Wireless power transmitter with receiver overvoltage protection, controller and method

The invention provides a wireless power transmitter with receiver overvoltage protection, a controller and a method. The wireless power transmitter comprises: a power stage circuit comprising a plurality of switches coupled to a resonant transmitting circuit, where the resonant transmitting circuit comprises a transmitting coil and a resonant capacitor coupled to each other; the transmitting controller is used for controlling the power level circuit to convert an input power supply to generate a driving power supply according to a pulse width modulation control signal when a corresponding wireless power receiver is close to the resonant transmitting circuit, and the driving power supply drives the resonant transmitting circuit to generate a wireless transmitting power supply; therefore, the corresponding wireless power receiver is wirelessly supplied with power. When the change rate of a driving current of the driving power supply to time exceeds a change rate threshold value, an operation parameter of the po