JP5621274B2 - Motor torque control device - Google Patents

Description

  The present invention relates to a motor torque control device, and more particularly, to periodic disturbance suppression and mechanical resonance suppression of torque output in a motor control device that generates an arbitrary waveform torque output to the motor.

  The motor in principle generates torque ripple (torque pulsation), which causes various problems such as adverse effects on vibration, noise, riding comfort, and mechanical resonance. In particular, an embedded magnet PM motor (IPMSM), which has become popular in recent years, generates a combination of cogging torque ripple and reluctance torque ripple. As a countermeasure, various methods for superimposing a compensation current for canceling the torque ripple on the torque command have been studied.

  However, for example, in the method of performing feedforward compensation using a mathematical analysis model, there is a concern about the influence of analysis errors. Further, in the method of storing the feedback learning control result at the steady operating point and performing feedforward compensation, it takes time to appropriately adjust the control parameter for each operating point, and online compensation becomes difficult. Further, the method for reducing the current ripple is not always optimally suppressed from the viewpoint of torque ripple. In addition, torque ripple observer compensation methods have been studied, but the characteristics during variable speed operation and on-line feedback suppression verification have been insufficient.

  The inventors of the present application have already proposed a feedback suppression control method using an axial torque meter in order to suppress the torque ripple, which is a cause of mechanical resonance, with high accuracy with respect to the above problem (see, for example, Non-Patent Document 1). . This control method focuses on the periodicity of torque ripple and constructs a control system that compensates for each pulsation frequency component, and also has a function that automatically adjusts parameters to respond quickly to changes in the operating state using the system identification result. The details of this control method will be described below.

(1) Basic Configuration of Torque Ripple Suppression Control Device FIG. 4 is a control block diagram of a conventional torque ripple suppression control device. The figure is applied to a system in which a load is torque-excited by a motor.

A motor 1 that is a torque ripple generation source and some load device 2 are coupled by a shaft 3, and its shaft torque is measured by a torque meter 4 and input to a torque ripple suppression device 5. Moreover, the rotor position (phase) information of a motor is input using rotational position sensors 6, such as a rotary encoder. The torque ripple suppression device 5 includes torque pulsation suppression means, and gives the inverter 7 a command value obtained by adding a torque pulsation compensation current to the current command value generated based on the torque command value (or speed command value). In the example of FIG. 4, in consideration of the current vector control by the inverter 7, the d-axis and q-axis current command values id ^* and iq ^* on the rotation coordinates (orthogonal dq axes) synchronized with the rotation of the motor are given. Yes.

It is known that torque ripple (torque pulsation) periodically occurs according to the rotor position due to the structure of the motor. Therefore, means for extracting a torque ripple frequency component in synchronism with the motor rotation is used to convert the torque ripple of arbitrary order n into cosine and sine coefficients T _An and T _Bn [Nm]. The exact measurement means of the torque ripple frequency component includes Fourier transform, etc. However, if importance is placed on the ease of operation, a single-phase harmonic rotation coordinate system based on the rotation phase θ [rad] as shown in equation (1) A torque ripple frequency component can be extracted by passing through a low-pass filter.

ω _f : filter cutoff frequency [rad / s], T _det : shaft torque detection value [Nm]
The torque ripple suppression device 5 performs torque ripple suppression control using the coefficients T _An and T _Bn extracted by the above formula, and the cosine / sine coefficients I _An and I _Bn [ampere] of the compensation current iqc ^* [ampere] of the arbitrary frequency component. Is generated. Conversion to the compensation current iqc ^* is obtained by the following equation (2) using the same rotation phase θ as that at the time of conversion, and this compensation current is superposed on the q-axis current command value and normal vector control is performed.

  FIG. 5 is a control block diagram of the torque ripple suppression device based on the torque ripple compensation current table. The symbols in the figure have the following meanings.

T ^* : torque command value, ω: rotational speed detection value, θ: rotational phase detection value, iqc ^* : torque ripple compensation current, id: d-axis current detection value, id ^* : d-axis current command value, iq: q-axis current Detected value, iq ^* : q-axis current command value, iu, iv, iw: u, v, w-phase current, iqo ^* : q-axis current command value (before compensation current superposition), I _An : compensation current cosine coefficient, I _Bn : compensation current sine coefficient, abz: rotation sensor signal. Note that the subscript n is an nth-order component torque ripple.

