Motor control apparatus

• US 7,084,597 B2
• Filed: 05/23/2003
• Issued: 08/01/2006
• Est. Priority Date: 06/03/2002
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Kamio, Shigeru, Nakai, Yasuhiro
• Primary Examiner(s): Martin, David
• Assistant Examiner(s): MCCLOUD, RENATA D
• Application Number:
  US10/443,795
• Publication Number:
  US 20030222617A1
• Time in Patent Office: 1,166 Days
• Field of Search: None
• US Class Current: 318/254.1
• CPC Class Codes: F16H 2061/326 Actuators for range selection, i.e. actuators for controlling the range selector or the manual range valve in the transmission
• CPC Class Codes: F16H 61/32 Electric motors actuators or related electrical control means therefor
• CPC Class Codes: H02P 25/08 Reluctance motors
• CPC Class Codes: H02P 25/092 Converters specially adapted for controlling reluctance motors
• CPC Class Codes: H02P 25/0925 wherein the converter comprises only one switch per phase
• CPC Class Codes: H02P 8/42 characterised by non-stepper motors being operated step by step
• CPC Class Codes: Y10T 74/2003 Electrical actuator

Abstract

In an automatic transmission position control by a motor, it is determined whether the present instant belongs to a starting period, that is, the present instant is immediately after resetting of a control unit or application of power to it. If it is the starting period, an actual shift position that is detected from an output of an output shaft sensor for detecting a rotation position of a motor is set as an instructed shift position. With this measure, even if the control unit is reset for a certain reason while the vehicle is running, the instructed shift position is not changed in association with the resetting. This prevents trouble that the shift position is switched contrary to the intention of the driver, whereby the reliability of a position switching control can be increased.

Claims

1. A motor control apparatus comprising:

an encoder for producing a pulse output signal in synchronism with rotation of a rotor of a motor; and

control means for rotating the rotor by detecting a rotation position of the rotor on the basis of a count of the output signal of the encoder and sequentially switching a current supply phase of the motor;

wherein in an initial drive that is performed after application of power, the control means learns a corresponding relationship between a count of the output signal of the encoder, a rotation position of the rotor, and a current supply phase at an end of the initial drive by counting pulses of the output signal of the encoder by effecting current supply for all phases of the motor around according to a prescribed time schedule;

wherein in an ordinary drive that is performed after the initial drive, the control means determines a current supply phase on the basis of a count of the output signal of the encoder and a learning result that is obtained at the end of the initial drive;

wherein the motor is a switched reluctance motor, and wherein the control means performs one-phase current supply and two-phase current supply alternately in the initial drive; and

wherein the control means makes a time of the one-phase current supply shorter than that of the two-phase current supply.

2. The motor control apparatus according to claim 1, wherein the motor drives a position switching mechanism for switching between a parking position and another position of a vehicle.

3. A motor control apparatus comprising:

an encoder for producing a pulse output signal in synchronism with rotation of a rotor of a motor; and

control means for rotating the rotor by detecting a rotation position of the rotor on the basis of a count of the output signal of the encoder and sequentially switching a current supply phase of the motor;

wherein in an initial drive that is performed after application of power, the control means learns a corresponding relationship between a count of the output signal of the encoder, a rotation position of the rotor, and a current supply phase at an end of the initial drive by counting pulses of the output signal of the encoder by effecting current supply for all phases of the motor around according to a prescribed time schedule;

wherein in an ordinary drive that is performed after the initial drive, the control means determines a current supply phase on the basis of a count of the output signal of the encoder and a learning result that is obtained at the end of the initial drive;

wherein the motor is a switched reluctance motor, and wherein the control means performs one-phase current supply and two-phase current supply alternately in the initial drive; and

wherein the control means starts the initial drive from the two-phase current supply.

