Saitama University

Toyota Jidosha Kabushiki Kaisha

National University Corporation Saitama University

Hiroyoshi Kaneko

Shigeru Abe

Shinji Ichikawa

Masayuki Komatsu

A power transmitting device includes power transmitting coils, which contactlessly transmit electric power to a power receiving coil, and a switching device. When the power receiving coil is a solenoid coil, the switching device connects the power transmitting coils in parallel with each other such that magnetic fluxes generated inside the power transmitting coils flowing in the same direction along a winding axis. When the power receiving coil is a circular coil, the switching device connects the power transmitting coils in series with each other such that magnetic fluxes generated inside the power transmitting coils flowing in opposite directions along the winding axis.

Power receiving device, power transmitting device and power transfer system

[Problems] To provide a non-contact power feeder that is high efficient and high power factor and has no load dependence. [Means for Solving Problems] A series capacitor Csis connected to a primary windingdriven by an AC power supplyand a parallel capacitor Cpis connected to a secondary winding. The capacitance Cp is set to Cp&#x2248;1/{2&#x3c0;f&#xd7;(x+x)} and the capacitance Cs converted to the primary side is set to Cs&#x2248;(x+x)/{2&#x3c0;f&#xd7;(x&#xd7;x+x&#xd7;x+x&#xd7;x)}, where fis the frequency of the power supply, xis a primary leakage reactance of the primary winding, xis a secondary leakage reactance of the secondary windingconverted to the primary side and xis an excitation reactance converted to the primary side. By setting Cp and Cs to the above values, the transformer of the non-contact power feeder is substantially equivalent to an ideal transformer. If it is driven by a voltage type converter, the output voltage (=load voltage) becomes substantially constant voltage regardless of the load. In case of a resistive load (ZL=R), the power factor of the power supply output always remains 1 even if the load may vary.

Growing community of inventors

Saitama, Japan

Hiroyoshi Kaneko