JP2838578B2 - Motor control device, disturbance load torque estimation device - Google Patents

Description

The present invention relates to a motor control device that controls the speed and torque of a motor with high accuracy, and is particularly suitable for a servo motor that constitutes an actuator of an industrial robot or the like. About things.

[Conventional technology]

In motor speed control, generally, a motor current is controlled in accordance with a difference between a detected speed of the motor and a command speed, thereby controlling a generated torque of the motor.
However, in a field where high-precision speed control is required, it is necessary not to be affected by load disturbance (torque) acting on the motor. Therefore, conventionally, a disturbance load torque acting on a motor is obtained by estimation, and the disturbance load torque estimated value is added to a torque command value of a speed control system or its equivalent value (for example, a current command value) to obtain a load disturbance component. To compensate for speed fluctuations. As a method of estimating such disturbance load torque,
For example, two methods are described in "Design of a Robust Servo System Based on Parameterization of a Two-Degree-of-Freedom Control System" (February 22, 1989), a document of the Institute of Electrical Engineers of Japan and the Institute of Industrial Power Electrical Engineers of Japan.

In the first method, an acceleration (deceleration) torque is obtained from a moment of inertia of a motion system including a motor and a load and a differential value (acceleration) of the motor speed, and the obtained torque is subtracted from a generated torque of the motor to obtain an estimated value of a disturbance load torque. It is a method of seeking. That is, the motor generated torque τ is a disturbance load torque τ _d ,
Assuming that the motor speed is ω and the moment of inertia of the motion system is J, it can be expressed by the following equation (1). Therefore, by the inverse system, the estimated value of the disturbance load torque is expressed by the following equation (2). Can be obtained. Is a simulated value of the moment of inertia determined for use in the control law.

According to the first method, the differential value is obtained by detecting the speed ω, and the disturbance load torque is estimated from the differential value and the generated torque, so that a disturbance load torque estimated value without control delay can be obtained. There is an advantage.

On the other hand, the second method is a so-called state observer. It has a forward model of the dynamic characteristics of the motion system including the motor and the load (a model in which the motor generated torque τ is input and the motor speed ω is output), and the detected value of the motor generated torque is input to this model. , The disturbance load torque estimated value based on the difference between the motor speed output from the model and the detected value. And the obtained disturbance load torque estimated value Is negatively fed back to the input of the model. The disturbance load torque can be estimated with a time constant determined by the gain of the negative feedback (observer gain).

[Problems to be solved by the invention]

However, according to the conventional disturbance load torque estimation method,
There are the following problems.

First, according to the first method, since the differential value of the speed ω is obtained by calculation, there is a problem that the control system is easily affected by noise in a region where a fast torque fluctuation occurs, and the control system is likely to be unstable. Further, as is apparent from Equation (2), since the simulation value of the moment of inertia is included, when the moment of inertia of the actual motion system changes with time (for example, expansion and contraction of the robot arm, etc.). The estimation accuracy decreases. Further, in the case of a high-order mass system, there is a problem that the moment of inertia cannot be easily simulated.

In this regard, since the method using the second state observer has a negative feedback loop, it can cope with the above-described fluctuation of the moment of inertia. However, since the estimation is performed asymptotically using negative feedback, there is a time delay in the estimation. Although the time required for the estimation can be shortened by the magnitude of the observer gain, there is a problem that the estimation speed becomes slow under conditions where the observer gain cannot be set sufficiently large due to the calculation cycle.

SUMMARY OF THE INVENTION An object of the present invention is to provide a disturbance load torque estimating apparatus which can cope with fluctuations of parameters such as a moment of inertia and which can quickly and accurately estimate a disturbance load torque.

Another object of the present invention is to provide a motor control device or a robot control system including the disturbance load torque estimation device as described above and capable of performing highly responsive and highly accurate speed control.

