Systems for tuning a wireless power transfer system are provided, which may include any number of features. In one embodiment, a TET system includes a receive resonator is adapted to be implanted in a human patient and is configured to receive wireless power from a transmit resonator. The system can include a controller configured to identify if a foreign object is interfering with the transmission of power or generating an induced voltage in the receive resonator. The controller can also be configured to control the transmit resonator to phase match with the foreign object. Methods of use are also provided.