Position control apparatus for motor

• US 20040085035A1
• Filed: 03/06/2003
• Published: 05/06/2004
• Est. Priority Date: 03/29/2002
• Status: Active Grant

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Iijima, Tomokuni, Suzuki, Kenichi, Tazawa, Toru, Yokouchi, Yasuyuki, Oyama, Ichiro, Narazaki, Kazushige
• Granted Patent: US 6,844,693 B2
• Time in Patent Office: Days
• US Class Current: 318/432
• CPC Class Codes: H02P 6/06 Arrangements for speed regulation of a single motor wherein the motor speed is measured and compared with a given physical value so as to adjust the motor speed
• CPC Class Codes: H02P 7/2805 whereby the speed is regulated by measuring the motor speed and comparing it with a given physical value

Abstract

An electric motor position control apparatus in accordance with the present invention has a plurality of sets of control parameters including at least the proportional gain of a position control section and the proportional gain of a speed control section beforehand, wherein set selection and the measurement of the response state of an electric motor to a position command at the time when the electric motor is controlled by using the control parameters of the selected set are carried out sequentially, one preferable set is selected depending on the measured response state, the control parameters of the selected set are set, and the control parameters are changed as a set.

Claims

1. An electric motor position control apparatus comprising:

a position/speed calculation section for calculating speed of an electric motor from a detection position of said electric motor or for calculating a position of said electric motor from a detection speed of said electric motor,

a position control section for making said detection position follow a position command value,

a speed control section for making said detection speed follow a speed command value depending on the output of said position control section;

an electric motor drive section for driving said electric motor on the basis of a torque command value depending on the output of said speed control section, and

a control parameter adjustment section having a plurality of sets of control parameters including at least the proportional gain of said position control section and the proportional gain of said speed control section, wherein set selection and the measurement operation of the response state of said electric motor to a position command at the time when said electric motor is controlled by using the control parameters of the selected set are carried out sequentially, and the control parameters of one set are set depending on the result of the measured response.

2. An electric motor position control apparatus in accordance with claim 1, wherein

said control parameter adjustment section is configured so that:

when set selection and the measurement operation of the response state of said electric motor by controlling said electric motor by using the control parameters of the selected set are carried out sequentially, among the detection of a vibration component having a predetermined frequency or more and included in the detection position or the-detection speed of said electric motor, the detection of a vibration component having a predetermined frequency or more and included in a torque command input to said electric motor drive section and the detection of the error between the position command value and the detection position after the end of the position command, the measurement operation including at least one vibration component detection is carried out sequentially from a set having a low proportional gain of said speed control section to a set having a higher proportional gain thereof; and

in the measured response result,

(1) condition (1) wherein the period in which the amplitude of said vibration component has first predetermined value or more is less than said first predetermined time, in the period from the start of a position command to the start of the next command;

(2) condition (2) wherein the period in which the amplitude of said vibration component has said first predetermined value or more is less than a second predetermined time shorter than said first predetermined time, in the period from the start of a position command to the start of the next command; and

(3) condition (3) wherein the number of times the error between the position command value and the detection position intersects a preset positioning tolerance is less than a predetermined first number of times, in the period from the end time of a position command to the start of the next command;

one of sets satisfying one or more of said three conditions, including at least the condition (1), is selected, and the control parameters of the selected set are set.

3. An electric motor position control apparatus in accordance with claim 1, wherein

said control parameter adjustment section is configured so that:

when set selection and the measurement operation of the response state of said electric motor by controlling said electric motor by using the control parameters of the selected set are carried out sequentially, among the detection of a vibration component having a predetermined frequency or more and included in the detection position or the detection speed of said electric motor, the detection of a vibration component having a predetermined frequency or more and included in a torque command input to said electric motor drive section and the detection of the error between the position command value and the detection position after the end of the position command, the measurement operation including at least one vibration component detection is carried out sequentially from a set having a low proportional gain of said speed control section to a set having a higher proportional gain thereof; and

in the response result measured until it is detected that the period in which the amplitude of said vibration component has a first predetermined value or more is a first predetermined time or more, in the period from the start of a position command to the start of the next command,

(1) condition (1) wherein the period in which the amplitude of said vibration component has said first predetermined value or more is less than said first predetermined time, in the period from the start of a position command to the start of the next command;

(2) condition (2) wherein the period in which the amplitude of said vibration components has said first predetermined value or more is less than a second predetermined time shorter than said first predetermined time, in the period from the start of a position command to the start of the next command; and

(3) condition (3) wherein the number of times the error between the position command value and the detection position intersects a preset positioning tolerance is less than a predetermined first number of times, in the period from the end time of a position command to the start of the next command;

one of sets satisfying one or more of said three conditions, including at least the condition (1), is selected, and the control parameters of the selected set are set.

