Coupling Coefficient Estimation in Inductive Power Transfer Systems Through Damped Frequency

This letter proposes a novel approach for estimating coupling coefficients in inductive power transfer systems based on damped frequencies. In systems incorporating a voltage load, disturbances can lead to current/power oscillations at a damped frequency due to poorly damping characteristics. By analyzing the damped frequency of the oscillating components of dc-side currents, the coupling coefficient can be accurately determined without the need for wireless communication, additional hardware, and complex calculations. Experimental results demonstrate the effectiveness of the proposed method, which can estimate coupling coefficients within 0.5 ms based on dc-side currents.