Rotation drive control circuit of multiphases direct current motor and the start-up method thereof

• US 7,071,640 B2
• Filed: 10/15/2003
• Issued: 07/04/2006
• Est. Priority Date: 10/21/2002
• Status: Expired due to Fees

• Current Assignee: Hitachi ULSI Systems Company Limited (Hitachi, Ltd.), Renesas Electronics Corporation
• Original Assignee: Hitachi ULSI Systems Company Limited (Hitachi, Ltd.), Renesas Technology Corporation (Renesas Electronics Corporation)
• Inventors: Kurosawa, Minoru, Kokami, Yasuhiko, Kawauchi, Kunihiro
• Primary Examiner(s): Ro, Bentsu
• Application Number:
  US10/684,380
• Publication Number:
  US 20040080293A1
• Time in Patent Office: 993 Days
• Field of Search: 318/138, 318/254, 318430-434, 318720-724, 318/439
• US Class Current: 318/400.04
• CPC Class Codes: H02M 1/0009 Devices or circuits for detecting current in a converter
• CPC Class Codes: H02M 7/5395 by pulse-width modulation
• CPC Class Codes: H02P 6/182 using back-emf in windings
• CPC Class Codes: H02P 6/20 Arrangements for starting H02P6/08 takes precedence

Abstract

In start-up control of a motor in which currents are caused to flow through any two of three phase coils to detect the polarity of a voltage induced in each de-energized phase, thereby determining the corresponding energized phase at start-up thereof, based on the polarity of the detected induced voltage, the levels of induced voltages are detected in addition to the polarity of the induced voltage for the de-energized phase to thereby determine the relationship between the magnitudes thereof, and the energized phase at the start-up is determined based on the relationship of magnitude between the polarity of each induced voltage and the level thereof. In drive control of a multi-phase DC motor wherein a driver for allowing a drive current to flow through each coil is controlled by PWM control signals, and a sine wave-shaped current is caused to flow through each coil to thereby rotatably drive the motor, positive-phase and negative-phase signals are generated as triangular wave carrier signals for generating the PWM control signals, and the PWM control signal related to the corresponding phase coil of the respective phase coils, to which a voltage of an intermediate level is applied by the driver, is generated using a carrier signal opposite in phase to a triangular wave signal used to generate the PWM control signals for other phase coils.

Claims

1. A rotation drive control device of a three-phase DC motor comprising:

a drive control unit; and

a three-phase DC motor including three-phase coils and a rotor,

wherein the drive control unit generates a first current that flows through each of any two phases of the three-phase coils to detect a polarity of an induced voltage induced in a de-energized phase of the three-phase coils so as to determine a direction of energization and corresponding two phase coils through which a second current flows to rotate the rotor,

wherein the drive control unit controls a start-up of the three-phase DC motor based upon a first determination in connection with the direction of energization and the corresponding two phase coils,

wherein the rotor does not respond to the first current,

wherein when the drive control unit determines that any two detected levels of the induced voltages are larger than a predetermined level, the drive control unit determines the direction of energization and the corresponding two phase coils by using two detected polarities of the induced voltages in connection with said any two detected levels, so as to rotate the rotor based upon the direction of energization and the corresponding two phase coils thereof are determined, and

wherein when the drive control unit determinates that said any two detected levels in connection with the induced voltages are larger than the predetermined level, the drive control unit determines the direction of the energization and the corresponding two phase coils by ignoring a detection result of a polarity of an induced voltage of the de-energized phase of the three-phase coils whose induced voltage is smaller than the predetermined level.

2. The rotation drive control device of three-phase DC motor according to claim 1,

wherein the drive control unit includes a comparator or an arithmetic circuit which determines whether a detected level of the induced voltage of each de-energized phase of the three-phase coils is larger or smaller than the predetermined level, and registers which store the results of determination every phases together with the polarity of the induced voltage in each de-energized phase of the three phase coils.

3. The rotation drive control device of three-phase DC motor according to claim 2,

wherein the drive control unit further includes a decoder which decodes outputs of the registers and outputs a signal indicative in connection with the direction of energization and corresponding two phase coils.

4. The rotation drive control device of three-phase DC motor according to claim 3,

wherein the drive control unit further includes a rotation determining unit which compares a previous output of the signal indicative with a present output of the signal indicative so as to determine normal rotation or reverse rotation of the rotor.

