JP2023004212A - Torque control device of motor and speed control device of motor - Google Patents

Abstract

To provide a torque control device of a motor capable of controlling torque and speed only by setting a limit position range and a limit speed range without providing a specific position limit device.SOLUTION: A torque control device of a motor includes a speed deviation calculator 11, a speed command value calculator 12, a position deviation calculator 2, a position command calculator 3, a position limiter 4, and a position control unit 5 for controlling a motor position from a motor position command value. The position limiter 4 sets the maximum value as the motor position command value when the position command value is larger than the maximum value in a limit position range, sets the minimum value as the motor position command value when the value is smaller than the minimum value, and sets the position command value calculated from the speed command value as the motor position command value when the value is within the limit position range.SELECTED DRAWING: Figure 4

Description

The present invention relates to a motor torque control device and a motor speed control device.

In the machine tool table drive, linear motion is achieved by connecting a ball screw to the motor. In such a mechanical device that performs linear motion, if the table tries to move beyond the movement limit point due to an operation error, the device may be damaged. In order to prevent such damage to the device, for example, a limit switch is provided at a position before the movement limit point.

For example, Patent Literature 1 discloses an AC servo control device used for table feed of a transfer machine or a numerically controlled (NC) machine tool. This AC servo control device uses the output of a speed amplifier as a torque command, and outputs positive and negative torque to the motor according to the polarity of the torque command to control the speed. The AC servo controller has detectors (limit switches) provided at both ends for maximum operation. The detector outputs an overtravel signal to the logic circuit when it detects that the table has reached the limit of travel. The logic circuit, when an overtravel signal is input, if the direction of the torque command at that time causes the table to move toward the movement limit point on the side of the detector outputting the overtravel signal, the built-in The dynamic braking circuit is activated to brake the motor and turn off the power elements of the main circuit.

JP-A-64-8883

However, the method of stopping the motor using such a limit switch requires a limit switch and wiring from the limit switch to the motor control device. Also, it is necessary to consider the distance that the table moves after the limit switch is activated until it stops. It gets complicated. Therefore, there is room for further improvement in the control of motors for table driving of machine tools.

Therefore, the present invention provides a torque control device for a motor that can control the torque and speed of a motor only by setting a limited position range or a limited speed range to be limited, without providing a specific position limiting device. and a motor speed controller.

A motor torque control device according to one aspect of the present invention includes:
A torque control device for a motor that controls the torque of the motor within a limit position range that is within the range of a preset first minimum value and first maximum value based on a torque command value input from the outside,
a position detector that detects the position of the motor;
a speed calculator that differentiates the position to calculate a motor speed;
a speed deviation calculator for calculating a speed deviation value indicating how much the motor is to be accelerated or decelerated from the current speed based on the torque command value;
a speed command value calculator that calculates a speed command value based on the speed deviation value and the motor speed;
a position deviation calculator for calculating a position deviation value indicating how much the motor should be moved from the current position based on the speed command value;
a position command calculator that calculates a position command value by adding the position to the position deviation value;
a position limiter that calculates a motor position command value so as to limit the position of the motor according to the position command value and the limit position;
a position control unit that controls the position of the motor based on the motor position command value;
The position limiter is
setting the first maximum value as the motor position command value when the position command value is greater than the first maximum value;
setting the first minimum value as the motor position command value when the position command value is smaller than the first minimum value;
When the position command value is within the restricted position range, the position command value calculated based on the speed command value is set as it is as the motor position command value.

A motor speed control device according to one aspect of the present invention includes:
A speed control device for a motor that controls the speed of the motor within a limit position range that is within a preset range of a first minimum value and a first maximum value based on a speed command value input from the outside,
a position detector that detects the position of the motor;
a position deviation calculator for calculating a position deviation value indicating how much the motor should be moved from the current position based on the speed command value;
a position command calculator that calculates a position command value by adding the position to the position deviation value;
a position limiter that calculates a motor position command value so as to limit the position of the motor according to the limit position;
a position control unit that controls the position of the motor based on the motor position command value;
The position limiter is
setting the first maximum value as the motor position command value when the position command value is greater than the first maximum value;
setting the first minimum value as the motor position command value when the position command value is smaller than the first minimum value;
When the position command value is within the restricted position range, the position command value calculated based on the speed command value is set as it is as the motor position command value.

