Inverter driver

An inverter driver comprising:

• driving circuits configured to transmit driving signals to a plurality of switching elements included in an inverter circuit, the inverter circuit being connected to a direct-current power supply and an alternating-current rotating electric machine and configured to convert multi-phase alternating-current power to direct-current power and convert direct-current power to multi-phase alternating-current power, wherein:
• the inverter circuit includes a plurality of arms each provided for an associated one of alternating-current phases, the arms each including a series circuit of an upper switching element and a lower switching element, and
• the driving circuits are each configured to relay a switching control signal so as to transmit the driving signal to an associated one of the switching elements, the switching control signal being output from an inverter controller that controls the inverter circuit, the driving circuits including an upper driving circuit to transmit the driving signal to the associated upper switching element, and a lower driving circuit to transmit the driving signal to the associated lower switching element;
• an overvoltage protector configured to output an overvoltage protection signal when a voltage of a direct-current side of the inverter circuit is equal to or higher than a preset overvoltage threshold value;
• a resetting circuit configured to set, in accordance with at least the overvoltage protection signal, a signal level of the driving signal to be output from each of the associated driving circuits at a signal level that turns off the associated switching element;
• and
• control signal changing circuits each connected between the inverter controller and the associated driving circuit, the control signal changing circuits each being configured to transmit, instead of the switching control signal, a control signal to the associated driving circuit in accordance with the overvoltage protection signal, the control signal having a logical level that turns on the associated switching element irrespective of a logical level of the switching control signal, wherein:
• one of the upper driving circuit and the lower driving circuit is a first driving circuit, and the other of the upper driving circuit and the lower driving circuit is a second driving circuit, and
• the resetting circuit is connected to each of the first driving circuits for all of the phases, and the control signal changing circuits are each connected between the inverter controller and an associated one of the second driving circuits for all of the phases.