Dual-Transmitter Inductive Power Transfer System with Improved Misalignment Tolerance and High Compatibility with Different-Sized Receivers

A dual-transmitter inductive power transfer system featuring two concentric transmitter coils is proposed for low-power systems where compatibility with different-sized receivers and good misalignment tolerance are required. By incorporating two decoupled TXs into one single unit, the proposed scheme achieves better power and efficiency performance under a lower bill-of-materials cost compared to using two individual TXs, especially when the RX coil is small and the coil misalignment is large. Both TXs are energized using independent inverters and the inverter output voltages are regulated in accordance with the coupling condition to maximize the system efficiency. Superiority of the dual-TX system over single-TX systems is proved by experimental results.