According to the present invention, a torque control device for a motor is capable of controlling the torque and speed of a motor simply by setting a limited position range or a limited speed range to be limited, without providing a specific position limiting device. and a motor speed control device can be provided.

1 is a block diagram showing the configuration of a motor speed control device according to a first embodiment of the present invention; FIG. 2 is a block diagram of a position control unit in FIG. 1; FIG. 4(a) to 4(d) are graphs showing simulation results of motor position and motor speed controlled by a motor speed controller; FIG. 3 is a block diagram showing the configuration of a motor torque control device according to a second embodiment of the present invention; 5 is a block diagram of a speed command value calculator in FIG. 4; FIG. (a) to (g) are graphs showing simulation results of motor position, motor speed, and motor torque command value controlled by a motor torque control device.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. For the sake of convenience, descriptions of members having the same reference numbers as members already described in the description of the embodiment will be omitted. Also, the dimensions of each member shown in this drawing may differ from the actual dimensions of each member for convenience of explanation.

(First embodiment)
FIG. 1 is a block diagram showing the configuration of a motor speed control device according to a first embodiment of the present invention. A motor speed control device according to the first embodiment is a device in which a motor is mounted. A controller capable of controlling the speed of a motor within a limited position range.

As shown in FIG. 1, a speed control device for a motor M (hereinafter also referred to as a motor speed control device 1) includes a position deviation calculator 2, a position command calculator 3, a position limiter 4, and a position control unit. 5 , a position detector 6 and a motor speed calculator 7 .

A speed command value Vc for controlling the motor speed V of the motor M and a limit position PL for limiting the motor position P of the motor M are externally input to the motor speed control device 1 having such a configuration. be done. By externally inputting the speed command value Vc and the limit position PL, the motor speed control device 1 controls the speed of the motor M under a desired speed and a constant position limit.

A desired velocity command value Vc given from the outside is input to the position deviation calculator 2 . The position deviation calculator 2 calculates a position deviation value Pd1 indicating how far the motor M should be moved from the current position based on the input speed command value Vc.

The calculated positional deviation value Pd1 is input to the positional command calculator 3 . A motor position P of the motor M detected by the position detector 6 is input to the position command calculator 3 . The position detector 6 is composed of an encoder capable of detecting the position of the motor M, for example. The position command calculator 3 adds the position deviation value Pd1 and the motor position P to calculate a position command value Pc based on the speed command value Vc.

The calculated position command value Pc is input to the position limiter 4 . A desired limit position PL for limiting the motor position P is input to the position limiter 4 . The position limiter 4 calculates a motor position command value Pmc based on the position command value Pc and the limit position PL so as to limit the motor position P according to the position command value Pc and the limit position PL.

The calculated motor position command value Pmc is input to the position controller 5 . The position control unit 5 position-controls the motor position P of the motor M based on the motor position command value Pmc.

FIG. 2 is a block diagram of the position control section 5. As shown in FIG. As shown in FIG. 2 , the position controller 5 has a position controller 51 , a speed controller 52 and a torque controller 53 .

A motor position command value Pmc calculated by the position limiter 4 is input to the position controller 51 of the position controller 5 . A motor position P of the motor M detected by the position detector 6 is input to the position controller 51 . The position controller 51 subtracts the current motor position P from the motor position command value Pmc to calculate a position deviation value Pd2 indicating how much the current position of the motor M should be moved. The position controller 51 calculates a motor speed command value Vmc based on the calculated position deviation value Pd2.

The calculated motor speed command value Vmc is input to the speed controller 52 . A motor speed V of the motor M calculated by the motor speed calculator 7 is input to the speed controller 52 . A motor speed calculator 7 calculates a motor speed V by differentiating the motor position P detected by the position detector 6 . The speed controller 52 subtracts the current motor speed V from the motor speed command value Vmc to calculate a speed deviation value Vd0 that indicates how much the current speed of the motor M should be accelerated or decelerated. Speed controller 52 calculates motor torque command value Tmc based on calculated speed deviation value Vd0.

Motor torque command value Tmc is input to torque controller 53 . The torque controller 53 controls the motor M so that a desired motor torque T (according to the command value) is output based on the motor torque command value Tmc.

