Rotating electric machine control device and electric power steering device using the same

A rotating electric machine control device for controlling a rotating electric machine having at least one winding set, which includes a plurality of windings for a plurality of phases respectively, the rotating electric machine control device comprising:

• at least one inverter having an upper arm element connected to a high-potential side and a lower arm element connected to a low-potential side of the upper arm element, and converting an electric power of the rotating electric machine;
• a terminal voltage detection device detecting a terminal voltage of each phase of a respective winding;
• a resistor connecting each phase of a respective winding and a positive side of a power supply;
• and
• a control device having a signal generation device that generates a control signal for controlling an on and off operation of the upper arm element and the lower arm element, and a failure detection device that detects a failure based on a sum of the terminal voltage in all of the phases when all of the control signals relating to the upper arm element and the lower arm element represents an off command, and a rotation speed of the rotating electric machine is lower than a predetermined rotation speed threshold.