Rotor angle estimation for permanent magnet synchronous motor drive

• US 6,910,389 B2
• Filed: 11/12/2002
• Issued: 06/28/2005
• 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): Lefkowitz, Edward
• Assistant Examiner(s): DAVIS, OCTAVIA L
• Application Number:
  US10/294,201
• Publication Number:
  US 20030090262A1
• Time in Patent Office: 959 Days
• Field of Search: 324/772, 324/500, 324/545, 324/72.5, 318/245, 318/280, 318/432, 318/434, 318/461, 318/498, 318/254, 318/721, 702 32- 34, 702/54, 702/56, 738/621.93, 310/68.B, 310/90.5
• 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:

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, by calculating a first reactive power input value and a second reactive power input value;

determining a difference between said first and second reactive power input values; and

applying said differnece to the rotor angle estimated in step (b) to obtain a corrected rotor angle.

2. The method of claim 1, wherein step (a) includes the step of non-ideal integration of stator voltage and current values.

4. The method of claim 1, wherein step (c) includes the steps of:

calculating said first reactive power input value as 1.5*We*(C_Lq*I*I) and said second reactive power input value as 1.5*(Vq*id−

Vd*iq).

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

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. 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; and

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

wherein step (a) includes the step of non-ideal integration of stator voltage and current values; and

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

6. 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, by calculating a first reactive power input value and a second reactive power input value;

determining a difference between said first and second reactive power input values; and

applying said difference to the rotor angle estimated in step (b) to obtain a corrected rotor angle.

7. The method of claim 6, wherein said correcting step includes the steps of:

calculating said first reactive power input value as We*(C_Lq*I*I) and said second reactive power input value as (Vq*id−

Vd*iq).

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

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

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

c) a third circuit for correcting the estimated rotor angle on the basis of reactive power input to the motor, by calculating a first reactive power input value and a second reactive power input value;

determining a difference between said first and second reactive power input values; and

applying said difference to the rotor angle estimated in step (b) to obtain a corrected rotor angle.

9. The system of claim 8, wherein said first circuit carries out non-ideal integration of stator voltage and current values.

11. The system of claim 8, wherein said third circuit:

calculates said first reactive power input value as 1.5*WE*(C_Lq*I*I) and said second reactive power input value as 1.5*(Vq*id−

Vd*iq).

15. The system of claim 8, wherein said system is connected to a terminal of said motor for measuring said rotor magnetic flux.

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

19. The system of claim 8, wherein said system is connected to a terminal of the motor for measuring said stator voltage current values.

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

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

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

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

c) a third circuit for correcting the estimated rotor angle on the basis of reactive power input to the motor,

wherein said first circuit carries out non-ideal integration of stator voltage and current values; and

wherein said second circuit corrects phase errors caused by said non-ideal integration via a PLL circuit with phase compensation (F).

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

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

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

wherein said first circuit carries out non-ideal integration of stator voltage and current values; and

wherein said second circuit corrects phase errors caused by said non-ideal integration via a PLL circuit with phase compensation (F).

13. 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, by calculating a first reactive power input value and a second reactive power input value;

determining a difference between said first and second reactive power input values; and

applying said difference to the rotor angle estimated in step (b) to obtain a corrected rotor angle.

14. The system of claim 13, wherein said correcting circuit:

calculates said first reactive power input value as We*(C_Lq*I*I) and said second reactive power input value as (Vq*id−

Vd*iq).

17. The system of one of claims 8 and 13, wherein said system is connected to a terminal of the motor for measuring said reactive power input.

18. The system of claim 17, wherein said motor is a permanent magnet surface-mount motor.