Motor control device and motor control method

Abstract

To realize shortening of auto-tuning.SOLUTION: By a servo amplifier 100 which adjusts a gain of a motor 300, an amplitude and an oscillation period of an oscillation component contained in a torque command value are acquired. If the amplitude and the oscillation period satisfy certain conditions, it is determined that setting of notch filters 141 and / or 142 is necessary, and then a notch frequency of the notch filters 141 and / or 142 is set to the period of the oscillation component immediately before the determination. This eliminates the necessity of extraction of oscillation by Fourier series expansion and acquisition of a data amount required for frequency analysis, so that processing of auto-tuning can be shortened.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a motor control device having an autotuning function and a motor control method. [Background technology]

[0002] When a servo motor is installed in a target device such as a robot or a machine tool, the gain of the servo amplifier needs to be adjusted according to the load inertia. Such servo amplifier gain adjustment is generally performed by a motor control device with an auto-tuning function.

[0003] In auto-tuning, multiple test operations are performed while changing tuning parameters, and the parameters to be set next are determined based on the results of each test operation. In addition, in auto-tuning, settings to suppress vibration of the motor are also performed.

[0004] As an example of a method for suppressing vibrations in such motors, Patent Document 1 proposes a motor control device that includes a rotation control means for controlling the rotation of the motor, an acceleration sensor as a vibration detection means for detecting vibrations of the motor during rotation, a specific frequency component extraction means for extracting vibration components of a specific frequency from the vibrations detected by the acceleration sensor, a vibration component decomposition means for decomposing the vibrations of the specific frequency into a main vibration component of the specific frequency and a pulsating vibration component superimposed on the main vibration component, and a repetitive control means for generating a compensation signal that simultaneously suppresses all of the main vibration components and pulsating vibration components and repeatedly inputting this compensation signal to the rotation control means. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2012-080614 A Summary of the Invention [Problem to be solved by the invention]

[0006] In the motor control device of the above-mentioned Patent Document 1, a compensation signal is obtained by decomposing vibrations of a specific frequency into a main vibration component and a pulsating vibration component, both of which have constant amplitude, so it is believed that motor vibrations can be efficiently suppressed.

[0007] However, in this motor control device, when the specific frequency component extraction means extracts the vibration component of the specific frequency from the vibration detected by the acceleration sensor, only the vibration of the specific frequency is extracted by Fourier series expansion.

[0008] In this way, when vibration extraction is performed using Fourier series expansion, not only does it take time to perform the frequency analysis process, but it also takes time to acquire the amount of data required for the frequency analysis, which is an obstacle to shortening the auto-tuning process.

[0009] For these reasons, there is a need for the development of a motor control device that can shorten the time required for auto-tuning processing.

[0010] The present invention has been made in view of the above circumstances, and has an object to provide a motor control device and a motor control method that can solve the above problems. [Means for solving the problem]

[0011] A motor control device according to the present invention includes a servo amplifier that adjusts a gain of a motor, and a notch filter, A peak of the torque command value is recognized from a characteristic of the torque command value over time, an amplitude of a vibration component is recognized from a peak-to-peak value in the characteristic, and a vibration period of the vibration component is recognized from a time between the peaks, The amplitude and The above If the vibration period satisfies a certain condition, it is determined that the notch filter needs to be set, and the notch frequency of the notch filter is set to the period of the vibration component immediately before the determination. Frequency corresponding to The feature is that it is set to. The motor control method of the present invention includes the steps of: A peak of the torque command value is recognized from a characteristic of the torque command value over time, an amplitude of a vibration component is recognized from a peak-to-peak value in the characteristic, and a vibration period of the vibration component is recognized from a time between the peaks, The amplitude and The aboveIf the vibration period satisfies a certain condition, it is determined that a notch filter needs to be set, and the notch frequency of the notch filter is set to the period of the vibration component immediately before the determination. Frequency corresponding to The feature is that it is set to. In the motor control device and the motor control method of the present invention, a servo amplifier that adjusts the gain of the motor is used to: A peak of the torque command value is recognized from a characteristic of the torque command value over time, an amplitude of a vibration component is recognized from a peak-to-peak value in the characteristic, and a vibration period of the vibration component is recognized from a time between the peaks, The amplitude and The above If the vibration period satisfies a certain condition, it is determined that a notch filter needs to be set, and the notch frequency of the notch filter is set to the period of the vibration component immediately before the determination. Frequency corresponding to Set to. Effect of the Invention