[Means for solving the problem]

In order to achieve the first object, the disturbance load torque estimating apparatus of the present invention has first and second disturbance load torque estimating means that receive the detected values of the generated torque and the speed of the motor as inputs. The first disturbance load torque estimating means obtains one of a differential value of the motor speed detection value and an approximate differential value including a first-order lag element, and converts the differential value or the approximate differential value into a motor shaft. And a moment of inertia of a motion system including a load, and a value obtained thereby is subtracted from the detected torque to obtain a first disturbance load torque estimation value. The second disturbance load torque estimation means Has a forward model of the speed characteristic of the motion system with respect to the generated torque of the motor, inputs the generated torque detection value to this model, and is proportional to the difference between the model output and the motor speed detection value. Is to calculate a second disturbance load torque estimated value by performing one of the processes of proportional integration, and the sum of the first and second disturbance load torque estimated values is used as a disturbance load torque estimated value, This disturbance load torque estimated value is negatively fed back to the input of the model.

In order to achieve the second object, the motor control device or the robot control system according to the present invention uses the disturbance load torque estimating device, and performs speed control by negatively feeding back the disturbance load torque estimation value estimated by the disturbance control torque estimation device. Alternatively, torque control is performed.

[Action]

With such a configuration, according to the present invention, the above object is achieved by the following operations.

First, since the first disturbance load torque estimating means basically measures the disturbance load torque by differentiating the speed, it is possible to perform the estimation without delay. However, since the gain cannot be increased so much to remove noise in a high frequency region, the estimated value constantly includes an offset amount. On the other hand, the second disturbance load torque estimating means is a state observer, so that the above-described offset can be removed, but the time constant is delayed according to the observer gain. In this regard, the present invention is a combination of the above two advantages, and the differential gain and the observer gain of the first and second disturbance load torque estimating means are adjusted in accordance with the required control responsiveness and accuracy. By adjusting the ratio, it is possible to estimate the disturbance load torque without delay and without offset.

Further, by performing the torque compensation of the motor control using the disturbance load torque estimating means of the present invention, a highly responsive and high-accuracy motor control can be realized.

The model output of the disturbance load torque estimating means is:
Since this model output is equivalent to the instantaneous speed of the motor, if this model output is used as a motor speed estimation value for motor speed control, etc., the time detection value of analog speed detection means such as a tachogenerator or position detection value of a decoder etc. As a result, it is possible to obtain a highly accurate detection value with excellent responsiveness, compared to the motor speed detection value obtained by the speed detection means for detecting the speed.

〔Example〕

 Hereinafter, the present invention will be described using examples.

FIG. 1 is a block diagram showing a configuration in which the present invention is applied to a motor speed control device. That is, the motor 1
Is a speed control device that drives the mechanical load 2 at a desired speed, and the motor 1 may be either an AC motor or a DC motor. The mechanical load 2 may be an industrial robot,
A servo device or the like is applied. The motor 1 is driven by a motor driving unit 3 including a power conversion device such as an inverter or a converter. The motor driving means 3 controls the electric power supplied to the motor 1 so as to generate a predetermined torque and control the motor speed. The speed command value ω _r of the motor 1 is provided to the speed control means 4 from a higher-level control means (not shown) or the like. The speed control means 4 generates a torque command value (or a current command value) τ _r * corresponding to the speed command value ω _r and inputs the generated torque command value to the motor control means 3 via the adder 5. on the other hand,
The speed of the motor 1 is detected by the speed detecting means 6, and the detected value ω is negatively fed back to the speed control means 4 so that the difference between the speed command value ω _r and the detected speed value ω is zero. τ _r * is corrected. Further, since the current of the motor 1 can be considered to be proportional to the motor generated torque, the motor current is detected by the motor current detecting means 7 and is used as a generated torque detection value τ.
A negative feedback, so as to zero the difference between the torque command value tau _r generated torque detection value tau, the motor current is controlled.

