Abstract: A current estimation section of a motor control apparatus carries out the following processing. When an AC motor is controlled under a current feedback control scheme (sine wave control mode or overmodulation control mode), a ?-axis current i? is calculated based on a current detection value iw_sns in a sensor phase and a current command value iv* in one other phase. When the AC motor is controlled under a torque feedback control scheme (rectangular wave control mode), the ?-axis current i? is calculated based on a differential value ?i? of an ?-axis current. Then a sensor phase reference current phase ?x is calculated to estimate a U-phase current. Thus it is possible to use the current feedback control scheme and the torque feedback control scheme together.

Abstract: A reference current phase sensing part of a sensor phase (W) calculates an ?-axis current i? and a ?-axis current i? in a fixed coordinate system formed with respect to a sensor phase as a base. The ?-axis current i? is calculated based on a sensed current iw.sns of the sensor phase and a ?-axis current i? is calculated based on command currents iu* and iv* of the other two phases (U, V) determined from a d-axis command current id* and a q-axis command current iq*. Then a current phase x?=tan?1(i?/i?) is calculated. A basic wave estimating part calculates an estimated current iu.est of the other phase by calculating an estimation coefficient corresponding to the reference current phase x? of the sensor phase and multiplying the sensed current iw.sns of the sensor phase by the estimation coefficient.

Abstract: A controller for a three-phase AC motor includes a current sensor and a current estimation section. The current sensor detects current flowing through one phase of the motor. The one phase is defined as a sensor phase. The current estimation section calculates a current phase relative to an axis of the sensor phase based on ?-axis current and ?-axis current in a stationary coordinate system defined by a ?-axis parallel to the sensor phase axis and a ?-phase perpendicular to the sensor phase axis. The current estimation section estimates current flowing through another phase of the motor based on the current phase and the detected current. The current estimation section calculates the ?-axis current based on the detected current. The current estimation section calculates the ?-axis current based on the detected current and a command value for the current flowing through the other phase of the motor.

Abstract: In a system for driving a three-phase rotating electrical machine of drive sources for applying separate drive forces to a rotary shaft, a phase of the rotating electrical machine, a current of which is detected by a current sensor and capable of being used for control of the rotating electrical machine, is defined as an effective sensor-phase of the rotating electrical machine. When the number of the effective sensor-phases is one, the rotating electrical machine is driven in a one-phase control mode based on the current of the effective sensor-phase under a condition where a rotation speed of the rotating electrical machine is greater than a predetermined positive threshold, and driven by the drive forces of the other drive sources under a condition where the rotation speed is not greater than the threshold.

Abstract: A control device for controlling a three phase AC motor with an inverter includes: a sensor phase current acquisition device for a sensor phase current sensed value; a rotation angle acquisition device for a rotation angle sensed value; a number-of-revolutions operation device for the revolution number; a current estimation device for a current estimated value; a first voltage command value operation device for a first voltage command value; a voltage command reference value operation device for a voltage command reference value; a second voltage command value operation device for a second voltage command value; a control mode switching device for switching to a first control mode when the revolution number is more than a threshold, and switching to a second control mode when the revolution number is not more than the threshold; and a torque abnormality monitoring device for monitoring an output torque during the second control mode.

Abstract: A control device for controlling a three phase AC motor with an inverter includes: a current acquisition device for a current of the motor; a rotation angle acquisition device for a rotation angle of the motor; a current estimation device for a current estimated value; a first voltage command value operation device for a first voltage command value; a voltage command reference value operation device for a voltage command reference value; a second voltage command value operation device for a second voltage command value; a control mode switching device for first and second control modes generating a drive signal of the inverter based on the first and second voltage command value, respectively; and a number-of-revolutions operation device. When the revolution number is more than a threshold, the first control mode is selected. When the revolution number is not more than the threshold, the second control mode is selected.