[0012] According to the motor control device and motor control method of the present invention, it is not necessary to extract vibrations through Fourier series expansion, and it is not necessary to acquire the amount of data required for frequency analysis, so that it is possible to shorten the auto-tuning process. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a diagram for explaining an embodiment of a motor control device of the present invention. [Figure 2A] FIG. 2A is a diagram for explaining acquisition of the amplitude and vibration frequency of a vibration component by the servo amplifier of FIG. 1, and is a diagram showing, for example, a vibration component included in a torque command value included in an adjustment command from a torque adjustment unit. [Figure 2B] FIG. 2B is a diagram for explaining acquisition of the amplitude and vibration frequency of the vibration component by the servo amplifier of FIG. 1, showing an example of a case where erroneous detection of the amplitude and vibration period of the vibration component occurs. [Diagram 3] FIG. 3 is a diagram for explaining the resetting of the torque notch when it is determined that the resetting is necessary after the torque notch is set by the servo amplifier in FIG. [Figure 4] FIG. 4 is a flowchart for explaining auto-tuning by the servo amplifier of FIG. [Diagram 5]FIG. 5 is a flowchart for explaining a vibration level analysis process performed by the servo amplifier of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] An embodiment of a motor control device of the present invention will be described below with reference to Figures 1 to 5. Note that when performing auto-tuning, the motor control device M described below needs to adjust the gain of the servo amplifier 100 in accordance with the load inertia, but for convenience of explanation, illustration and explanation of the load inertia will be omitted.

[0015] The motor control device M includes a servo amplifier 100 having an auto-tuning function. The servo amplifier 100 acquires, for example, the amplitude and vibration period of a vibration component included in a torque command value of an adjustment command from a torque adjustment unit 140. The servo amplifier 100 also automatically determines whether or not a torque notch and / or 142 described below is set based on the amplitude and duration of the vibration component (short time when the amplitude is high, long time when the amplitude is low). When the servo amplifier 100 determines that it is necessary to set notch filters 141 and / or 142 described below, it sets the notch frequency of the notch filters 141 and / or 142 to the period of the vibration component immediately before the determination. Note that reference numeral 300 denotes a motor, reference numeral 150 denotes a subtractor, and reference numeral 160 denotes an adder-subtractor.

[0016] The servo amplifier 100 includes a position adjustment unit 110 , a feedforward control unit 120 , a feedback control unit 130 , a torque adjustment unit 140 , and a current control unit 170 .

[0017] The position adjustment unit 110 outputs a position command according to a gain setting to the feedforward control unit 120 and the subtractor 150 based on a command indicating a target value including command values ​​for position, speed, and torque from a controller (not shown).

[0018] Based on the position command from the position adjustment unit 110, the feedforward control unit 120 outputs to the adder / subtractor 160 a feedforward command (FF command) including a speed command and a torque command for controlling the speed and torque.

[0019] The feedback control unit 130 outputs a feedback command (FB command) to the adder-subtractor 160 based on the feedback signal, so as to make the deviation from the subtractor 150 zero.

[0020] The torque adjustment unit 140 has a plurality of notch filters 141 and 142. The torque adjustment unit 140 outputs an adjustment command to the current control unit 170, the adjustment command being attenuated by the notch filters 141 and / or 142 in response to vibration contained in the torque command of the control command from the adder / subtractor 160.

[0021] The vibration included in the torque command is generated by the oscillation of the motor 300. The number of notch filters 141 and 142 is not limited to two as shown in the figure, and three or more may be provided. As the notch filters 141 and 142, an adaptive filter capable of self-adapting a transfer function according to an optimization algorithm may be used. Details regarding the setting of the notch filters 141 and 142 will be described later.

[0022] Subtractor 150 subtracts a position command according to a gain setting from position adjustment unit 110 from the position and velocity signals of the feedback signal, and outputs a deviation. Adder-subtractor 160 subtracts a feedforward command from a feedback command, and outputs a control command for making the deviation from subtractor 150 zero.

[0023] The current control unit 170 controls the drive current of the motor 300 so that the torque indicated by the adjustment command from the torque adjustment unit 140 is generated.

[0024] In the motor control device configured as above, when a command is output from a controller (not shown), the motor 300 starts driving based on a feedforward command (FF command) from the feedforward control unit 120.