5. A method of starting up a three-phase DC motor including three-phase coils and a rotor, comprising:

generating a first current to flow through each of any two phases of the three-phase coils to detect a polarity of an induced voltage induced in a de-energized phase of the three-phase coils by a drive control unit driving and controlling the three-phase DC motor, thereby determining a direction of energization and corresponding two phase coils through which a second current flows to rotate the rotor;

based upon determining that any two detected levels of the induced voltages are larger than a predetermined level, determining the direction of energization and the corresponding two phase coils by using two detected polarities of the induced voltages in connection with said any two detected levels thereby rotating the rotor based upon the direction of energization and the corresponding two phase coils thereof are determined; and

driving the three-phase DC motor based upon a first determination in connection with the direction of the energization and the corresponding two phase coils,

wherein the rotor does not response by the first current, and

wherein when the drive control unit determinates that said any two detected levels in connection with the induced voltages are larger than the predetermined level, the drive control unit determines the direction of the energization and the corresponding two phase coils by ignoring a detection result of a polarity of an induced voltage of the de-energized phase of the three-phase coils whose induced voltage is smaller than the predetermined level.

6. The method according to claim 5, further comprising steps of:

comparing a previous output of a signal indicative in connection with the direction of energization and the corresponding two phase coils with a present output of the signal indicative in connection with the direction of energization and the corresponding two phase coils thereby determining normal rotation or reverse rotation of the rotor.

7. The method of starting up a three-phase DC motor according to claim 5,

further comprising a step of energizing based on the direction of the energization and the corresponding two phase coils by detecting only a polarity of an one phase which is respected subsequent the polarity changed so as to rotate the rotor after determining normally rotation of the rotor.

8. The method of starting up a three-phase DC motor according to claim 7,

further comprising a step of confirming whether the rotor is rotated at a predetermined electrical degrees or a predetermined number of times or more so as to proceed to the step of energizing.

9. A rotation drive control system of a three-phase DC motor comprising:

a drive control unit including a driver, a current detection unit, a PWM signal generator and a vector controller;

the PWM signal generator including a triangular wave generator, and a comparison unit; and

a three-phase DC motor including three-phase coils and a rotor,

wherein the drive control unit generates a current command value,

wherein the current detection unit executes a current detection of a current which flows through the three-phase coils,

wherein the vector controller generates a first indicative voltage corresponding to a first phase of the three-phase coils, a second indicative voltage corresponding to a second phase of the three-phase coils and a third indicative voltage corresponding to a third phase of the three-phase coils by detecting a difference between a result of the current detection and the current command value,

wherein the PWM signal generator generates and outputs a first PWM signal, a second PWM signal, and a third PWM signal,

wherein the driver drives the three-phase DC motor based on the first PWM signal, the second PWM signal, and the third PWM signal,

wherein the triangular wave generator generates a positive phase triangular wave and a negative phase triangular wave, and

wherein when the first indicative voltage is an intermediate potential between a voltage value of the second indicative voltage and a voltage value of the third indicative voltage and changes between the voltage values of the second and third indicative voltages, the first PWM signal is generated by the comparison unit which compares the negative phase triangular wave with the first indicative voltage, and the second PWM signal is generated by the comparison unit which compares the positive phase triangular wave with the second indicative voltage,

wherein when the second indicative voltage is an intermediate potential between a voltage value of the first indicative voltage and a voltage value of the third indicative voltage and changes between the voltage values of the first and third indicative voltages, the second PWM signal is generated by the comparison unit which compares the negative phase triangular wave with the second indicative voltage, and the first PWM signal is generated by the comparison unit which compares the positive phase triangular wave with the first indicative voltage.

10. The rotation drive control system of three-phase DC motor according to claim 9,

wherein the drive control unit further includes a sample-and-hold signal generator,

wherein when the third indicative voltage is an intermediate potential between a voltage value of the second indicative voltage and a voltage value of the first indicative voltage and changes between the voltage values of the second and first indicative voltages, the third PWM signal is generated by the comparison unit which compares the negative phase triangular wave with the third indicative voltage, the second PWM signal is generated by the comparison unit which compares the positive phase triangular wave with the second indicative voltage, and the first PWM signal is generated by the comparison unit which compares the positive phase triangular wave with the first indicative voltage,

wherein when the first indicative voltage is the intermediate potential between the voltage value of the second indicative voltage and the voltage value of the third indicative voltage and changes between the voltage values of the second and third indicative voltages, the sample-and-hold signal generator generates a sample-and-hold signal to synchronize with each of rising edges and falling edges of the first PWM signal, so as to give a detection timing in connection with the current detection,

wherein when the second indicative voltage is the intermediate potential between the voltage value of the first indicative voltage and the voltage value of the third indicative voltage and changes between the voltage values of the first and third indicative voltages, the sample-and-hold signal generator generates a sample-and-hold signal to synchronize with each of rising edges and falling edges of the second PWM signal, so as to give a detection timing in connection with the current detection,

wherein when the third indicative voltage is the intermediate potential between the voltage value of the second indicative voltage and the voltage value of the first indicative voltage and changes between the voltage values of the second and first indicative voltages, the sample-and-hold signal generator generates a sample-and-hold signal to synchronize with each of rising edges and falling edges of the third PWM signal, so as to give a detection timing in connection with the current detection.

