Cost-effective inductive power transfer charging system for electric bicycles with variable charging current using primary-side detuned series-series topology

摘要

Due to the convenience and long travelling distance, electric bicycles (EBs) are becoming more and more popular. Charging EBs with inductive power transfer (IPT) technology can free people from wearisome plugging actions and avoid electric shock hazards. However, the cost, including component cost and control cost, is a big challenge for the extensive promotion of the IPT charging systems (IPTCSs) for EBs. This article proposes an IPTCS using primary-side detuned series-series (SS) compensation topology, cancelling control scheme and reducing the component cost. With the proposed parametric design method, the IPTCS can operate with variable charging current according to the variable equivalent resistance of a battery. Besides, the inductive input impedance is guaranteed to achieve soft switching for the high-frequency inverter. An experimental setup is constructed to validate the proposed method. The performance shows that the charging current decreases from 1.8 to 0.1 A, and charging voltage increase from 42.23 to 54.01 V during the whole charging process, where the maximum efficiency of the IPTCS can reach up to 92.8%. The results demonstrate the proposed IPTCS is a cost-effective and potential solution for charging EBs.