[0025] When a feedback signal detected by an encoder (not shown) is output as motor 300 is driven, a control command for making the deviation from subtractor 150 zero is output from adder-subtractor 160 in response to a feedback command (FB command) from feedback control unit 130. Then, current control unit 170 controls the drive current of motor 300 so as to generate a torque indicated by the adjustment command from torque adjustment unit 140 with vibration damped.

[0026] Next, with reference to Fig. 2, the acquisition of the amplitude and vibration period of the vibration component by the servo amplifier 100 will be described. Note that conditions 1 to 4 described below are merely examples. In Fig. 2, the horizontal axis indicates time (ms) and the vertical axis indicates the torque command value during operation. Also, the torque command value of 1000 [0.1%] indicates the rated torque.

[0027] 2A shows, for example, the vibration components included in the torque command value included in the adjustment command from the torque adjustment unit 140. The vibration components included in the torque command value may be included in the output of the current controller 170. In FIG. 2A, a shows a threshold value for implementing a flow for searching for minimum values ​​P2 and P4 of the vibration components, and b shows a threshold value for implementing a flow for searching for maximum values ​​P1 and P3 of the vibration components. The threshold values ​​a and b are not limited to the positions shown in the figure, and can be set and changed arbitrarily. Furthermore, the vibration periods S1 and S2 show the difference times between the maximum values ​​P1 and P3 and between the minimum values ​​P2 and P4 of adjacent vibration components.

[0028] The servo amplifier 100 constantly monitors the torque command value included in the adjustment command from the torque adjustment unit 140 for each position / speed control period, and acquires the amplitude and vibration period of the vibration component of the torque command value. Furthermore, when acquiring the amplitude and vibration periods S1, S2 of the vibration components, the servo amplifier 100 acquires the polarity switching thresholds a and b. The thresholds a and b can be set according to the acquisition level (or detection level) for acquiring the amplitude and vibration periods S1, S2 of the vibration components.

[0029] When the maximum value P1 and the minimum value P2 of the vibration component exceed the thresholds a and b, the servo amplifier 100 calculates Peak to Peak (PP), which is the difference (amplitude) between the maximum value P1 and the minimum value P2 of the vibration component. In addition, the servo amplifier 100 calculates the vibration periods S1 and S2 between the maximum values ​​P1 and P3 of the vibration components of adjacent periods and between the minimum values ​​P2 and P4 of the vibration components of adjacent periods.

[0030] The servo amplifier 100 calculates Peak to Peak (PP), which is the difference (amplitude) between the maximum value P1 and the minimum value P2 of the vibration component, and the vibration periods S1 and S2, and then determines that it is necessary to set the notch filters 141 and / or 142 if the following conditions 1 and 2 are met. Condition 1: Peak to Peak (PP) exceeds 30% of the rated value and the vibration periods S1 and S2 exceed 10 ms. Condition 2: Peak to Peak (PP) exceeds 10% of the rated value and the vibration periods S1 and S2 exceed 50 ms.

[0031] In addition, even if the Peak to Peak (PP) is small, if the oscillation continues, people may feel uncomfortable. In this case, the servo amplifier 100 determines that the setting of the notch filters 141 and / or 142 is necessary if the following conditions 3 and 4 are satisfied. Condition 3: Peak to Peak (PP) exceeds 25% of the rated value and the vibration periods S1 and S2 exceed 10 ms. Condition 4: Peak to Peak (PP) exceeds 10% of the rated value and the vibration periods S1 and S2 exceed 100 ms.

[0032] When the servo amplifier 100 determines that the setting of the notch filters 141 and / or 142 is necessary, it sets the notch frequency of the notch filters 141 and / or 142 to the period of the vibration component immediately before the determination.

[0033] 2B is a diagram showing an example of a case where erroneous detection of the amplitude and vibration periods S1 and S2 of the vibration component occurs. As shown in the figure, the vibration component of the torque command value may rise from the minimum value P2 of the vibration component, and immediately after exceeding threshold value b, the vibration component of the torque command value may fall below threshold value b. This is considered to be due to a delay in tracking the gain adjustment of the control parameters by servo amplifier 100 when motor 300 is started.

