Abstract: A control apparatus for an electric vehicle is provided, which is capable of reducing the weight of the electric vehicle and preventing the inverter circuit from overheating. When the vehicle stops on an uphill due to stalling, the control unit 30 starts counting the time over which current is supplied through the same IGBT element. When the count value reaches a value corresponding to the time at which the IGBT 40 starts generating heat, the control unit 30 outputs a control signal to reduce the motor driving current to the IPM 20. The rotation sensor 60 detects the rotational position when the motor rotates in the reverse direction, while the reduction of the motor driving current reduces the driving power of the motor. Based on the detection of the rotational position, the control unit 30 performs switching of the phase of the IGBT 40, and when the normal current supply phase is connected, the motor driving current which drives the motor is increased.

Abstract: A control device for an alternating current motor includes: a target current generating unit which generates a current order value, based on a torque order, as a d-axis target current and a q-axis target current on dq coordinates; a current detection device which detects an alternating current supplied to each phase of a polyphase alternating current motor; a coordinate transforming unit which transforms the alternating current detected by the current detection device into a d-axis current and a q-axis current on the dq coordinates; and a vector control unit which carries out a current feedback control so that the d-axis current follows up the d-axis target current and the q-axis current follows up the q-axis target current.

Abstract: An AC motor controlling apparatus which can exactly control the torque of an AC motor throughout a motor rotating speed range from low to high.A control mode selecting circuit 13 actuates a switching circuit 19 for allowing an exciting circuit 12 to receive a PWM signal S11 from a current feedback circuit 11 when the rotating speed Nm of the motor 1 is in a higher range, and a PWM signal from an AND gate 14 when it is in a lower range. A power feedback circuit 10 performs a feedback control for matching the power supplied to an inverter circuit 6 to a target power. The current feedback circuit 11 performs a feedback control for matching the phase currents to a target currents.