11. The rotation drive control system of three-phase DC motor according to claim 9, wherein the third indicative voltage is set as a first fixed signal so as to set the third PWM signal as a second fixed signal to a 100% or 0% duty.

12. The rotation drive control system of three-phase DC motor according to claim 11,

wherein the drive control unit includes a sample-and-hold signal generator which generates a sample-and-hold signal to synchronize with each of peak points of the positive phase triangular wave and the negative phase triangular wave so as to provide a detection timing in connection with the current detection.

13. A rotation drive control device of three-phase DC motor, comprising:

a drive control unit; and

a three-phase DC motor including three-phase coils and a rotor,

wherein the drive control unit generates a first current that flows through each of any two phases of the three-phase coils to detect a polarity of an induced voltage induced in a de-energized phase of the three-phase coils so as to determine a direction of energization and corresponding two phase coils through which a second current flows to rotate the rotor,

wherein the drive control unit controls a start-up of the three-phase DC motor based upon a first determination in connection with the direction of energization and the corresponding two phase coils,

wherein the rotor does not respond to the first current,

wherein when the drive control unit determines that any two detected levels of the induced voltages are larger than a predetermined level, the drive control unit determines the direction of energization and the corresponding two phase coils by using two detected polarities of the induced voltages in connection with said any two detected levels, so as to rotate the rotor based upon the direction of energization and the corresponding two phase coils thereof are determined, and

wherein when the drive control unit determinates that said two detected levels of the induced voltages are larger than the predetermined level, the drive control unit determines the direction of the energization and the corresponding two phase coils by inverting a detection result of a polarity of an induced voltage of a de-energized phase of the three-phase coils whose induced voltage is smaller than the predetermined level.

14. A rotation drive control device of a three-phase DC motor comprising:

a three-phase DC motor including three-phase coils and a rotor,

a drive unit which generates a first current that flows through two phases of the three-phase coils to detect a polarity of an induced voltage in a de-energized phase of the three-phase coils; and

a magnetic pole position detecting unit which determines a direction of energization and corresponding two phase coils by using any two detected levels in connection with the induced voltages in any two phase coils of the three-phase DC motor, when the magnetic pole position detecting unit determines that said any two detected levels are larger than a reference level,

wherein through the corresponding two phase coils, a second current flows to rotate the rotor, and

wherein when the drive control unit determinates that said two detected levels of the induced voltages are larger than the predetermined level, the drive control unit determines the direction of the energization and the corresponding two phase coils by inverting a detection result of a polarity of an induced voltage of the de-energized phase of the three-phase coils whose induced voltage is smaller than the predetermined level.

15. A rotation drive control device of a three-phase DC motor according to claim 14,

wherein the drive unit generates the second current, and

wherein the rotor does not respond to the first current.

16. A rotation drive control device of a three-phase DC motor according to claim 15,

further comprising a rotation determining unit for determining a normal rotation or a reverse rotation of the rotor based on a present output and a previous output of an indicative signal in connection with the direction of energization and the corresponding two phase coils.

17. A rotation drive control device of a three-phase DC motor, comprising:

a three-phase DC motor including three-phase coils and a rotor,

a drive unit which generates a first current that flows through two phases of the three-phase coils to detect a polarity of an induced voltage in a de-energized phase of the three-phase coils; and

a magnetic pole position detecting unit which determines a direction of energization and corresponding two phase coils by using any two detected levels in connection with the induced voltages in any two phase coils of the three-phase DC motor, when the magnetic pole position detecting unit determines that said any two detected levels are larger than a reference level,

wherein through the corresponding two phase coils, a second current flows to rotate the rotor, and

wherein when the magnetic pole position detecting unit determinates that said any two detected levels are larger than the reference level, the magnetic pole position detecting unit determines the direction of the energization and the corresponding two phase coils by ignoring a detection result of a polarity of the induced voltage of an de-energized phase of the three-phase coils, the de-energized phase whose the induced voltage is smaller than the reference level.