Then, the position detector 6 detects the motor position P moved by the motor torque T output from the motor M, and position control is performed so that the motor position command value Pmc and the current motor position P of the motor M match. Thus, the control loop by the motor speed control device 1 is executed.

Next, calculation of the position control loop in the position controller 51 will be described. In the motor speed control device 1, for example, if the position controller 51 is composed of a proportional controller and its gain is G, the calculation of the position control loop in the position controller 51 is as follows.

Motor position command value Pmc−Motor position P=Position deviation value Pd2 (1)
Position deviation value Pd2×Proportional controller gain G=Motor speed command value Vmc (2)

From the equations (1) and (2), the motor position command value Pmc can be calculated back from the motor speed command value Vmc as follows.
Position deviation value Pd2=Motor speed command value Vmc/Proportional controller gain G (3)
Motor position command value Pmc=position deviation value Pd2+motor position P (4)

In the present invention, the position command value Pc is calculated based on the speed command value Vc given from the outside using the relationships of the above equations (3) and (4).
Position deviation value Pd1 based on speed command value Vc=speed command value Vc/G (5)
Position command value Pc based on speed command value Vc=position deviation value Pd1 based on speed command value Vc+motor position P (6)

Then, the motor position command value Pmc is obtained by limiting the position based on the limit position PL set from the outside in the position limiter 4 with respect to the position command value Pc based on the found speed command value Vc.
If the motor position P of the motor M is controlled based on this motor position command value Pmc,
Motor speed command value Vmc
= position deviation value Pd2 × gain G of proportional controller
= (motor position command value Pmc - motor position P) x gain G of proportional controller

Here, when the position command value Pc is within the limit position range, that is, when the position command value Pc calculated based on the speed command value Vc is not restricted by the limit position PL, the motor position command value Pmc= The position command value Pc is based on the speed command value Vc. In this case, the position command value Pc calculated based on the speed command value Vc is directly set as the motor position command value Pmc.

For this reason,
Motor speed command value Vmc
= (position command value Pc based on speed command value Vc - motor position P) x gain G of proportional controller
= {(position deviation value Pd1 based on speed command value Vc + motor position P) - motor position P} x gain G of proportional controller
= (position deviation value Pd1 based on speed command value Vc) × gain G of proportional controller
= (speed command value Vc/G) × gain G of proportional controller
= Speed command value Vc
, the motor speed command value Vmc matches the speed command value Vc, and the speed of the motor M is controlled based on this motor speed command value Vmc to achieve a speed corresponding to the motor speed command value Vmc, that is, a speed corresponding to the speed command value Vc. The motor M is speed-controlled.

On the other hand, when the position command value Pc is not within the limit position range, that is, when the position command value Pc calculated based on the speed command value Vc is restricted by the limit position PL, the motor position command value Pmc becomes the position limit value (limit position PL). For example, when the position command value Pc is larger than the maximum value of the restricted position range, the maximum value is set as the motor position command value Pmc. If the position command value Pc is smaller than the minimum value of the restricted position range, the minimum value is set as the motor position command value Pmc. Then, position control of the motor M is performed based on the limit position PL (maximum value, minimum value), and the motor position P is controlled to the limit position PL.

As a result, if the limit position PL is set to the upper and lower limits of the movable range of the machine, the speed is controlled within the movable range, and when the movable limit is reached, the position is controlled to the movable limit position.

Further, the limit position PL can also determine the limit value of the motor position P based on a predetermined threshold value, a predetermined table value, a predetermined function value, or the like. In this case, it goes without saying that the term "predetermined" includes being able to be arbitrarily determined. It also includes that it is possible to set

FIG. 3 is a graph showing simulation results of the motor position P and the motor speed V controlled by the motor speed controller 1. FIG. FIG. 3(a) is a graph showing changes in the speed command value Vc. FIG. 3(b) is a graph showing changes in the position command value Pc based on the speed command value Vc. 3(c) is a graph showing changes in the motor position command value Pmc and the motor position P. FIG. FIG. 3(d) is a graph showing changes in the motor speed command value Vmc and the motor speed V. FIG.

Trapezoidal operation with speeds up to 2500 min ⁻¹ was performed in this simulation. The limit position range has a minimum value of 0 rad and a maximum value of 19 rad.

