Denso Corporation

Toyota Jidosha Kabushiki Kaisha

Hirofumi Kako

Takeshi Itoh

Ryuji Omata

Takashi Suzuki

Kenji Yamada

Makoto Nakamura

Kazuhito Hayashi

Kiyotaka Matsubara

Akiyoshi Morii

A control apparatus is provided for controlling drive of a rotating electric machine that has coils of two or more phases. The control apparatus includes a first inverter to be connected with first ends of the coils, a second inverter to be connected with second ends of the coils, and a controller. The first inverter has a plurality of first switching elements each corresponding to one of the coils. The second inverter has a plurality of second switching elements each corresponding to one of the coils. The controller includes a first operation circuit configured to generate a first control signal for control of the first inverter and a second operation circuit configured to generate a second control signal for control of the second inverter. Moreover, the control apparatus is configured so that switching timings are synchronized, based on synchronization information, between the first and second inverters.

Control apparatus for rotating electric machine

A control apparatus includes an inverter for driving a three-phase AC motor when connected to a DC power source, a smoothing capacitor interposed between the DC power source and an input side of the inverter and connected in parallel to the DC power source, a current sensor for detecting a current of one phase of the motor, and a controller for controlling the motor through the inverter. The controller performs a discharge process to discharge the capacitor, when the DC power source is disconnected from the capacitor. The controller calculates a d-axis voltage command reference value based on d-axis and q-axis current command values. The controller sets a q-axis voltage command reference value to zero. The controller generates d-axis and q-axis voltage command values by correcting at least the d-axis voltage command reference value and outputs the d-axis and q-axis voltage command values to the inverter.

Control apparatus for AC motor

A control apparatus for an AC motor includes a current sensor and an estimation section. The current sensor detects current flowing through one phase of the motor. The estimation section repeats an estimation process. In the estimation process, d-axis and q-axis current estimation values are calculated based on the presently detected current of the one phase and a previous current estimation value of another phase of the motor, and a present current estimation value of each phase is calculated based on smoothed values of the d-axis and q-axis current estimation values. The estimation section performs the estimation process based on a phase lag element. The phase lag element is a difference between the presently detected current and a previous current estimation value of the one phase or the previously detected current.

AC motor control apparatus

A control device of a three phase AC motor includes: an inverter for driving the motor; a current sensor for sensing current 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. The controller includes: a revolution number calculation device for calculating the revolution number of the motor; a three-phase voltage command operation device for operating three phase voltage commands to be applied to the motor based on a current command and an electric angle; and a current concentration determination device for determining whether a current concentration is caused based on the three phase voltage commands when the revolution number is not more than a predetermined revolution number. In the current concentration, current not less than a predetermined threshold value flows continuously for a predetermined period in one or more phases of the inverter.

Control device of AC motor

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 &#x3b2;-axis current i&#x3b2; 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 &#x3b2;-axis current i&#x3b2; is calculated based on a differential value &#x394;i&#x3b1; of an &#x3b1;-axis current. Then a sensor phase reference current phase &#x3b8;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.

A reference current phase sensing part of a sensor phase (W) calculates an &#x3b1;-axis current i&#x3b1; and a &#x3b2;-axis current i&#x3b2; in a fixed coordinate system formed with respect to a sensor phase as a base. The &#x3b1;-axis current i&#x3b1; is calculated based on a sensed current iw.sns of the sensor phase and a &#x3b2;-axis current i&#x3b2; 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&#x3b8;=tan(i&#x3b2;/i&#x3b1;) 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&#x3b8; of the sensor phase and multiplying the sensed current iw.sns of the sensor phase by the estimation coefficient.

A control apparatus includes an electric current estimation unit to improve a responsiveness of an AC motor. The electric current estimation unit performs, at predetermined intervals, a dq conversion, a correction process, and an inverted dq conversion. The dq conversion calculates d/q axis electric current estimate values based on a detection value of a sensor phase from a sensor, and on an electric current estimate values of two phases of the AC motor other than the sensor phase from a previous cycle. The correction process corrects, during the dq conversion, the d/q axis electric current estimate values in an orthogonal direction that is orthogonal to a sensor phase axis. The inverted dq conversion calculates the electric current estimate values of the two phases other than the sensor phase based on the d/q axis electric current estimate values corrected by the correction process and smoothed by a low-pass filter process.

A control device for a three-phase AC motor includes: an inverter having switching elements; current sensors for sensing a current in the motor; and a control means having a feedback control operation part for operating a voltage command of each phase and switching the switching elements based on the voltage command. When a positive and negative offset abnormality occurs, the control means executes a positive and negative offset abnormality detection process that the control means compares a value, which is obtained by integrating a variation in a voltage command of each phase over a predetermined detection interval, with a predetermined abnormality threshold value, the voltage command being outputted by the feedback control operation part with respect to a variation in the current caused by the positive and negative offset abnormality.

Control device for AC motor

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 &#x3b1;-axis current and &#x3b2;-axis current in a stationary coordinate system defined by a &#x3b1;-axis parallel to the sensor phase axis and a &#x3b2;-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 &#x3b1;-axis current based on the detected current. The current estimation section calculates the &#x3b2;-axis current based on the detected current and a command value for the current flowing through the other phase of the motor.

Controller for AC motor

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.

Rotating electrical machine drive system

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.

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.

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.

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.

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 &#x3b8;e based on one phase. A phase is defined as &#x3c6; based on a dq axis. A phase angle of a current command vector is defined as (&#x3b8;e+&#x3c6;+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.

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Chita-gun, Japan

Hirofumi Kako