Abstract: 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.

Abstract: 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.

Abstract: [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 Cs1 is connected to a primary winding 1 driven by an AC power supply 3 and a parallel capacitor Cp2 is connected to a secondary winding 2. The capacitance Cp is set to Cp?1/{2?f0×(x0+x2)} and the capacitance Cs converted to the primary side is set to Cs?(x0+x2)/{2?f0×(x0×x1+x1×x2+x2×x0)}, where f0 is the frequency of the power supply, x1 is a primary leakage reactance of the primary winding 1, x2 is a secondary leakage reactance of the secondary winding 2 converted to the primary side and x0 is 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.

Abstract: [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 Cs1 is connected to a primary winding 1 driven by an AC power supply 3 and a parallel capacitor Cp2 is connected to a secondary winding 2. The capacitance Cp is set to Cp?1/{2?f0×(x0+x2)} and the capacitance Cs converted to the primary side is set to Cs?(x0+x2)/{2?f0×(x0×x1+x1×x2+x2×x0)}, where f0 is the frequency of the power supply, x1 is a primary leakage reactance of the primary winding 1, x2 is a secondary leakage reactance of the secondary winding 2 converted to the primary side and x0 is 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.