Abstract: An apparatus for controlling an AC motor driven by an inverter includes a two-phase calculator for calculating a two-phase control current value based on a first-phase current, a second-phase current, and a rotation angle of the motor, a one-phase calculator for calculating a one-phase control current value based on the first-phase current and the rotation angle, a determinator for determining whether a sudden change occurs based on a fluctuation in a rotation speed of the motor, a switch for selecting the one-phase control current value as a fixed value when no sudden change occurs and selecting the two-phase control current value as the fixed value when the sudden change occurs, and a voltage command value calculator for calculating a voltage command value related to a voltage applied to the inverter based on the current fixed value and a drive command value related to driving of the AC motor.

Abstract: A control device of a three phase AC motor includes: an inverter for driving the motor; a current sensor for sensing current flowing in a sensor phase of the motor; and a controller for switching multiple switching elements in the inverter to control the current of the motor. An electric angle is defined as ?e based on one phase. A phase is defined as ? based on a dq axis. A phase angle of a current command vector is defined as (?e+?+C). When the motor is stopped, the controller determines whether the current command vector is orthogonal to an axis of the sensor phase. When the current command vector is orthogonal to the axis of the sensor phase, the controller operates the phase or the electric angle to set the current command vector not to be orthogonal to the axis of the sensor phase.

Abstract: A motor control circuit calculates, based on a sensed current of a sensor phase sensed by a current sensor, an estimated current of the other phase and calculates a d-axis and a q-axis estimated currents based on the sensed current of the sensor phase and the estimated current of the other phase. The motor control circuit further calculates a d-axis and a q-axis command voltages based on the estimated currents thereby to control power supply to the AC motor. When the sensed current of the sensor phase is 0 [A], the command voltages are fixed and the estimated current is interpolated. Thus, variations of the command voltages caused by an error in the estimated current are reduced and a rapid change in the estimated current is reduced.

Abstract: A control device for controlling an AC motor with an inverter includes: a current acquisition device of a sensor phase current sensed value of the motor in a sensor phase current sensing cycle; a rotation angle acquisition device of a rotation angle sensed value of the motor; a current command value operation device for updating a current command value in a command update cycle; a current estimation device; a voltage command value operation device; a drive signal generation device; and a sudden change prevention device for preventing the voltage command value from a sudden change according to a sudden change in the current estimated value. The sudden change of the current estimated value is caused by a sudden change in the current command value.

Abstract: A motor control circuit calculates an ?-axis current i? and a ?-axis current i? in a fixed coordinate system based on a W-phase (sensor phase) of an AC motor. The control circuit calculates the ?-axis current i? from a current iw.sns sensed in the W-phase, and the ?-axis current i? from a differentiated value ?i? determined from the variation quantity of the ?-axis current based on that the ?-axis current i? and the ?-axis current i? are in a relation of a sine wave and a cosine wave. Subsequently, the control circuit calculates a current phase x?=tan?1(i?/i?) relative to the W-phase. Subsequently, the control circuit calculates an estimation factor according to the current phase x? and determines an estimated current iu.est in the U-phase of the AC motor by multiplying the sensed current iw.sns by the calculated estimation factor.

Abstract: According to a control apparatus for an AC motor, a switching section selects a two-phase control current value as a current fixing value, when a first current detection value of a first phase of the AC motor and a second current detection value of a second phase of the AC motor are normal. The switching section selects an one-phase control current value, which is calculated based on a normal phase current detection value, which is a value of the normal phase and is one of the first and the second current detection values, as the current fixing value, when it is determined that the current supplied to the AC motor has been stabilized after an abnormality is detected in part of the first and second detection values.

Abstract: According to a control apparatus for an AC motor, a switching section selects a two-phase control current value as a current fixing value, when a first current detection value of a first phase of the AC motor and a second current detection value of a second phase of the AC motor are normal. The switching section selects an one-phase control current value, which is calculated based on a normal phase current detection value, which is a value of a normal phase and is one of the first and second current detection values, as the current fixing value, when an abnormality is detected in part of the first and second current detection values, and a predetermined period has elapsed from the detection of the abnormality.