As shown in FIGS. 3A to 3D, when the speed command value Vc increases, the position command value Pc based on the speed command value Vc, the motor position command value Pmc, the motor position P, the motor Speed command value Vmc and motor speed V also increase. When the speed command value Vc increases and the position command value Pc based on the speed command value Vc reaches the maximum value of 19 rad in the restricted position range, the motor position command value Pmc is limited to the maximum value of 19 rad (see FIG. 3(c). ). When the motor position command value Pmc reaches the maximum value of 19 rad, the motor speed command value Vmc decreases, and the motor M stops at the position limited by the maximum value of 19 rad of the limit position range (see FIG. 3(d)).

Similarly, in the operation in the opposite direction, when the speed command value Vc rises in the negative direction and the position command value Pc based on the speed command value Vc reaches the minimum value of 0 rad of the restricted position range, the motor position command value Pmc reaches the minimum value of 0 rad. (see FIG. 3(c)). When the motor position command value Pmc reaches the minimum value 0 rad, the motor speed command value Vmc increases, and the motor M stops at the position limited by the minimum value 0 rad of the limit position range (see FIG. 3(d)).

As described above, in the motor speed control device 1 of the first embodiment, the position control system performs reverse calculation of the motor speed command value Vmc from the motor position command value Pmc, based on the speed command value Vc. , a position command value Pc is calculated based on the speed command value Vc, a motor position command value Pmc is obtained by performing position limitation, and a motor speed command value Vmc is calculated based on the motor position command value Pmc.

Therefore, when the position command value Pc is not restricted by the limit position PL, the motor position command value Pmc=the position command value Pc based on the speed command value Vc, and the motor speed command value Vmc is equal to the speed command value Vc. is output, and the speed of the motor M is controlled to the motor speed V that matches the speed command value Vc. On the other hand, when the position command value Pc is limited by the limit position PL, the motor position command value Pmc becomes the position limit value, and the motor position P of the motor M is controlled to the position limit value. Therefore, if position limit values are set at the upper and lower limits of the movable range of the controlled machine, speed control is performed within the limited position range, and when the limit of the limited position range is reached, the position is controlled to the movable limit position.

As described above, the motor speed control device 1 according to the present embodiment calculates the position command value Pc based on the speed command value Vc, performs position limitation to obtain the motor position command value Pmc, and calculates the motor position command value Pmc. It is possible to realize speed control having a motor position P limiting function with a simple configuration in which the position of the motor M is controlled based on Pmc. When the set limit position range is not exceeded, the speed of the motor M can be controlled at the speed V that matches the set speed command value Vc. M can be stopped. As a result, the speed of the motor can be controlled simply by setting a limit position range to be limited, without providing a specific position limit device such as a limit switch.

(Second embodiment)
FIG. 4 is a block diagram showing the configuration of a motor torque control device according to a second embodiment of the present invention. FIG. 5 is a block diagram of the speed command value calculator 12 in FIG. A torque control device for a motor according to the second embodiment is a device in which a motor is mounted, in which the speed range of the device (hereinafter also referred to as "speed limit range") and the movable range of the device (hereinafter referred to as "limit position ) and are externally set in advance, the control device is capable of controlling the torque of the motor within the set speed limit range and the limit position range.

As shown in FIG. 4, the torque control device for the motor M (hereinafter also referred to as the motor torque control device 10) includes a speed deviation calculator 11, a speed command value calculator 12, a position deviation calculator 2, a position A command calculator 3 , a position limiter 4 , a position controller 5 , a position detector 6 , and a motor speed calculator 7 are provided. The speed command value calculator 12 has a first speed command value calculator 121 and a speed limiter 122, as shown in FIG. The position control section 5 has the same configuration as the position control section 5 of the motor speed control device 1 of the first embodiment shown in FIG.

The motor torque control device 10 having such a configuration includes a torque command value Tc for controlling the motor torque T of the motor M, a limit speed VL for limiting the motor speed V of the motor M, and a motor A limit position PL for limiting the position P is input from the outside. Thereby, the motor torque control device 10 performs torque control of the motor M under a desired torque and constant speed limit and position limit.

A desired torque command value Tc given from the outside is input to the speed deviation calculator 11 . The speed deviation calculator 11 calculates a speed deviation value Vd1 indicating how much the motor M should be accelerated or decelerated from the current speed based on the input torque command value Tc.

