Apparatus and method for motor control using table

• US 20060192510A1
• Filed: 02/10/2006
• Published: 08/31/2006
• Est. Priority Date: 02/25/2005
• Status: Active Grant

• Current Assignee: Mitsubishi Heavy Industries, Ltd.
• Original Assignee: Mitsubishi Heavy Industries, Ltd.
• Inventors: Okazaki, Yoshimi, Okuda, Keisuke
• Granted Patent: US 7,443,127 B2
• Time in Patent Office: Days
• US Class Current: 318/139
• CPC Class Codes: B60L 15/025 using field orientation; Vector control; Direct Torque Control [DTC]
• CPC Class Codes: B60L 15/2045 for optimising the use of energy
• CPC Class Codes: B60L 2220/12 Induction machines
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility

Abstract

In an apparatus of controlling a motor in a battery vehicle, a current command generation section has a table, and generates an exciting command current and a torque command current by referring to the table based on a torque command. A converting section generates 3-phase command voltages from the exciting command current and the torque command current. A motor driving section drives a motor in response to the 3-phase command voltages.

Claims

1. An apparatus of controlling a motor in a battery vehicle, comprising:

a current command generation section having a table, and configured to generate an exciting command current and a torque command current by referring to said table based on a torque command;

a converting section configured to generate 3-phase command voltages from said exciting command current and said torque command current; and

a motor driving section configured to drive a motor in response to said 3-phase command voltages.

2. The apparatus according to claim 1, wherein said current command generation section generates said exciting command current and said torque command current by referring to said table based on a rotation frequency command for said motor in addition to said torque command.

3. The apparatus according to claim 2, wherein said table stores a relation of said exciting command current and said rotation frequency command with respect to said torque command and a relation of said torque command current and said rotation frequency command with respect to said torque command.

4. The apparatus according to claim 1, wherein said converting section comprises:

a q-axis controller configured to generate a q-axis command voltage based on said torque command current;

a d-axis controller configured to generate a d-axis command voltage based on said exciting command current; and

a first converter configured to convert said q-axis command voltage and said d-axis command voltage into said 3-phase command voltages.

5. The apparatus according to claim 4, wherein said motor driving section further comprises:

a current sensor configured to sense currents of at least 2 phases supplied to said motor,

said apparatus further comprises;

a second converter configured to generate an actual torque current and an actual exciting current from said sensed currents to output said actual torque current to said q-axis controller and said actual exciting current to said d-axis controller,

said q-axis controller generates said q-axis command voltage based on said actual torque current in addition to said torque command current, and

said d-axis controller generates said d-axis command voltage based on said actual exciting current in addition to said exciting command current.

6. The apparatus according to claim 4, wherein said motor has an encoder configured to measure a rotation frequency of said motor,

said apparatus further comprises:

a phase calculation section configured to calculate a phase from said exciting command current, said torque command current, the measured rotation frequency by said encoder, and

said first converter converts said q-axis command voltage and said d-axis command voltage into said 3-phase command voltages based on said phase.

7. The apparatus according to claim 6, wherein said motor driving section further comprises:

a current sensor configured to sense currents of at least 2 phases supplied to said motor,

said apparatus further comprises;

a second converter configured to generate an actual torque current and an actual exciting current from said sensed currents on said phase.

8. The apparatus according to claim 3, wherein said exciting command current and said torque command current are previously determined from said rotation frequency command and said torque command by using an actual motor.

9. A method of controlling a motor in a battery vehicle, comprising:

referring to a table based on a torque command to generate an exciting command current and a torque command current;

generating 3-phase command voltages from said exciting command current and said torque command current; and

driving a motor in response to said 3-phase command voltages.

10. The method according to claim 9, wherein said referring comprises:

referring to said table based on a rotation frequency command for said motor in addition to said torque command section to generate said exciting command current and said torque command current.

11. The method according to claim 10, wherein said table stores a relation of said exciting command current and said rotation frequency command with respect to said torque command and a relation of said torque command current and said rotation frequency command with respect to said torque command.

12. The method according to claim 9, wherein said generating 3-phase command voltages comprises:

generating a q-axis command voltage based on said torque command current;

generating a d-axis command voltage based on said exciting command current; and

converting said q-axis command voltage and said d-axis command voltage into said 3-phase command voltages.

13. The method according to claim 12, further comprising:

sensing currents of at least 2 phases supplied to said motor; and

generating an actual torque current and an actual exciting current from said sensed currents,

said generating a q-axis command voltage comprises;

generating said q-axis command voltage based on said actual torque current in addition to said torque command current, and

said generating a d-axis command voltage comprises;

generating said d-axis command voltage based on said actual exciting current in addition to said exciting command current.

14. The method according to claim 11, further comprising:

measuring a rotation frequency of said motor; and

calculating a phase from said exciting command current, said torque command current, the measured rotation frequency,

wherein said converting into said 3-phase command voltages comprises;

converting said q-axis command voltage and said d-axis command voltage into said 3-phase command voltages based on said phase.

15. The method according to claim 14, further comprising:

sensing currents of at least 2 phases supplied to said motor; and

generating an actual torque current and an actual exciting current from said sensed currents based on said phase.

16. The method according to claim 11, wherein said exciting command current and said torque command current are previously determined from said rotation frequency command and said torque command by using an actual motor.

17. The method according to claim 9, further comprising:

a providing a table in advance,

wherein said providing comprises;

setting a plurality of a rotation frequency commands;

setting a plurality of torque commands to said plurality of rotation frequency commands;

previously measuring a torque current and an exciting current to each of said plurality of torque commands; and

generating said table based on said torque currents and said exciting current for said plurality of torque commands and said plurality of rotation frequency commands.