Abstract: A control apparatus controls an AC motor by detecting current passing through one phase. The apparatus includes an upper controller which includes a torque command calculation section, and a torque monitoring section monitoring torque to determine whether the torque is within a range, and a lower controller which controls current supply to an inverter based on a torque command value to control the motor, and which acquires information on a current-supply state and a rotation state of the motor and transmits information on a control state to the upper controller. At least one of the controllers estimates a current estimate value of an estimated phase or a d-q axis current estimate value based on a current detection value of the one phase and an electrical angle, and calculates information for monitoring torque based on the current estimate value. The torque monitoring section monitors the torque based on the information.

Abstract: In a motor control apparatus for controlling an AC motor with an inverter, a current estimation value is calculated based on a current detection value of one phase of the motor and a rotation angle of the motor. A difference between a current command value related to driving of the AC motor and the current estimation value is calculated. A first voltage command value used to generate a drive signal related to driving of the inverter is calculated based on the difference. A sign of the difference is reversed at a reverse interval when the rotation speed is not greater than a determination threshold.

Abstract: A control device of a three-phase AC motor includes: an inverter that drives the AC motor; a current sensor that senses a current flowing in a sensor phase of the AC motor as a sensor phase current; and a controller that switches on and off a switching element of the inverter to control a current flowing through the AC motor. The controller includes: a current estimation device that estimates d-axis and q-axis current estimated values based on the sensor phase current and an electric angle of the AC motor; and a zero-crossing interpolation device that interpolates a command value relating to a voltage of the AC motor when the sensor phase current is in a zero cross range, which includes a zero point. When the sensor phase current is in the zero cross range, the zero-crossing interpolation device interpolates the command value with a continuous variable value.

Abstract: A control device of a three-phase AC motor includes: an inverter for driving the motor; a current sensor for sensing a sensor phase current of the motor; and a controller for controlling the motor. The controller includes: a current estimation device for estimating d-axis and q-axis current estimated values based on the sensor phase current and an electric angle of the motor; and a zero-crossing interpolation device for interpolating the d-axis and q-axis current estimated values by fixing the d-axis and q-axis current estimated values when the sensor phase current is in a zero cross range, which includes a zero point, so that the sensor phase current crosses the zero point, and for outputting interpolated d-axis and q-axis current estimated values as fixed d-axis and q-axis values, which are used for a feedback control relating to current flowing through the motor.

Abstract: A control device of a three-phase AC motor includes: an inverter; a current sensor for a sensor phase current; and a controller switching a switching element of each phase of the inverter and having a current estimation device, which calculates a sensor-phase-standard current phase according to ? and ? axis currents and a current estimated value of another phase. The current estimation device calculates the ? axis current at every switching and intermediate timings, calculates a first differential value of the ? axis current at every switch timing, calculates the ? axis current according to the first differential value, calculates a second differential value of the ? axis current at every intermediate timing, and calculates the ? axis current according to the second differential value. The intermediate timing is set to have an unequal interval between two adjacent switch timings.

Abstract: A motor control circuit calculates an ?-axis current i? and a ?-axis current i? in a fixed coordinate system based on a W-phase (sensor phase) of an AC motor. The control circuit calculates, at each switching time point and each intermediate time point, the ?-axis current i? from a current iw.sns sensed in the W-phase, and the ?-axis current i? from a differentiated value ?i? determined from the variation quantity of the ?-axis current between every two successive switching time points or intermediate time points. Subsequently, the control circuit calculates a current phase x?=tan?1(i?/i?) relative to the W-phase. Subsequently, the control circuit calculates an estimation factor according to the current phase x? and determines an estimated current iu.est in the U-phase of the AC motor by multiplying the sensed current iw.sns by the calculated estimation factor.

Abstract: A control device of a three phase AC motor includes: an inverter for driving the motor; a current sensor for sensing current flowing in a sensor phase of the motor; and a controller for switching multiple switching elements in the inverter to control the current of the motor. An electric angle is defined as ?e based on one phase. A phase is defined as ? based on a dq axis. A phase angle of a current command vector is defined as (?e+?+C). When the motor is stopped, the controller determines whether the current command vector is orthogonal to an axis of the sensor phase. When the current command vector is orthogonal to the axis of the sensor phase, the controller operates the phase or the electric angle to set the current command vector not to be orthogonal to the axis of the sensor phase.