Motor controller

Patent metadata

Field	Value
Publication number	US-9369080-B2
Application number	US-201314422471-A
Country	US
Kind code	B2
Filing date	Dec 3, 2013
Priority date	Dec 6, 2012
Publication date	Jun 14, 2016
Grant date	Jun 14, 2016

Abstract

A motor controller of a switched reluctance motor includes an inverter, a torque and flux calculator configured to estimate or measure torque and flux generated in the switched reluctance motor as calculated torque flux, based on an output from the inverter and a rotor angle of the switched reluctance motor, a switching pattern selector configured to input a signal to the inverter to select one of a plurality of switching patterns based on comparison results of a reference torque and the calculated torque and a reference flux and the calculated flux, and a flux phase angle, and a reference flux calculator configured to compare a highest phase flux out of three phase fluxes obtained by the torque and flux calculator with a flux limit and to reduce the reference flux when the maximum phase flux is higher than the flux limit.

First claim

What is claimed is:

1. A motor controller configured to control a switched reluctance motor comprising:
an inverter connected to the switched reluctance motor;
a torque and flux calculator configured to estimate or measure torque and flux generated in the switched reluctance motor as calculated torque and calculated flux, based on an output from the inverter and a rotor angle of the switched reluctance motor;
a switching pattern selector configured to input a signal to the inverter to select one of a plurality of switching patterns based on a comparison result of a reference torque and the calculated torque, a comparison result of a reference flux and the calculated flux, and a flux phase angle; and
a reference flux calculator configured to compare a highest phase flux out of three phase fluxes obtained by the torque and flux calculator with a flux limit and reduce the reference flux when the highest phase flux is higher than the flux limit.

2. The motor controller according to claim 1 , wherein the reference flux calculator is configured to change the flux limit based on at least one of the reference torque and a rotating speed.

3. The motor controller according to claim 2 , wherein the reference flux calculator is configured to compare a highest phase current out of three phase currents outputted from the inverter with a current limit and to reduce the reference flux when the highest phase current is higher than the flux limit.

4. The motor controller according to claim 3 , wherein the inverter is a three-phase bridge inverter including six switching elements.

5. The motor controller according to claim 4 , wherein the reference flux calculator is configured to obtain the reference flux by subtracting a value calculated using a comparison result from a predetermined initial reference flux.

6. The motor controller according to claim 3 , wherein the reference flux calculator is configured to obtain the reference flux by subtracting a value calculated using a comparison result from a predetermined initial reference flux.

7. The motor controller according to claim 2 , wherein the inverter is a three-phase bridge inverter including six switching elements.

8. The motor controller according to claim 7 , wherein the reference flux calculator is configured to obtain the reference flux by subtracting a value calculated using a comparison result from a predetermined initial reference flux.

9. The motor controller according to claim 2 , wherein the reference flux calculator is configured to obtain the reference flux by subtracting a value calculated using a comparison result from a predetermined initial reference flux.

10. The motor controller according to claim 1 , wherein the reference flux calculator is configured to compare a highest phase current out of three phase currents outputted from the inverter with a current limit and to reduce the reference flux when the highest phase current is higher than the flux limit.

11. The motor controller according to claim 10 , wherein the inverter is a three-phase bridge inverter including six switching elements.

12. The motor controller according to claim 11 , wherein the reference flux calculator is configured to obtain the reference flux by subtracting a value calculated using a comparison result from a predetermined initial reference flux.

13. The motor controller according to claim 10 , wherein the reference flux calculator is configured to obtain the reference flux by subtracting a value calculated using a comparison result from a predetermined initial reference flux.

14. The motor controller according to claim 1 , wherein the inverter is a three-phase bridge inverter including six switching elements.

15. The motor controller according to claim 14 , wherein the reference flux calculator is configured to obtain the reference flux by subtracting a value calculated using a comparison result from a predetermined initial reference flux.

16. The motor controller according to claim 1 , wherein the reference flux calculator is configured to obtain the reference flux by subtracting a value calculated using a comparison result from a predetermined initial reference flux.

17. A motor controller configured to control a switched reluctance motor comprising:
an inverter connected to the switched reluctance motor;
a torque and flux calculator configured to estimate or measure a torque and a flux generated in the switched reluctance motor as calculated torque and calculated flux, based on an output from the inverter and a rotor angle of the switched reluctance motor;
a switching pattern selector configured to input a signal to the inverter to select one of a plurality of switching patterns based on a comparison result of a reference torque and the calculated torque, a comparison result of a reference flux and the calculated flux, and a flux phase angle; and
a reference flux calculator configured to compare a highest phase current out of three phase currents outputted from the inverter with a current limit and reduce the reference flux when the highest phase current is higher than the current limit.

18. The motor controller according to claim 17 , wherein the reference flux calculator is configured to change the current limit based on at least one of the reference torque and a rotating speed.

19. The motor controller according to claim 18 , wherein the reference flux calculator is configured to obtain the reference flux by subtracting a value calculated using a comparison result from a predetermined initial reference flux.

20. The motor controller according to claim 17 , wherein the inverter is a three-phase bridge inverter including six switching elements.

21. The motor controller according to claim 20 , wherein the reference flux calculator is configured to obtain the reference flux by subtracting a value calculated using a comparison result from a predetermined initial reference flux.

22. The motor controller according to claim 17 , wherein the reference flux calculator is configured to obtain the reference flux by subtracting a value calculated using a comparison result from a predetermined initial reference flux.

Assignees

• Nidec Corp

Inventors

• Ahmad Ghaderi

Classifications

• H02P31/00

  Arrangements for regulating or controlling electric motors not provided for in groups H02P1/00 - H02P5/00, H02P7/00 or H02P21/00 - H02P29/00 · CPC title

• H02P23/14 Primary

  Estimation or adaptation of motor parameters, e.g. rotor time constant, flux, speed, current or voltage · CPC title

• H02P25/088

  Electricity · mapped topic

• H02P25/098 Primary

  Arrangements for reducing torque ripple · CPC title