POWER CONVERSION APPARATUS AND CONTROL APPARATUS FOR SAME

To provide a power conversion apparatus for reducing time taken for initial charging and discharging operations of the power conversion apparatus, and reducing the size of the initial charging device, and to further provide the control apparatus. A power conversion apparatus includes a unit converter that is formed through parallel connection of a capacitor and a switching circuit constituted by two sets of series-connected switching elements having reflux diodes connected in parallel, a power converter that forms an arm having circulating current suppression reactors connected in series, forms a leg by two sets of the arms connected in series, and connects a connection point of the two sets of the arms, serving as an AC terminal to a phase of a first AC power source to cause both ends of the leg to serve as DC terminals, and a charging and discharging device having one end connected to a second AC power source, and the other end connected to the phase of the first AC power source. The charging and discharging device includes a tapped transformer which makes a position switchable between a high-voltage tap position and a low-voltage tap position, and is connected to the power converter instead of the first AC power source when starting and stopping the power converter.