Non-contact power supply device

FIELD: electricity. SUBSTANCE: device is composed of the following components: a power transmission circuit containing a coil for power transmission; and a charging circuit containing a power reception coil. The power is transmitted in a non-contact way from the power transmission coil to the power reception coil. When a vehicle approaches to the power supply device, a test power supply is performed when insignificant values of energy are transmitted, and on the basis of the current flowing through the power transmission circuit the efficiency of power transmission from the power transmission coil to the power reception coil is estimated. Using the power transmission efficiency it is possible to establish, whether the power reception coil is in a chargeable range for the power transmission coil or not. EFFECT: improvement of charging efficiency. 6 cl, 6 dwg