基于次级改进型有源整流的无线电能传输系统

Wireless Power Transmission System Based on Improved Active Rectifier at Receiving Terminal

在无线电能传输(WPT)系统中,为了降低系统接收端复杂度且控制输出,出现了次级有源整流的整流模式,针对现有控制方法存在非阻性阻抗下效率低、控制策略设计复杂等问题,在此提出了次级改进型有源整流控制策略,降低了开关管的导通损耗及开关损耗,实现了效率优化,无需额外并联二极管也可保证效率,降低了系统成本,且控制方法简便,可实现恒流恒压输出控制,适用于电池充电的应用场景。首先介绍了系统结构与工作模态,其次详细分析了次级改进型有源整流提升效率及控制输出的原理,同时给出了具体的控制框图。最后设计了系统在恒流模式下3A输出和恒压模式下29.4V输出的验证装置,变负载下可实现恒定输出控制及模式切换,验证了系统的可行性和稳定性。

In wireless power transmission(WPT)system,in order to reduce the complexity of the receiving end of the system and control the output,a rectification mode of active rectification on the secondary side appears.Aiming at the problems of low efficiency under non-resistive impedance and complicated control strategy design of the existing con-trol methods,an improved active rectification control strategy on the secondary side is proposed,which reduces the conduction loss and switching loss of the switching tube,realizes the efficiency optimization,ensures the efficiency without additional parallel diodes,reduces the system cost,and the control method is simple and realizable.Firstly,the system structure and working mode are introduced.Secondly,the principle of improving efficiency and controlling out-put of the secondary-side improved active rectifier is analyzed in detail,and the specific control block diagram is giv-en.Finally,the verification devices of 3 A output in constant current mode and 29.4 V output in constant voltage mode are designed,which can realize constant output control and mode switching under variable load,and verify the feasibility and stability of the system.