TW200830688A - Motor control device, and its control method - Google Patents

Abstract

Provided are a motor control device, which can estimate an inertial moment highly precisely within a small working range and even in case the gradient of a low frequency is not fixed due to the influence of friction or control, and a control method for the device. The motor control device comprises a speed signal generating unit (2) for generating a speed signal from a position signal, and a current control unit (1) for controlling a motor current on the basis of a torque command. Further comprised are a test torque command generating unit (3) for generating a test torque command containing multiple frequency components, a frequency characteristic calculating unit (4) for calculating the frequency characteristics from a response of the speed signal to the test torque command, and a mechanical parameter calculating unit (6) for calculating a mechanical parameter from the frequency characteristics.

Description

200830688 IX. Description of the Invention [Technical Field] The present invention relates to a motor control device capable of estimating a mechanical model. [Prior Art] In the past, when the moment of inertia of the machine was confirmed, the range of the degree of operation of the predetermined mode was actually driven, and the moment of inertia (moment of inertia) was obtained based on the torque command and the speed of the output. In addition, the loyal moment of inertia is based on the inclination of the low frequency of the frequency characteristic (Japanese Patent Literatures 2 and 3). The parameters of the motor control device can be optimally adjusted by using the 惯性 of the moment of inertia. It can also be used to perform a model of the feed forward controller or observer before the vibration control to improve the mechanical characteristics. Φ Patent Document 1: Japanese Laid-Open Patent Publication No. Hei. No. Hei. No. Hei. No. Hei. No. 2002-304219. <Problems to be Solved by the Invention> In the case of the conventional mechanical model estimating device, in the case of the conventional technique of Japanese Patent Literature 1, since the range of the degree of operation of the predetermined mode is actually driven, there is a case When the machine's operating range is not reached, it is not possible to perform the correct action. Further, in the prior art of Japanese Patent Publications 2 and 3, since the method of obtaining the moment of inertia by using the low-frequency inclination of the frequency characteristic is employed, there is a case where the inclination of the low frequency is not necessarily caused by the influence of friction or control. In the case, the accuracy of the confirmation is not obtained. The present invention has been made in view of the above problems, and an object thereof is to provide a motor capable of estimating a moment of inertia with high accuracy even in a case where the inclination of a low frequency is not necessarily affected by friction or control in a small operation range. Control device and its control method. <Means for Solving the Problem> In order to solve the above problems, the present invention includes the following items. The motor control device according to the first aspect of the invention is the motor control device including a speed signal generating unit that generates a speed signal by a position signal, and a current control unit that controls the motor current according to the torque command. A test torque command generation unit that generates a test torque command including a plurality of frequency components, and a real frequency characteristic calculation unit that calculates a real machine frequency characteristic by reacting the speed signal to the test torque command, and a basis The aforementioned machine frequency characteristics are used to generate mechanical parts of the mechanical parameters. The motor control device according to the second aspect of the present invention is the position control unit for generating a speed command by a position command and the position signal, and the motor control device according to the first aspect of the present invention. The speed command and the speed signal generate a speed control unit for the torque command. -5-200830688 The motor control device according to claim 3 of the present invention, as in the first claim of the present invention, wherein the actual frequency characteristic includes: a resonance frequency and an amplitude thereof, an anti-resonance frequency And its amplitude. The motor control device according to the fourth aspect of the present invention is as in the first or second aspect of the invention, wherein the mechanical parameter generating portion is configured to make the total moment of inertia and the braking coefficient of the two inertia coefficient models. Repeat small changes to make the frequency characteristics and real frequency of the two inertia coefficient model

The rate characteristics are approximately the same, and the total moment of inertia and the aforementioned braking coefficient are determined as the number of turns. The motor control device according to claim 5 of the present invention is as in the fourth aspect of the patent application scope of the present invention, wherein the aforementioned two inertia coefficient model is represented by the formula (1), the anti-resonance frequency and the resonance frequency. The gain of the intermediate frequency is expressed by the equation (2), [number 1] ice - 丄, less + 2 (five) + 岣 2) m

