Wireless fleet charging system for electric bicycles

This paper proposes a double coupled inductive system for multi-pickup systems which is intended for wireless charging of a fleet of electric bicycles. An intermediary coupler is introduced between the primary and pickup and operates as a switch, with the intention of turning on when the bicycle is present and turning off when the bicycle is absent to prevent magnetic fields from radiating into the environment. The switching method for the proposed intermediary coupler configuration provides quick turn on and off without significant transient spikes. A sensitivity analysis was undertaken to analyze reflected impedance at the primary due to variations in the tuning components. A practical system has been built which is capable of producing up to 400W at its output. The proposed intermediary coupler and pickup has achieved an efficiency of 86% at 400W output. The overall system efficiency including the intermediary coupler and pickup was 76%. With more branches of intermediary couplers and pickup drawing power from the primary power, the standings losses in the system are shared and the system efficiency would be higher.