In FIG. 5, the command value conversion unit 11 converts the torque command value T ^* into the d-axis and q-axis current command values Id ^* and Iqo ^* of the rotation dq coordinate system in vector control (for example, generally the maximum torque / current A conversion formula or a table that realizes the control is used), and the torque pulsation is suppressed by superimposing the torque pulsation compensation current iqc ^* on the q-axis current command value Iqo ^* . In the example of FIG. 5, the compensation current iqc ^* is superimposed on the q-axis current command value, but may be applied to the d-axis current or both the d-axis and the q-axis. Alternatively, in a system where interference of dq axis current does not become a problem, a torque pulsation compensation signal may be directly superimposed on the torque command value.

  The current vector control unit 12 drives the load device 14 by performing a current vector control operation on a general orthogonal rotating coordinate system d-axis q-axis and driving the motor 13 by vector control. The coordinate conversion unit 15 converts the three-phase alternating currents iu, iv, iw and the motor rotation phase θ detected by the current sensor 16 into currents id, iq in a dq axis orthogonal rotation coordinate system synchronized with the motor rotation coordinates. The rotation phase / speed detection unit 17 converts the rotation sensor signal abz of the rotation position sensor 18 such as an encoder into information on the rotation speed ω and the rotation phase θ.

As described above, the compensation current table 19 is a two-dimensional table that receives the torque command value T ^* and the rotational speed ω and outputs the compensation current cosine coefficient I _An and the sine coefficient I _Bn from these inputs. The compensation current generator 20 generates a compensation current command value by the above equation (2) and superimposes it on the q-axis current command value. Instead of the compensation current table 19, torque ripples T _An and T _Bn are obtained from the shaft torque T _det detected by the shaft torque detector 4 in FIG. 4 and the rotational phase θ, and the compensation current cosine coefficient is obtained from these and the rotational speed ω. A method of obtaining I _An and sine coefficient I _Bn may be used.

FIG. 6 is an example of a three-dimensional compensation current table characteristic in the test system, and suppresses torque ripple of the sixth-order component using the sixth-order torque ripple compensation cosine coefficient I _an and the sine coefficient I _bn .

(2) System Identification The system configuration shown in FIG. 4 is a multi-inertia torsional resonance system due to the moment of inertia of the PM motor 1, the load device 2, the torque meter 4, the coupling 3, and the like. When the detected value of the shaft torque is fed back, since there are a plurality of resonance / anti-resonance frequencies, the suppression control parameter must be appropriately determined according to the operation state. If the learning time of the control parameter is long, there is a risk of increasing the mechanical resonance phenomenon, so a quick automatic adjustment function is necessary.

Therefore, in Non-Patent Document 1, in order to derive a variable nominal control parameter adapted to the rotational speed change, the system transfer function from the output value to the input value of the torque ripple suppression device 5 in FIG. 4, that is, the compensation current command in FIG. It is identified as a frequency transfer function from the value iqc ^* to the detected value T _det of the shaft torque detector 4. The system identification method is arbitrary, but the shaft torque detection value T _det when a Gaussian noise signal is given to iqc ^* in an open loop is measured for 20 seconds at a calculation period of 100 μs, and the frequency is calculated from the ratio of input and output power spectral densities The result of non-parametric estimation of the transfer function is shown in FIG. 7 (actual machine characteristics including mechanical system, inverter current response, torque meter response, dead time, etc.). In addition, the result of parametric identification in the case of approximating a four-inertia system from the tendency of the frequency transfer function is also shown. There are various optimization methods for approximation, but errors in amplitude characteristics up to 1 kHz in the frequency domain were evaluated, and constrained nonlinear minimization (sequential quadratic programming) was performed.

In FIG. 5, in order to construct a control system with coordinates synchronized with the torque ripple frequency, only an arbitrary frequency transfer function is extracted from the system identification result of FIG. In the steady state, the amplitude / phase transfer function of the system synchronized with the torque ripple frequency can be expressed by a one-dimensional complex vector. Therefore, the system characteristic _Psys in the control system of FIG.

