Motor controller, electric power steering device using the motor controller, and vehicle using the motor controller

A motor controller that drives and controls a multiphase electric motor,

• the motor controller comprising:
• a plurality of motor drive circuits configured to supply multiphase motor drive current to multiphase motor windings of the multiphase electric motor;
• a control operation device configured to drive and control the plurality of motor drive circuits;
• a plurality of motor current cutoff units respectively arranged between the plurality of motor drive circuits and the multiphase motor windings;
• and
• an abnormality detection unit configured to detect an abnormality of at least one of the plurality of motor drive circuits,
• wherein when the abnormality detection unit does not detect the abnormality, the control operation device controls the plurality of motor drive circuits to supply the multiphase motor drive current to the multiphase motor windings,
• wherein when the abnormality detection unit detects the abnormality, the control operation device cuts off any of the plurality of motor current cutoff units connected to any of the plurality of motor drive circuits where the abnormality occurs,
• wherein each of the plurality of motor drive circuits includes a multiphase inverter circuit having at least one upper arm and at least one lower arm having a number of arms corresponding to the number of phases of the multiphase electric motor, and configured to supply the multiphase motor drive current to the multiphase electric motor,
• wherein the abnormality detection unit detects at least one of an open failure or a short-circuit failure of the at least one upper arm and the at least one lower arm included in the plurality of motor drive circuits,
• wherein the abnormality detection unit comprises:
• an upper current detection resistance arranged on a positive-side power supply line to which the at least one upper arm are connected;
• a lower current detection resistance arranged on a negative-side power supply line to which the at least one lower arm are connected;
• and
• a plurality of current detection units configured to individually detect a voltage between terminals of the upper current detection resistance and the lower current detection resistance, and
• wherein the motor controller further comprises:
• a plurality of overcurrent determination units configured to individually determine whether or not each of the current values detected by the plurality of current detection units is in an overcurrent state where the current value exceeds an overcurrent threshold;
• and
• a plurality of current bypass circuits connected between a power supply system that individually supplies power to the plurality of motor drive circuits and the ground,
• wherein each of the plurality of current bypass circuits comprises a switch unit, and
• wherein when a determination result of any one of the plurality of overcurrent determination units is the overcurrent state, the switch unit is controlled to be in the on state.