ELECTRIC POWER TRANSMITTING APPARATUS AND NONCONTACT ELECTRIC POWER TRANSMISSION SYSTEM

摘要

A system for transmitting an electric power from an electric power transmitting apparatus (10) to an electric power receiving apparatus (50) by use of the electromagnetic induction between a power receiving coil (60) and a power transmitting coil (40).  The electric power transmitting apparatus (10) comprises a power switching circuit (14), a first capacitor (20) and a power deriving circuit (30).  The power switching circuit (14), which includes a switching element (16) and an output point (P), switches the switching element (16) at a predetermined switching frequency (f), thereby causing the potential at the output point (P) to exhibit a predetermined variation, which is like a potential variation obtained by the half-wave rectification of a sinusoidal wave variation having a given amplitude.  The first capacitor (20) is connected between the output point (P) and a first fixed potential point (ground).  The power deriving circuit (30), which includes the power transmitting coil (40), causes an AC variation included in the foregoing predetermined variation to appear across the power transmitting coil (40).  The power deriving circuit (30) is connected between the output point (P) and a second fixed potential point (ground).