The calculated speed deviation value Vd1 is input to the speed command value calculator 12 . The motor speed V of the motor M calculated by the motor speed calculator 7 is input to the speed command value calculator 12 . A speed limit VL for limiting the motor speed V is input to the speed command value calculator 12 . The speed command value calculator 12 is a calculator capable of controlling the speed of the motor M within a preset speed limit range.

As shown in FIG. 5 , the speed deviation value Vd1 calculated by the speed deviation calculator 11 is input to the first speed command value calculator 121 of the speed command value calculator 12 . The motor speed V of the motor M calculated by the motor speed calculator 7 is also input to the first speed command value calculator 121 . A desired speed limit VL for limiting the motor speed V is input to the speed limiter 122 of the speed command value calculator 12 .

The first speed command value calculator 121 adds the motor speed V to the speed deviation value Vd1 to calculate a first speed command value Vc0 based on the torque command value Tc.

The calculated first speed command value Vc0 is input to speed limiter 122 . Based on the first speed command value Vc0 and the speed limit VL, the speed limiter 122 sets the speed command value Vc so as to limit the motor speed V of the motor M according to the first speed command value Vc0 and the speed limit VL. calculate.

The calculated speed command value Vc is input to the position deviation calculator 2 .
Returning to FIG. 4, the position deviation calculator 2 calculates a position deviation value Pd1 indicating how much the motor M should be moved from the current position based on the input speed command value Vc. The configuration after calculator 2 (position command calculator 3, position limiter 4, and position control unit 5) is the same as the configuration of the first embodiment shown in FIGS. Therefore, descriptions thereof are omitted.

Next, computation of the speed control loop in the speed controller 52 and the position control loop in the position controller 51 of the motor torque control device 10 will be described. In the motor torque control device 10, for example, the speed controller 52 and the position controller 51 are composed of proportional controllers, the gain of the speed controller 52 is GV, and the gain of the position controller 51 is GP. In this case, calculations of the speed control loop in the speed controller 52 and the position control loop in the position controller 51 are as follows.

First speed command value Vc0−motor speed V=speed deviation value Vd1 (1)
Speed deviation value Vd1×speed controller gain GV=torque command value Tc (2)
Motor position command value Pmc−Motor position P=Position deviation value Pd2 (3)
Position deviation value Pd2×position controller gain GP=motor speed command value Vmc (4)

From the equations (1) to (4), the first speed command value Vc0 can be calculated from the torque command value Tc, and the motor position command value Pmc can be calculated from the motor speed command value Vmc.
Speed deviation value Vd1=Torque command value Tc/Gain GV of speed controller (5)
First speed command value Vc0=speed deviation value Vd1+motor speed V (6)
Position deviation value Pd2=motor speed command value Vmc/position controller gain GP (7)
Motor position command value Pmc=position deviation value Pd2+motor position P (8)

In the present invention, the first speed command value Vc0 is calculated based on the torque command value Tc given from the outside using the relationships of the above equations (5) to (8).
Speed deviation value Vd1 based on torque command value Tc=torque command value Tc/gain GV of speed controller
First speed command value Vc0 based on torque command value Tc=Speed deviation value Vd1 based on torque command value Tc+Motor speed V

Then, with respect to the first speed command value Vc0 based on the obtained torque command value Tc, the speed is limited based on the speed limit VL set from the outside in the speed limiter 122, and the speed command value Vc after the limit is obtained. demand.

Similarly, a position command value Pc based on the restricted speed command value Vc is calculated from the restricted speed command value Vc.
Position deviation value Pd1 based on speed command value Vc after limitation=speed command value Vc after limitation/gain GP of position controller
Position command value Pc based on speed command value Vc after limitation=Position deviation value Pd1 based on speed command value Vc after limitation+Motor position P

Then, the motor position command value Pmc is obtained by limiting the position based on the limit position PL set from the outside in the position limiter 4 with respect to the position command value Pc based on the determined speed command value Vc after the limit. .

If the motor position P of the motor M is controlled based on this motor position command value Pmc,
Motor speed command value Vmc
= positional deviation value Pd2 x position controller gain GP
= (motor position command value Pmc - motor position P) x position controller gain GP
Torque command value Tc
= speed deviation value Vd1 × gain GV of speed controller
= (first speed command value Vc0 - motor speed V) x speed controller gain GV

Here, when the position command value Pc is within the limit position range, that is, when the position command value Pc calculated based on the torque command value Tc is not restricted by the limit position PL, the motor position command value Pmc= The position command value Pc is based on the restricted speed command value Vc. In this case, the position command value Pc calculated based on the speed command value Vc is directly set as the motor position command value Pmc.

