LAUSR

In a wireless power transfer (WPT) system, the efficiency decreases as the distance (DIS) or misalignment (MIS) between transmitter (Tx) coil and receiver (Rx) coil increases. As a result, the received load power is varying under different DIS/MIS conditions. Increasing the system efficiency and maintaining constant/stable output voltage/power are the major control targets in WPT system. This paper presents the evaluation of input power splitting (IPS) WPT system with multiple Tx coils (MTxWPT) in order to extend the area of output voltage/power stabilisation under varying DIS and MIS conditions, while improving the system efficiency at the same time. The control algorithm is realised by adaptively optimising the IPS multipliers α 1 through αn to unequally split the input power (P 1 through Pn ) between multiple Tx coils. The maximum system efficiency point can be achieved with the optimum selection of IPS multipliers (α 1 through αn ). A DC–DC converter at Rx side is utilised to maintain the output voltage/power at a constant/stable value. Detailed sets of the model analysis and experimental prototype results are provided and discussed through the paper to evaluate the performance of the presented IPS MTxWPT system.