Techniques for wireless power transfer are disclosed. An example of an apparatus for receiving power in a wireless power transfer system includes a power receiving element, a tuning and current doubler circuit operably coupled to the power receiving element, a power flow controller circuit operably coupled to the tuning and current doubler circuit, and a controller operable coupled to the power receiving element and the power flow controller circuit and configured to detect a signal in the power receiving element and to synchronize the power flow controller circuit based on the signal.