Power conversion device with inverter circuit

A power conversion device comprising:

• an inverter circuit unit that includes an upper arm switching circuit and a lower arm switching circuit each having a plurality of switching elements;
• an upper arm gate circuit configured to output a gate signal to the upper arm switching circuit;
• a lower arm gate circuit configured to output a gate signal to the lower arm switching circuit;
• a gate drive power supply circuit configured to supply power to the upper arm gate circuit and the lower arm gate circuit;
• and
• a backup power supply circuit configured to supply the power to at least one of the upper arm gate circuit or the lower arm gate circuit instead of the gate drive power supply circuit,
• wherein
• the gate drive power supply circuit is configured to supply the power within a predetermined normal voltage range,
• the backup power supply circuit is configured to supply the power to at least one of the upper arm gate circuit or the lower arm gate circuit when a voltage of the power applied to at least one of the upper arm gate circuit or the lower arm gate circuit from the gate drive power supply circuit falls below the normal voltage range, and
• at least one of the upper arm gate circuit or the lower arm gate circuit is configured to drive each of the upper arm switching circuit and the lower arm switching circuit by causing one switching circuit of the upper arm switching circuit or the lower arm switching circuit to be in a short-circuited state in which all the switching elements are turned on and causing the other switching circuit to be in an opened state in which all the switching elements are turned off when the power is supplied from the backup power supply circuit,
• wherein the inverter circuit unit includes a temperature detection circuit configured to detect a temperature of each switching element of the upper arm switching circuit and the lower arm switching circuit, and an active discharge circuit configured to discharge electric charges accumulated in the inverter circuit unit, and
• the backup power supply circuit is configured to supply the power to at least one of the temperature detection circuit or the active discharge circuit when the voltage of the power applied to at least one of the upper arm gate circuit or the lower arm gate circuit from the gate drive power supply circuit falls below the normal voltage range.

A power conversion device comprising:

• an inverter circuit unit that includes an upper arm switching circuit and a lower arm switching circuit each having a plurality of switching elements;
• an upper arm gate circuit configured to output a gate signal to the upper arm switching circuit;
• a lower arm gate circuit configured to output a gate signal to the lower arm switching circuit;
• a gate drive power supply circuit configured to supply power to the upper arm gate circuit and the lower arm gate circuit;
• and
• a backup power supply circuit configured to supply the power to at least one of the upper arm gate circuit or the lower arm gate circuit instead of the gate drive power supply circuit,
• wherein
• the gate drive power supply circuit is configured to supply the power within a predetermined normal voltage range,
• the backup power supply circuit is configured to supply the power to at least one of the upper arm gate circuit or the lower arm gate circuit when a voltage of the power applied to at least one of the upper arm gate circuit or the lower arm gate circuit from the gate drive power supply circuit falls below the normal voltage range, and
• at least one of the upper arm gate circuit or the lower arm gate circuit is configured to drive each of the upper arm switching circuit and the lower arm switching circuit by causing one switching circuit of the upper arm switching circuit or the lower arm switching circuit to be in a short-circuited state in which all the switching elements are turned on and causing the other switching circuit to be in an opened state in which all the switching elements are turned off when the power is supplied from the backup power supply circuit,
• the power conversion device further comprising:
• a second inverter circuit unit that includes a second upper arm switching circuit and a second lower arm switching circuit each having a plurality of switching elements;
• a second upper arm gate circuit configured to output a gate signal to the second upper arm switching circuit;
• and
• a second lower arm gate circuit configured to output a gate signal to the second lower arm switching circuit,
• wherein
• the inverter circuit unit and the second inverter circuit unit are connected to a common motor, and
• the backup power supply circuit does not supply the power to any of the second upper arm gate circuit and the second lower arm gate circuit.