A Comparative Study of S-S and LCC-S Compensation Topology of Inductive Power Transfer Systems for EV Chargers

In inductive power transfer (IPT) systems, the structures and parameters of the resonance compensation topology are the main factors which determine the system characteristics. As the representative of conventional classical compensation topology and high-order composite compensation topology, series-series (S-S) and inductance-double capacitances-series (LCC-S) have been widely studied and applied to wireless charging for electric vehicles (EVs). In this paper, the properties of the two resonance topologies are compared comprehensively under the same conditions, the comparisons include influences of zero phase angle (ZPA) frequency and load variation on transmission performance, the characteristics of system voltage conversion ratio and input impedance angle under the condition of ZPA frequency and load variation. To complement the comparison and analysis, a 2kW level comparative experiments were carried out, it can be concluded that LCC-S is suitable for low power applications and S-S is suitable for high power applications. S-S has higher load sensitivity to the output characteristics than LCC-S.