P _Am : Real part of the system characteristic, P _Bm : Imaginary part of the system characteristic, m: Frequency element number of the system identification table For example, the system characteristic from 1 to 1000 [Hz] is expressed by equation (3) for each IHz. In this case, the system identification table can be constructed from the elements of 1000 complex vectors. Only one complex vector is always used in the control system, and P _Am and P _Bm are instantaneously read from the identification table according to changes in the rotational speed (torque ripple frequency change), and converted into complex vectors by linear interpolation. The identified results are applied to suppression control. Since the axes of the real part and the imaginary part are defined with reference to the rotation phase, the cosine coefficient in equation (1) corresponds to the real part component and the sine coefficient corresponds to the imaginary part component.

(3) Compensation current Fourier coefficient learning control method This is a torque ripple suppression control method described as method 1 in Non-Patent Document 1 described above, which is obtained as a Fourier coefficient of a torque ripple frequency component, and from this, the compensation current is calculated by the above equation (2). Find iqc ^* . In this control method, a system transfer function of a frequency component synchronized with the torque ripple frequency is expressed by a one-dimensional complex vector, and a real part and an imaginary part of the torque ripple of an arbitrary frequency component are extracted by Fourier transform or the like. By applying the cosine and sine Fourier coefficients to the real and imaginary parts of the complex vector, a feedback suppression control system is constructed.

  The compensation current coefficient is obtained by an IP (proportional / integral) learning control method. The proportional / integral gain is determined by the model matching method so that the closed loop characteristic of the IP suppression control system matches the pole arrangement of an arbitrary standard system reference model. In addition, since the parameters are automatically adapted using the system identification result and the rotation speed information, the implementation to the multi-inertia resonance system is facilitated.

  Saves the amplitude and phase of the compensation current signal when suppression is completed at an arbitrary steady operating point (steady torque and steady rotational speed), and implements it at multiple operating points to create a two-dimensional table of torque and rotational speed Implement as At this time, it is possible to input the torque / rotational speed information into the table, generate a compensation current from the read compensation current amplitude / phase data, and suppress feedforward.

FIG. 8 is a calculation block diagram of Fourier coefficient learning control. The figure represents only the control system synchronized with the torque ripple frequency component, and uses the identification result of equation (3) as a nominal model. In this method, torque ripple is suppressed by an IP control method in which a proportional term in which cosine (real part) / sine (imaginary part) coefficient command values T _An ^* and T _Bn ^* of the torque ripple component are set to 0 is provided in the preceding stage. When the compensation current is also expressed as a complex vector and superimposed on the system, the torque detection value T _det is expressed by equation (4), and the compensation current I _An . It can be seen that I _Bn interfere with each other.

  Therefore, as shown in FIG. 8, by providing a speed adaptive type non-interference term using the system identification result, the real part and imaginary part suppression control systems are made non-interactive. The closed loop transfer function from the target value to the detected value after decoupling is given by equation (5).

  When the target value response of equation (5) is adapted to the pole placement of the binomial coefficient standard system shown in equation (7), equation (8) can be derived from the coefficient comparison of equations (5) and (7). Is given as a nominal proportional / integral gain.

ω _c : Desired learning control response frequency [rad / s], where ω _c <ω _f / 2.

Since the proportional gain K _{p in the} equation (8) includes components of the real part P _Am and the imaginary part P _Bm of the system identification model that changes according to the speed, even if the rotational speed (torque ripple frequency) changes (7) Serves to maintain the pole placement response of the equation. The learning control response is arbitrarily determined within a range that satisfies the condition. Although the details of the disturbance response are omitted, the result of deriving the gain equation is equivalent to the equation (8).

(4) Periodic disturbance observer compensation method This is a torque ripple suppression control method described as method 2 in Non-Patent Document 1 described above. Since the control parameter automatic adjustment method in the compensation current Fourier coefficient learning control method suppresses disturbance through the adjustment of the IP control gain, the responsiveness to variable speed operation decreases. For this reason, it is recommended that the learning results be tabulated in advance to suppress feedforward.

