JP3252695B2 - Motor control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor controller for stably controlling a machine tool having a backlash.

[0002]

2. Description of the Related Art FIG. 10 shows a block diagram of a conventional motor control device. The control of the electric motor 1 to which the load 9 is added is performed by an integrator 71 based on a position deviation between an actual position detected by an encoder (position detection unit) 8 by a position control unit 7 and a position command, and a gain KP is calculated. The speed command is calculated by multiplying by the amplifier 72.

[0003] The actual speed of the electric motor 1 is determined by a speed detecting means.
4) Speed control based on speed deviation from speed command
Means 2 calculates a current command. At this time, the speed control means 2
Then, the speed deviation is calculated using the proportional term 2 having the speed proportional gain KSP.
A current command is calculated by adding an integral term 22 having a speed integral gain KSI and a differential term 23 having a speed differential gain KSD. Further, the torque of the motor 1 is controlled by the current controller 3 based on the current command and the motor current detected by the current detecting means 5.

However, a load 9 in an actual machine tool includes a gear in a power system, and there is play between the gears.
For this reason, when the electric motor 1 is rotating, the inertia moment of the load is generated at the shaft end of the electric motor 1 because the gears are engaged. However, when the electric motor 1 is almost stopped, it is not known which of the inertia moment of no load and the load is generated at the shaft end of the electric motor 1, so that the moment of inertia generated at the end of the electric motor 1 greatly changes.

At this time, the response frequency fc in the speed control system is
Are the moment of inertia JL of the load 9, the moment of inertia JM of the electric motor 1, the speed proportional gain KSP, and the speed integral gain K
SI, speed differential gain KSD, proportional constant g, P1, P2
Then, empirically, the relationship of equation (1)

[0006]

(Equation 1)

[0007] Even if the optimum speed gain is set for the inertia moment JL of the load, there is play in the gears.
In some cases, the moment of inertia JL becomes small. At that time, the response frequency of the speed control system becomes high, causing hunting of the electric motor 1.

In order to prevent such hunting of the electric motor 1, a conventional electric motor control device employs a motor 1 in advance.
A speed gain lower than the optimum speed gain for the inertia moment (JM + JL) between the motor and the load 9 is set to lower the response frequency of the speed control system or to reduce the inertia moment J of the electric motor 1.
M is increased, and the ratio of the inertia moment JL of the load to the inertia moment JM of the electric motor 1 is decreased to suppress the inertia moment fluctuation, or in the case of a small inertia moment fluctuation, Japanese Unexamined Patent Publication No. 63-214372. As described in the publication, hunting is prevented by adjusting the speed integral gain KSI when the position deviation value is equal to or less than the reference value.

[0009]

As described above, in the conventional motor control device shown in FIG. 10, a speed gain lower than the optimum speed gain for the moment of inertia (JM + JL) between the motor 1 and the load 9 is set in advance. However, since the response frequency fc of the speed control system is lowered, high-accuracy position control cannot be realized. In addition, the moment of inertia JM of the motor 1 is increased, and the ratio of the moment of inertia JL of the load to the moment of inertia JM of the motor 1 is reduced to suppress the fluctuation of the moment of inertia. Was exerted. further,
When the position deviation value is equal to or less than the reference value, the speed integral gain KS
Only by adjusting I, there is a limit to the fluctuation of the inertia moment which can be dealt with. In addition, since the determination is made based on the position deviation value, the speed integral gain KSI may be changed even when the electric motor 1 is rotating. The performance was adversely affected.

The present invention has been made to solve the above-described problem, and has an advantage that the acceleration / deceleration time is lengthened even in a machine tool in which the moment of inertia generated at the shaft end of the electric motor 1 largely changes due to the play of the gear. To achieve high-accuracy position control by always keeping the response frequency of the speed control system constant without setting a speed gain smaller than the optimum speed gain for the moment of inertia generated at the shaft end of the motor 1. With the goal.

[0011]

According to a first aspect of the present invention, there is provided an electric motor, comprising:
Current control means for controlling the torque of the motor;
A current detecting means for detecting a current flowing through the motor;
Speed detecting means for detecting the speed of the motive;
From the current value and the speed value obtained from the step and the speed detecting means.
Estimate the moment of inertia of the load added to the motor
Means for estimating the moment of inertia for
The moment of inertia estimated by the moment of inertia estimating means.
Speed by changing to the speed gain calculated from the
Those having a speed control means for.

