Adaptive Frequency Control in a Wireless Power Transfer System Using RF Modules

This paper presents an adaptive frequency control method for wireless power transfer systems, which monitors the resonant frequency variations caused by changing operating conditions and guarantees optimal system performance. The system is evaluated both at fixed frequency and with the proposed adaptive control approach in a simulation environment. It is then physically designed and tested. The simulation results show that the system automatically adapts to the resonance condition at different winding distances with adaptive frequency control, and higher output power is obtained compared to the fixed frequency structure. In the tests performed on the physical prototype, lower power transfer was observed compared to the simulation due to the low voltage components and application-specific mounting, alignment, and environmental effects. The developed system is also capable of wireless control of a door lock mechanism through a radio frequency communication based, battery-free portable controller. The results show that adaptive frequency control provides significant advantages in terms of energy efficiency and power transfer in wireless power transfer systems.