This webinar will compare the power-transfer efficiency of two wireless charging architectures. We will also propose a standard method for measuring total system efficiency and provide some insight on the major power losses of the two systems.

Wireless chargers are basically power supplies; and the most important measure of quality for a power supply is efficiency. This key measure is generally expressed as efficiency versus load current or output power. This is a well-accepted approach when the load conditions are well-defined and because users (typically engineers) can effectively apply these data to a specific application. However, this approach has less value in a wireless charging application because there are different and uncontrolled variables that impact system efficiency (spatial positioning, for example) and because there is no standard to describe at which points the measurements should be made. This lack of an industry measurement approach can lead to end-user confusion or worse; it can obfuscate actual power-transfer performance.