4. An electric motor position control apparatus in accordance with claim 1, wherein

said control parameter adjustment section is configured so that:

when set selection and the measurement operation of the response state of said electric motor by controlling said electric motor by using the control parameters of the selected set are carried out sequentially, among the detection of a vibration component having a predetermined frequency or more and included in the detection position or the detection speed of said electric motor, the detection of a vibration component having a predetermined frequency or more and included in a torque command input to said electric motor drive section and the detection of the error between the position command value and the detection position after the end of the position command, the measurement operation including at least one vibration component detection is carried out sequentially; and

in the set selection,

(A) first selection;

in the case when it is detected that the period in which the amplitude of the vibration component has a first predetermined value or more is a first predetermined time or more, in the period from the start of a position command to the start of the next command, among the sets wherein the response states have already been measured and it is not detected that the time in which the amplitude of the vibration component has said first predetermined value or more is said first predetermined time or more, a set having the highest proportional gain of said speed control section is selected next;

or in the case when the proportional gain of said speed control section corresponding to said condition does not exist, a set having the proportional gain of said speed control section, the value of which is between the lowest proportional gain of said speed control section in all the sets and the proportional gain of said speed control section having been set at present, is selected next;

(B) second selection;

in the case when it is not detected that the period in which the amplitude of the vibration component has said first predetermined value or more is said first predetermined time or more, in the period from the start of a position command to the start of the next command, among the sets wherein the response states have already been measured and it is detected that the period in which the amplitude of the vibration component has said first predetermined value or more is said first predetermined time or more, a set having the lowest proportional gain of said speed control section is selected next;

or in the case when the proportional gain of said speed control section corresponding to said condition does not exist, a set having the proportional gain of said speed control section, the value of which is between the highest proportional gain of said speed control section in all the sets and the proportional gain of said speed control section having been set at present, is selected next;

the two selections are repeated;

in said selections, when no set is available as a set to be selected next, in the measured response result,

(1) condition (1) wherein the period in which the amplitude of said vibration component has said first predetermined value or more is less than said first predetermined time, in the period from the start of a position command to the start of the next command;

(2) condition (2) wherein the period in which the amplitude of said vibration component has said first predetermined value or more is less than a second predetermined time shorter than said first predetermined time, in the period from the start of a position command to the start of the next command; and

(3) condition (3) wherein the number of times the error between the position command value and the detection position intersects a preset positioning tolerance is less than a predetermined first number of times, in the period from the end time of a position command to the start of the next command;

one of sets satisfying one or more of said three conditions, including at least the condition (1), is selected, and the control parameters of the selected set are set.

5. An electric motor position control apparatus in accordance with any one of claims 2 to 4, wherein said control parameter adjustment section is configured to select first a start set designated externally.

6. An electric motor position control apparatus-in accordance with any one of claims 2 to 4, further comprising a load configuration pattern input section having a plurality of load configuration patterns related to a start set, one of said plurality of load configuration patterns being designated externally, wherein

said control parameter adjustment section is configured so as to first select the start set related to the load configuration pattern input from said load configuration pattern input section.

7. An electric motor position control apparatus in accordance with any one of claims 2 to 4, wherein

said control parameter adjustment section sequentially carries out set selection and the measurement operation of the response state of said electric motor to a position command at the time when said electric motor is controlled by using the control parameters of the selected set,

among sets satisfying one or more of said three conditions, including at least the condition (1), a set having the highest proportional gain of said speed control section is selected, and the control parameters of the selected set are set.

8. An electric motor position control apparatus in accordance with any one of claims 2 to 4, wherein said control parameter adjustment section is configured so that, when it is detected that the period in which the amplitude of a vibration component has said first predetermined value or more is said first predetermined time or more, in the period from the start of a position command to the start of the next command, the control parameter of a set, having the proportional gain of said speed control section lower than the proportional gain of the present speed control section, is set immediately, said electric motor is controlled a second predetermined number of times, and then the next set is selected.