[0034] In this case, the servo amplifier 100 determines that it is not necessary to set the notch filters 141 and / or 142, for example, when PeaktoPeak (PP), which is the difference (amplitude) between the minimum value P2 and the maximum value P5 of the vibration period S2, is significantly different from PeaktoPeak (PP), which is the difference (amplitude) between the maximum value P5 and the minimum value P6 of the vibration period S2.

[0035] 3 is a diagram for explaining the resetting of the torque notches 141 and / or 142 when it is determined that resetting is necessary after the servo amplifier 100 sets the notch filter 141. In FIG. 3, the horizontal axis indicates time (ms), and the vertical axis indicates the torque command value during operation and the measured frequency after the notch filters 141 and / or 142 are set.

[0036] Even if the servo amplifier 100 sets the notch frequency f1 of the notch filter 141 to the period of the vibration component immediately before the judgment (immediately before the time when it is judged that the setting of the notch filters 141 and / or 142 is necessary due to the occurrence of vibration), if the vibration component does not attenuate and any of the above conditions 1 to 4 is met, the servo amplifier 100 judges that the notch filter 141 needs to be reset. In this case, the servo amplifier 100 changes the notch frequency f1 of the notch filter 141 to the notch frequency f2.

[0037] Here, even if the notch frequency f1 of the notch filter 141 is changed to the notch frequency f2, if the vibration component does not attenuate and any of the above conditions 1 to 4 is met, the servo amplifier 100 determines that resetting is necessary. In this case, since the vibration frequency f3 and the notch frequency f2 are within a certain range (close to each other), the notch frequency f2 of the notch filter 141 is not changed, but the strength of the notch filter 141 is changed. This changes the depth of the notch frequency f2. Thereafter, the servo amplifier 100 obtains the Peak to Peak (PP) and the vibration period, and if none of the above conditions 1 to 4 is met, it determines that resetting of the notch filters 141 and / or 142 is not necessary.

[0038] In addition, when the vibration component is not attenuated, for example, when the notch frequency of notch filter 141 is set to f2, and any of the above conditions 1 to 4 is met, and the vibration frequency is f1 (or nearby), servo amplifier 100 sets the notch frequency of other notch filter 142 to f1.

[0039] Next, the auto-tuning process of the motor control device M will be described with reference to Fig. 4. Note that the following describes a case related to vibration reduction through torque adjustment.

[0040] (Step S101) The servo amplifier 100 determines whether the target position has been changed. In this case, if there is no change in the target position from a controller (not shown), the servo amplifier 100 determines that the target position will not be changed (step S101: No), and proceeds to step S103. On the other hand, if there is a change in the target position from a controller (not shown), the servo amplifier 100 determines that the target position has been changed (step S101: Yes), and proceeds to step S102.

[0041] (Step S102) The servo amplifier 100 initializes various parameters of the torque adjustment unit 140 .

[0042] (Step S103) The servo amplifier 100 acquires a torque command value included in the adjustment command from the torque adjustment unit 140 .

[0043] (Step S104) The servo amplifier 100 judges whether the acquired torque command value is equal to or greater than the limit. In this case, the servo amplifier 100 compares the torque command limit value stored in a limit value table indicating the allowable torque of the motor 300 (not shown) with the acquired torque command value, and if it determines that the torque command value is not greater than or equal to the limit (step S104: No), it proceeds to step S106. On the other hand, if the servo amplifier 100 determines that the acquired torque command value is equal to or greater than the torque command limit value stored in the limit value table (step S104: Yes), the process proceeds to step S105.

[0044] (Step S105) The servo amplifier 100 activates a tuning stop flag in a tuning table (not shown).

[0045] (Step S106) The servo amplifier 100 monitors the torque command value. In this case, the servo amplifier 100 monitors, for example, the torque command value of the adjustment command from the torque adjustment unit 140 while the motor is in operation.

[0046] (Step S107) The servo amplifier 100 obtains the Peak to Peak (PP) of the vibration component. In this case, the servo amplifier 100 obtains Peak to Peak (PP), which is the difference (amplitude) between the maximum value P1 and the minimum value P2 of the vibration component, as shown in FIG. 2A.

[0047] (Step S108) The servo amplifier 100 determines the vibration periods S1 and S2. In this case, the servo amplifier 100 obtains vibration periods S1, S2 that are the difference times between the maximum values ​​P1, P3 and between the minimum values ​​P2, P4 of adjacent vibration components, as shown in FIG. 2A.