Here, the compensation part of the torque command value τ _r by the disturbance load torque τ _d according to the present invention will be described. The disturbance load torque estimating device 8 receives the motor speed detection value ω and the generated torque detection value τ as inputs, and performs a disturbance load torque estimation value by a process described later. Ask for. The estimated disturbance load torque estimated value Is input to the adder 5 as a torque compensation value τ _f through the compensation means 9 and is added to the torque command value τ _r *. The compensation means 9 receives the input disturbance load torque estimated value. And to achieve desired speed control characteristics.

One embodiment of the detailed control block diagram of the disturbance load torque estimating means 8 is shown in FIG. FIG. 2 shows the entire components of FIG. 1 using transfer functions, and among the reference numerals assigned to the blocks, the same components as those in FIG. 1 correspond to the same components. In the figure, S is an operator representing differentiation, and the transfer function with the speed control means is H (S),
The transfer function of the motor driving means 3 is represented by P (S), and the transfer function of the motion system including the motor and the load is represented by block 10.
The transfer function of the compensator 9 is Q (S). Disturbance load torque estimating device 5, the block 11 and the adder 12 and the first disturbance load torque estimating means consisting of coefficient multiplier 13 for multiplying the gain K _1, the adder 14 and the block 15 and the adder 16 and the observer gain K _{A second} disturbance load torque estimating means comprising a coefficient multiplier 17 multiplied by ₂ and an adder 18.

The first disturbance load torque estimating means is given by the following equation (3).
First disturbance load torque estimated value Block 11 differentiates the speed detection value ω,
This is multiplied by a simulated value (constant) of the inertia moment in terms of the motor axis of the motion system to obtain a torque required for acceleration (or deceleration). This is subtracted from the generated torque τ by an adder 12, Multiply by the gain K ₁ at Ask for.

On the other hand, the second disturbance load torque estimation means is a so-called state observer. As shown in the following equation (4), the first disturbance load torque estimation value τ _d1 The second value corresponding to the difference from the disturbance load torque τ _d to be estimated
The disturbance load torque tau _d2 is to estimate by calculation.

Substituting the relationship of equation (4) into the characteristic equation (1) of the motion system, Is obtained. In such a system, as a method for estimating the second component τ _d2 , for example, the literature (Iwai et al., 2 authors,
As described in "Observer", pp.206-213, Corona, 1988), an expanded system is created by adding a dynamic characteristic equation of unknown disturbance (here, τ _d2 ) to the original characteristic equation, and using this. Thus, a method of configuring a state observer for an unknown disturbance is known. Here, a state where the change of τ _d2 can be ignored with respect to the step response, that is, When the state equation is made as follows, it can be expressed as the following equations (7) and (8).

In other words, when the characteristics of the system are expressed by the following equation (9), The variables x, u, y and the coefficients A, B, C in the equation (9) correspond to the following.

x = [τ _d2 , ω] ^t , (t represents a transposed matrix) Here, since the motor speed ω can be detected from the state variable x = [τ _d2 , ω] ^t , the minimum dimension observer that estimates only the load torque τ _d2 can be configured as in the following equation (10).

Now Then, the coefficient matrices D, E, M, P, and V of the minimum-dimensional observer in Expression (10) are given as in the following Expression (11).

Here, L is an observer gain. By substituting the relations of equations (7) and (8) into equation (11), the following equation (12) is obtained.

Here, is a simulated value (constant) of the total inertia moment value of the drive system, and It is. From this, the estimated value of the load torque Rearranges equation (12) Is obtained as follows. To organize this relationship, when represented by K ₂ the observer gain L as a second observer gain,
The second load torque estimating means in FIG. 2 is obtained.

That is, negative feedback is provided from the detected torque value τ of the motor. Is subtracted by an adder 14, and this value is led to a block 15 simulating a motion system, integrated at 1 / s to obtain a value corresponding to the speed, and the difference between this and the detected speed ω is calculated by an adder 14. determined at 16, is multiplied by the observer gain K ₂ to the difference, the second disturbance load torque estimated value Ask for. This is added to the first disturbance load torque estimated value by the adder 18. To the final disturbance load torque estimate Is output to the compensation means 9 and the adder 14
Negative feedback to.

