JP2021058028A - Control device and control method - Google Patents

Abstract

To provide a control device and the like capable of promptly adjusting an angle of a mirror to a target angle, even when a control is performed by using a feedback control.SOLUTION: A control device has rotation speed calculation means for calculating an actual rotation speed corresponding to an actual rotation speed of a motor from a detected rotation angle which is a rotation angle of the motor detected, by using a correction value according to the rotation angle of the motor oscillating a mirror, deviation calculation means for calculating a deviation between a target rotation speed and the actual rotation speed calculated by the rotation speed calculation means, and setting means for setting target current supplied to the motor by using the deviation calculated by the deviation calculation means.SELECTED DRAWING: Figure 3

Description

The present invention relates to a motor control device and a control method.

Conventionally, a galvano scanner that can position a mirror at high speed regardless of the swing angle has been proposed.
For example, the galvano scanner described in Patent Document 1 is configured as follows. That is, in order to operate the actuator that swings the mirror based on the deviation between the command signal and the current position, the gain change of the actuator is measured according to the swing angle, and the actuator is operated so as to eliminate the gain change. Correct the amount. More specifically, the target trajectory generation processing unit calculates the swing angle target value of the galvano scanner based on the target positioning angle, and generates the target trajectory of the scanner servo mechanism. This target value is obtained by subtracting the swing angle of the scanner detected by the subtracting means to obtain a deviation. This deviation is subjected to control calculation processing by the compensation element to calculate the manipulated variable signal. The output signal of the compensation element is input to the D / A converter via the torque constant fluctuation compensation unit. Then, the torque constant fluctuation compensator refers to the memory according to the swing angle, that is, the swing angle, so as to cancel the change in the torque constant (for example, equal to the maximum value of the torque constant obtained by the measurement). ) Amplifies the operation amount signal and outputs it to the D / A converter.

Japanese Unexamined Patent Publication No. 2005-234215

In order to position the mirror at high speed in the entire swing range of the galvano scanner, it is desirable to consider that the responsiveness of the motor changes due to the change in torque constant. This also applies when the drive of the motor is controlled by using feedback control.
An object of the present invention is to provide a control device or the like capable of quickly adjusting the angle of a mirror to a target angle even when controlling using feedback control.

The present invention completed for the above object uses a correction value according to the rotation angle of the motor that swings the mirror, and uses the detected rotation angle, which is the rotation angle of the motor, to indicate the actual rotation speed of the motor. The rotation speed calculation means for calculating the actual rotation speed corresponding to the above, the deviation calculation means for calculating the deviation between the target rotation speed and the actual rotation speed calculated by the rotation speed calculation means, and the deviation calculation means have calculated. It is a control device including a setting means for setting a target current to be supplied to the motor by using the deviation.
Here, the rotation speed calculation means may calculate the actual rotation speed by using the differential value obtained by differentiating the detected rotation angle and the correction value.
Further, the rotation speed calculation means may calculate the actual rotation speed by using a value obtained by multiplying the detected rotation angle by a predetermined constant.
Further, an angle control means for setting the target rotation speed by performing angle feedback processing so that the deviation between the target rotation angle and the detected rotation angle becomes zero may be provided.
Further, the setting means may set the target current by using the second correction value according to the rotation angle of the motor.
From another point of view, the present invention performs angle control that performs angle feedback processing so that the deviation between the target rotation angle and the detected rotation angle, which is the rotation angle of the motor that swings the detected mirror, becomes zero. The output value from the differential compensation means is corrected by using the means, the differential compensation means for multiplying the value obtained by differentiating the detected rotation angle by a predetermined constant, and the correction value according to the rotation angle of the motor. It includes a correction means, a setting means for adding an output value from the angle control means and an output value from the correction means at a predetermined ratio, and setting a target current to be supplied to the motor. It is a control device.
Here, the setting means may also add a value obtained by multiplying the detected rotation angle by a predetermined constant at a predetermined ratio.
Further, the setting means incompletely integrates the detected current of the motor with a predetermined integration time constant, and also obtains a value obtained by differentiating with a predetermined differential time constant as a predetermined ratio. You may add with.
From another point of view, the present invention uses a correction value according to the rotation angle of the motor that swings the mirror, and uses the detected rotation angle of the motor to actually rotate the motor. This is a control method in which an actual rotation speed corresponding to a speed is calculated, a deviation between the target rotation speed and the actual rotation speed is calculated, and the target current to be supplied to the motor is set using the deviation.
From another point of view, the present invention performs angle feedback processing so that the deviation between the target rotation angle and the detected rotation angle, which is the rotation angle of the motor that swings the detected mirror, becomes zero. After multiplying the differentiated value of the detected rotation angle by a predetermined constant to perform differential compensation, the corrected value corresponding to the rotation angle of the motor is used to correct the value after the differential compensation, and after the angle feedback process. This is a control method in which the output value of the above and the output value after correction using the correction value are added at a predetermined ratio to set a target current to be supplied to the motor.