9. An electric motor position control apparatus in accordance with any one of claims 1 to 4, wherein said control parameter adjustment section is configured so as to have a plurality of sets of control parameters including the proportional gain of said position control section and the proportional gain of said speed control section on the basis of at least one of said position command value, said speed command value, said detection position and said detection speed, wherein set selection and the measurement operation of the response state of an electric motor to a position command at the time when said electric motor is controlled by using the control parameters of the selected set are carried out sequentially, one set of control parameters is selected depending on the measured response state, and the control parameters of the selected set are set.

10. An electric motor position control apparatus in accordance with any one of claims 1 to 4, wherein said control parameter adjustment section has a plurality of sets of control parameters including at least the proportional gain of said speed control section, the proportional gain of said position control section at the time after the end of said position command and when the detection speed of said electric motor is larger than a second predetermined value and the proportional gain of said position control section at the time after the end of said position command and when the detection speed of said electric motor is not more than said second predetermined value.

11. An electric motor position control apparatus in accordance with any one of claims 1 to 4, wherein said control parameter adjustment section has a plurality of sets of control parameters including at least the proportional gain of said speed control section, the proportional gain of said position control section at the time after the end of said position command and when the detection speed of said electric motor is larger than a second predetermined value and the proportional gain of said position control section at the time after the end of said position command and when the detection speed of said electric motor is not more than said second predetermined value,

in the switching of the proportional gain of said position control section at the time after the end of said position command and when the detection speed of said electric motor is not more than said second predetermined value,

in the case when the proportional gain of said position control section at the time after the end of said position command and when the detection speed of said electric motor is larger than said second predetermined value is larger than the proportional gain of said position control section at the time after the end of said position command and when the detection speed of said electric motor is not more than said second predetermined value, the switching is done gradually over a predetermined time after the end of said position command and since when the detection speed of said electric motor is not more than said second predetermined value.

18. An electric motor position control apparatus in accordance with any one of claims 1 to 4, wherein said control parameter adjustment section has a function of setting the control parameters of the present set and controlling said electric motor a third predetermined number of times and then setting the control parameters of a set selected next, and

said control parameter adjustment section is configured so as to detect condition (2) and condition (3) of said three conditions only after control is carried out a fourth predetermined number of times smaller than said third predetermined number of times after the control parameters of the selected set are set.

19. An electric motor position control apparatus in accordance with any one of claims 11 to 16, wherein said control parameter adjustment section has a function of setting the control parameters of the present set and controlling said electric motor a third predetermined number of times and then setting the control parameters of a set selected next, and

said control parameter adjustment section is configured so as to detect condition (2) and condition (3) of said three conditions only after control is carried out a fourth predetermined number of times smaller than said third predetermined number of times after the control parameters of the selected set are set.

20. An electric motor position control apparatus in accordance with any one of claims 1 to 4, comprising:

a notch filter disposed in a position control system or a speed control system and having a variable notch center frequency, and

a notch frequency correction section for sequentially correcting the notch frequency of said notch filter to reduce frequency components having a predetermined frequency or more and included in said detection position or said detection speed or to reduce frequency components having a predetermined frequency or more and included in a torque command to be input to said electric motor drive section.

21. An electric motor position control apparatus in accordance with any one of claims 1 to 4, comprising:

a notch filter disposed in a position control system or a speed control system and having a variable notch center frequency,

a notch frequency correction section for sequentially correcting the notch frequency of said notch filter to reduce frequency components having a predetermined frequency or more and included in said detection position or said detection speed or to reduce frequency components having a predetermined frequency or more and included in a torque command to be input to said electric motor drive section, and

a notch frequency storage section that, when a selected set is changed, stores said set immediately before the change and the notch frequency immediately before the change so as to be related to each other, and that, when a newly selected set is the same as a set selected in the past, resets the notch frequency stored so as to be related to said set selected in the past as the notch frequency of said notch filter.

