Magnetic Field Tuning and Control for Wireless Power Transfer Using Inductive Tuning Plunger and Conical Coils

Multiple input wireless power transfer (WPT) system has drawn increased interests recently due to its enhancing ability to the efficiency of power transfer. In most cases, it uses a number of transmitters to deliver the wireless power efficiently. These transmitters can be massively used to harvest energy as much as possible and therefore reduces signal and link losses. Powering many devices using massive number of transmitters allows cross coupling occurring. In particular, signals or magnetic fields are mutually induced between transmitters. The goal of this work is to provide an efficient link for wireless power transfer and compensate for the impact of cross coupling. A tuned technique is proposed to optimize the transmit signal for a conical coil transmitter. The proposed scheme efficiently delivers the wireless power by controlling the beam of the magnetic flux. By using this new technique, we then increase the main loop gain of the wireless power signal and reduce the back gain for the receiver in such region. The results are compared to the conical coil. In addition, results illustrate that a tuned transmitter controls the magnetic flux pattern for efficient wireless power transfer.