Here it will be described the characteristics of the disturbance load torque estimating device 8 having two gain K ₁ and K ₂ described above as adjustable parameter. Now, the estimated value for the disturbance load torque τ _d Are obtained under the condition of τ = 0. In this condition, Ω and ω Erase Ask for a relationship. As a result, the following equation (18) is obtained.

Here, Td is the time constant of the disturbance load torque estimated determined by the second observer gain K _2, is given by the following equation (19).

Here, the synergistic action of the first and second disturbance load torque estimation means will be described. First, in the disturbance load torque estimating device 8 shown in FIG. 2, when K ₂ = 0, only the first disturbance load torque estimating means based on velocity differentiation is used. Conversely, when K ₁ = 0, the second disturbance due to the state observer is used. Only the load torque estimating means is provided. That is, the above equation (18) becomes the following equation (20) when K ₂ = 0, and the following equation (21) when K ₁ = 0.

The comparison of the characteristics of the disturbance load torque estimation shown in the above equations (18), (20) and (21) will be described with reference to FIG. First, according to the first disturbance load torque estimation of the equation (20), K ₁
By setting = 1, the disturbance load torque can be estimated without time delay. However, as described above, in order to avoid the influence of high-frequency noise, K ₁ must be limited to <1. Therefore, the estimated characteristics of the disturbance load torque τ _d with respect to the step change are shown in FIG. Become like That is, for a change in the disturbance load torque τ _d , Although follow rapidly changing, the constant comes to have an offset amount to the actual value tau _d. In contrast, according to the second disturbance load torque estimating equation (21), as shown in FIG. 3 (b), it can be estimated without offset constant Td time corresponding to observer gain K _2. However, an attempt to shorten the estimation time, but it is necessary to increase the K _2, since the closed loop observer becomes unstable by increasing the K _2, must be limited to below a certain value.
Therefore, as shown in FIG. 3B, the offset amount can be reduced as compared with the first disturbance load torque estimation, but the time required for the estimation (rise time) is delayed, and the high response of the motor control is impaired. It is. On the other hand, according to the embodiment of FIG. 2 in which the first and second disturbance load torques are combined, as shown in FIG. Disturbance load torque estimate without quantity As a result, high-speed and high-accuracy speed control can be realized. The gains K ₁ and K ₂ are adjusted by the motor 1
This is performed depending on which of the first and second disturbance load torque estimating means is weighted in accordance with the characteristics of the mechanical load 2 and the required speed control.

Disturbance load torque estimated value obtained as described above Is fed back to the speed control system via the compensation means 9 and is controlled so as to generate a torque excluding the influence of the disturbance load torque. As the transfer function Q (S) of the compensator 9, a normal first-order lag filter represented by the following equation (22) is used.

The time constant _{Tf in} equation (22) is set to be smaller than the response frequency of the speed control system.

FIG. 4 shows another embodiment of the disturbance load torque estimating apparatus according to the present invention. This embodiment differs from the Figure 2 embodiment, in addition to the feedback loop of the second disturbance load torque estimating means observer gain K _2, block 19 integral element
The point is that 1 / T ₂ S is provided and proportional integration is performed. According to this, since the order of the disturbance load torque can be increased, there is an effect that the disturbance load torque in a wider band can be estimated with good response.

That is, the characteristics of the disturbance load torque estimation of the embodiment of FIG. 4 are obtained by replacing the expression (16) in the above-mentioned expressions (14) to (17) with the following expression (22).

Regarding this, τ _d and Is obtained, the following equation (24) is obtained.

here, As is apparent from this relational expression, when K ₁ = 0 is substituted into the equation (24) when the gain K _{1 of} the first disturbance load torque estimating means is zero, the load torque estimating characteristic by the ordinary secondary system is obtained. Show. On the other hand, by adding the first load torque estimating means, the quadratic term of S appears in the numerator of equation (24). This characteristic indicates a second-order phase lead / lag characteristic, and the characteristic can be varied depending on whether K1 is larger or smaller than ₁ as in the case of Expression (18). Thus, the fourth
According to the method of the embodiment shown in the figure, the order of disturbance load torque estimation can be increased, so that disturbance load torque over a wider band can be estimated with good response.