  Since the periodic disturbance observer compensation method of the present method directly estimates the torque ripple disturbance using the concept of the periodic disturbance observer, it is possible to improve the above responsiveness problem. Therefore, torque ripple can always be suppressed by online feedback even for a system having variable speed and load fluctuation. Similarly to the compensation current Fourier coefficient learning control method, the system identification result expressed by a one-dimensional complex vector is used to provide a function for automatically adjusting the inverse model of the periodic disturbance observer. It has a feature that makes it easy to implement.

Kanno et al., “Examination of torque ripple suppression control method focusing on periodic disturbance of PM motor”, 2009 IEEJ Industrial Application Division Conference, I-615-618, Date: August 31-September 2, 2009 Sun, venue: Mie University

  In a motor control device that generates an arbitrary torque waveform by exciting and superimposing multiple sine wave torque commands of frequency components, if the torque excitation frequency matches the resonance point of the electromechanical system, the torque waveform resonates and vibrates.・ Causes various problems such as noise, equipment damage, and measurement problems. In addition, periodic disturbances in the torque of the motor cause similar problems due to mechanical resonance.

  The compensation current Fourier coefficient learning control method and the periodic disturbance observer compensation method described above are control methods for suppressing the periodic disturbance of torque, but when output control is performed to a torque command value having an arbitrary waveform such as torque excitation control. No consideration is given to a method for suppressing a mechanical resonance phenomenon that may occur.

  An object of the present invention is to provide a torque control device for a motor capable of suppressing periodic disturbance and mechanical resonance of a motor torque output in a motor control device that generates torque output having an arbitrary waveform such as torque excitation. is there.

  In order to solve the above problems, the present invention provides a torque control device for a motor that controls the output of a motor with a torque command value having an arbitrary waveform. It is identified as a system transfer function for each frequency component from to the torque detection value, and a torque command value is generated by a resonance suppression table or resonance suppression calculation using the inverse of the identification result for each frequency component. It is characterized by the configuration of

(1) In a motor torque control device provided with a torque control circuit for controlling the output of a motor that drives a load device to an arbitrary waveform torque command value, the resonance phenomenon of the electric / mechanical system due to the frequency component of the motor torque output And a mechanical resonance suppression control unit that identifies the system transfer function for each frequency component from the torque command value to the torque detection value, and generates the torque command value using a resonance suppression table using the reciprocal of the identification result for each frequency component. It is provided with.

  (2) The mechanical resonance suppression control means expresses the system identification result by an approximate mathematical expression of a system characteristic.

(3) The mechanical resonance suppression control means generates the torque command value in the resonance suppression table, and at the same time, performs periodic disturbance compensation current table or periodic disturbance suppression calculation for suppressing periodic disturbance of the torque output of the motor. There is provided periodic disturbance suppression control means for correcting the torque command value.

(4) the machine resonance suppression control means, when generating a torque output of the arbitrary waveform by superimposing a torque command value of an arbitrary waveform having a plurality of frequency components including the DC component, a plurality of the in parallel resonance suppression table A torque command value is generated.

(5) The torque control circuit is configured to control the motor current by converting the torque command value into a d-axis q-axis current command value of a rotating coordinate system in vector control,
The periodic disturbance suppression control unit corrects a torque command value of only the q-axis current command value.

  (6) The mechanical resonance suppression control means separates the torque command value having an arbitrary waveform having a plurality of frequency components including a DC component into a torque component other than a DC component and a torque component other than a DC component. The torque is converted into a q-axis current command value, and torque components other than direct current are converted into a q-axis current command value considering resonance suppression.

  (7) The periodic disturbance suppression control means suppresses a periodic disturbance of torque by a torque resonance suppression table or a torque resonance suppression calculation using a q-axis current command value including a plurality of frequency components as an input. .

  As described above, according to the present invention, in a motor torque control device that controls the output of a motor with a torque command value having an arbitrary waveform, the resonance phenomenon of the electric / mechanical system due to the frequency component of the torque output is reduced from the torque command value to the torque. The system is identified as a system transfer function for each frequency component up to the detected value, and a torque command value is generated by a resonance suppression table or resonance suppression calculation using the reciprocal of the identification result for each frequency component. In addition, it is possible to suppress periodic disturbance and mechanical resonance of the torque output of the motor in a motor control device that generates torque output of an arbitrary waveform in the motor.