In addition, in the invention according to claim 2,
Is the load added to the motor when the speed falls below the reference speed.
The moment of inertia of the
Speed by changing to the speed gain calculated from the
2. A switch determining means for enabling the switching operation.
The motor control device is provided.

In the invention according to claim 3 ,
Position detecting means for detecting the position of the electric motor;
From the position detected by the means and the position command
Position control means to control the position of
Becomes, the moment of inertia of the load added to the motor
Estimated from the moment and calculated from the moment of inertia by the speed control means.
Effective to control speed by changing to speed gain
2. The electric motor control according to claim 1, further comprising: a switching determination unit that sets
It has a control device.

Further, in the invention according to claim 4 ,
Position detecting means for detecting the position of the electric motor;
From the position detected by the means and the position command
Control means for controlling the position of the motor, and the position and position of the motor
If the integrated value of the deviation from the command falls below the standard,
Estimate the moment of inertia of the applied load and control the speed.
To the speed gain calculated from the moment of inertia
Switching determination means for enabling the control of the speed
The motor control device according to claim 1, further comprising:
is there.

In the invention according to claim 5 , the electric power
Position detecting means for detecting the position of the motive;
From the position detected by the step and the position command,
Position control means for controlling the position, and the position and position finger of the electric motor
Both the integral value of deviation from the command and the position command are below the standard
And the moment of inertia of the load applied to the motor.
And calculate from the moment of inertia with the speed control means.
Enable speed control by changing to speed gain
2. The motor control device according to claim 1, further comprising: a switching determination unit.
It is provided with.

Further, in the invention according to claim 6,
Is a motor and a position detecting means for detecting the position of the motor.
Step, position and position finger detected by the position detection means
And position control means for controlling the position of the electric motor from the command.
Speed detecting means for detecting a speed of the electric motor;
Speed detected by the detection means and output from the position control means
The speed of the motor is controlled by the speed command
Command, the moment of inertia with no load
Electric motor equipped with speed control means for changing to an appropriate speed gain
Machine control device.

Further, in the invention according to claim 7 ,
Electric motor and position detecting means for detecting the position of the electric motor
And a position detected by the position detecting means and a position command.
Position control means for controlling the position of the motor from
Speed detecting means for detecting the speed of the electric motor;
Speed detected by the output means and the output
The speed of the motor is controlled by the speed command
When the integrated value of the deviation between
To a speed gain suitable for the moment of inertia in the absence of
The present invention provides a motor control device provided with a speed control means .

Further, in the invention according to claim 8 ,
Electric motor and position detecting means for detecting the position of the electric motor
And a position detected by the position detecting means and a position command.
A position control means for controlling the position of the electric motor from
Speed detecting means for detecting the speed of the electric motor;
Speed detected by the output means and the output
The speed of the motor is controlled by the speed command
Both the integral value of the deviation between the position command and the position command are below the reference
Is suitable for the moment of inertia without load.
Motor control having speed control means for changing to speed gain
Control device .

[0019]

According to the configuration of the present invention, the moment of inertia between a motor and a load can be estimated, and the response frequency of a constant speed control system can be constantly determined using the estimated moment of inertia. It has the function of setting the obtained speed gain.

According to the second aspect of the invention, the estimation of the moment of inertia is switched between valid and invalid in the judgment of the speed command, and by using the estimated moment of inertia, the response frequency of the speed control system is always constant. Has the effect of setting the speed gain that can be obtained.

According to the third aspect of the present invention, the estimation of the inertia moment is switched between valid and invalid in the determination of the position command, and the estimated inertia moment is used, so that the response frequency of the speed control system is always constant. Has the effect of setting the speed gain that can be obtained.

According to the fourth aspect of the present invention, the estimation of the moment of inertia is switched between valid and invalid in the judgment of the integral value of the position deviation value, and the estimated moment of inertia is used, so that constant speed control is always performed. It has the effect of setting the speed gain at which the response frequency of the system is obtained.

