For high-power single-transmitter single-receiver wireless power transfer (STSRWPT) systems, the coils suffer from high voltage and current stresses. With increased power requirements, the coils become bottlenecks for power flow. To increase the power level, multiple-transmitter multiple-receiver wireless power transfer (MTMRWPT) systems with parallel circuits are developed that reduce the voltage and current stresses on the coils and improve power-handling capability. Firstly, an improved current distribution (ICD) control strategy is developed to simultaneously achieve high transfer efficiency, balanced current distribution and constant output voltage. Secondly, it is further shown that the ICD control strategy has the advantage that the currents at the transmitter coils are balanced and it reduces the control complexity simultaneously. Thirdly, an asynchronous particle swarm optimization (APSO) algorithm is applied to the ICD control strategy to verify the feasibility of the proposed control strategy. Lastly, a two-transmitter two-receiver wireless power transfer (WPT) system based on the ICD control strategy is proved to obtain an efficiency of more than 89.1% and provides the target output voltage 20 V with balanced current distribution.
Receiver power allocation and transmitter power control analysis for multiple-receiver wireless power transfer systems