A control block diagram of a torque control device (embodiment 1). A control block diagram of a torque control device (second embodiment). A control block diagram of a torque control device (embodiment 3). The block diagram of the conventional torque control apparatus. The control block diagram of the conventional torque control apparatus. The example of the three-dimensional compensation electric current table characteristic in torque suppression control. The example of the frequency transfer function of a torque control apparatus. Compensation current coefficient calculation block diagram.

(Embodiment 1)
The present embodiment proposes a method of simultaneously suppressing the mechanical resonance phenomenon due to torque excitation while realizing the torque ripple suppression of the motor using the compensation current table. In particular, the present invention provides a torque control device that can easily suppress resonance, focusing on giving an excitation signal to a multi-inertia resonance system.

FIG. 1 is a control block diagram of a motor torque control apparatus showing an embodiment of the present invention. 5 differs from FIG. 5 in that a resonance suppression table 21 for obtaining a torque excitation command value T ^* according to the excitation torque command Tvib ^* is provided as mechanical resonance suppression control means for suppressing resonance of the electric / mechanical system. It is in the point. The frequency component of the vibration torque command Tvib ^* is arbitrary, but in the present embodiment, it is a sine wave. Further, the torque command value can be generated by a resonance suppression calculation based on a system transfer function described later instead of the resonance suppression table.

Here, a method of realizing the resonance suppression table 21 will be described. The resonance suppression table 21 is identified as a system transfer function for each frequency component from the identification input “torque command value T ^* ” to the identification output “torque detection value T _det ”, and the reciprocal of the identification result for each frequency component is used. Configure. Since system identification is a general technique, details of the method are not particularly limited. For example, white noise is given to the torque command value T ^* as an identification input signal, and the shaft torque output signal (T _det ) at that time is observed and recorded. If the frequency transfer characteristic is obtained from the input / output recorded data, the system transfer characteristic (identification result) for each frequency component can be obtained. Instead of the shaft torque output signal (T _det ), it can be replaced with frame vibration detection using an acceleration sensor installed on the frame, rotation speed / position fluctuation detection using a rotation position sensor, or current pulsation detection using a current sensor. It is.

  The identification result is obtained on the basis of the following equation (9) corresponding to the equation (3), and is represented by a one-dimensional complex vector for each frequency component and tabulated. m represents a table element number representing a frequency component, and N represents the number of elements in the table. When actually used, only a one-dimensional complex vector corresponding to a desired excitation frequency component is extracted from the table and used.

N is an arbitrary natural number that determines the frequency resolution of the table. For example, when N = 1000 and the table is configured every 1 Hz, 1 to 1000 Hz can be expressed in increments of 1 Hz. P _Am : real part m-th element of system identification result, P _Bm : imaginary part m-th element of system identification result.

Above (9) P _Tm expressed in equation, it indicates a transfer characteristic from the torque command T ^* to a torque detection value T _det in the frequency component corresponding to the m-th element, the back-calculated values, i.e. the inverse characteristic P _Tm ^If a desired excitation torque command value Tvib ^* is input via ⁻¹ , a torque excitation command value T ^* in consideration of the system resonance characteristics can be generated. Since P _Tm ⁻¹ which is the reciprocal of the equation (9) is set data of the reciprocal of the one-dimensional complex vector, it can be easily calculated. Therefore, a table of system inverse characteristics P _Tm ⁻¹ calculated in advance is given to the resonance suppression table 21 of FIG. The frequency component extracted from the resonance suppression table is matched with the frequency component of the excitation torque command value. The transfer function for each excitation frequency is obtained from the detected shaft torque value T _det detected by the shaft torque meter 22.

  According to this embodiment, even if the excitation torque command coincides with the resonance point of the electric / mechanical system, the shaft torque waveform can be controlled safely and satisfactorily to a desired value without causing a dangerous torque resonance phenomenon. Can do. Further, the periodic disturbance suppression control means for suppressing the periodic disturbance of the torque output of the motor is configured to suppress simultaneously by the compensation current table 19 (or the resonance suppression calculation), so that the periodic disturbance suppression / target value is achieved. Both responses can be realized simultaneously.