23. An electric motor position control apparatus in accordance with any one of claims 1 to 4, comprising:

a notch filter disposed in a position control system or a speed control system and having a variable notch frequency,

a notch frequency correction section for sequentially correcting the notch frequency of said notch filter to reduce frequency components having a predetermined frequency or more and included in said detection position or said detection speed or to reduce frequency components having a predetermined frequency or more and included in a torque command to be input to said electric motor drive section, and

a notch frequency storage section that, when a selected set is changed, stores the set immediately before the change and the notch frequency immediately before the change so as to be related to each other, and that, when a newly selected set is the same as a set selected in the past, resets the notch frequency stored so as to be related to said set selected in the past as the notch frequency of said notch filter, and then prohibits the change of the notch frequency of said notch filter in a fourth predetermined time.

25. An electric motor position control apparatus in accordance with any one of claims 1 to 4, wherein

said control parameter adjustment section is configured to detect a vibration component having a predetermined frequency or more and included in the detection position or the detection speed of said electric motor or to detect a frequency component having a predetermined frequency or more and included in a torque command to be input to said electric motor drive section.

27. An electric motor position control apparatus in accordance with any one of claims 1 to 4, wherein the period in which said position command satisfies predetermined conditions is a period excluding the period of a predetermined time from the time when the change of the acceleration of said position command has a predetermined value or more.

29. An electric motor position control apparatus in accordance with any one of claims 1 to 4, wherein the period in which said position command satisfies said predetermined conditions is:

(1) a period until a predetermined time elapses from the time when the time-related change of said position command was made from zero to nonzero, and

(2) a period excluding the period until the predetermined time elapses from the time when the time-related change of said position command was made from nonzero to zero.

31. An electric motor position control apparatus in accordance with any one of claims 1 to 4, wherein the period in which said position command satisfies said predetermined conditions is:

(1) a period in which the time-related change of said position command is nonzero, and

(2) a period excluding the period until the predetermined time elapses from the time when the time-related change of said position command was made from nonzero to zero.

12. An electric motor position control apparatus comprising:

a position/speed calculation section for calculating speed of an electric motor from a detection position of said electric motor or for calculating a position of said electric motor from a detection speed of said electric motor,

a position control section for making said detection position follow a position command value,

a speed control section for making said detection speed follow a speed command value depending on the output of said position control section;

an electric motor drive section for driving said electric motor on the basis of a torque command value depending on the output of said speed control section, and

a control parameter adjustment section having a plurality of sets of control parameters including at least the proportional gain of said position control section and the proportional gain of said speed control section, wherein

said control parameter adjustment section is configured so that;

when set selection and the measurement operation of the response state of said electric motor by controlling said electric motor by using the control parameters of the selected set are carried out sequentially, among the detection of a vibration component having a predetermined frequency or more and included in the detection position or the detection speed of said electric motor, the detection of a vibration component having a predetermined frequency or more and included in a torque command input to said electric motor drive section and the detection of the error between the position command value and the detection position after the end of the position command, the measurement operation including at least one vibration component detection is carried out sequentially; and

in the measured response result,

(1) condition (1) wherein the period in which the amplitude of said vibration component has said first predetermined value or more is less than said first predetermined time, in the period from the start of a position command to the start of the next command;

(2) condition (2) wherein the period in which the amplitude of said vibration component has said first predetermined value or more is less than a second predetermined time shorter than said first predetermined time, in the period from the start of a position command to the start of the next command; and

(3) condition (3) wherein the number of times the error between the position command value and the detection position intersects a preset positioning tolerance is less than a predetermined first number of times, in the period from the end time of a position command to the start of the next command;

one of sets satisfying one or more of said three conditions, including at least the condition (1), is selected;

when it is detected that the period in which the amplitude of said vibration component has said first predetermined value or more is said first predetermined time or more, in the period from the start of a position command to the start of the next command, while said electric motor is controlled a third predetermined number of times from the time when the control parameters of the selected set are set, among the sets satisfying one or more of said three conditions, including at least the condition (1) and excluding the present set, a set having the highest proportional gain of said speed control section is selected newly, and the control parameters of the newly selected set are set.