[0048] (Step S109) The servo amplifier 100 determines whether the condition is met. In this case, if the Peak to Peak (PP) and the vibration periods S1 and S2 obtained in steps S107 and S108 do not satisfy either of the above conditions 1 and 2, the servo amplifier 100 determines that conditions 1 and 2 are not satisfied (step S109: No) and ends the process. On the other hand, if Peak to Peak (PP) and the vibration periods S1 and S2 meet either of the above conditions 1 and 2, the servo amplifier 100 determines that condition 1 or 2 is satisfied (step S109: Yes), and proceeds to step S110. As described above, even if Peak to Peak (PP) is small, continuous oscillation can be unpleasant for humans. In this case, the servo amplifier 100 also determines whether the above conditions 3 and 4 are satisfied.

[0049] (Step S110) The servo amplifier 100 sets the notch filter 141 . In this case, when the servo amplifier 100 determines that any one of the conditions 1 to 4 is satisfied, it sets the notch frequency of the notch filter 141 and / or 142 to the period of the vibration component immediately before the determination.

[0050] (Step S111) The servo amplifier 100 determines whether the notch filter 141 needs to be reset. In this case, as shown in FIG. 3, even if the notch frequency f1 of the notch filter 141 is set to the period of the vibration component immediately before the judgment, if the vibration component does not attenuate and any of the above conditions 1 to 4 is met, the servo amplifier 100 judges that the notch filter 141 needs to be reset (step S111: Yes) and proceeds to step S112. In contrast, when the servo amplifier 100 sets the notch frequency f1 of the notch filter 141 to the period of the vibration component immediately before the judgment, for example, if the vibration component attenuates and none of the above conditions 1 to 4 is met, it judges that there is no need to reset the notch filter 141 (step S111: No) and terminates the processing.

[0051] (Step S112) The servo amplifier 100 resets the notch filter 141 . In this case, servo amplifier 100 changes notch frequency f1 of notch filter 141 to notch frequency f2. Here, even if notch frequency f1 of notch filter 141 is changed to notch frequency f2, if the vibration component is not attenuated and any of the above conditions 1 to 4 is met, servo amplifier 100 does not change notch frequency f2 of notch filter 141, but changes the strength of notch filter 141, since vibration frequency f3 and notch frequency f2 are within a certain range (close to each other). This changes the depth of notch frequency f2. When the vibration frequency is (near) f1, the servo amplifier 100 sets the notch frequency of the other notch filter 142 to f1. Thereafter, the servo amplifier 100 obtains Peak to Peak (PP) and the vibration periods S1 and S2, and if none of the above conditions 1 to 4 is met, the resetting of the notch filter 141 ends.

[0052] Next, the vibration level analysis process by the servo amplifier 100 will be described with reference to Fig. 5. Note that the following description is an example of the details of the procedures of steps S107 and S108 in Fig. 4.

[0053] (Step S201) The servo amplifier 100 determines whether the polarity is positive or negative. In this case, when the servo amplifier 100 acquires the threshold value b during the analysis of the vibration component, it determines that the polarity is positive (step S201: positive), and proceeds to step S202. On the other hand, when the servo amplifier 100 acquires the threshold value a during the analysis of the vibration component, it determines that the polarity is negative (step S201: negative), and proceeds to step S209.

[0054] (Step S202) The servo amplifier 100 executes a flow for searching for the maximum value and judges whether it is equal to or greater than the maximum value. In this case, if the current value does not exceed the maximum value during the analysis of the vibration component, the servo amplifier 100 determines that the current value is less than the maximum value (step S202: No), and proceeds to step S204. On the other hand, if the current value exceeds the maximum value during the analysis of the vibration component, the servo amplifier 100 determines that the current value is equal to or greater than the maximum value (step S202: Yes), and proceeds to step S203.

[0055] (Step S203) The servo amplifier 100 updates the maximum value to the current value.

[0056] (Step S204) The servo amplifier 100 judges whether it is equal to or less than the threshold value. In this case, if the servo amplifier 100 determines during analysis of the vibration component that the vibration component is equal to or greater than the threshold value a (step S204: No), the process ends. On the other hand, if the servo amplifier 100 determines that the output voltage is equal to or lower than the threshold value a (step S204: Yes), the process proceeds to step S205. It should be noted that the servo amplifier 100 detects vibration when it determines that the vibration is equal to or less than the threshold value a.