  In general, the multi-inertia resonance system is a high-order complex system, and the controller is often required to perform complicated calculations. If this embodiment is used, since the inverse model characteristic is also represented by a one-dimensional complex vector, there is an advantage that the suppression control system can be designed relatively easily.

(Embodiment 2)
A configuration diagram of this embodiment is shown in FIG. 1 differs from FIG. 1 in that the resonance suppression table 23 is a torque command for each frequency component considering resonance suppression based on torque excitation command values Tvibl ^{* to} Tvibn ^* for a plurality of frequency components including DC components. The point is that the values T1 ^{* to} Tn ^* are obtained and superimposed to generate a torque command value T ^* .

P _Tm in the above equation (4) can be realized by superposing a plurality of frequency components. Therefore, in the present embodiment, the configuration of the first embodiment is made to correspond to torque excitation command values of a plurality of frequency components. The method for achieving both the torque ripple periodic disturbance suppression and the suppression of the resonance phenomenon of the electric / mechanical system by torque excitation is the same as the method described in the first embodiment.

As shown in FIG. 2, if the resonance suppression table is used as a multi-input multi-output and resonance suppression is performed independently, all resonance phenomena due to an excitation signal of a desired frequency component can be suppressed. Since the same resonance suppression table may be used at this time, it is not necessary to prepare a separate table for each frequency component. If the torque command values are overlapped after reading the table values corresponding to the torque excitation frequencies, the torque excitation command value T ^* considering the resonance suppression of the multi-order component can be generated.

  As described above, by using this embodiment, it is possible to generate an arbitrary torque waveform without causing a resonance phenomenon by superimposing excitation torques of a plurality of frequency components. In addition, torque ripple periodic disturbance can be suppressed at the same time.

(Embodiment 3)
When the motor is an interior permanent magnet synchronous motor (IPMSM), it is customary to effectively utilize the reluctance torque using the d-axis current. For example, the ratio between the d-axis current and the q-axis current is controlled so that the maximum torque can be obtained. In general, torque commands are converted into id and iq current command values using theoretical conversion formulas and adjustable conversion tables.

  In the embodiments described above, vector control is performed by converting a torque command including an excitation frequency component into id and iq current command values. That is, both id and iq current commands have an excitation frequency component. The IPMSM has a complicated torque generation mechanism depending on the load and the rotational speed because of its structure, and is likely to generate a torque error. When d-axis and q-axis currents are subjected to torque excitation for such a motor, there is a possibility that torque with a more complicated frequency component may be generated due to the influence of the above-described error and torque ripple characteristics.

  The simplest torque equation of IPMSM is expressed by the following equation (10). However, since the second term on the right side is multiplied by id and iq, if there is an excitation frequency component in both, a double frequency is generated. Also, since there is actually torque ripple. A simple approximate expression such as Expression (10) cannot accurately represent the frequency component included in the torque.

T: Torque, Pn: Number of pole pairs, Φ: Armature interlinkage magnetic flux by permanent magnet, Ld: d-axis inductance, Lq: q-axis inductance As described above, the torque generated by the motor is complicated due to the various causes described above. Frequency components are included. Therefore, in this embodiment, torque excitation is performed using only the q-axis current in order to reduce the adverse effects of the error and interference between the torque excitation frequencies of the d-axis and q-axis currents. FIG. 3 is a basic configuration diagram of the present embodiment, and a difference from FIG. 1 is that a shaft torque command separating unit 24 is added.

The shaft torque command separation unit 24 separates a direct current component To ^* and an excitation component Tvib ^* (a plurality of frequency components other than direct current) from an arbitrary waveform (that is, including a plurality of frequency components) shaft torque command value Tsh ^* . The separation method is arbitrary. For example, when generating a command value of an arbitrary waveform, the command value of the DC component and other frequency components may be separately commanded in advance, or even a mixed command value may be a high-pass filter (high-pass filter). ) Can be used to separate components other than direct current.

