A new rectifier with combined power flow control capability for a series-tuned inductive-power-transfer receiver

A new rectifier with combined power flow control capability has been developed to simplify a series-tuned power receiver in inductive power transfer (IPT) applications. Since the traditional IPT receiver usually employs two separate stages (rectifier and power flow regulator) after the tuning circuit to obtain a required DC output voltage, the receiver circuit is often complicated and large. A big DC inductor often needs to be used in the power flow regulator, which further increases the size of the receiver circuit, especially for heavy current applications, because the DC inductor is often the largest component in such a circuit. The proposed rectifier using two MOSFETs and one blocking diode in a series-tuned IPT receiver eliminates the DC inductor, and a new control strategy with combined rectification and power flow control is developed to further reduce the complexity and size of the power receiver. The theoretical analysis of the proposed rectifier has been verified by simulation and experimental study, and a prototype series tuned power receiver has been built to receive about 50 watts of power when it is coupled to a push-pull resonant transmitter. The overall power efficiency of the full system has reached about 80%.