Phase Synchronization and Magnitude Control With Interference Between Transmitters in Wireless Power Transfer

With coupling between transmitter (TX) coils, the weakly activated TX experiences interference current (INTC) from adjacent strong TX. The strong interference has prohibited the magnitude and phase control. We reveal two operating modes (called negative and positive) that simultaneously achieve magnitude and phase control of TX coil currents. The negative mode is for TX, which is a victim of strong INTC originating from adjacent TX. This mode is chosen when the target level of TX coil current is lower than the interference level. At such mode, its inverter voltage should be significantly delayed with respect to adjacent TX to maintain phase synchronization and interference regulation. On the other hand, the positive mode is chosen when the target level of TX coil current is higher than INTC. Hence, the proposed controller first chooses one of the two modes depending on the target magnitude of TX coil currents. The phase of two TX coil currents is synchronized and their magnitude ratio is regulated to the coupling ratio even with strong interference level. No additional power components or radio-frequency (RF) communication is required. High cross coupling between TXs is tolerable, increasing the flexibility in coil geometry.