The DC component T ₀ ^* of the torque command separated as described above is converted into a d-axis current command value id * and a q-axis current command value (DC component) iqo ^* via the normal torque-id, iq current conversion unit 11. . On the other hand, the excitation component Tvib ^* uses the resonance suppression table 21A to suppress the resonance phenomenon due to the excitation torque command value. However, the resonance suppression table 21A used here is different from that of the first embodiment. In the present embodiment, in order to convert the excitation torque command into the q-axis current command value, the system identification result P _iq from the excitation current command value iqvib ^* to the shaft torque detection value Tdet shown in Equation (10) is used. The reciprocal P _iq ⁻¹ (inverse model) is given as a resonance suppression table.

P _Aiqm : m-th element of the real part of the system identification result, P _BAiqm : m-th element of the imaginary part of the system identification result Next, torque ripple T ^* and rotation are also different for torque ripple periodic disturbance suppression. The two-dimensional compensation current table 19A is configured with the q-axis current command value iqr and the rotation speed ω as input variables instead of the number ω. As shown in FIG. 3, iqr is a combination of the direct current value iqo ^* and the excitation current iqvib ^* . The generation of the compensation current is the same as that in the first or second embodiment, and the final q-axis current command value iq ^* is generated by superimposing the compensation current iqc ^* on the q-axis current command value iqr.

  According to this embodiment, by using torque excitation by the q-axis current command while separating from the DC torque component, torque waveform distortion and torque error due to interference of torque ripple and d-axis / q-axis current excitation can be reduced. It can be reduced relatively.

  Each embodiment shows a case of a control device that obtains torque excitation in the motor output, but it can be applied to a motor control device that generates a torque output of an arbitrary waveform in the motor to obtain an equivalent effect. it can.

DESCRIPTION OF SYMBOLS 11 Command value conversion part 12 Current vector control part 13 Motor 14 Load apparatus 15 Coordinate conversion part 16 Current sensor 17 Rotation phase / speed detection part 18 Rotation position sensor 19 Compensation current table 20 Compensation current generation part 21, 21A, 23, Resonance suppression Table 22 Shaft torque meter 24 Shaft torque command separator

Claims (7)

In a motor torque control device provided with a torque control circuit that outputs and controls a motor that drives the load device to a torque command value having an arbitrary waveform,
The resonance phenomenon of the electric / mechanical system due to the frequency component of the torque output of the motor is identified as a system transfer function for each frequency component from the torque command value to the detected torque value, and the reciprocal of the identification result for each frequency component is used. A motor torque control apparatus comprising mechanical resonance suppression control means for generating the torque command value using a resonance suppression table .   2. The motor torque control device according to claim 1, wherein the mechanical resonance suppression control unit expresses the system identification result by an approximate mathematical expression of a system characteristic. 3. The mechanical resonance suppression control means generates the torque command value in the resonance suppression table, and at the same time, generates the torque command by a periodic disturbance compensation current table or a periodic disturbance suppression calculation that suppresses periodic disturbance of motor torque output. 3. The motor torque control device according to claim 1, further comprising periodic disturbance suppression control means for correcting the value. When the mechanical resonance suppression control unit generates an arbitrary waveform torque output by superimposing an arbitrary waveform torque command value having a plurality of frequency components including a DC component, a plurality of the torque command values in parallel in a resonance suppression table The torque control apparatus for a motor according to any one of claims 1 to 3, wherein: The torque control circuit is configured to control the motor current by converting the torque command value into a d-axis q-axis current command value of a rotating coordinate system in vector control,
5. The motor torque control apparatus according to claim 1, wherein the periodic disturbance suppression control unit corrects a torque command value of only the q-axis current command value. 6.   The mechanical resonance suppression control means separates a torque command value having an arbitrary waveform having a plurality of frequency components including a DC component into a torque component other than a DC component and a torque component other than a DC component, and the DC component torque component is a d-axis q-axis. 6. The motor torque control device according to claim 1, wherein a torque component other than direct current is converted into a q-axis current command value in consideration of resonance suppression.   2. The periodic disturbance suppression control means suppresses a torque periodic disturbance by a torque resonance suppression table or a torque resonance suppression calculation using a q-axis current command value including a plurality of frequency components as an input. The torque control device for a motor according to any one of -6.

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