Transmitter Pulsation Control for Dynamic Wireless Power Transfer Systems

Wireless power transfer (WPT) is a convenient, flexible, and safe alternative to its wired counterpart. Due to these benefits, WPT has seen rapid growth in recent years. Typical WPT systems are usually used for static applications, where the load operates within a predefined area. On the other hand, dynamic WPT (D-WPT) is usually used to power loads which dynamically change their positions, and one of the ways to achieve this is by increasing the overall charging area via multiple transmitters (Txs). Multiple Txs require communication and control, which increases the overall complexity of the system. This paper proposes a control algorithm which aims to maintain the overall efficiency of the D-WPT system by turning on and off the Tx when the mobile receiver (Rx) approaches and departs, respectively. Transient analysis of the D-WPT system is used to derive its control variables. In addition, energy and power loss of this proposed control algorithm are also investigated. The feasibility of the proposed control algorithm is demonstrated with 1-Tx and 3-Tx experimental setups. The experimental results validate the theoretical analysis model and the proposed control algorithm, and the standby (when not charging) input power forms 7.6% of the charging input power.