22. An electric motor position control apparatus in accordance with any one of claims 12 to 17, comprising:

a notch filter disposed in a position control system or a speed control system and having a variable notch center frequency,

a notch frequency correction section for sequentially correcting the notch frequency of said notch filter to reduce frequency components having a predetermined frequency or more and included in said detection position or said detection speed or to reduce frequency components having a predetermined frequency or more and included in a torque command to be input to said electric motor drive section, and

a notch frequency storage section that, when a selected set is changed, stores the set immediately before the change and the notch frequency immediately before the change so as to be related to each other, and that, when a newly selected set is the same as a set selected in the past, resets the notch frequency stored so as to be related to said set selected in the past as the notch frequency of said notch filter.

24. An electric motor position control apparatus in accordance with any one of claims 12 to 17, comprising:

a notch filter disposed in a position control system or a speed control system and having a variable notch frequency,

a notch frequency correction section for sequentially correcting the notch frequency of said notch filter to reduce frequency components having a predetermined frequency or more and included in said detection position or said detection speed or to reduce frequency components having a predetermined frequency or more and included in a torque command to be input to said electric motor drive section, and

a notch frequency storage section that, when a selected set is changed, stores the set immediately before the change and the notch frequency immediately before the change so as to be related to each other, and that, when a newly selected set is the same as a set selected in the past, resets the notch frequency stored so as to be related to said set selected in the past as the notch frequency of said notch filter, and then prohibits the change of the notch frequency of said notch filter in a fourth predetermined time.

26. An electric motor position control apparatus in accordance with any one of claims 12 to 17, wherein

said control parameter adjustment section is configured to detect a vibration component having a predetermined frequency or more and included in the detection position or the detection speed of said electric motor or to detect a frequency component having a predetermined frequency or more and included in a torque command to be input to said electric motor drive section.

28. An electric motor position control apparatus in accordance with any one of claims 12 to 17, wherein the period in which said position command satisfies predetermined conditions is a period excluding the period of a predetermined time from the time when the change of the acceleration of said position command has a predetermined value or more.

30. An electric motor position control apparatus in accordance with any one of claims 12 to 17, wherein the period in which said position command satisfies said predetermined conditions is:

(1) a period until a predetermined time elapses from the time when the time-related change of said position command was made from zero to nonzero, and

(2) a period excluding the period until the predetermined time elapses from the time when the time-related change of said position command was made from nonzero to zero.

32. An electric motor position control apparatus in accordance with any one of claims 12 to 17, wherein the period in which said position command satisfies said predetermined conditions is:

(1) a period in which the time-related change of said position command is nonzero, and

(2) a period excluding the period until the predetermined time elapses from the time when the time-related change of said position command was made from nonzero to zero.

13. An electric motor position control apparatus comprising:

a position/speed calculation section for calculating speed of an electric motor from a detection position of said electric motor or for calculating a position of said electric motor from a detection speed of said electric motor,

a position control section for making said detection position follow a position command value,

a speed control section for making said detection speed follow a speed command value depending on the output of said position control section;

an electric motor drive section for driving said electric motor on the basis of a torque command value depending on the output of said speed control section, and

a control parameter adjustment section having a plurality of sets of control parameters including at least the proportional gain of said position control section and the proportional gain of said speed control section, wherein

said control parameter adjustment section is configured so that;

when set selection and the measurement operation of the response state of said electric motor by controlling said electric motor by using the control parameters of the selected set are carried out sequentially, among the detection of a vibration component having a predetermined frequency or more and included in the detection position or the detection speed of said electric motor, the detection of a vibration component having a predetermined frequency or more and included in a torque command input to said electric motor drive section and the detection of the error between the position command value and the detection position after the end of the position command, the measurement operation including at least one vibration component detection is carried out sequentially; and

in the measured response result,

(1) condition (1) wherein the period in which the amplitude of said vibration component has said first predetermined value or more is less than the first predetermined time, in the period from the start of a position command to the start of the next command;

(2) condition (2) wherein the period in which the amplitude of said vibration component has said first predetermined value or more is less than a second predetermined time shorter than said first predetermined time, in the period from the start of a position command to the start of the next command; and

(3) condition (3) wherein the number of times the error between the position command value and the detection position intersects a preset positioning tolerance is less than a predetermined first number of times, in the period from the end time of a position command to the start of the next command;

one of sets satisfying one or more of said three conditions, including at least the condition (1), is selected, and the control parameters of the selected set are set,

next, at least the proportional gain of said speed control section among the control parameters having been set at present is fixed, and the remaining control parameters are changed, whereby the parameters other than the fixed parameter are set depending on the response state of said electric motor to the position command at the time when said electric motor is controlled.