Js, l i?2+ is [number 2]

\ -2έό2ω^2 + 〇).HAf Αζ2ω^ω2 J Here ' J : total moment of inertia, ω η : resonance frequency, ω L : anti-resonance frequency, ω ··test frequency, ^ .: braking coefficient, s : Laplace operator. The motor control device according to claim 6 of the present invention is as in the fifth aspect of the patent application scope of the present invention, wherein the mechanical parameter generation -6 - 200830688 section is based on the actual frequency characteristic and the aforementioned two inertia system The gain of the mathematical model frequency characteristic from the anti-resonance frequency to the range of the resonance frequency is compared. 'If the gain of the actual frequency characteristic is large, the total moment of inertia of the two inertia coefficient model is slightly increased, if it is small, Let the total moment of inertia of the two inertia coefficient model be slightly reduced until it is approximately the same. The motor control device according to claim 7 of the present invention is as in the sixth aspect of the invention, wherein the magnitude of the gain is compared from the anti-resonance frequency to the resonance frequency. To decide. The motor control device according to claim 8 of the present invention is the sixth item of the patent application scope of the present invention, wherein the initial enthalpy of the total moment of inertia is respectively expressed by the formula (3), [the number 3] () Only the db conversion gain Yh of the anti-resonance frequency of the Yl. frequency characteristic: the db conversion gain of the resonance frequency. The motor control device according to claim 9 of the present invention is the sixth item of the patent application scope of the present invention, wherein the initial 値 of the total moment of inertia is expressed by the formula (5), (4) J = 'Uh/ C〇l)/(cvYm) 200830688 Only 'ΥΜ: the real frequency characteristic Ο) =, (ω Η · Yl) gain. A motor control device according to claim 10 of the present invention is a motor control device including a speed signal generating unit that generates a speed signal by a position signal and a current control unit that controls a motor current according to a torque command. The control method includes the steps of: inputting a test torque command including a plurality of frequency components to a current control unit, and arranging the actual machine frequency characteristic; and the actual frequency characteristic and the two inertia system a step of comparing the frequency characteristics of the mathematical model, and repeatedly correcting the total moment of inertia and the braking coefficient, and correcting the step of the real frequency characteristic and the gain of the frequency characteristic of the two inertia coefficient model, and the gain substantially Determine the total moment of inertia and the braking coefficient as a parameter step. [Effect of the Invention] According to the first aspect of the invention, it is possible to provide a case where the inertia moment is confirmed by applying the frequency analysis result in the open circuit, and the low frequency band is lowered in response to the influence of the annual friction or the controller. The object of the frequency characteristic is also the motor control device that is confirmed with high precision. According to the second aspect of the patent application of the present invention, it is possible to provide a case where the inertia moment is confirmed when the frequency analysis result in the configuration of the closed circuit controlled by the controller is applied, and the effect is reduced by the influence of the viscous friction or the controller. The object of the frequency characteristics of the low frequency band is also the motor control device that is confirmed with high precision. * 8 - 200830688 According to the third to ninth aspects of the patent application of the present invention, it is possible to provide a high-precision estimation with high accuracy even if the inclination of the low frequency is not necessarily affected by friction or control. Motor control device for inertia moment. According to the first aspect of the patent application of the present invention, it is possible to provide a motor control capable of estimating the inertia moment with high accuracy even in a case where the inclination of the low frequency is not necessarily caused by friction or control. The method of control of the device. [Embodiment] Hereinafter, specific embodiments of the present invention will be described based on the drawings. Embodiment 1 FIG. 1 is a block diagram showing the configuration of a first sinus embodiment of the present invention. FIG. 1 is a current control unit, and FIG. 2 is a speed signal generating unit, and FIG. 3 is a test torque. Command generation unit, Fig. 4 is a frequency characteristic calculation unit 'Fig. 5 is a mechanical model calculation unit, Fig. 6 is a mechanical model, and Fig. 1 1 is a motor 'Fig. 12 is a position detector, and Fig. 13 is a machine. . The current control unit 1 converts the torque command into a current command, and the current deviation between the current command and the motor current is subjected to P ID control processing to generate a voltage command, and the voltage command is PWM-driven to drive the power converter to supply electric power to the motor. The speed signal generating unit 2 obtains a time difference between the position signals of the position detectors coupled to the motor, and generates a speed signal. The test torque command generating unit 3 generates a torque command including a plurality of frequency components when the motor control device is not in the normal operation mode but in the test mode 200830688, and inputs it to the current control unit 1. The frequency characteristic calculation unit measures the speed signal when the test torque command is input to the current control unit 1, and calculates the frequency characteristic. The frequency of the valley of the frequency characteristic of the mechanical model calculation unit 5 is estimated as a combination of the resonance frequency and the anti-resonance frequency, and several candidates are extracted, and the two inertia systems to be modeled are determined. A flow chart of the method of the invention is shown in Figure 3. As shown, the method of the present invention is processed through the seven steps of steps 1 through 7. Step 1 is to input a test torque command containing a plurality of frequency components to the current control unit to measure the response of the speed signal. Step 2 calculates the frequency characteristics of the machine based on the input test torque command and the response of the measured speed signal. Step 3 performs a valley detection on the result of the calculation of the frequency characteristic, and estimates a combination of the resonance frequency and the anti-resonance frequency as a two-inertia model, and extracts several candidates. Step 4 determines the set of two inertial systems to be modeled according to the purpose. For example, when the inertia moment of the rigid body mode of the entire system is required, the lowest frequency is selected. Further, in the case of the purpose of adjusting the high-frequency vibration by the vibration suppression control, the resonance frequency causing the problem and the anti-resonance frequency corresponding to the resonance frequency are selected. When there are a plurality of resonance frequencies, it is not easy to automatically discriminate, or if it is desired to set a frequency that is directly targeted, the resonance frequency and the anti-resonance frequency are manually selected via step 5. Step 6 is to adjust the model by performing a curve matching of the two inertial system models on the selected combination of the resonant frequency and the anti-resonant frequency. Step 7 carefully confirms the attenuation of the moment of inertia and vibration from the model after the evaluation, plus the resonance frequency and the anti-resonance frequency. Further, the dotted line portion 8 is a portion belonging to Japanese Patent Laid-Open Publication No. 6. -10- 200830688 Hereinafter, steps 6 and 7 will be described in detail. When the resonance frequency ω Η, the anti-resonance frequency ω L 'attenuation Γ, and the total moment of inertia J are set, the transmission function from the torque of the two inertia system models to the speed is expressed by the equation (1).

