Motor driving control device and motor driving control method

Patent metadata

Field	Value
Publication number	US-11114961-B2
Application number	US-202016783271-A
Country	US
Kind code	B2
Filing date	Feb 6, 2020
Priority date	Feb 14, 2019
Publication date	Sep 7, 2021
Grant date	Sep 7, 2021

Abstract

A motor driving control device includes a motor driving unit, a position detection unit, a current detection unit and a control unit. The control unit includes a change detecting means configured to detect a predetermined phase change in the position signal, a first switching means configured to sequentially switch energization patterns of the coils with the plurality of phases based on a timing when the phase change is detected, and a second switching means configured to, in a state where the change detecting means does not detect the phase change, when a value of the drive current becomes a predetermined first threshold or more during a monitoring time period after a timing when the predetermined phase change in the position signal is expected, perform an operation to forcibly switch to a next energization pattern regardless of the timing of switching the energization pattern by the first switching means.

First claim

What is claimed is:

1. A motor driving control device comprising:
a motor driving unit having a plurality of switching elements connected to a power supply and configured to selectively energize coils with a plurality of phases of a motor;
a position detector corresponding to any one of the plurality of phases and configured to output a position signal, a phase of the position signal changing depending on a position of a rotor of the motor;
a current detector configured to detect a drive current of the motor; and
a control unit configured to output a drive control signal for operating the plurality of switching elements to the motor driving unit, wherein
the control unit includes
a change detecting means configured to detect a predetermined phase change in the position signal,
a first switching means configured to sequentially switch energization patterns of the coils with the plurality of phases based on a timing when the phase change is detected, and
a second switching means configured to, in a state where the change detecting means does not detect the phase change, when a value of the drive current becomes a predetermined first threshold or more during a monitoring time period after a timing when the predetermined phase change in the position signal is expected, perform an operation to forcibly switch to a next energization pattern regardless of the timing of switching the energization pattern by the first switching means.

2. The motor driving control device according to claim 1 , wherein
the control unit further includes a stopping means configured to stop driving of the motor in a case that the state where the change detecting means does not detect the phase change continues until a timing when the monitoring time period ends.

3. The motor driving control device according to claim 1 , wherein
the motor includes three-phase coils, and
a time from the timing when the predetermined phase change in the position signal is expected to the timing when the monitoring time period ends is longer than a time presumed to be taken for the rotor to rotate by 30 degrees in an electrical angle.

4. The motor driving control device according to claim 1 , wherein
a timing when the monitoring time period starts is a timing when a predetermined time elapses from the timing when the predetermined phase change in the position signal is expected.

5. The motor driving control device according to claim 1 , wherein
the control unit further includes an overcurrent restricting means configured to stop the energization by the motor driving unit when the value of the drive current exceeds a predetermined second threshold.

6. The motor driving control device according to claim 1 , wherein
the second switching means does not perform the operation to forcibly switch to the next energization pattern during a time period other than the monitoring time period.

7. A motor driving control method for driving a motor by use of
a motor driving unit having a plurality of switching elements connected to a power supply and configured to selectively energize coils with a plurality of phases of the motor,
a position detector corresponding to any one of the plurality of phases and configured to output a position signal, a phase of the position signal changing depending on a position of a rotor of the motor, and
a current detector configured to detect a drive current of the motor,
the method comprising:
a change detecting step of detecting a predetermined phase change in the position signal;
a first switching step of sequentially switching energization patterns of the coils with the plurality of phases based on a timing when the phase change is detected; and
a second switching step of, in a state where the change detecting step does not detect the phase change, when a value of the drive current becomes a predetermined first threshold or more during a monitoring time period after a timing when the predetermined phase change in the position signal is expected, forcibly performing an operation to switch to a next energization pattern regardless of the timing of switching the energization pattern by the first switching step.

Assignees

• Minebea Mitsumi Inc

Inventors

• Kaidu Hiroyuki
• Nogamida Wataru
• Aoki Masato

Classifications

• H02P6/20

  Arrangements for starting (H02P6/08 takes precedence) · CPC title

• H02P6/15 Primary

  Controlling commutation time · CPC title

• H02P6/085 Primary

  in a bridge configuration · CPC title

• H02P6/18

  without separate position detecting elements · CPC title

• H02P6/28

  Arrangements for controlling current (H02P6/10 takes precedence) · CPC title