Patent ID: 7755573

Claim:
A charging/discharging apparatus for charging a capacitance to be charged/discharged by applying a voltage, the apparatus comprising: a recovery capacitor for recovering electric energy, having one terminal connected to a first power supply through first switch means and another terminal connected to a second power supply through second switch means; first path forming means, having one terminal connected to a connection point between the second power supply and the other terminal of the recovery capacitor and another terminal connected to the capacitance to be charged/discharged, for charging the capacitance to be charged/discharged through a resonant inductor when the first switch means is turned on; second path forming means, having one terminal connected to a connection point between the first power supply and the one terminal of the recovery capacitor and another terminal connected to the capacitance to be charged/discharged, for discharging the capacitance to be charged/discharged through the resonant inductor when the second switch means is turned on to recover electric energy in the recovery capacitor; a third capacitor for recovering electric energy having one terminal connected to a third power supply through third switch means and another terminal connected to the first power supply through fourth switch means; third path forming means, having one terminal connected to a connection point between the third power supply and the one terminal of the third capacitor and another terminal connected to the capacitance to be charged/discharged, for charging the capacitance to be charged/discharged through the resonant inductor when the third switch means is turned on; fourth path forming means, having the one terminal connected to a connection point between the fourth power supply and the other terminal of the third capacitor and the other terminal connected to the capacitance to be charged/discharged, for discharging the capacitance to be charged/discharged through the resonant inductor when the fourth switch means is turned on to recover electric energy to the third capacitor; and control means for controlling the first, second, third, and fourth switch means and the first, second, third, and fourth path forming means.