The Bifurcated Detection using the Sensing Coil for Parallel-Parallel Compensation in IPT System

The bifurcation phenomenon is the usually found in inductive power transfer system (IPT). The coupling and load on secondary side that induce the bifurcation cannot could not be directly measured. This paper presents the bifurcated detection by using the sensing coil. The sensing coil is placed on the secondary side. The phase of the sensing coil voltage is compared with the phase of secondary voltage to indicate the bifurcation. The frequency responses show that the phase difference between sensing coil voltage and secondary voltage is decreased when increased the secondary quality factor. The experimental results revealed that the bifurcation was detected from the secondary side in both perfect alignment and misalignment condition. By using the proposed circuit, the bifurcation detection from the secondary side is possible.