14. An electric motor position control apparatus in accordance with claim 13, wherein

said control parameter adjustment section has a plurality of sets of control parameters including at least the proportional gain of said position control section, the proportional gain of said position control section at the time after the end of said position command and when the detection speed of said electric motor is larger than a second predetermined value and the proportional gain of said position control section at the time after the end of said position command and when the detection speed of said electric motor is not more than said second predetermined value, and

said control parameter adjustment section is configured so that:

when set selection and the measurement operation of the response state of said electric motor by controlling said electric motor by using the control parameters of the selected set are carried out sequentially, among the detection of a vibration component having a predetermined frequency or more and included in the detection position or the detection speed of said electric motor, the detection of a vibration component having a predetermined frequency or more and included in a torque command input to said electric motor drive section and the detection of the error between the position command value and the detection position after the end of the position command, the measurement operation including at least one vibration component detection is carried out sequentially;

in the measured response result,

(1) condition (1) wherein the period in which the amplitude of said vibration component has first predetermined value or more is less than said first predetermined time, in the period from the start of said position command to the start of the next command;

(2) condition (2) wherein the period in which the amplitude of said vibration component has said first predetermined value or more is less than a second predetermined time shorter than said first predetermined time, in the period from the start of said position command to the start of the next command; and

(3) condition (3) wherein the number of times the error between said position command value and said detection position intersects a preset positioning tolerance is less than a predetermined number of times, after the end time of said position command,

one of sets satisfying one or more of said three conditions, including at least the condition (1), is selected, and the control parameters of the selected set are set,

next, among the control parameters having been set at present, only the proportional gain of said position control section at the time after the end of said position command and when the detection speed of said electric motor is not more than said second predetermined value is changed in a predetermined range, and the response state at the time when said electric motor is controlled is measured;

in the measured response result, the proportional gain of said position control section satisfying condition (2) and condition (3) among said three conditions and making the time until the error between said detection position and said position command value enters a preset positioning tolerance after the end of said position command shortest is set.

15. An electric motor position control apparatus in accordance with claim 13, wherein

said control parameter adjustment section has a plurality of sets of control parameters including at least the proportional gain of said position control section, the proportional gain of said position control section at the time after the end of said position command and when the detection speed of said electric motor is larger than a predetermined value and the proportional gain of said position control section at the time after the end of said position command and when the detection speed of said electric motor is not more than a second predetermined value, and

said control parameter adjustment section is configured so that:

when set selection and the measurement operation of the response state of said electric motor by controlling said electric-motor by using the control parameters of the selected set are carried out sequentially, among the detection of a vibration component having a predetermined frequency or more and included in the detection position or the detection speed of said electric motor, the detection of a vibration component having a predetermined frequency or more and included in a torque command input to said electric motor drive section and the detection of the error between the position command value and the detection position after the end of the position command, the measurement operation including at least one vibration component detection is carried out sequentially;

in the measured response result,

(1) condition (1) wherein the period in which the amplitude of said vibration component has first predetermined value or more is less than said first predetermined time, in the period from the start of said position command to the start of the next command;

(2) condition (2) wherein the period in which the amplitude of said vibration component has said first predetermined value or more is less than a second predetermined time shorter than said first predetermined time, in the period from the start of said position command to the start of the next command; and

(3) condition (3) wherein the number of times the error between said position command value and said detection position intersects a preset positioning tolerance is less than a predetermined number of times, after the end time of said position command,

one of sets satisfying one or more of said three conditions, including at least the condition (1), is selected, and the control parameters of the selected set are set,

next, among the control parameters having been set at present, only the proportional gain of said position control section at the time after the end of said position command and when the detection speed of said electric motor is not more than said second predetermined value is changed in increasing order thereof in a predetermined range, and the response state at the time when said electric motor is controlled is measured,

at the time after the end of said position command and when the number of times the error between said detection position and said position command value intersects a preset positioning tolerance is not less than a predetermined number of times, the change of said proportional gain of said position control section is stopped,

at the time of stop, the proportional gain of said position control section satisfying condition (2) and condition (3) among said three conditions and making the time until the error between said detection position and said position command value enters a preset positioning tolerance after the end of said position command shortest is set.

