Wireless Power Supply for Small Household Appliances Using Energy Model

In order to resolve the safety and stability of the power supply for household appliances, a system of wireless power supply for household appliances with Bluetooth communication based on electromagnetic resonance is proposed. In this paper, the energy model of wireless power transfer system is first proposed, which is based on the circuit equations and variable substitution, more accurate than the coupled-mode model and simpler than the circuit model. Then, the characteristics of output power and transfer efficiency of the wireless power transfer system are analyzed, and a system of wireless power supply for small household appliances has been designed and implemented. Furthermore, Bluetooth communication is applied to achieve various protection functions of the system, therefore enhancing the safety and stability of the system. Experimental results show that this power supply system achieves a stable output dc voltage of 48 V and a large output power of 100 W, the total efficiency is more than 80% within a distance of 30 cm.