A Hybrid LCC-SP Compensation Network With Adjustable Impedance Angle Used for Single-Stage Wireless Power Transfer

In order to realize constant current output (CCO) and constant voltage output (CVO) in single-stage wireless power transfer (WPT), this article proposes a hybrid LCC-series–parallel (LCC-SP) compensation network with adjustable impedance angle. The switching between CCO and CVO could be realized by changing the parameters of the circuit rather than changing the structure of the circuit, which cause fewer influence on the circuit when the operation mode switches. Due to the structure of the proposed compensation network, the hybrid LCC-SP compensation network could isolate the dc component in a single-stage WPT converter, which is caused by an asymmetric modulation strategy to ensure that the loosely coupled transformer works normally. Zero-voltage switching (ZVS) can be realized by adjusting the impedance angle. Moreover, the current of primary coil could keep constant, which can be used to protect the primary converter when the secondary coil is moved accidentally. Also, the transfer gain of the proposed compensation network does not rely on the transformer parameters; more parameters design freedom can be realized. The few passive devices are used in this circuit for higher efficiency and lower cost. Finally, the superiorities of the proposed circuit are verified by experiments.