Motor drive control device and method for controlling the same

Patent metadata

Field	Value
Publication number	US-11515814-B2
Application number	US-202117491598-A
Country	US
Kind code	B2
Filing date	Oct 1, 2021
Priority date	Oct 6, 2020
Publication date	Nov 29, 2022
Grant date	Nov 29, 2022

Abstract

To provide a motor drive control device capable of determining the rotational direction of a motor using a simple configuration with a reduced number of lead wires from position sensors, and a method for controlling the motor drive control device. A control circuit unit of a motor drive control device includes a first comparator configured to compare the magnitudes of a first positive Hall signal and a first negative Hall signal output from a first Hall element, thereby generating a first position detection signal; a second comparator configured to compare the magnitudes of a second negative Hall signal output from a second Hall element and the first negative Hall signal, thereby generating a second position detection signal; and a rotational direction determination unit configured to compare the transitions of the first position detection signal and the second position detection signal, thereby determining the rotational direction of a motor.

First claim

What is claimed is:

1. A motor drive control device comprising:
a motor drive unit configured to drive a motor; and
a control circuit unit configured to output a drive control signal to the motor drive unit,
wherein:
the control circuit unit includes
a first comparison element configured to compare magnitudes of a positive output signal and a negative output signal output from a first Hall element, thereby generating a first polarity signal, the first Hall element being provided at a first position where a change in a magnetic flux generated with a rotation of the motor is detectable,
a second comparison element configured to compare a magnitude of a positive or negative output signal output from a second Hall element and a magnitude of a comparison signal for a target to be compared, thereby generating a second polarity signal, the second Hall element being provided at a second position where a change in a magnetic flux generated with a rotation of the motor is detectable, and
a rotational direction determination unit configured to compare a transition of the first polarity signal and a transition of the second polarity signal, thereby determining a rotational direction of the motor.

2. The motor drive control device according to claim 1 , wherein the rotational direction determination unit is configured to, when a polarity of one of the first polarity signal and the second polarity signal has changed, determine the rotational direction of the motor based on a result of comparison between a direction of the change in the polarity of the one of the first polarity signal and the second polarity signal and a polarity of another polarity signal at the change.

3. The motor drive control device according to claim 2 , wherein the second comparison element uses as the comparison signal the positive output signal or the negative output signal output from the first Hall element.

4. The motor drive control device according to claim 2 , wherein the second comparison element uses as the comparison signal a signal with a predetermined reference voltage.

5. The motor drive control device according to claim 3 , wherein the rotational direction determination unit is configured to
determine that rotation of the motor is forward rotation if the second polarity signal has a second polarity at a timing when the polarity of the first polarity signal changes from a first polarity to the second polarity and also if the second polarity signal has the first polarity at a timing when the polarity of the first polarity signal changes from the second polarity to the first polarity, and
determine that rotation of the motor is reverse rotation if the second polarity signal has the first polarity at a timing when the polarity of the first polarity signal changes from the first polarity to the second polarity and also if the second polarity signal has the second polarity at a timing when the polarity of the first polarity signal changes from the second polarity to the first polarity.

6. The motor drive control device according to claim 3 , wherein the rotational direction determination unit is configured to
determine that rotation of the motor is forward rotation if the second polarity signal has a first polarity at a timing when the polarity of the first polarity signal changes from a second polarity to the first polarity and also if the second polarity signal has the second polarity at a timing when the polarity of the first polarity signal changes from the first polarity to the second polarity, and
determine that rotation of the motor is reverse rotation if the second polarity signal has the second polarity at a timing when the polarity of the first polarity signal changes from the second polarity to the first polarity and also if the second polarity signal has the first polarity at a timing when the polarity of the first polarity signal changes from the first polarity to the second polarity.

7. The motor drive control device according to claim 4 , wherein the rotational direction determination unit is configured to
determine that rotation of the motor is forward rotation if the first polarity signal has a second polarity at a timing when the polarity of the second polarity signal changes from the second polarity to a first polarity and also if the first polarity signal has the first polarity at a timing when the polarity of the second polarity signal changes from the first polarity to the second polarity, and
determine that rotation of the motor is reverse rotation if the second polarity signal has the first polarity at a timing when the polarity of the second polarity signal changes from the second polarity to the first polarity and also if the first polarity signal has the second polarity at a timing when the polarity of the second polarity signal changes from the first polarity to the second polarity.

8. The motor drive control device according to claim 1 , wherein the rotational direction determination unit is configured to determine the rotational direction of the motor based on a timing when a polarity of the second polarity signal changes within half a period of a change in the first polarity signal.

9. A method for controlling a motor drive control device, the motor drive control device including a motor drive unit configured to drive a motor, and a control circuit unit configured to output a drive control signal to the motor drive unit, the method comprising:
a first comparison step of comparing a magnitude of a positive output signal and a magnitude of a negative output signal output from a first Hall element, thereby generating a first polarity signal, the first Hall element being provided at a first position where a change in a magnetic flux generated with a rotation of the motor is detectable;
a second comparison step of comparing a magnitude of a positive or negative output signal output from a second Hall element and a magnitude of a comparison signal for a target to be compared, thereby generating a second polarity signal, the second Hall element being provided at a second position where a change in a magnetic flux generated with a rotation of the motor is detectable; and
a rotational direction determination step of comparing a transition of the first polarity signal and a transition of the second polarity signal, thereby determining a rotational direction of the motor.

Assignees

• Minebea Mitsumi Inc

Inventors

• Aoki Masato
• Suzuki Takahiro
• Sakuma Tomotaka

Classifications

• H02P6/16 Primary

  Circuit arrangements for detecting position · CPC title

• H02P6/17

  and for generating speed information · CPC title