4. A motor control apparatus comprising:

an encoder for producing a pulse output signal in synchronism with rotation of a rotor of a motor; and

control means for rotating the rotor by detecting a rotation position of the rotor on the basis of a count of the output signal of the encoder and sequentially switching a current supply phase of the motor;

wherein in an initial drive that is performed after application of power, the control means learns a corresponding relationship between a count of the output signal of the encoder, a rotation position of the rotor, and a current supply phase at an end of the initial drive by counting pulses of the output signal of the encoder by effecting current supply for all phases of the motor around according to a prescribed time schedule;

wherein in an ordinary drive that is performed after the initial drive, the control means determines a current supply phase on the basis of a count of the output signal of the encoder and a learning result that is obtained at the end of the initial drive;

wherein the motor is a switched reluctance motor, and wherein the control means performs one-phase current supply and two-phase current supply alternately in the initial drive; and

wherein when finishing the initial drive halfway and making a transition to an ordinary drive are necessary, the control means causes a transition to an ordinary drive after completion of next two-phase current supply or after completion of current two-phase current supply if a transition to an ordinary drive has become necessary during the current two-phase current supply, learns a corresponding relationship between a count of the output signal of the encoder, a rotation position of the rotor, and a current supply phase at an end of the two-phase current supply, and determines, in the subsequent ordinary drive, a current supply phase on the basis of a count of the output signal of the encoder and a learning result that is obtained at the end of the two-phase current supply.

5. A motor control apparatus comprising:

an encoder for producing a pulse output signal in synchronism with rotation of a rotor of a motor; and

control means for rotating the rotor by detecting a rotation position of the rotor on the basis of a count of the output signal of the encoder and sequentially switching a current supply phase of the motor;

wherein in an initial drive that is performed after application of power, the control means learns a corresponding relationship between a count of the output signal of the encoder, a rotation position of the rotor, and a current supply phase at an end of the initial drive by counting pulses of the output signal of the encoder by effecting current supply for all phases of the motor around according to a prescribed time schedule;

wherein in an ordinary drive that is performed after the initial drive, the control means determines a current supply phase on the basis of a count of the output signal of the encoder and a learning result that is obtained at the end of the initial drive; and

wherein the encoder produces an A-phase signal and a B-phase signal that have a prescribed phase difference in synchronism with rotation of the rotor, and also produces a Z-phase signal in such a manner as to produce pulses at reference rotation positions of the rotor, and

wherein in the initial drive the control means learns a corresponding relationship between a count of the output signal of the encoder, a rotation position of the rotor, and a current supply phase at an end of the initial drive by counting edges of the A-phase signal and the B-phase signal, and in the subsequent ordinary drive the control means determines a current supply phase on the basis of a count of the output signal of the encoder and a learning result that is obtained at the end of the initial drive, determines whether a corresponding relationship between a count of the output signal of the encoder, a rotation position of the rotor, and a current supply phase at the time of output of a pulse of the Z-phase signal has a deviation, and performs a Z-phase correction of correcting a deviation if any.

6. The motor control apparatus according to claim 5, wherein the control means includes Z-phase correction prohibiting means for prohibiting further execution of the Z-phase correction if the Z-correction has been performed a prescribed number of times during the ordinary drive.

7. The motor control apparatus according to claim 5, wherein the control means performs the Z-phase correction by edge interruption processing on the A-phase signal or the B-phase signal.

8. A method of controlling a motor, the method comprising:

producing a pulse output signal in synchronism with rotation of a rotor of the motor; and

controlling rotation of the rotor, via a controller, by detecting a rotation position of the rotor on the basis of a count of the pulse output signal and sequentially switching a current supply phase of the motor;

wherein in an initial drive that is performed after application of power, the controller learns a corresponding relationship between a count of the pulse output signal, a rotation position of the rotor, and a current supply phase at an end of the initial drive by counting pulses of the pulse output signal by effecting current supply for all phases of the motor around according to a prescribed time schedule;

wherein in an ordinary drive that is performed after the initial drive, the controller determines a current supply phase on the basis of a count of the pulse output signal and a learning result that is obtained at the end of the initial drive;

wherein the motor is a switched reluctance motor, and wherein the controller performs one-phase current supply and two-phase current supply alternately in the initial drive; and

wherein the controller makes a time of the one-phase current supply shorter than that of the two-phase current supply.

9. The method according to claim 8, wherein the motor drives a position switching mechanism for switching between a parking position and another position of a vehicle.