This transfer function is expressed by Equation 2 as a function of the frequency ω when the gain in the frequency band is expressed by the db conversion gain ω (ω). Here, if the attenuation Γ is very small, the intermediate point between the resonance frequency ω Η and the anti-resonance frequency 0L is expressed by Equation 5. [Equation 4] 4^1 = 201cgL..W^^l- 1 <5) ^ 1 J {ω£ + ωΗ X&L + 3ωΗ)) Gain of anti-resonance frequency obtained by frequency response operation In the case of YL and the gain of the resonance frequency is YH, the total moment of inertia J can be calculated by the equation (3). The gain is preferably averaged around the number of points. The parameters which are approximated by the equation (5) and (the two are used as the initial 値' are matched by the curve of the model using the equation (2) and the frequency reaction calculation result obtained by the measurement. Various methods such as the least square method or the genetic algorithm can be used for the adaptation. However, the area comparison and the intermediate point comparison between the antiresonance frequency and the resonance frequency shown in FIG. 4 will be described. It is shown that the real frequency characteristic obtained by the measurement, the two inertia coefficient model frequency characteristic 2, the g-estimation starting point 3, and the evaluation end point 4. 3 correspond to the anti-resonance frequency '4 corresponding to the resonance frequency. When the adjustment condition is indicated, it is as follows. 200830688 First, for the attenuation coefficient r, when the gain obtained by the frequency characteristic calculation is Υ (ω), the condition is adjusted by the condition of equation (6). ] d+ j if ^r(&) ' p $-方tf Σ,Φ) (6) where '(5 is an arbitrary integer 値, as for the total moment of inertia j is