According to the configuration of the present invention, the estimation of the moment of inertia is switched between valid and invalid by judging both the integrated value of the position deviation value and the position command, and the estimated moment of inertia is always used by using the estimated moment of inertia. This has an effect of setting a speed gain that can obtain a constant response frequency of the speed control system.

Further, according to the invention of the sixth aspect, by switching the speed gain based on the determination of the position command, there is an operation of setting the speed gain at which a constant response frequency of the speed control system can be obtained.

Further, according to the configuration of the invention according to claim 7, the speed gain is switched by judging the integral value of the position deviation value, so that the speed gain that can obtain a constant response frequency of the speed control system is set. .

In the invention according to the eighth aspect, the speed gain is set by switching the speed gain by judging both the integrated value of the position deviation value and the position command, thereby setting the speed gain at which a constant response frequency of the speed control system can be obtained. It has the effect of doing.

Embodiment 1 Hereinafter, Embodiment 1 of the present invention will be described with reference to FIG.

The speed control of the motor 1 to which the load 9 is added is performed by detecting the actual speed of the motor 1 by the speed detecting means 4.
The current command is calculated by the speed control means 2 based on the speed deviation from the speed command. At this time, the speed control means 2 calculates a current command by adding the speed deviation to the proportional term 21 having the speed proportional gain KSP, the integral term 22 having the speed integral gain KSI, and the differential term 23 having the speed differential gain KSD. ing. Further, the torque of the motor 1 is controlled by the current control means 3 based on the current command and the motor current detected by the current detection means 5.

However, the load 9 in the actual machine tool includes a gear in the power system, and there is play between the gears.
For this reason, when the electric motor 1 is rotating, the inertia moment of the load is generated at the shaft end of the electric motor 1 because the gears are engaged. However, when the motor 1 is almost stopped, it is not known whether the inertia moment of the no-load or the load occurs at the shaft end of the motor 1, so that the inertia moment generated at the shaft end of the motor 1 changes greatly.

At this time, the response frequency fc in the speed control system
Are the moment of inertia JL of the load 9, the moment of inertia JM of the electric motor 1, the speed proportional gain KSP, and the speed integral gain K
SI, speed differential gain KSD, proportional constant g, P1, P2
Then, empirically, there is the relationship shown in the equation (1).

The moment of inertia generated at the shaft end of the motor 1 is estimated by the moment of inertia estimating means 6, and the response frequency f of the speed control system including the motor 1 and the load 9 is always included.
The speed proportional gain, the speed integral gain, and the speed derivative gain are set so as to keep c constant.

More specifically, as shown in FIG. 2, an equivalent block diagram of the motor 1 and the load 9, a current I flowing through the motor 1, an actual speed V of the motor 1, a disturbance torque TL, and a moment of inertia JL of the load 9. , The moment of inertia JM of the electric motor 1, there is a relationship of equation (2).

[0033]

(Equation 2)

In the equation (2), the moment of inertia J generated at the shaft end of the electric motor 1 is given by the equation (3)

[0035]

[Equation 3]

## EQU1 ## By ignoring the disturbance torque TL, the inertia moment J is estimated from the current flowing through the motor 1 obtained by the current detection unit 5 by the inertia moment estimation unit 6 and the actual speed of the motor 1 obtained by the speed detection unit 4. It can be performed. Next, speed control means 2
Is that even if the moment of inertia J changes by dj, the speed proportional gain KSP and the speed integral gain K
SI and speed differential gain KSD are (J + dj) /
The response frequency fc of the speed control system can be kept constant by making the value J times.

(Embodiment 2) Next, Embodiment 2 of the present invention will be described with reference to FIG. The motor control device provided with the inertia moment estimating means 6 described above includes:
Switching gain means 10 is added to enable or disable speed gain switching.

First, the inertia moment estimating means 6 estimates the inertia moment J by ignoring the disturbance torque TL. For this reason, when the disturbance torque TL occurs, an accurate moment of inertia J cannot be estimated. Further, the disturbance torque TL is generated when the electric motor 1 is rotating.

