Power conversion device

A power conversion device, comprising:

• a plurality of power conversion units each comprising power converting circuitry that converts electric power supplied from a power source into electric power for supply to a load and supplies the converted electric power to the load, a contactor that electrically connects the power converting circuitry to the power source or electrically disconnects the power converting circuitry from the power source, and unit controlling circuitry that controls switching elements included in the power converting circuitry, the plurality of power conversion units being configured to be connected in common to the power source;
• contactor controlling circuitry to close or open the contactor included in each of the plurality of power conversion units;
• and
• a sensor to measure a value of at least one of input current or output current of the power converting circuitry included in each of the plurality of power conversion units, and output the measured value of the at least one of the input current or the output current of the power converting circuitry, wherein
• the unit controlling circuitry of the plurality of power conversion units are connected to one another through a transmission line, and
• each of the unit controlling circuitry determines presence or absence of a failure of the power conversion unit based on the measured value of the at least one of the input current or the output current of the power converting circuitry that is a control target and whether the contactor associated with the power converting circuitry that is the control target is in a closed state or an open state, and sends a determination result to another unit controlling circuitry of the unit controlling circuitry.