The following conditions are adjusted. [Number 6] J - J + σ if J = σ if

m where ' σ is an arbitrary integer 値. When the model is limited to the two inertia system, the total moment of inertia can be easily obtained by using the condition of the equation (7). Therefore, the attenuation coefficient can be obtained by the degree of matching between the determination model and the frequency characteristics obtained by the measurement. An example of the result of confirming the specificity of the moment of inertia of the rigid body mode of the entire system is shown in Figs. 3 and 4. Fig. 3 is a view showing the result of confirmation obtained by a conventional technique. Fig. 6 is a view showing the result of confirmation obtained by the present invention. For the measured frequency characteristic 1, the model confirmed by the curve adaptation is 5, and the model of the present invention is 2. In the case of a machine in which the moment of inertia of the rigid body mode is exactly 60 times, the conventional method is confirmed to be an average of 70 times the inclination of the low frequency band. On the other hand, it is confirmed that the enthalpy is 55.5 times by using this method. The method of -12-, 200830688 also needs to confirm the moment of inertia with higher precision. Embodiment 2: Fig. 2 is a block diagram showing the configuration of a second embodiment of the present invention. In the first embodiment, the position control unit 7 and the speed control unit 8 are added. Further, in order to confirm the total moment of inertia, the frequency of the intermediate point between the resonance frequency and the anti-resonance frequency may be selected as . When f = 〇, the gain Η, ( ω ) of the two inertial system models in the frequency ω μ is expressed by the equation (8). HJ (ω)= I GJ 〇ω) | =(1/]/ω ) /ω ) (8) LHL / In addition, the gain of the midpoint of the actual frequency characteristic is set to ΥΜ, then the total moment of inertia J is given by (9) )To represent. J = /"(ω /ω )/ω /Ύ (9)

Η L L Μ Κ J

Use this as an initial flaw. The obtained inertia moment adopts the frequency and gain of the resonance point and the anti-resonance point. Therefore, even for the model processing of the multi-inertial structure, the spring constant and the moment of inertia of the respective spring elements are obtained, so that it can be applied to this phase. The most appropriate setting of the corresponding filter [Industrial Applicability] The motor control device of the present invention, even in a small operating range, is affected by friction or control from -13 to 200830688, resulting in low frequency tilt. In the case of the first one, the inertia moment can be estimated with high accuracy. Therefore, the first robot or the working machine can be expected to be applied to general industrial machinery. Further, although the present invention is based on the assumption that it is incorporated in the motor control device, it can be applied as an inertia moment estimating device. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a block diagram showing the configuration of the present invention. Fig. 2 is a block diagram showing the configuration of the present invention. Figure 3 is a flow chart showing the method of the present invention. Fig. 4 is a view showing a method of fitting the curve of the present invention. Figure 5 is a graph showing the results of the confirmation of the conventional method. Figure 6 is a diagram showing the results of confirmation of the present invention. [Description of main component symbols] • 1 : Current control unit 2 : Speed signal generation unit 3 : Test torque command generation unit 4 : Frequency characteristic calculation unit 5 : Mechanical parameter calculation unit 6 : Mechanical parameter 7 : Position control unit 8 : Speed control Part 11: Motor-14- 200830688 12 : 13 : 21 : 22 : 23 : 24: 25 : The position detection unit mechanically obtains the frequency response obtained by the measurement. The frequency response evaluation of the two inertial frame model starts the point evaluation end point just the system model Frequency characteristics