18. A rotation drive control system of a three-phase DC motor comprising:

a three-phase DC motor including three-phase coils;

a current detection unit which executes a current detection of a current which flows through the three-phase coils so as to generate a first indicative voltage corresponding to a first phase of the three-phase coils, a second indicative voltage corresponding to a second phase of the three-phase coils, and a third indicative voltage corresponding to a third phase of the three-phase coils; and

a PWM signal generator which generates a first PWM signal by comparing a negative phase triangular wave with the first indicative voltage and a second PWM signal by comparing a positive phase triangular wave with the second indicative voltage, when the first indicative voltage is between the second indicative voltage and the third indicative voltage, said PWM signal generator generating the second PWM signal by comparing a negative phase triangular wave with the second indicative voltage and the first PWM signal by comparing a positive phase triangular wave with the first indicative voltage, when the second indicative voltage is between the first indicative voltage and the third indicative voltage.

19. A rotation drive control system of a three-phase DC motor according to claim 18, further comprising a driver which drives the three-phase DC motor based on the first PWM signal, the second PWM signal, and a third PWM signal.

20. A rotation drive control system of a three-phase DC motor according to claim 19,

wherein the current detection unit includes a vector controller which generates the first indicative voltage, the second indicative voltage, and the third indicative voltage by detecting a difference between a result of the current detection and a current command value from a controller.

21. A rotation drive control system of a three-phase DC motor according to claim 19,

wherein the PWM signal generator includes a triangular wave generator which generates the positive phase triangular wave and the negative phase triangular wave, and a comparison unit which compares one of the indicative voltages with one of the triangular waves so as to generate the PWM signal.

22. A rotation drive control system of a three-phase DC motor according to claim 19,

wherein when the third indicative voltage is between the second indicative voltage and the first indicative voltage, the third PWM signal is generated by comparing the negative phase triangular wave with the third indicative voltage, the second PWM signal is generated by comparing the positive phase triangular wave with the second indicative voltage, and the first PWM signal is generated by comparing the positive phase triangular wave with the first indicative voltage.

23. A rotation drive control system of a three-phase DC motor according to claim 22, further including a sample-and-hold signal generator,

wherein when the first indicative voltage is between the second indicative voltage and the third indicative voltage, the sample-and-hold signal generator generates a sample-and-hold signal to follow each of rising edges and falling edges of the first PWM signal, so as to provide a detection timing in connection with the current detection,

wherein when the second indicative voltage is between the first indicative voltage and the third indicative voltage, the sample-and-hold signal generator generates a sample-and-hold signal to follow each of rising edges and falling edges of the second PWM signal, so as to provide a detection timing in connection with the current detection,

wherein when the third indicative voltage is between the second indicative voltage and the first indicative voltage, the sample-and-hold signal generator generates a sample-and-hold signal to follow each of rising edges and falling edges of the third PWM signal, so as to provide a detection timing in connection with the current detection.

24. A rotation drive control system of a three-phase DC motor according to claim 19,

wherein the third indicative voltage is set as a first fixed signal so as to set the third PWM signal as a second fixed signal to a 100% or 0% duty.

25. A rotation drive control system of a three-phase DC motor according to claim 24, further including a sample-and-hold signal generator which generates a sample-and-hold signal to follow each of peak points of the positive phase triangular wave and the negative phase triangular wave so as to provide a detection timing in connection with the current detection.

26. A method of starting up a three-phase DC motor including three-phase coils and a rotor comprising:

generating a first current to flow through each of any two phases of the three-phase coils to detect a polarity of an induced voltage induced in a de-energized phase of the three-phase coils by a drive control unit driving and controlling the three-phase DC motor, thereby determining a direction of energization and corresponding two phase coils through which a second current flows to rotate the rotor;

based upon determining that any two detected levels of the induced voltages are larger than a predetermined level, determining the direction of energization and the corresponding two phase coils by using two detected polarities of the induced voltages in connection with said any two detected levels thereby rotating the rotor based upon the direction of energization and the corresponding two phase coils thereof are determined; and

driving the three-phase DC motor based upon a first determination in connection with the direction of the energization and the corresponding two phase coils,

wherein the rotor does not response by the first current, and

wherein a step of the determining includes;

based upon determining that said any two detected levels of the induced voltages are larger than the predetermined level, determining the direction of the energization and the corresponding two phase coils by inverting a detection result of a polarity of an induced voltage of the de-energized phase of the three-phase coils, the de-energized phase whose induced voltage is smaller than the predetermined level.