On the other hand, when the motor 1 is rotating in a certain direction, the inertia moment of the load is generated at the shaft end of the motor 1 because the gears mesh with each other, and the motor 1 is almost stopped. It is not known which moment of inertia, no load or load, is occurring at the shaft end of the electric motor 1 when the motor 1 is in operation.

For this reason, when the speed command is smaller than the reference value, the inertia moment estimating means 6
, The respective speed gains (KSP + KSI + KSD) are changed to speed gains (KSP + KSI + KSD) suitable for the moment of inertia. Set the gain (KSP + KSI + KSD). Thus, the response frequency fc of the speed control system can be kept constant.

Embodiment 3 Next, Embodiment 3 of the present invention will be described with reference to FIG. In the third embodiment,
The integrator 71 integrates the position deviation between the actual position detected by the encoder (position detecting means) 8 and the position command, and the gain K
P is multiplied by the amplifier 72 and a speed command is calculated by the position control means 7. The speed command calculated by the position control means 7 is input to the motor control device having the inertia moment estimating means 6 described above.

At this time, the switching determination means 10 switches the speed gain according to the position command. Specifically, when the position command is equal to or less than the reference value, it is possible to know that the motor 1 is about to be stopped, and the moment of inertia JL is estimated by the moment of inertia The gain is changed to a speed gain suitable for the moment of inertia. Next, when the position command is equal to or greater than the reference value, it is possible to know that the vehicle is about to rotate, and the speed gain is set to a preset value suitable for the load inertia moment J. Thus, the response frequency fc of the speed control system can be kept constant.

(Embodiment 4) Next, Embodiment 4 of the present invention will be described with reference to FIG. In the fourth embodiment,
The integrator 71 integrates the position deviation between the actual position detected by the encoder (position detecting means) 8 and the position command, and the gain K
P is multiplied by the amplifier 72 and a speed command is calculated by the position control means 7. The speed command calculated by the position control means 7 is input to the motor control device having the inertia moment estimating means 6 described above.

At this time, the switching determination means 10 switches the speed gain based on the integral value of the position deviation. Specifically, when the integrated value of the position deviation is equal to or smaller than the reference value, it is possible to know that the position control of the electric motor 1 is being performed with good followability. Is estimated, and each speed gain is a speed gain (KSP + KSI + KS) suitable for the moment of inertia.
Change to D). Next, when the integrated value of the position deviation value is equal to or larger than the reference value, it is possible to know that the follow-up of the position control of the electric motor 1 is delayed, and it is suitable for the load inertia moment J set in advance. Speed gain. Thus, the response frequency fc of the speed control system can be kept constant.

(Fifth Embodiment) Next, a fifth embodiment of the present invention will be described with reference to FIG. In the fifth embodiment,
The integrator 71 integrates the position deviation between the actual position detected by the encoder (position detecting means) 8 and the position command, and the gain K
P is multiplied by the amplifier 72 and a speed command is calculated by the position control means 7. The speed command calculated by the position control means 7 is input to the motor control device having the inertia moment estimating means 6 described above.

At this time, the switching determination means 10 determines the speed gain (KSP + K
(SI + KSD). Specifically, when the integrated value of the position deviation is equal to or less than the reference value, it can be known that the machine tool is almost stopped, and the inertia moment JL is estimated by the inertia moment The gain (KSP + KSI + KSD) is changed to a speed gain suitable for the moment of inertia. Next, when the integrated value of the position deviation is equal to or larger than the reference value, it is possible to know that the machine tool is in operation, and the speed gain (KSP + KSI + KS) suitable for the load inertia moment J set in advance.
Set to D). Thus, the response frequency fc of the speed control system can be kept constant.

Embodiment 6 Next, Embodiment 6 of the present invention will be described with reference to FIG. In the sixth embodiment,
The control of the motor 1 to which the load 9 is added is performed by integrating the position deviation between the actual position detected by the encoder (position detecting means) 8 and the position command by the integrator 71 and multiplying the gain KP by the amplifier 72 and the speed command by the amplifier 72. Is calculated by the position control means 7.

The actual speed of the electric motor 1 is detected by the speed detecting means 4 and a current command is calculated by the speed control means 2 based on a speed deviation from the speed command. At this time, the speed control means 2
Then, the speed deviation is converted into a speed control proportional term 21 having a speed proportional gain KSP, a speed control integral term 22 having a speed integral gain KSI, and a speed control differential term 2 having a speed differential gain KSD.
The current command is calculated by adding 3. Further, based on the current command and the motor current detected by the current detection means 5, the torque of the motor is controlled by the current controller 3.

