Relation Between Operation Frequency Range and Coupling Coefficient Variations in WPT Under Subresonant Frequency Control

A number of applications such as wireless EV charging introduce operational frequency range constraints such as those present in the SAE J2954 protocol. This paper analyzes the coupling coefficient variations limit of a constant voltage fed sub resonant frequency-controlled S-S IWPT link with a constant voltage load operating in a constrained frequency range. It is shown that with a 12.2% change in frequency as per SAE J2954 it is possible to compensate for a 90% variation of coupling coefficient. The analytical calculations are further validated by simulation in the PSIM software.