Motor control device, motor device, and program

• US 10,642,245 B2
• Filed: 09/26/2018
• Issued: 05/05/2020
• Est. Priority Date: 01/24/2018
• Status: Active Grant

• Current Assignee: Mabuchi Motor Company Limited
• Original Assignee: Mabuchi Motor Company Limited
• Inventors: Fukuhara, Kazuki, Sakamoto, Kentaro
• Primary Examiner(s): Masih, Karen
• Application Number:
  US16/142,383
• Publication Number:
  US 20190227517A1
• Time in Patent Office: 587 Days
• CPC Class Codes: A61M 2005/31588 electrically driven
• CPC Class Codes: A61M 2205/3317 Electromagnetic, inductive or dielectric measuring means
• CPC Class Codes: A61M 2205/3365 Rotational speed
• CPC Class Codes: A61M 2205/50 with microprocessors or computers
• CPC Class Codes: A61M 5/31576 Constructional features or modes of drive mechanisms for piston rods
• CPC Class Codes: G05B 19/402 characterised by control arrangements for positioning, e.g. centring a tool relative to a hole in the workpiece, additional detection means to correct position G05B19/19 takes precedence
• CPC Class Codes: G05B 2219/34013 Servocontroller
• CPC Class Codes: H02P 2203/05 Determination of the rotor position by using two different methods and/or motor models
• CPC Class Codes: H02P 29/00 Arrangements for regulating or controlling electric motors, appropriate for both AC and DC motors arrangements for starting electric motors H02P1/00; arrangements for stopping or slowing electric motors H02P3/00; control of motors that can be connected to two or more different electric power supplies H02P4/00; regulating or controlling the speed or torque of two or more electric motors H02P5/00; vector control H02P21/00
• CPC Class Codes: H02P 29/024 Detecting a fault condition, e.g. short circuit, locked rotor, open circuit or loss of load
• CPC Class Codes: H02P 6/16 Circuit arrangements for detecting position

Abstract

A motor control device includes: a rotational position calculator that calculates a rotational position of a motor that rotates a rotor; an operation state controller that controls a state of supply of operation power to the rotational position calculator; a deviation calculator that calculates a deviation of a rotational position of the rotor on the basis of a stop target rotational position of the rotor and the rotational position of the rotor after supply of a drive current to a coil is stopped and before supply of operation power to the rotational position calculator is stopped; a storage controller that stores the deviation on a storage; a rotational position control signal generator that generates a rotational position control signal for controlling the rotational position of the rotor on the basis of the deviation stored on the storage and the stop target rotational position of the rotor; and a drive current output unit that outputs the drive current to the coil on the basis of the rotational position control signal after supply of operation power to the rotational position calculator is restarted by the operation state controller.

Claims

1. A motor control device comprising:

a rotational position calculator configured to calculate a rotational position of a motor that rotates a rotor with an interaction of magnetic force between a magnetic body around which a coil through which a drive current flows is wound and a permanent magnet;

an operation state controller configured to control a state of supply of operation power to the rotational position calculator;

a deviation calculator configured to calculate a deviation of a rotational position of the rotor based on a stop target rotational position of the rotor and the rotational position of the rotor calculated by the rotational position calculator after supply of the drive current to the coil is stopped and before supply of operation power to the rotational position calculator is stopped by the operation state controller;

a storage controller configured to store the deviation calculated by the deviation calculator on a storage after supply of the drive current to the coil is stopped;

a rotational position control signal generator configured to generate a rotational position control signal for controlling the rotational position of the rotor based on the deviation stored by the storage controller on the storage after supply of the drive current to the coil is stopped and the stop target rotational position of the rotor; and

a drive current output unit configured to output the drive current to the coil based on the rotational position control signal generated by the rotational position control signal generator after supply of operation power to the rotational position calculator is restarted by the operation state controller.

2. The motor control device according to claim 1, wherein the rotational position calculator calculates the rotational position when predetermined time elapses after supply of the drive current to the coil is stopped.

3. The motor control device according to claim 1, wherein the deviation calculator calculates the deviation in a case where a time change in the rotational position calculated by the rotational position calculator after supply of the drive current to the coil is stopped and before supply of operation power to the rotational position calculator is stopped by the operation state controller is equal to or less than a predetermined value.

4. The motor control device according to claim 3, wherein:

the deviation calculator restarts supply of the drive current to the coil in a case where the time change in the rotational position calculated by the rotational position calculator after supply of the drive current to the coil is stopped and before supply of operation power to the rotational position calculator is stopped by the operation state controller is larger than the predetermined value; and

the rotational position calculator calculates the rotational position after supply of the drive current to the coil is restarted.

5. A motor device comprising the motor control device according to claim 1.

6. The motor control device according to claim 2, wherein the deviation calculator calculates the deviation in a case where a time change in the rotational position calculated by the rotational position calculator after supply of the drive current to the coil is stopped and before supply of operation power to the rotational position calculator is stopped by the operation state controller is equal to or less than a predetermined value.

8. The motor control device according to claim 6, wherein:

the deviation calculator restarts supply of the drive current to the coil in a case where the time change in the rotational position calculated by the rotational position calculator after supply of the drive current to the coil is stopped and before supply of operation power to the rotational position calculator is stopped by the operation state controller is larger than the predetermined value; and

the rotational position calculator calculates the rotational position after supply of the drive current to the coil is restarted.

7. A non-transitory computer-readable medium storing a program for causing a computer to execute:

a rotational position calculation step of calculating a rotational position of a motor that rotates a rotor with an interaction of magnetic force between a magnetic body around which a coil through which a drive current flows is wound and a permanent magnet;

an operation state control step of controlling a state of supply of operation power in the rotational position calculation step;

a deviation calculation step of calculating a deviation of a rotational position of the rotor based on a stop target rotational position of the rotor and the rotational position of the rotor calculated in the rotational position calculation step after supply of the drive current to the coil is stopped and before supply of operation power in the rotational position calculation step is stopped in the operation state control step;

a storage control step of storing the deviation calculated in the deviation calculation step on a storage after supply of the drive current to the coil is stopped;

a rotational position control signal generation step of generating a rotational position control signal for controlling the rotational position of the rotor based on the deviation stored on the storage after supply of the drive current to the coil is stopped in the storage control step and the stop target rotational position of the rotor; and

a drive current output step of outputting the drive current to the coil based on the rotational position control signal generated in the rotational position control signal generation step after supply of operation power in the rotational position calculation step is restarted by the operation state control step.