However, the fluctuation of the inertia moment J due to the play of the gears is such that when the motor 1 is rotating in a fixed direction, the inertia moment of the load is generated at the shaft end of the motor 1 because the gears mesh with each other. However, when the motor 1 is stopped, it is not known which moment of inertia, no load or load, is generated at the shaft end of the motor 1. Also,
When stopped, high speed control response is not required.

Further, the switching determining means 10 sets the speed gain (KSP + KSI + KSD) suitable for the load inertia moment when the motor 1 is going to rotate, and the speed at no load when the motor 1 is going to stop. Switching for setting the gain (KSP + KSI + KSD) is performed. Specifically, when the position command is equal to or less than the reference value, the speed gain (KSP + KSI + KSD) is adjusted to the speed gain (KSP
+ KSI + KSD), and when the position command is equal to or greater than the reference value, set a speed gain (KSP + KSI + KSD) suitable for the moment of inertia under load.

At this time, the speed gain (KSP + KSI +
KSD) is set so that the speed control response frequency fc of the electric motor 1 under load and no load does not change. With such a switching setting, the response frequency fc of the speed control system
Can be kept constant.

Embodiment 7 Next, Embodiment 7 of the present invention will be described with reference to FIG. In the seventh embodiment,
The control of the motor 1 to which the load 9 is added is performed by integrating the position deviation between the actual position detected by the encoder (position detecting means) 8 and the position command by the integrator 71 and multiplying the gain KP by the amplifier 72 and the speed command by the amplifier 72. Is calculated by the position control means 7. Further, the actual speed of the electric motor 1 is detected by the speed detecting means 4,
The current command is calculated by the speed control means 2 based on the speed deviation from the speed command. At this time, the speed control means 2 calculates a current command by adding the speed deviation to a proportional term 21 having a speed proportional gain KSP, an integral term 22 having a speed integral gain KSI, and a differential term 23 having a speed differential gain KSD. ing. Further, based on the current command and the motor current detected by the current detecting means 5, the torque of the motor is controlled by the current control means 3.

For this reason, the switching determination means 10 determines whether the motor 1
Is set to a speed gain (KSP + KSI + KSD) suitable for the moment of inertia when the delay is large relative to the position command, and to follow the position command, a speed gain (KSP + KSI + KSD) at no load is set. Is switched. Specifically, when the integrated value of the position deviation is equal to or less than the reference value, the speed gain (KSP + KSI + KS)
D) is changed to a speed gain (KSP + KSI + KSD) suitable for the moment of inertia without a load, and when the integrated value of the position deviation is equal to or more than the reference value, the speed gain (KSP + KSI + KSD) suitable for the moment of inertia with the load is applied. KSP + KSI + K
SD).

At this time, the speed gain (KSP + KSI +
KSD) is set so that the response frequency fc of the speed control system of the electric motor 1 at the time of no load under load does not change.
With such a switching setting, the response frequency f of the speed control system
c can be kept constant.

Embodiment 8 Next, Embodiment 8 of the present invention will be described with reference to FIG. In the eighth embodiment,
The control of the motor 1 to which the load 9 is added is performed by integrating the position deviation between the actual position detected by the encoder (position detecting means) 8 and the position command by the integrator 71 and multiplying the gain KP by the amplifier 72 and the speed command by the amplifier 72. Is calculated by the position control means 7. Further, the actual speed of the electric motor 1 is detected by the speed detecting means 4,
The current command is calculated by the speed control means 2 based on the speed deviation from the speed command. At this time, the speed control means 2 adds the speed deviation to the speed control proportional term 21 having the speed proportional gain KSP, the speed control integral term 22 having the speed integral gain KSI, and the speed control differential term 23 having the speed differential gain KSD. Is used to calculate the current command. Further, from the current command and the motor current detected by the current detecting means 5,
The torque of the electric motor is controlled by the current controller 3.

