DETECTING METHOD AND POWER TRANSMITTER IN WIRELESS CHARGING SYSTEM

The embodiments of the present application provide a detecting method and a power transmitter in a wireless charging system. The power transmitter includes: a signal sampling circuit, configured to sample a signal generated by an oscillation circuit of the power transmitter; and a control circuit, coupled to the signal sampling circuit, configured to: obtain an oscillation waveform based on the obtained sampled values; perform an integral operation on the oscillation waveform and average the result of the integral operation to obtain an integrated average value; obtain a oscillation frequency of the oscillation waveform; and determine whether there is a foreign object or a power receiver approaching the power transmitter, based on the integrated average value and the oscillation frequency. The power transmitter can effectively improve the accuracy of determining whether there is a foreign object or a power receiver approaching the power transmitter.