Development of a foreign object detection and analysis method for wireless power systems

In recent years, increased wireless power transfer systems technology research has led to systems with higher efficiency and more applicability over varying distances. Safety concerns associated with the technology are still challenges of major concern to the technology´s expansion and adoption. Selective and qualitative detection of foreign objects around the system (metallic or magnetic objects) is of key importance due to their ability to absorb energy from the wireless power supply field in the form of heat (parasitic heating) and possibly become a hazard. This paper presents the development and experimental validation of the Power Loss Detection method (PLD). The algorithm was developed using mathematical regression analyses on experimental data to co-relate parameters obtained from analytic approximations of power in the system. The method developed is demonstrated by test data to be an effective method for analyzing wireless power systems for foreign object differentiation and detection. This method overcomes the disadvantages of cost, thermal regulation, response time, and size that plague other foreign object detection and parasitic heating sensing techniques.