10. A method of controlling a motor, the method comprising:

producing a pulse output signal in synchronism with rotation of a rotor of the motor; and

controlling rotation of the rotor, via a controller, by detecting a rotation position of the rotor on the basis of a count of the pulse output signal and sequentially switching a current supply phase of the motor;

wherein in an initial drive that is performed after application of power, the controller learns a corresponding relationship between a count of the pulse output signal, a rotation position of the rotor, and a current supply phase at an end of the initial drive by counting pulses of the pulse output signal by effecting current supply for all phases of the motor around according to a prescribed time schedule;

wherein in an ordinary drive that is performed after the initial drive, the controller determines a current supply phase on the basis of a count of the pulse output signal and a learning result that is obtained at the end of the initial drive;

wherein the motor is a switched reluctance motor, and wherein the controller performs one-phase current supply and two-phase current supply alternately in the initial drive; and

wherein the controller starts the initial drive from the two-phase current supply.

11. A method of controlling a motor, the method comprising:

producing a pulse output signal in synchronism with rotation of a rotor of the motor; and

controlling rotation of the rotor, via a controller, by detecting a rotation position of the rotor on the basis of a count of the pulse output signal and sequentially switching a current supply phase of the motor;

wherein in an initial drive that is performed after application of power, the controller learns a corresponding relationship between a count of the pulse output signal, a rotation position of the rotor, and a current supply phase at an end of the initial drive by counting pulses of the pulse output signal by effecting current supply for all phases of the motor around according to a prescribed time schedule;

wherein in an ordinary drive that is performed after the initial drive, the controller determines a current supply phase on the basis of a count of the pulse output signal and a learning result that is obtained at the end of the initial drive;

wherein the motor is a switched reluctance motor, and wherein the controller performs one-phase current supply and two-phase current supply alternately in the initial drive; and

wherein when finishing the initial drive halfway and making a transition to an ordinary drive are necessary, the controller causes a transition to an ordinary drive after completion of next two-phase current supply or after completion of current two-phase current supply if a transition to an ordinary drive has become necessary during the current two-phase current supply, learns a corresponding relationship between a count of the pulse output signal, a rotation position of the rotor, and a current supply phase at an end of the two-phase current supply, and determines, in the subsequent ordinary drive, a current supply phase on the basis of a count of the pulse output signal and a learning result that is obtained at the end of the two-phase current supply.

12. A method of controlling a motor, the method comprising:

producing a pulse output signal in synchronism with rotation of a rotor of the motor; and

controlling rotation of the rotor, via a controller, by detecting a rotation position of the rotor on the basis of a count of the pulse output signal and sequentially switching a current supply phase of the motor;

wherein in an initial drive that is performed after application of power, the controller learns a corresponding relationship between a count of the pulse output signal, a rotation position of the rotor, and a current supply phase at an end of the initial drive by counting pulses of the pulse output signal by effecting current supply for all phases of the motor around according to a prescribed time schedule;

wherein in an ordinary drive that is performed after the initial drive, the controller determines a current supply phase on the basis of a count of the pulse output signal and a learning result that is obtained at the end of the initial drive;

wherein producing the pulse output signal includes producing an A-phase signal and a B-phase signal that have a prescribed phase difference in synchronism with rotation of the rotor, and also producing a Z-phase signal in such a manner as to produce pulses at reference rotation positions of the rotor; and

wherein in the initial drive the controller learns a corresponding relationship between a count of the pulse output signal, a rotation position of the rotor, and a current supply phase at an end of the initial drive by counting edges of the A-phase signal and the B-phase signal, and in the subsequent ordinary drive the controller determines a current supply phase on the basis of a count of the pulse output signal and a learning result that is obtained at the end of the initial drive, determines whether a corresponding relationship between a count of the pulse output signal, a rotation position of the rotor, and a current supply phase at the time of output of a pulse of the Z-phase signal has a deviation, and performs a Z-phase correction of correcting a deviation if any.

13. The method according to claim 12, wherein the controller prohibits further execution of the Z-phase correction if the Z-correction has been performed a prescribed number of times during the ordinary drive.

14. The method according to claim 12, wherein the controller performs the Z-phase correction by edge interruption processing on the A-phase signal or the B-phase signal.