MOTOR CONTROL DEVICE AND MOTOR CONTROL METHOD

• US 20200136543A1
• Filed: 10/25/2019
• Published: 04/30/2020
• Est. Priority Date: 10/29/2018
• Status: Active Grant

• Current Assignee: Jtekt Corporation (Toyota Motor Corporation), Jtekt Europe S.A.S. (Toyota Motor Corporation)
• Original Assignee: Jtekt Corporation (Toyota Motor Corporation)
• Inventors: KAWAMURA, Hiroshi, FUJITA, Yuji, PALANDRE, Xavier, SLAMA, Tahar
• Granted Patent: US 11,251,732 B2
• Time in Patent Office: Days
• CPC Class Codes: B62D 5/0409 Electric motor acting on the steering column
• CPC Class Codes: B62D 5/0463 calculating assisting torque from the motor based on driver input
• CPC Class Codes: H02P 1/04 Means for controlling progress of starting sequence in dependence upon time or upon current, speed, or other motor parameter
• CPC Class Codes: H02P 21/06 Rotor flux based control involving the use of rotor position or rotor speed sensors
• CPC Class Codes: H02P 21/20 Estimation of torque
• CPC Class Codes: H02P 21/22 Current control, e.g. using a current control loop
• CPC Class Codes: H02P 25/03 with brushless excitation
• CPC Class Codes: H02P 25/26 with arrangements for controlling secondary impedance
• CPC Class Codes: H02P 6/08 Arrangements for controlling the speed or torque of a single motor H02P6/10, H02P6/28 take precedence
• CPC Class Codes: H02P 6/12 Monitoring commutation; Providing indication of commutation failure
• CPC Class Codes: H02P 6/28 Arrangements for controlling current H02P6/10 takes precedence
• CPC Class Codes: H02P 6/32 Arrangements for controlling wound field motors, e.g. motors with exciter coils

Abstract

A motor control device includes processing circuitry configured to calculate a current command value corresponding to torque that should be generated by a motor, divide the calculated current command value into individual current command values for coil groups, control power feeding to the coil groups independently for each of the coil groups based on a corresponding one of the individual current command values, set, for each one of the coil groups, an upper limit value of a corresponding one of the individual current command values and, when the individual current command value for any one of the coil groups is limited to a value that is smaller than a corresponding one of the upper limit values, supplement an amount limited in the individual current command value by increasing the individual current command value for at least a remaining one of the coil groups.

Claims

1. A motor control device that controls a motor including coil groups, the motor control device comprising processing circuitry, wherein

the processing circuitry is configured to:

calculate a current command value corresponding to torque that should be generated by the motor;

divide the calculated current command value into individual current command values for the coil groups;

control power feeding to the coil groups independently for each of the coil groups based on a corresponding one of the individual current command values;

set, for each one of the coil groups, an upper limit value of a corresponding one of the individual current command values; and

when the individual current command value for any one of the coil groups is limited to a value that is smaller than a corresponding one of the upper limit values, supplement an amount limited in the individual current command value by increasing the individual current command value for at least a remaining one of the coil groups.

2. The motor control device according to claim 1, wherein the processing circuitry is configured such that in a case in which none of the individual current command values for the coil groups is limited, when the current command value exceeds the upper limit value of the individual current command value for any one of the coil groups, the processing circuitry sets an amount exceeding the upper limit value of the current command value to the individual current command value for the remaining one coil group or distributes an amount exceeding the upper limit value of the current command value to the individual current command values for the remaining coil groups.

3. The motor control device according to claim 1, wherein the processing circuitry is configured such that in a case in which none of the individual current command values for the coil groups is limited, the processing circuitry equally distributes the current command value to the individual current command values for the coil groups.

4. The motor control device according to claim 1, wherein the processing circuitry is configured to:

calculate, for each of the coil groups, a difference between the individual current command value prior to being limited for each of the coil groups and an actual value of current supplied to each of the coil groups; and

add the difference calculated for each of the coil groups to the individual current command value for at least another one of the coil groups that differs from a corresponding one of the coil groups.

5. The motor control device according to claim 1, wherein the upper limit values of the individual current command values for the coil groups are each set to a value that is obtained by equally dividing, by the number of the coil groups, the current command value corresponding to a maximum torque that can be generated by the motor.

6. The motor control device according to claim 1, wherein the processing circuitry includes the same number of individual controllers as the number of the coil groups, the individual controllers being configured to control power feeding to the coil groups independently for each of the coil groups.

7. The motor control device according to claim 1, wherein

the motor is configured to generate torque given to a steering mechanism for a vehicle, and

the processing circuitry is configured to calculate the current command value based on a steering torque.

8. A motor control method for controlling a motor including coil groups, the motor control method comprising:

calculating a current command value corresponding to torque that should be generated by the motor;

dividing the calculated current command value into individual current command values for the coil groups;

controlling power feeding to the coil groups independently for each of the coil groups based on a corresponding one of the individual current command values;

setting, for each one of the coil groups, an upper limit value of a corresponding one of the individual current command values; and

when the individual current command value for any one of the coil groups is limited to a value that is smaller than a corresponding one of the upper limit values, supplementing an amount limited in the individual current command value by increasing the individual current command value for at least a remaining one of the coil groups.