An LCC-S Compensated Wireless Power Transfer System with Dual Switch-Controlled Capacitors for Multi-Frequency Receivers

In the one-to-many transmission system, the inverter needs to change the operating frequency to achieve the selectivity towards the secondary coils. However, the fixed compensation parameters cannot guarantee that the system maintains constant current output at multiple operating points. This paper proposes a novel LCC-S WPT system based on Switch-Controlled Capacitor (SCC). By introducing SCC into the LCC network, variable capacitance can be obtained, so that the parameters of the compensation network can be adjusted synchronously according to the changes of the operating frequency, which means that the transmitter coil is always maintained constant current output. After introducing the LCC parameters tuning method, a 300W prototype with 50mm gap was fabricated and tested. The experimental results prove the feasibility of the selectivity of this system.