Even if the position command is 0, the integrated value of the deviation is not 0 due to the delay of the control system, and the motor 1 may rotate.
However, the position command is not 0 and the electric motor 1 may rotate. For this reason, it is determined that the electric motor 1 is in the stopped state reliably because both the position command and the integrated value of the position deviation are 0.
It is time.

For this reason, the switching determination means 10 sets the speed gain (KSP + KSI + KSD) suitable for the load moment of inertia when the machine tool is operating, and sets no speed when the machine tool is stopped. Speed gain (K
(SP + KSI + KSD). Specifically, when both the integral value of the position deviation and the position command are equal to or less than the reference, the speed gain (KSP + KSI + KS)
D) is changed to the speed gain (KSP + KSI + KSD) suitable for the moment of inertia without load, and when both the integrated value of the position deviation and the position command are equal to or more than the reference value, it is suitable for the moment of inertia with load. Speed gain (KS
P + KSI + KSD).

At this time, the speed gain (KSP + KSI +
KSD) is set so that the response frequency fc of the speed control system of the electric motor 1 at the time of no load under load does not change.
With such a switching setting, the response frequency f of the speed control system
c can be kept constant.

[0059]

As described above, the motor control device according to the present invention according to the first aspect of the present invention can reduce the inertia moment of the load applied to the motor without increasing the acceleration / deceleration time even in a machine having a play in the gear. The response frequency of the speed control system can always be controlled to be constant even with fluctuations, and the drive can be stably performed.

Further, the motor control device according to the second aspect of the present invention controls the response frequency of the speed control system to be always constant even in a machine having play in a gear, even when the inertia moment of a load applied to the motor fluctuates. It can be driven stably even if disturbance occurs.

Further, the motor control device according to the third aspect of the present invention can control the speed of a machine having play in gears without changing the acceleration / deceleration time without changing the acceleration / deceleration time. Can always be controlled to be constant, can be driven stably even when disturbance occurs, and can realize high-precision position control.

Further, the motor control device of the present invention according to the fourth aspect of the present invention provides speed control even for a machine with a play in gears, without increasing the acceleration / deceleration time, and also for fluctuations in the inertia moment of the load applied to the motor. Can always be controlled to be constant, can be driven stably even when disturbance occurs, and can realize high-precision position control.

The motor control device of the present invention according to the fifth aspect of the present invention provides speed control even for a machine with play in gears, without prolonging the acceleration / deceleration time, and also for fluctuations in the inertia moment of the load applied to the motor. Can always be controlled to be constant, stable driving can be performed even if disturbance occurs, and accurate position control can be realized.

The motor control device according to the present invention according to claim 6 has a simple configuration, and is applicable to a machine having play in gears.
It can constantly control the response frequency of the speed control system even when the inertia moment of the load added to the motor fluctuates, can drive stably even if disturbance occurs, and can realize highly accurate position control. .

Further, the motor control device of the present invention according to claim 7 has a simple structure, and is applicable to a machine having a play in gears.
Without lengthening the acceleration / deceleration time, the response frequency of speed control can be constantly controlled even when the inertia moment of the load added to the motor fluctuates. Position control can be realized.

The motor control device according to the present invention according to claim 8 has a simple structure, and does not increase the acceleration / deceleration time even in a machine with a play on the gears, without changing the inertia moment of the load applied to the motor. In addition, the response frequency of the speed control system can always be controlled to be constant, stable driving can be performed even when disturbance occurs, and highly accurate position control can be realized.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a motor control device according to a first embodiment of the present invention.

FIG. 2 is an equivalent block diagram of the electric motor according to the first embodiment.

FIG. 3 is a block diagram showing a motor control device according to the second embodiment;

FIG. 4 is a block diagram showing a motor control device according to the third embodiment;

FIG. 5 is a block diagram showing a motor control device according to the fourth embodiment.

FIG. 6 is a block diagram showing a motor control device according to the fifth embodiment.

FIG. 7 is a block diagram showing a motor control device according to the sixth embodiment.

FIG. 8 is a block diagram showing a motor control device according to the seventh embodiment.

FIG. 9 is a block diagram showing a motor control device according to the eighth embodiment.