For this reason,
Motor speed command value Vmc
= (motor position command value Pmc - motor position P) x position controller gain GP
= (position command value Pc based on speed command value Vc after limit-motor position P) x position controller gain GP
= {(position deviation value Pd1 based on speed command value Vc after limit + motor position P) - motor position P} x position controller gain GP
= (Position deviation value Pd1 based on speed command value Vc after limit) x gain GP of position controller
= (speed command value Vc after limit/gain GP of position controller) x gain GP of position controller
= speed command value Vc after restriction
As a result, the motor speed command value Vmc matches the speed command value Vc after the limit.

Furthermore, when the first speed command value Vc0 is within the speed limit range, that is, when the first speed command value Vc0 calculated based on the torque command value Tc is not subject to the speed limit by the speed limit VL, Speed command value Vc=first speed command value Vc0. In this case, the first speed command value Vc0 calculated based on the torque command value Tc is directly set as the speed command value Vc.

For this reason,
Motor torque command value Tmc
= (motor speed command value Vmc - motor speed V) x speed controller gain GV
= (speed command value after limit Vc - motor speed V) x speed controller gain GV
= (first speed command value Vc0 - motor speed V) x speed controller gain GV
= {(speed deviation value Vd1 based on torque command value Tc + motor speed V) - motor speed V} x speed controller gain GV
= (speed deviation value Vd1 based on torque command value Tc) x gain GV of speed controller
= torque command value Tc/gain GV of speed controller x gain GV of speed controller
= torque command value Tc
, the motor torque command value Tmc matches the torque command value Tc, and the motor M is torque-controlled based on this motor torque command value Tmc, and the torque corresponding to the motor torque command value Tmc, that is, the torque corresponding to the torque command value Tc The motor M is torque-controlled.

On the other hand, when the first speed command value Vc0 is not within the speed limit range, that is, when the first speed command value Vc0 calculated based on the torque command value Tc is subject to the speed limit by the speed limit VL, The speed command value Vc becomes the speed limit value (speed limit VL) and the speed is limited. For example, when the first speed command value Vc0 is larger than the maximum value of the speed limit range, the maximum value is set as the speed command value Vc. If the first speed command value Vc0 is smaller than the minimum value of the speed limit range, the minimum value is set as the speed command value Vc. Then, speed control of the motor M is performed based on the speed limit VL (maximum value, minimum value), and the motor speed V is controlled to the speed limit VL.

Further, when the position command value Pc is not within the limit position range, that is, when the position command value Pc calculated based on the torque command value Tc is subject to the position limit by the limit position PL, the motor position command value Pmc does not reach the position It becomes a limit value (limit position PL). For example, when the position command value Pc is larger than the maximum value of the restricted position range, the maximum value is set as the motor position command value Pmc. If the position command value Pc is smaller than the minimum value of the restricted position range, the minimum value is set as the motor position command value Pmc. Then, position control of the motor M is performed based on the limit position PL (maximum value, minimum value), and the motor position P is controlled to the limit position PL.

As a result, if the limit position PL is set at the upper and lower limits of the movable range of the machine, the torque is controlled within the movable range, and when the movable limit is reached, the position is controlled to the movable limit position.

FIG. 6 is a graph showing simulation results of motor position P, motor speed V, and motor torque command value Tmc controlled by motor torque control device 10 . FIG. 6(a) is a graph showing changes in the torque command value Tc. FIG. 6(b) is a graph showing changes in the first speed command value Vc0 based on the torque command value Tc. FIG. 6(c) is a graph showing changes in the speed command value Vc after the limitation. FIG. 6(d) is a graph showing changes in the position command value Pc based on the restricted speed command value Vc. 6(e) is a graph showing changes in the motor position command value Pmc and the motor position P. FIG. 6(f) is a graph showing changes in the motor speed command value Vmc and the motor speed V. FIG. FIG. 6(g) is a graph showing changes in the motor torque command value Tmc.

In this simulation, commanded operation with a torque of ±20 Nm was performed. A limited speed range is set to ±2500 min ⁻¹ and a limited position range is set to a minimum value of 0 rad and a maximum value of 10 rad.

