Unified Theory of Non-Resonant and Resonant Circuits in Inductive Power Transfer and Capacitive Power Transfer

This paper provides a general and systematic comparison of the transmission characteristics for circuits non-resonant, series resonant, and parallel resonant circuits of both Inductive Power Transfer (IPT) and Capacitive Power Transfer (CPT) systems. The transmission characteristics were CC/CV characteristic, efficiency, and output power when the power source is a voltage or current source. In terms of the compensation condition and CC/CV characteristic, S-S in IPT and P-P in CPT were superior because the compensation condition does not depend on the coupling coefficient and they had gyrator characteristic. For the efficiency, it was found that, for both IPT and CPT, it was suitable to use S or P on the receiver side for high efficiency. For the output power, in common with IPT and CPT, higher power can be obtained by choosing S on the transmitter side when a voltage source was used and P on the transmitter side when a current source was used. Therefore, it is clear that the circuits with superior compensation condition, CC/CV characteristic, optimal load, efficiency, and output power were S-S in IPT when a voltage source was used and P-P in CPT when a current source was used.