FIG. 10 is a block diagram showing a configuration of a conventional digital AC servo device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Motor 2 Speed controller 3 Current controller 4 Speed detecting means 5 Current detecting means 6 Inertia moment estimating means 7 Position controller 8 Encoder (position detecting means) 9 Load 10 Switching determining means 21 Speed control proportional term 22 Speed control integral term 23 Speed control differential term 71 Integral term 72 Amplifier

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-8-19279 (JP, A) JP-A-7-131992 (JP, A) JP-A-6-225566 (JP, A) JP-A-4-1992 71381 (JP, A) JP-A-7-141030 (JP, A) JP-A-7-175527 (JP, A) JP-A-7-327382 (JP, A) (58) Fields investigated (Int. ⁷ , DB name) H02P 5/00 G05B 13/02

Claims (8)

(57) [Claims] An electric motor; a current control means for controlling a torque of the electric motor; a current detecting means for detecting a current flowing through the electric motor; a speed detecting means for detecting a speed of the electric motor; Means and an inertia moment estimating means for estimating an inertia moment of a load added to the electric motor from a current value and a speed value obtained from the speed detecting means, and an inertia estimated by the inertia moment estimating means when the speed becomes equal to or less than a reference speed. Speed calculated from moment
An electric motor control device comprising speed control means for controlling a speed by changing to a gain . 2. When the speed falls below a reference speed, the moment of inertia of the load applied to the motor is estimated, and the speed is changed to a speed gain calculated from the moment of inertia by speed control means. The motor control device according to claim 1 , further comprising a switching determination unit that enables control of the degree. 3. A position detecting means for detecting a position of the electric motor;
Position control means for controlling the position of the electric motor from the position detected by the position detection means and the position command; and estimating a moment of inertia of a load applied to the motor when the position command becomes equal to or less than a reference, and controlling the speed. the inertia mode by means
Control by changing to the speed gain calculated from the
2. The motor control device according to claim 1 , further comprising: a switching determination unit that enables the operation to be performed . 4. A position detecting means for detecting a position of the electric motor;
Position control means for controlling the position of the electric motor based on the position detected by the position detection means and the position command, and an electric motor is added when the integrated value of the deviation between the position of the electric motor and the position command becomes equal to or less than a reference. Estimate the moment of inertia of the load and calculate from the moment of inertia with the speed control means
Enable speed control by changing to speed gain
The motor control device according to claim 1 , further comprising a switching determination unit . 5. A position detecting means for detecting a position of a motor,
Position control means for controlling the position of the electric motor from the position and the position command detected by the position detection means, and when both the integrated value of the deviation between the position of the motor and the position command and the position command are below the reference, the motor Inertia model of the added load
The moment of inertia is estimated by the speed control means.
To control speed by changing to speed gain calculated from
2. The electric motor control device according to claim 1 , further comprising: a switching determination unit that validates the condition . 6. An electric motor, position detecting means for detecting a position of the electric motor, position control means for controlling a position of the electric motor from a position detected by the position detecting means and a position command, and a speed of the electric motor. Speed detection means for detecting
Said speed detecting means by controlling the speed of the motor from the speed command output from the position control means and the detected velocity, at the reference position command less inertia motor in a state without a load
An electric motor control device comprising a speed control means for changing to a speed gain suitable for the element . 7. An electric motor, position detecting means for detecting a position of the electric motor, position control means for controlling a position of the electric motor from a position detected by the position detecting means and a position command, and a speed of the electric motor. Speed detection means for detecting
Control the speed of the motor from the speed command output from the speed and position control means detected by the speed detecting means, when the integral value of the deviation between the position command and the position of the electric motor becomes the reference below, in the state without a load Speed suitable for moment of inertia
An electric motor control device having a speed control means for changing to a gain . 8. An electric motor, position detecting means for detecting the position of the electric motor, position control means for controlling the position of the electric motor from the position detected by the position detecting means and a position command, and a speed of the electric motor. Speed detection means for detecting
The speed of the motor is controlled based on the speed detected by the speed detecting means and the speed command output from the position control means, and when both the integrated value of the deviation between the position of the motor and the position command and the position command become equal to or less than a reference, the load is reduced. Inertia in the absence of
And a speed control means for changing the speed gain to a speed gain suitable for the motor.