直列および並列共振コンデンサを用いた非接触給電システム

Abstract

A new contactless power transfer system using series and parallel resonant capacitors is described. If the primary series resonant capacitor and the secondary parallel resonant capacitor are chosen appropriately, the equivalent circuit of the transformer with these capacitors becomes very simple at the resonant frequency. Ignoring the winding resistance and the core loss, the equivalent circuit is the same as an ideal transformer. Therefore, the circuit analysis is easy, and if the input voltage is constant, the output voltage is also constant regardless the output current. Fig. 1 shows the configuration of our contactless power transfer system. The ferrite-core transformer with 10~20 mm gap is drived by 10 kHz rectangular waveform inverter. As the winding resistance and the ferrite-core loss are very small, the simplified equivalent circuit of Fig. 2 can be used. The parallel capacitor Cp at the secondary winding and the series capacitor Cs at the primary winding are determined as following values. 1 ω0CP = xP = x0 + x2 · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · (1)