According to the present invention, it is possible to provide a control device or the like capable of quickly adjusting the angle of the mirror to the target angle even when the control is performed by using the feedback control.

It is a figure which shows an example of the schematic structure of the galvano scanner which concerns on this embodiment. It is a figure which shows an example of the schematic structure of the motor which concerns on this embodiment. It is an example of the block diagram which shows the structure of the control device which concerns on 1st Embodiment. It is the schematic of the control map which shows the example of the relationship between the detection rotation angle and a correction value. (A) is a measurement result when the mirror is positioned by using the control device according to the first embodiment. (B) is a measurement result when the mirror is positioned by using the control device according to the comparative example. It is an example of the block diagram which shows the structure of the control device which concerns on 2nd Embodiment. This is an example of a block diagram showing a configuration of a control device according to a third embodiment. This is an example of a block diagram showing a configuration of a control device according to a fourth embodiment.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings.
FIG. 1 is a diagram showing an example of a schematic configuration of a galvano scanner 1 according to the present embodiment.
FIG. 2 is a diagram showing an example of a schematic configuration of a motor according to the present embodiment.
The galvano scanner 1 includes a motor 10, a mirror 20, an angle detector 30 that detects the rotation angle of the motor 10, and a control device 100 that controls the drive of the motor 10 using the rotation angle detected by the angle detector 30. , Is equipped.

The motor 10 is a moving magnet type motor including a rotor 60, a stator 70, and a housing 80 for accommodating the stator 70. The motor 10 may be a moving coil type motor or other motor.
The rotor 60 has a rotating shaft 61 and a main magnet 62 mounted on the rotating shaft 61. Hereinafter, the axial direction of the rotating shaft 61 may be simply referred to as “axial direction”. Further, in the axial direction, the left side of FIG. 2 may be referred to as "one side" and the right side of FIG. 2 may be referred to as "the other side".
The rotating shaft 61 is, for example, a solid columnar member. It can be exemplified that the main magnet 62 is a cylindrical magnet magnetized in two poles.

The stator 70 includes a coreless coil 71, a cylindrical stack 72 that holds the coreless coil 71, a relay board 73 provided on the other end surface of the stack 72, and a lead wire 74 connected to the relay board 73. have.
The housing 80 includes a cylindrical case 81 in which both ends in the axial direction of the rotating shaft 61 are open, a one-side plate 82 that covers one side opening in the case 81, and a other-side plate that covers the other side opening in the case 81. It has 83 and. Further, the housing 80 is held by the one-side plate 82 and rotatably supports the one-side bearing 84 that rotatably supports one end side of the rotating shaft 61 and the other end side of the rotating shaft 61. The other side bearing 85 is provided.
The one-side plate 82 and the other-side plate 83 are substantially cylindrical members that hold the one-side bearing 84 and the other-side bearing 85 inside and are fitted inside the case 81, respectively. It can be exemplified that the one-side bearing 84 and the other-side bearing 85 are ball bearings.

The mirror 20 is attached to one end of the output shaft 61 of the motor 10 via a holding member 21. By driving the motor 10, the mirror 20 has an upper limit angle in one rotation direction (for example, clockwise; hereinafter, may be referred to as "forward direction") and a rotation direction in the opposite direction (for example, counterclockwise. Hereinafter, the mirror 20). It is rotated between the lower limit angles of (sometimes referred to as “counterclockwise”), and the laser beam incident from a laser light source (not shown) is reflected in different directions depending on the rotation angle of the output shaft 61.

The angle detector 30 is provided at the other end of the output shaft 61 of the motor 10. The angle detector 30 is a sensor for detecting the rotation angle of the output shaft 61 (mirror 20), such as the position converter described in Japanese Patent Application No. 2013-070399 filed by the applicants. Can be exemplified. The angle detector 30 outputs a voltage signal corresponding to the rotation angle of the output shaft 61 of the motor 10.