[0057] (Step S205) The servo amplifier 100 judges whether or not a previous measurement has been performed. In this case, if there is no previous measurement (step S205: No), the servo amplifier 100 proceeds to step S207. On the other hand, if there is a previous measurement (step S205: Yes), the servo amplifier 100 proceeds to step S206. If there is no previous measurement, the servo amplifier 100 cannot measure the amplitude and vibration periods S1 and S2 in the first measurement, and therefore does not detect vibration.

[0058] (Step S206) The servo amplifier 100 acquires the amplitude and vibration periods S1 and S2.

[0059] (Step S207) The servo amplifier 100 changes the minimum value to the current value.

[0060] (Step S208) The servo amplifier 100 changes the polarity to negative.

[0061] (Step S209) The servo amplifier 100 judges whether it is equal to or less than the minimum value. In this case, if the servo amplifier 100 determines during analysis of the vibration component that the current value is not equal to or less than the minimum value (step S209: No), the process proceeds to step S211. On the other hand, if the servo amplifier 100 determines during the analysis of the vibration component that the current value is equal to or less than the minimum value (step S209: Yes), the process proceeds to step S210.

[0062] (Step S210) The servo amplifier 100 updates the maximum value to the current value.

[0063] (Step S211) The servo amplifier 100 judges whether or not it is equal to or greater than the threshold value. In this case, if the servo amplifier 100 determines during analysis of the vibration component that the vibration component is equal to or greater than the threshold value b (step S211: Yes), the servo amplifier 100 proceeds to step S212. On the other hand, if the servo amplifier 100 determines that the difference is equal to or less than the threshold b (step S204: No), the process ends.

[0064] (Step S212) The servo amplifier 100 judges whether or not a previous measurement has been performed. In this case, if there is no previous measurement (step S212: No), the servo amplifier 100 proceeds to step S214. On the other hand, if there is a previous measurement (step S212: Yes), the servo amplifier 100 proceeds to step S213. If there is no previous measurement, the servo amplifier 100 cannot measure the amplitude and vibration periods S1 and S2 in the first measurement, and therefore does not detect vibration.

[0065] (Step S213) The servo amplifier 100 acquires the amplitude and vibration periods S1 and S2.

[0066] (Step S214) The servo amplifier 100 changes the maximum value to the current value.

[0067] (Step S215) The servo amplifier 100 changes the polarity to positive.

[0068] As described above, in this embodiment, the servo amplifier 100 that adjusts the gain of the motor 300 acquires the amplitude and vibration period of the vibration component included in the torque command value, and if the amplitude and vibration period satisfy certain conditions, it is determined that setting of the notch filters 141 and / or 142 is necessary, and the notch frequency of the notch filters 141 and / or 142 is set to the period of the vibration component immediately before the determination. This eliminates the need to extract vibration through Fourier series expansion and to acquire the amount of data required for frequency analysis, thereby shortening the auto-tuning process. [Explanation of symbols]

[0069] 100 Servo Amplifier 110 Position adjustment section 120 Feedforward control section 130 Feedback control section 140 Torque adjustment unit 141, 142 Notch filter 150 Subtractor 160 Adder / Subtractor 170 Current control section 300 Motor M Motor control device

Claims

1. A servo amplifier that adjusts the motor gain; a notch filter; The servo amplifier recognizes a peak of the torque command value from a characteristic of the torque command value over time, recognizes the amplitude of a vibration component from a peak-to-peak value in the characteristic, and recognizes the vibration period of the vibration component from the time between peaks. If the amplitude and the vibration period satisfy certain conditions, it determines that setting of the notch filter is necessary, and sets a notch frequency of the notch filter to a frequency corresponding to the period of the vibration component immediately before the determination. A motor control device comprising:

2. 2. The motor control device according to claim 1, wherein the servo amplifier changes a notch frequency and / or strength of the notch filter if the vibration component is not attenuated after the notch filter is set.

3. A motor control method comprising: a servo amplifier that adjusts a gain of a motor recognizing a peak of a torque command value from a characteristic of the torque command value over time; recognizing the amplitude of a vibration component from a peak-to-peak value in the characteristic and the vibration period of the vibration component from the time between peaks; and if the amplitude and the vibration period satisfy certain conditions, determining that setting a notch filter is necessary, and setting a notch frequency of the notch filter to a frequency corresponding to the period of the vibration component immediately before the determination.

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