Generalized PT-Symmetric Wireless Power Transfer Systems With Laterally Arranged Multirelays

The concept of parity-time (PT) symmetry, when applied in wireless power transfer (WPT) systems, helps to prevent a decrease in power delivery. In existing research on PT-symmetric WPT systems with laterally arranged multirelays, employed for expanding the lateral transfer region, only a special case has been considered for the coupling coefficient required to achieve PT symmetry. This strict special case condition increases the complexity and difficulty of implementing the system in reality. In this letter, a general condition of coupling coefficient for the PT-symmetric system with laterally arranged multirelays is analytically derived, by reducing a high-order Hamiltonian to an equivalent second-order one. The theoretical derivation is experimentally verified. An experimental system example with two relays demonstrates about a 100% increase in lateral transfer distance with stable power transfer, compared to the traditional system without relays. Our work paves the way for implementation of simpler high-order PT-symmetric systems.