As shown in FIGS. 6A to 6C, when the torque command value Tc increases and the first speed command value Vc0 based on the torque command value Tc rises to the maximum value 2500 min ⁻¹ of the speed limit range, the limit The subsequent speed command value Vc is limited to a maximum value of 2500min ^-1 . Further, when the torque command value Tc increases and the position command value Pc based on the restricted speed command value Vc reaches the maximum value of 10 rad in the restricted position range, the motor position command value Pmc is limited to the maximum value of 10 rad (Fig. 6(d), (e)). When the motor position command value Pmc reaches the maximum value of 10 rad, the motor speed command value Vmc decreases, and the motor M stops at the position limited by the maximum value of 10 rad of the limit position range (see FIG. 6(f)). Also, the motor torque command value Tmc decreases as the motor speed command value Vmc decreases (see FIG. 6(g)).

Similarly, in the operation in the opposite direction, when the torque command value Tc rises in the negative direction and the first speed command value Vc0 based on the torque command value Tc rises to the minimum value of the speed limit range -2500 min ^-1 , after the limit The speed command value Vc is limited to a minimum value of -2500 min ^-1 (see FIGS. 6(a) to 6(c)). Further, when the torque command value Tc increases in the negative direction and the position command value Pc based on the speed command value Vc after restriction reaches the minimum value of 0 rad in the restricted position range, the motor position command value Pmc is limited to the minimum value of 0 rad. (see FIGS. 6(d) and (e)). When the motor position command value Pmc reaches the minimum value of 0 rad, the motor speed command value Vmc increases, and the motor M stops at the position restricted by the minimum value of 0 rad in the restricted position range (see FIG. 6(f)). Further, the motor torque command value Tmc increases as the motor speed command value Vmc increases (see FIG. 6(g)).

As described above, in the motor torque control device 10 of the second embodiment, the position control system calculates the motor speed command value Vmc from the motor position command value Pmc, and the speed control system calculates the motor torque command value from the motor speed command value Vmc. A first speed command value Vc0 based on the torque command value Tc is calculated based on the torque command value Tc by a method of performing reverse calculation of the calculation for calculating Tmc, and the speed command value Vc after the limit is obtained by limiting the speed. , based on the speed command value Vc after limitation, a position command value Pc based on the speed command value Vc after limitation is calculated, a motor position command value Pmc is obtained by performing position limitation, and based on the motor position command value Pmc , a motor speed command value Vmc is calculated, and a motor torque command value Tmc is calculated based on the motor speed command value Vmc.

Therefore, when the position command value Pc is not limited by the limit position PL or when the first speed command value Vc0 is not limited by the speed limit VL, the motor torque command value Tmc=torque command value Tc, a motor torque command value Tmc that matches the torque command value Tc is output, and the motor M is torque-controlled to a torque that matches the torque command value Tc.

On the other hand, when the first speed command value Vc0 is limited by the speed limit VL, the speed command value Vc is limited to the speed limit value (speed limit VL). When the position command value Pc is limited by the limit position PL, the motor position command value Pmc becomes the position limit value, and the motor position P of the motor M is controlled to the position limit value. Therefore, if position limit values are set at the upper and lower limits of the movable range of the controlled machine, torque control is performed within the limit position range, and when the limit of the limit position range is reached, the position is controlled to the limit position of movement.

As described above, the motor torque control device 10 according to the present embodiment calculates the first speed command value Vc0 based on the torque command value Tc, limits the speed, obtains the speed command value Vc after the limit, and With a simple configuration, the position command value Pc is calculated based on the speed command value Vc after restriction, the motor position command value Pmc is obtained by performing position restriction, and the position of the motor M is controlled based on the motor position command value Pmc. Torque control with limiting functions for motor position P and motor speed V can be realized. Then, when the set speed limit range and the limit position range are not exceeded, the motor M can be torque-controlled with the motor torque T exactly as the set torque command value Tc. When it reaches, the motor M can be stopped at the limit limit position after limiting the speed of the motor M to the limit limit speed. As a result, the torque of the motor can be controlled simply by setting the limit speed range and the limit position range to be limited, for example, without providing a specific position limit device such as a limit switch.