FIG. 5 is a block diagram of another embodiment of the disturbance load torque estimating device according to the present invention. This embodiment differs from the embodiment of FIG. 2 in that an approximation differential system is obtained by adding a first-order lag element to the differentiation of the first disturbance load torque estimating means.
According to this, there is an effect that the instantaneous fluctuation of the disturbance load torque can be suppressed, and more stable estimation can be performed.

That is, the block 11 in FIG. 2 is replaced with a block 21 having a transfer function represented by the following equation (25).

Here, Te is a first-order lag time constant in the approximate differentiation. The disturbance load torque estimation characteristic at this time is given by equation (14),
From (25), (16), and (17), the following equation (26) is obtained.

Here, T _d = / K ₂ . As described above, there is an advantage that the band of disturbance load torque estimation can be suppressed by using the approximate derivative instead of the speed derivative, and more stable load torque estimation can be performed. In addition, this method uses the second method as shown in FIG.
The same applies to the case where the observer gain portion of the load torque estimating means is compensated for proportional integral.

Further, in each of the above embodiments, the case where the speed control of the motor is compensated by the disturbance load torque estimated value has been described. However, the present invention is not limited to this. The same can be applied to the case where the speed control system is compensated by the disturbance load torque estimated value.

Next, an embodiment in which the estimation method of the disturbance load torque estimation device according to the present invention is applied to estimation of the instantaneous speed of a motor will be described.

In the embodiment shown in FIG. 2, the second load torque estimating means waits for a forward model representing a characteristic of the generated torque τ to the motor speed ω. That is, the output of the block 15 of the integral element of the second load torque estimation is the speed estimation value. Is output. Therefore, the estimated characteristic of the disturbance load torque is (1
8) Actual speed ω and estimated speed, given by equation The relationship is Given by If there is a dead time in detecting the actual speed ω, the speed estimation value Is a speed estimation value that compensates for the dead time of detection.

Speed estimate obtained as above Since there is no delay corresponding to the instantaneous speed of the motor 1, if this is fed back to the speed control means 4 instead of the detected speed value ω, the responsiveness of the control can be increased. In other words, the speed detection value ω detected by the speed detection means 6 of an analog system such as a tachogenerator has a problem that a delay is usually caused by a filter for noise removal, and this affects a control delay of the speed control system. According to the example, such a problem can be solved. In addition, even when using the speed detecting means 6 which uses a position detecting means such as an encoder or a resolver and detects the speed by the time differentiation of the rotational position, the averaging error and the time delay caused by the time differentiation are reduced. Then, there is a problem similar to that in the case of the above-mentioned tachogenesis or the like. In addition, since the disturbance load torque estimation is based on a combination of the state observer and the velocity derivative, the velocity estimation characteristic can have a zero point as shown in equation (27). can get.

In the above description of the embodiment, the motor generated torque τ
Is detected as a load torque estimator, the relationship between the torque command value τ _r and the generated torque τ is approximated by a transfer function (s), and τ ′ = (s) τ _r (28) And load torque estimation can be performed using τ ′. Note that (s) can be approximated as “1” when the response of the torque control system (current control system) is sufficiently fast, and can be approximated as a first-order delay when there is a delay. That is, (s) = 1 (29) Can be approximated by Here, T _a is the time constant of the current control response.

Further, in each of the above embodiments, the case where the control system is a continuous system is described. However, the case where the control system is discretely executed by a microcomputer or the like can be similarly configured by converting the integral and differential elements into a discrete time system. .

