on a phase of a current fundamental component of the alternating current received by the rectifier, to obtain a periodic signal having a same frequency as the current fundamental component; and the controller is further configured to: generate a synchronization reference signal having the same frequency as the periodic signal, generate drive signals of the controllable switches in the rectifier based on the synchronization reference signal, and control, based on the drive signals, the controllable switches in the rectifier to convert the alternating current into the direct current, wherein the drive signals and the current fundamental component have the same frequency, wherein that the controller is configured to perform phase-locking on a current fundamental component to obtain a periodic signal is specifically: the controller is configured to obtain a phase difference between a current fundamental component and an initial preset periodic signal that are of a first round of phase-locking; the controller is configured to perform low-pass filtering on the phase difference, perform proportional-integral control on a phase difference obtained after the filtering to obtain a first period value, and obtain, based on the first period value, a periodic signal corresponding to the first round of phase-locking, wherein the first period value is inversely proportional to the phase difference; and in a non-first round of phase-locking, the controller is configured to compare a periodic signal of a previous period that is obtained after phase-locking with a current fundamental component of a present period, to obtain a periodic signal of the present period. the controller is configured to obtain a phase difference between a current fundamental component and an initial preset periodic signal that are of a first round of phase-locking; the controller is configured to perform low-pass filtering on the phase difference, perform proportional-integral control on a phase difference obtained after the filtering to obtain a first period value, and obtain, based on the first period value, a periodic signal corresponding to the first round of phase-locking, wherein the first period value is inversely proportional to the phase difference; and in a non-first round of phase-locking, the controller is configured to compare a periodic signal of a previous period that is obtained after phase-locking with a current fundamental component of a present period, to obtain a periodic signal of the present period.