Rotor angle estimation for permanent magnet synchronous motor drive

• US 7,299,708 B2
• Filed: 10/18/2004
• Issued: 11/27/2007
• Est. Priority Date: 11/12/2001
• Status: Expired due to Term

• Current Assignee: Infineon Technologies Americas Corp. (Infineon Technologies AG)
• Original Assignee: International Rectifier Corporation (Infineon Technologies AG)
• Inventors: Ho, Eddy Ying Yin
• Primary Examiner(s): Cygan; Michael
• Assistant Examiner(s): DAVIS, OCTAVIA L
• Application Number:
  US10/967,596
• Publication Number:
  US 20050081647A1
• Time in Patent Office: 1,135 Days
• Field of Search: 738/621.93, 318/700, 318/254, 318/439, 324/207.12
• US Class Current: 73/862.193
• CPC Class Codes: H02P 6/085 in a bridge configuration
• CPC Class Codes: H02P 6/18 without separate position detecting elements

Abstract

A method of determining a rotor angle in a drive control for a motor, comprising the steps of (a) determining a rotor magnetic flux in the motor; (b) estimating the rotor angle on the basis of the rotor magnetic flux; and (c) correcting the estimated rotor angle on the basis of reactive power input to the motor. Step (a) may include the step of non-ideal integration of stator voltage and current values.

Step (b) may include the step of correcting phase errors caused by said non-ideal integration via a PLL circuit with phase compensation (F). Step (c) may include the steps of (1) calculating a first reactive power input value as 1.5*We*(C_Lq*I*I) and a second reactive power input value as 1.5*(Vq*id−Vd*iq); (2) determining a difference between said first and second reactive power input values; and (3) applying said difference to the rotor angle estimated in step (b) to obtain a corrected rotor angle.

Claims

1. A method of determining a rotor angle in a drive control for a motor, comprising the steps of:

estimating a rotor angle; and

correcting the estimated rotor angle on the basis of reactive power input to the motor.

2. The method of claim 1, further comprising the steps of:

a) determining a rotor magnetic flux in the motor; and

b) estimating the rotor angle on the basis of the rotor magnetic flux.

3. The method of claim 2, wherein step (a) includes the step of non-ideal integration of stator voltage and current values.

4. The method of claim 3, wherein step (b) includes the step of correcting phase errors caused by said non-ideal integration via a PLL circuit with phase compensation (F).

5. The method of claim 3, wherein step (a) includes the step of non-ideal integration of motor back emf based on stator resistance, inductance, voltage and current values.

6. The method of claim 2, wherein said motor is an interior permanent magnet motor.

7. The method of claim 2, wherein said rotor magnetic flux is determined without a filter function.

8. The method of claim 1, wherein said motor is an interior permanent magnet motor.

9. The system of claim 1, wherein said reactive power input to the motor is determined on the basis of motor frequency.

10. A system for determining a rotor angle in a drive control for a motor, comprising:

a circuit for estimating a rotor angle; and

a circuit for correcting the estimated rotor angle on the basis of reactive power input to the motor.

11. The system of claim 10, further comprising:

a) a first circuit for determining a rotor magnetic flux in the motor; and

b) a second circuit for estimating the rotor angle on the basis of the rotor magnetic flux.

12. The system of claim 11, wherein said first circuit carries out non-ideal integration of stator voltage and current values.

13. The system of claim 12, wherein said second circuit corrects phase errors caused by said non-ideal integration via a PLL circuit with phase compensation (F).

14. The system of claim 12, wherein said first circuit carries out non-ideal integration of motor back emf based on stator resistance, inductance, voltage and current values.

15. The system of claim 11, wherein said system is connected to a terminal of the motor for measuring said reactive power input.

16. The system of claim 15, wherein said motor is a permanent magnet surface-mount motor.

17. The system of claim 11, wherein said motor is an interior permanent magnet motor.

18. The system of claim 11, wherein said rotor magnetic flux is determined without a filter function.

19. The system of claim 10, wherein said system is connected to a terminal of said motor for measuring said rotor magnetic flux.

20. The system of claim 19, wherein said motor is a permanent magnet surface-mount motor.

21. The system of claim 10, wherein said system is connected to a terminal of the motor for measuring said stator voltage current values.

22. The system of claim 21, wherein said motor is a permanent magnet surface-mount motor.

23. The system of claim 10, wherein said system is connected to a terminal of the motor for measuring said reactive power input.

24. The system of claim 10, wherein said motor is an interior permanent magnet motor.

25. The system of claim 10, wherein said reactive power input to the motor is determined on the basis of motor frequency.