Abstract: A power conversion device in an embodiment includes a first power converter; a plurality of direct current-direct current (DCDC) converter devices; and a second power converter. The first power converter includes a plurality of first positive-side arms; a plurality of first negative-side arms; a first positive-side star connection line configured to connect the plurality of first positive-side arms in a star shape; a first negative-side star connection line configured to connect the plurality of first negative-side arms in a star shape; and a first terminal configured to connect the first positive-side star connection line and the first negative-side star connection line to each phase of a power supply side alternating current (AC) system and the plurality of first positive-side arms and the plurality of first negative-side arms mutually convert a first AC power and a first DC power of the power supply side AC system.

Abstract: A power conversion device in an embodiment includes a first power converter; a plurality of direct current-direct current (DCDC) converter devices; and a second power converter. The first power converter includes a plurality of first positive-side arms; a plurality of first negative-side arms; a first positive-side star connection line configured to connect the plurality of first positive-side arms in a star shape; a first negative-side star connection line configured to connect the plurality of first negative-side arms in a star shape; and a first terminal configured to connect the first positive-side star connection line and the first negative-side star connection line to each phase of a power supply side alternating current (AC) system and the plurality of first positive-side arms and the plurality of first negative-side arms mutually convert a first AC power and a first DC power of the power supply side AC system.

Abstract: In a power converter, a first single-phase AC conversion unit, which is connected to a first line of a first phase and a second line of a second phase of a first three-phase AC, a second single-phase AC conversion unit, which is connected to the second line of the second phase and a third line of a third phase of the first three-phase AC, and a third single-phase AC conversion unit, which is connected to the third line of the third phase and the first line of the first phase of the first three-phase AC, form a delta-connected load for an AC power supply system. At least the first single-phase AC conversion unit, the second single-phase AC conversion unit, and the third single-phase AC conversion unit form a first set in which respective output terminals are connected in series to one another, and the first set, and a second set and a third set, which are different from the first set, form each phase of a star connected power supply.

Abstract: In a power converter, a first single-phase AC conversion unit, which is connected to a first line of a first phase and a second line of a second phase of a first three-phase AC, a second single-phase AC conversion unit, which is connected to the second line of the second phase and a third line of a third phase of the first three-phase AC, and a third single-phase AC conversion unit, which is connected to the third line of the third phase and the first line of the first phase of the first three-phase AC, form a delta-connected load for an AC power supply system. At least the first single-phase AC conversion unit, the second single-phase AC conversion unit, and the third single-phase AC conversion unit form a first set in which respective output terminals are connected in series to one another, and the first set, and a second set and a third set, which are different from the first set, form each phase of a star connected power supply.

Abstract: An inverter test apparatus includes a DC power supply, a second inverter which is connected to a DC side of the first inverter, an inductor which is connected between an AC side of the first inverter and an AC side of the second inverter, a first controller which controls an AC voltage of the first inverter to be at a constant amplitude and a constant frequency, a current detector which detects a current that flows through the inductor, a phase command value computation module which computes a phase command value of the second inverter so as to control the current detected by the current detector, and a second controller which controls a phase of the second inverter, based on the phase command value computed.

Abstract: An inverter test apparatus includes a DC power supply, a second inverter which is connected to a DC side of the first inverter, an inductor which is connected between an AC side of the first inverter and an AC side of the second inverter, a first controller which controls an AC voltage of the first inverter to be at a constant amplitude and a constant frequency, a current detector which detects a current that flows through the inductor, a phase command value computation module which computes a phase command value of the second inverter so as to control the current detected by the current detector, and a second controller which controls a phase of the second inverter, based on the phase command value computed.