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Claims (1)

200830688 X. Patent Application No. 1 A motor control device is provided with a speed signal generating unit that generates a speed signal from a position signal and a current control unit that controls a motor current according to a torque command, and is characterized in that: a test torque command generating unit for a test torque command of a plurality of frequency components; and a real machine frequency characteristic calculating unit that calculates a real machine frequency characteristic by a response to the speed signal of the test torque command; and based on the actual frequency characteristic A mechanical parameter generating unit that generates mechanical parameters. The motor control device according to claim 1, further comprising: a position control unit that generates a speed command by the position command and the position signal; and the torque command and the speed signal to generate the torque command Speed control unit. 3. The motor control device according to claim 1, wherein the real frequency characteristic includes: a resonance frequency and an amplitude thereof, an anti-resonance frequency, and an amplitude thereof. 4. The motor control device according to claim 1 or 2, wherein the mechanical parameter generating unit causes the total moment of inertia and the braking coefficient of the two inertia coefficient models to be slightly changed in order to make the two inertia coefficient model The frequency characteristics are substantially identical to the actual machine frequency characteristics, and the total inertia moment and the aforementioned braking coefficient are determined as parameters. 5. The motor control device according to claim 4, wherein the 'two inertia coefficient model is expressed by the formula (1), and the gain of the intermediate frequency of the anti-resonance-16-200830688 frequency and the resonance frequency is Sub (2) to represent ω 2 buckle 4'- 2o^ml + fi>z4 + Αζ2ω^ώ2 ^ωΖ2ω^ωΑ — 2α>έα>^2 η> + Αζ^ω^ω2 ^ Here, J: total inertia Torque, ω Η : resonance frequency, ω L : anti-resonance frequency,: test frequency, Γ: braking coefficient, S: Laplace Φ operator. 6. The motor control device according to claim 5, wherein the mechanical parameter generating unit ranges the anti-resonance frequency to the resonance frequency of the real frequency characteristic and the frequency characteristic of the two inertia coefficient model. The gain is compared. If the gain of the sinus machine frequency characteristic is large, the total moment of inertia of the two inertia coefficient model is slightly increased. If it is small, the total moment of inertia of the two inertia coefficient model is slightly reduced until Repeatedly as usual. The motor control device according to claim 6, wherein the magnitude of the gain is determined by comparing a gain area from an anti-resonance frequency to a resonance frequency. 8. The motor control device according to claim 6, wherein the initial enthalpy of the total moment of inertia is respectively expressed by equation (3), τ-2ω.Η2{3ωίή·ώΗ) ... • ~nf, +v , - (?) e40 1 B ^L\wh ^·ω.Η f〇y^3wk). YL: db conversion gain YH of the anti-resonance frequency of the real machine frequency characteristic: db conversion gain of the resonance frequency. -17- 200830688. The motor control device according to claim 6, wherein the initial 惯性 of the total moment of inertia is expressed by the formula (5), ] = ^(ωΗ/ω^/(ω^ΥΜ) (4) Only ' Υ Μ : Gain of 0 = \/~ ( ω Η · ω L ) of the frequency characteristic of the machine. 1 〇. A control method for the motor control device that has the speed generated by the position Φ signal A signal signal generating unit and a motor control device control method for controlling a motor current based on the torque command, wherein the method includes the following steps: inputting a test torque command including a plurality of frequency components to a step of obtaining a real machine frequency characteristic by the current control unit; and a step of comparing the actual frequency characteristic with the frequency characteristic of the two inertia coefficient model; and # repeating the total moment of inertia and the braking coefficient by a minor correction a step of matching the frequency characteristic of the real machine with the gain of the frequency characteristic of the two inertia coefficient model; and after the gains are substantially identical, determining the total moment of inertia and the braking coefficient as parameters Steps to number. -18-