Patent ID: 8314513

Claim:
A power transmission control device that controls a power transmission device in a contactless power transmission system that transmits power from the power transmission device to a power reception device through electromagnetically coupling a primary coil and a secondary coil, the power transmission control device comprising: a power transmission driver control section that controls drive timings of a plurality of switching elements of a power transmission driver that drives the primary coil, the power transmission driver including a first driver and a second driver, the power transmission driver controlling section variably controls the power to be transmitted from the power transmission device to the power reception device the second driver driving the primary coil such that a drive current flowing through the primary coil is opposite to a direction of a drive current flowing through the primary coil when driven by the first driver; each of the first driver and the second driver includes a first switching element to which a high potential power supply is supplied and a second switching element to which a low potential power supply is supplied; and the power transmission driver control section varies a phase difference between a first drive signal for driving the first switching element and a second drive signal for driving the second switching element.