Further, in the above description, a case where a speed detector is used as a speed detector such as a tachometer, which detects a speed as a continuous amount, has been described.However, a position detector such as an encoder or a resolver is used, and time differentiation of the position is performed. The same configuration can be applied to the case of detecting the speed.

〔The invention's effect〕

As described above, the present invention has the following effects.

First, according to the disturbance load torque estimating device of the present invention, first disturbance load torque estimating means capable of performing estimation without delay for estimating the disturbance load torque by basically differentiating the speed, and removing the offset. Since the advantages of both of the second disturbance load torque estimating means by the possible state observer are combined, the differential gains of the first and second disturbance load torque estimating means are adjusted in accordance with the required control responsiveness and accuracy. And observer gain, the disturbance load torque without delay and without offset can be estimated.

Further, by performing torque compensation for motor position control and speed control using the disturbance load torque estimation means of the present invention,
Speed fluctuation due to disturbance load can be compensated with good response,
Stable and highly accurate motor control can be realized with respect to impact loads, shaft vibrations of mechanical systems, fluctuations of inertia moments of motion systems, and the like.

The model output of the disturbance load torque estimating means is:
Since this model output is equivalent to the instantaneous speed of the motor, this model output is used as an estimated value of the motor speed to control the speed of the motor. It is possible to obtain a highly accurate detection value that is more responsive than the motor speed detection value obtained by the speed detection means that detects the speed by differentiating the value with time, and as a result, it is possible to realize stable speed control over a wide range. .

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a motor speed control device according to an embodiment to which a disturbance load torque estimating device of the present invention is applied.
Fig. 3 is a detailed block diagram of the embodiment of Fig. 1, Fig. 3 is a diagram for explaining the effect of the embodiment of Fig. 1, and Figs. 4 and 5 are other embodiments of the disturbance load torque estimating apparatus. FIG. 3 is a block diagram of an example. 1 ... motor, 2 ... mechanical load, 3 ... motor drive means, 4 ... speed control means, 6 ... speed detection means, 8 ...
Disturbance load torque estimating device, 9 ... compensating means.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H02P 5/00

Claims (6)

