WIRELESS CHARGING DEVICE, AND POSITION DETECTION METHOD AND SYSTEM

This application discloses a wireless charging apparatus, a position detection method, and a system. The apparatus includes a transmit end or a receive end. The transmit end includes a transmit end resonant network and an inverter circuit, and the transmit end resonant network includes a transmitting coil. The receive end includes a receive end resonant network and a rectifier circuit, and the receive end resonant network includes a receiving coil. The receive end further includes an auxiliary coil. During wireless charging, a voltage at both ends of the auxiliary coil is generated by a current of the transmitting coil. The apparatus further includes a controller. The controller is configured to obtain a relative position between the transmit end and the receive end based on a self-inductance of the transmitting coil and at least one of the following parameters. The at least one parameter includes one or two of a coupling coefficient between the transmitting coil and the auxiliary coil and a coil mutual inductance between the transmitting coil and the auxiliary coil. There is a single change relationship between the at least one parameter and the relative position. Therefore, the relative position between the transmit end and the receive end of wireless charging can be accurately detected.