Motor drive controller and motor drive control method

Patent metadata

Field	Value
Publication number	US-11005398-B2
Application number	US-201815983274-A
Country	US
Kind code	B2
Filing date	May 18, 2018
Priority date	May 24, 2017
Publication date	May 11, 2021
Grant date	May 11, 2021

Abstract

Provided is a motor drive controller capable of a locking energization operation while preventing increase in temperature of a coil. The motor drive controller includes a motor drive section selectively energizing coils with a plurality of phases of a motor and a locking energization control section. The locking energization control section performs a locking energization operation when the motor is started or restarted and holds a rotor of the motor in a position corresponding to the coil in which the lock current flows. In case of performing the locking energization operation, the locking energization control section switches a locking energization pattern for applying the lock current in the coil from a locking energization pattern when the preceding locking energization operation was performed. The locking energization control section controls the motor drive section so that the lock current flows in the coil in accordance with the switched locking energization pattern.

First claim

What is claimed is:

1. A motor drive controller comprising:
a motor drive section selectively energizing three-phase coils of a motor having first, second and third coils;
a locking energization control section performing a locking energization operation, in accordance with one of a plurality of locking energization patterns including first and second locking energization patterns, for controlling the motor drive section so that a lock current flows in all of the three-phase coils at the same time when the motor is started or restarted and stopping and holding a rotor of the motor in a position corresponding to the coils in which the lock current is flowing; and
a forced commutation control section performing a forced commutation operation for controlling the motor drive section by sequentially switching among a plurality of energization patterns in a predetermined order to rotate the rotor after the locking energization control section performs the locking energization operation,
wherein:
before the forced commutation operation, the locking energization control section performs the locking energization operation in accordance with the first locking energization pattern to stop the rotor in said position when the motor is started,
after the locking energization control section energizes the coils with the first locking energization pattern to stop the rotor in said position, the locking energization control section causes the forced commutation control section to perform the forced commutation operation, and
when the forced commutation operation doesn't succeed with the first locking energization pattern, the locking energization control section performs the locking energization operation by energizing the coils in accordance with the second locking energization pattern different from the first locking energization pattern, and causes the forced commutation control section to perform the forced commutation operation to restart rotation of the rotor, wherein
in the first locking energization pattern for stopping and holding the rotor in said position, the current flowing in the first coil is larger than those of the second and third coils, and
in the second locking energization pattern for stopping and holding the rotor in said position, the current flowing in the second coil is larger than those of the third and first coils.

2. The motor drive controller according to claim 1 , wherein the locking energization control section switches among the plurality of locking energization patterns in accordance with a predetermined switching pattern.

3. The motor drive controller according to claim 1 , wherein in case of performing the locking energization operation, the locking energization control section switches among the plurality of locking energization patterns when a predetermined switching condition is satisfied.

4. The motor drive controller according to claim 3 , wherein the predetermined switching condition includes whether the locking energization operation is performed a predetermined number of times n (n is an integer of 1 or more) or more in the same locking energization pattern.

5. The motor drive controller according to claim 1 , wherein the locking energization pattern used by the locking energization control section includes a combination of the coils with the plurality of phases in which the lock current flows.

6. The motor drive controller according to claim 5 , wherein the locking energization pattern used by the locking energization control section includes a combination of a phase into which the lock current flows and a phase from which the lock current flows.

7. The motor drive controller according to claim 1 , wherein the locking energization pattern used by the locking energization control section includes a combination of two phases into which the lock current flows and one phase from which the lock current flows.

8. The motor drive controller according to claim 1 , wherein the locking energization pattern used by the locking energization control section includes a combination of one phase into which the lock current flows and two phases from which the lock current flows.

9. The motor drive controller according to claim 1 , wherein upon performing the forced commutation operation, the forced commutation control section sets, as an initial energization pattern, an energization pattern in accordance with the locking energization pattern used by the locking energization control section when the locking energization operation was performed.

10. The motor drive controller according to claim 9 , wherein upon performing the forced commutation operation, the forced commutation control section sets, as an initial energization pattern, an energization pattern advanced in the predetermined order in accordance with the locking energization pattern used by the locking energization control section when the locking energization operation was performed.

11. The motor drive controller according to claim 1 , wherein the motor drive controller performs the locking energization operation in a position-sensorless manner.

12. A method of driving a motor by controlling a motor drive section selectively energizing three-phase coils with a plurality of phases of the motor having first, second and third coils, the method comprising:
performing a locking energization operation in accordance with a first locking energization pattern for controlling the motor drive section by energizing the coils with the first locking energization pattern so that a lock current flows in all of the three-phase coils at the same time when the motor is started or restarted and stopping and holding a rotor of the motor in a position corresponding to the coil in which the lock current is flowing; and
driving the motor by performing a forced commutation operation for controlling the motor drive section by switching among a plurality of energization patterns in a predetermined order, after the locking energization operation is performed,
wherein
before the forced commutation operation, the locking energization control section performs the locking energization operation in accordance with the first locking energization pattern to stop the rotor in said position when the motor is started,
after the locking energization control section energizes the coils with the first locking energization pattern to stop the rotor in said position, the locking energization control section causes the forced commutation control section to perform the forced commutation operation, when the forced commutation operation doesn't succeed with the first locking energization pattern, performing a second locking energization operation by energizing the coils in accordance with a second locking energization pattern different form the first locking energization pattern, and causing the forced commutation control section to perform the forced commutation operation to restart rotation of the rotor,
wherein
in the first locking energization pattern for stopping and holding the rotor in said position the current flowing in the first coil is larger than those of the second and third coils, and
in the second locking energization pattern for stopping and holding the rotor in said position the current flowing in the second coil is larger than those of the third and first coils.

13. The method according to claim 12 , wherein the locking energization operation is performed in a position-sensorless manner.

Assignees

• Minebea Mitsumi Inc

Inventors

• Kaidu Hiroyuki
• Serizawa Youhei
• Harigae Shunsuke
• Xiao Zhou

Classifications

• H02P6/24

  Arrangements for stopping · CPC title

• H02P6/21 Primary

  Open loop start · CPC title

• H02P29/02 Primary

  Providing protection against overload without automatic interruption of supply (protection against faults of stepper motors H02P8/36) · CPC title

• H02P1/026

  Means for delayed starting · CPC title

• H02P29/64

  Controlling or determining the temperature of the winding · CPC title