16. An electric motor position control apparatus in accordance with claim 13, wherein

said control parameter adjustment section has a plurality of sets of control parameters including at least the proportional gain of said position control section, the proportional gain of said position control section at the time after the end of said position command and when the detection speed of said electric motor is larger than a second predetermined value and the proportional gain of said position control section at the time after the end of said position command and when the detection speed of said electric motor is not more than said second predetermined value, and

said control parameter adjustment section is configured so that:

when set selection and the measurement operation of the response state of said electric motor by controlling said electric motor by using the control parameters of the selected set are carried out sequentially, among the detection of a vibration component having a predetermined frequency or more and included in the detection position or the detection speed of said electric motor, the detection of a vibration component having a predetermined frequency or more and included in a torque command input to said electric motor drive section and the detection of the error between the position command value and the detection position after the end of the position command, the measurement operation including at least one vibration component detection is carried out sequentially;

in the measured response result,

(1) condition (1) wherein the period in which the amplitude of said vibration component has first predetermined value or more is less than said first predetermined time, in the period from the start of said position command to the start of the next command;

(2) condition (2) wherein the period in which the amplitude of said vibration component has said first predetermined value or more is less than a second predetermined time shorter than said first predetermined time, in the period from the start of said position command to the start of the next command; and

(3) condition (3) wherein the number of times the error between said position command value and said detection position intersects a preset positioning tolerance is less than a predetermined number of times, after the end time of said position command,

one of sets satisfying one or more of said three conditions, including at least the condition (1), is selected, and the control parameters of the selected set are set,

next, the proportional gain of said position control section at the time after the end of said position command and when the detection speed of said electric motor is not more than said second predetermined value and the predetermined value-of said detection speed for determining the proportional gain of said position control section are used as variables and changed in respectively different predetermined ranges, and the response state at the time when said electric motor is controlled is measured;

in the measured response result, the proportional gain of said position control section satisfying condition (2) and condition (3) among said three conditions and making the time until the error between said detection position and said position command value enters a preset positioning tolerance after the end of said position command shortest and the predetermined value of said detection speed for determining the proportional gain of said position control section are set.

17. An electric motor position control apparatus comprising:

a position/speed calculation section for calculating speed of an electric motor from a detection position of said electric motor or for calculating a position of said electric motor from a detection speed of said electric motor,

a position control section for making said detection position follow a position command value,

a speed control section for making said detection speed follow a speed command value depending on the output of said position control section;

an electric motor drive section for driving said electric motor on the basis of a torque command value depending on the output of said speed control section, and

a control parameter adjustment section wherein a target value of a time until the error between said detection position and said position command value enters a preset positioning tolerance after the end of said position command is set externally, wherein

said control parameter adjustment section is configured so that, in set selection and the measurement operation of the response state of said electric motor by using the control parameters of the selected set, when the time until the error between said detection position and said position command value enters said positioning tolerance after the end of said position command becomes not more than said target value having been set externally, the set selection is stopped, and the control parameters at that time are set.

33. An electric motor position control apparatus comprising:

a position/speed calculation section for calculating the speed of an electric motor from the detection position of said electric motor or for calculating the position of said electric motor from the detection speed of said electric motor,

a position control section for making said detection position follow a position command value,

a speed control section for making said detection speed follow a speed command value depending on the output of said position control section;

an electric motor drive section for driving said electric motor on the basis of a torque command value depending on the output of said speed control section,

an inertia estimation section for estimating the total inertia of said electric motor and a load driven by said electric motor on the basis of the acceleration calculated from said detection speed and said torque command value,

an inertia estimation temporary-stop judgment section for stopping the inertia estimation/calculation of said inertia estimation section for a predetermined time since when it is detected that the amplitude of a vibration component having a predetermined frequency or more and included in the detection position or the detection speed of said electric motor or the amplitude of a vibration component having a predetermined frequency or more and included in the torque command to be input to the electric motor drive section has a predetermined value or more, and

a control parameter adjustment section having a plurality of sets of control parameters including at least the proportional gain of said position control section and the proportional gain of said speed control section, wherein a set is selected and the response state of said electric motor to a position command at the time when said electric motor is controlled by using the control parameters of the selected set, and the control parameters of one set are set depending on this response state.