Although the embodiments of the present invention have been described above, it goes without saying that the technical scope of the present invention should not be limitedly interpreted by the description of the embodiments. It should be understood by those skilled in the art that this embodiment is merely an example, and that various modifications of the embodiment are possible within the scope of the invention described in the claims. The technical scope of the present invention should be determined based on the scope of the invention described in the claims and their equivalents.

1 motor speed controller 2 position deviation calculator 3 position command calculator 4 position limiter 5 position controller 6 position detector 7 motor speed calculator 10 motor torque controller 11 speed deviation calculator 12 speed command value calculator 51 position Controller 52 Speed controller 53 Torque controller 121 First speed command value calculator 122 Speed limiter M Motor P Motor position Pc Position command values Pd1, Pd2 Position deviation value PL Limit position Pmc Motor position command value Tc Torque command value Tmc Motor torque command value V Motor speed Vc Speed command value Vc0 First speed command values Vd0, Vd1 Speed deviation value Vmc Motor speed command value VL Speed limit

Claims (5)

A torque control device for a motor that controls the torque of the motor within a limit position range that is within the range of a preset first minimum value and first maximum value based on a torque command value input from the outside,
a position detector that detects the position of the motor;
a speed calculator that differentiates the position to calculate a motor speed;
a speed deviation calculator for calculating a speed deviation value indicating how much the motor is to be accelerated or decelerated from the current speed based on the torque command value;
a speed command value calculator that calculates a speed command value based on the speed deviation value and the motor speed;
a position deviation calculator for calculating a position deviation value indicating how much the motor should be moved from the current position based on the speed command value;
a position command calculator that calculates a position command value by adding the position to the position deviation value;
a position limiter that calculates a motor position command value so as to limit the position of the motor according to the position command value and the limit position;
a position control unit that controls the position of the motor based on the motor position command value;
The position limiter is
setting the first maximum value as the motor position command value when the position command value is greater than the first maximum value;
setting the first minimum value as the motor position command value when the position command value is smaller than the first minimum value;
A torque control device for a motor, wherein the position command value calculated based on the speed command value is directly set as the motor position command value when the position command value is within the restricted position range. The position control unit
a position controller that calculates a motor speed command value based on the difference between the position and the motor position command value;
a speed controller that calculates a motor torque command value based on the difference between the motor speed command value and the motor speed;
2. The motor torque control device according to claim 1, further comprising a motor torque controller for controlling said motor so as to generate a desired torque based on said motor torque command value. The speed command value calculator controls the speed of the motor within a speed limit range that is within a preset range of a first minimum value and a first maximum value,
The speed command value calculator,
a first speed command value calculator that calculates a first speed command value by adding the motor speed to the speed deviation value;
a speed limiter that calculates the speed command value so as to limit the speed of the motor according to the first speed command value and the speed limit;
The speed limiter is
setting the first maximum value as the speed command value when the first speed command value is greater than the first maximum value;
setting the first minimum value as the speed command value when the first speed command value is smaller than the first minimum value;
2. The motor according to claim 1, wherein when the first speed command value is within the speed limit range, the first speed command value calculated based on the torque command value is set as it is as the speed command value. Torque controller. A speed control device for a motor that controls the speed of the motor within a limit position range that is within a preset range of a first minimum value and a first maximum value based on a speed command value input from the outside,
a position detector that detects the position of the motor;
a position deviation calculator for calculating a position deviation value indicating how much the motor should be moved from the current position based on the speed command value;
a position command calculator that calculates a position command value by adding the position to the position deviation value;
a position limiter that calculates a motor position command value so as to limit the position of the motor according to the position command value and the limit position;
a position control unit that controls the position of the motor based on the motor position command value;
The position limiter is
setting the first maximum value as the motor position command value when the position command value is greater than the first maximum value;
setting the first minimum value as the motor position command value when the position command value is smaller than the first minimum value;
A speed control device for a motor, wherein the position command value calculated based on the speed command value is directly set as the motor position command value when the position command value is within the restricted position range. The position control unit
a position controller that calculates a motor speed command value based on the difference between the position and the motor position command value;
a motor speed calculator that differentiates the position to calculate the motor speed;
a speed controller that calculates a motor torque command value based on the difference between the motor speed command value and the motor speed;
5. The motor speed control device according to claim 4, further comprising a torque controller for controlling said motor so as to generate a desired torque based on said motor torque command value.

Images