(57) [Claims] 1. Speed detecting means for detecting a speed of a motor;
Speed control means for outputting a control command value corresponding to a torque command value of the motor according to a difference between the detected speed value and a given speed command value of the motor; and driving the motor based on the control command value. Drive control means, a torque detection means for detecting a physical quantity corresponding to the generated torque of the motor as a generated torque, and a disturbance load torque for obtaining an estimated value of a disturbance load torque of the motor from the detected torque value and the speed detection value. Estimating means for correcting the control command value of the motor based on the disturbance load torque estimated value obtained by the motor control apparatus. Either the differential value of the value or the approximate differential value including the first-order lag element is obtained, and the motor value converted to the motor shaft is converted to this differential value or the approximate differential value. A first disturbance load torque estimating means for multiplying a moment of inertia of a motion system including a load and a load, and subtracting the value obtained from the generated torque detection value to obtain a first disturbance load torque estimation value; It has a forward model that outputs the speed of the motion system with respect to the generated torque, and inputs the generated torque detection value to this model, and either proportional or proportional integration is performed based on the difference between the model output speed and the motor speed detection value. And a second disturbance load torque estimating means for obtaining a second disturbance load torque estimated value by performing one of the processes, wherein the sum of the first and second disturbance load torque estimated values is used as a disturbance load torque estimated value. And a negative feedback to the input of the model. 2. A speed control means for outputting a control command value corresponding to a torque command value of the motor according to a difference between a detected speed value of the motor and a given speed command value of the motor; And a drive control means for driving the motor based on the calculated value. One of a differential value of the motor speed detection value and an approximate differential value including a first-order lag element is obtained. A first disturbance load for obtaining a first disturbance load torque estimation value by multiplying the differential value by a moment of inertia of a motion system including a motor and a load converted into a motor shaft, and subtracting the obtained value from a detected torque detection value; A torque estimating means, and a forward model having an output of the speed of the motion system with respect to the generated torque of the motor, and inputting the generated torque detection value to this model;
A second disturbance load torque estimating means for performing one of a process of proportionality and a proportional integral on the difference between the model output and the motor speed detection value to obtain a second disturbance load torque estimated value; Motor speed estimating means for negatively feeding back the sum of the first and second disturbance load torque estimated values to the input of the model and using the output of the model as the estimated speed of the motor; A motor control device, wherein the speed control value is input to the speed control means instead of the speed detection value. 3. A speed detecting means for detecting a speed of a motor;
Speed control means for outputting a control command value corresponding to a torque command value of the motor according to a difference between the detected speed value and a given speed command value of the motor; and driving the motor based on the control command value. Drive control means, a torque detection means for detecting a physical quantity corresponding to the generated torque of the motor as a generated torque, and a disturbance load torque for obtaining an estimated value of a disturbance load torque of the motor from the detected torque value and the speed detection value. Estimating means for correcting the control command value of the motor based on the disturbance load torque estimated value obtained by the motor control apparatus. Either the differential value of the value or the approximate differential value including the first-order lag element is obtained, and the motor value converted to the motor shaft is converted to this differential value or the approximate differential value. A first disturbance load torque estimating means for multiplying a moment of inertia of a motion system including a load and a load, and subtracting the value obtained from the generated torque detection value to obtain a first disturbance load torque estimation value; It has a forward model that outputs the speed of the motion system with respect to the generated torque, and inputs the detected torque value to this model, and either one of proportional or proportional integral with the difference between the model output and the motor speed detected value. And a second disturbance load torque estimating means for obtaining a second disturbance load torque estimation value, and the sum of the first and second disturbance load torque estimation values is used as a disturbance load torque estimation value. A negative feedback to the input of the model, and the model output is input to the speed control means instead of the detected speed value of the motor. The control device. 4. A control command value corresponding to a torque command value output from said speed control means, instead of a detected torque value input to said disturbance load torque estimation means. 4. The motor control device according to any one of claims 2 and 3. 5. A motor vehicle comprising: first and second disturbance load torque estimating means for inputting detected values of a generated torque and a speed of a motor, respectively; Either the differential value of the value or the approximate differential value including the first-order lag element is obtained, and this differential value or the approximate differential value is multiplied by the moment of inertia of the motor and the motor including the load converted into the motor shaft, and the resulting value is obtained. A first disturbance load torque estimation value is obtained by subtracting the obtained value from the generated torque detection value. The second disturbance load torque estimation means is configured to calculate a speed characteristic of the motion system with respect to the generated torque of the motor. A forward disturbance model, the generated torque detection value is input to the model, and either one of processing proportional or proportional to the difference between the model output and the motor speed detection value is performed to perform the second disturbance load. A torque estimation value is obtained. The sum of the first and second disturbance load torque estimation values is used as a disturbance load torque estimation value, and the disturbance load torque estimation value is negatively fed back to the input of the model. Disturbance load torque estimation device. 6. A motor vehicle comprising: first and second disturbance load torque estimating means for inputting detected values of a generated torque and a speed of a motor, respectively; Either the differential value of the value or the approximate differential value including the first-order lag element is obtained, and this differential value or the approximate differential value is multiplied by the moment of inertia of the motor and the motor including the load converted into the motor shaft, and the resulting value is obtained. A first disturbance load torque estimation value is obtained by subtracting the obtained value from the generated torque detection value. The second disturbance load torque estimation means is configured to calculate a speed characteristic of the motion system with respect to the generated torque of the motor. A forward disturbance model, the generated torque detection value is input to the model, and either one of processing proportional or proportional to the difference between the model output and the motor speed detection value is performed to perform the second disturbance load. A torque estimation value is obtained. The sum of the first and second disturbance load torque estimation values is used as a disturbance load torque estimation value, and the disturbance load torque estimation value is negatively fed back to the input of the model. A motor speed estimating device for outputting an output speed of the model as an estimated value of an instantaneous speed of the motor.