<First Embodiment>
FIG. 3 is an example of a block diagram showing the configuration of the control device 100 according to the first embodiment.
The control device 100 is an arithmetic logical operation circuit including a CPU, a ROM, a RAM, an EEPROM (Electrically Erasable & Programmable Read Only Memory), and the like.
The control device 100 uses an angle feedback (hereinafter, feedback) using the deviation between the angle command value supplied from the outside and the rotation angle detected by the angle detector 30 (hereinafter, may be referred to as “detected rotation angle”). May be referred to as "F / B".) It has an angle control unit 110 for controlling. Further, the control device 100 has a speed control unit 120 that performs speed F / B control using the output value from the angle control unit 110. Further, the control device 100 has a current control unit 130 that controls the current F / B using the output value from the speed control unit 120.

Further, the control device 100 has a drive circuit 140 that generates a drive current corresponding to a drive signal from the current control unit 130 and supplies the drive current to the motor 10.
Further, the control device 100 has a current detection unit 150 that outputs a value corresponding to the actual current actually flowing through the motor 10. The current detection unit 150 detects the value of the actual current flowing through the motor 10 from the voltage generated across the so-called shunt resistor connected to the winding of the motor 10.

(Angle control unit 110)
The angle control unit 110 has an angle deviation calculation unit 111 that obtains an angle deviation between an angle command value supplied from the outside and a detected rotation angle, and performs F / B processing so that the angle deviation becomes zero, and performs F / B processing to achieve a target rotation speed. It has a target speed setting unit 112 for setting.
The angle deviation calculation unit 111 calculates the angle deviation by subtracting the detected rotation angle from the angle command value supplied from the outside, and outputs the angle deviation to the target speed setting unit 112.
The target speed setting unit 112 performs F / B control so that the angle command value and the detected rotation angle match. For example, the angle deviation is integrated with a predetermined integration time constant, and the target rotation speed is set. Is calculated, and the calculated target rotation speed is output to the speed control unit 120.
As described above, the angle control unit 110 functions as an example of the angle control means for setting the target rotation speed by performing the angle F / B processing so that the deviation between the target rotation angle and the detected rotation angle becomes zero.

(Speed control unit 120)
The speed control unit 120 is a rotation speed calculation means for calculating an actual rotation speed corresponding to the actual rotation speed of the motor 10 from the detected rotation angle by using a correction value according to the rotation angle of the motor 10 that swings the mirror 20. As an example, it has a rotation speed calculation unit 160.
Further, the speed control unit 120 has a speed deviation calculation unit 121 that calculates a speed deviation between the target rotation speed output from the angle control unit 110 and the actual rotation speed calculated by the rotation speed calculation unit 160.
Further, the speed control unit 120 has a target current setting unit 122 as an example of a setting means for setting a target current to be supplied to the motor 10 by using the speed deviation calculated by the speed deviation calculation unit 121.

The rotation speed calculation unit 160 includes a differential compensation unit 161 that differentially compensates the rotation angle (detected rotation angle) detected by the angle detector 30, and a constant correction unit 162 that corrects the value output from the differential compensation unit 161. doing.
The differential compensation unit 161 outputs the value obtained by multiplying the differential value obtained by differentiating the detected rotation angle and the predetermined differential compensation constant to the constant correction unit 162.
The constant correction unit 162 includes a correction value determination unit 163 that determines the correction value, and an addition unit 164 that adds the correction value determined by the correction value determination unit 163 and the output value from the differential compensation unit 161. ..

FIG. 4 is a schematic view of a control map showing an example of the relationship between the detected rotation angle and the correction value.
The correction value determination unit 163 calculates a correction value according to the detected rotation angle. The correction value determination unit 163 is, for example, a control map illustrated in FIG. 4 showing the relationship between the detected rotation angle and the correction value, which is created in advance based on an empirical rule and recorded in a ROM, or an example in FIG. The correction value is calculated by substituting the detected rotation angle into the function having the above relationship, or the analog multiplier is used based on the theory that the decrease curve of the torque constant is approximated by the curve of the quadratic function. The square of the detected rotation angle is calculated, and the correction value is calculated by multiplying the value obtained by this calculation by a predetermined coefficient.

In the control map illustrated in FIG. 4, the relationship between the detected rotation angle and the correction value is defined as follows.
Here, when the rotation angle of the mirror 20 (output shaft 61 of the motor 10) corresponding to the center of the swing range of the mirror 20 is set as the reference angle, the reference is made in both the forward direction and the reverse direction. The torque constant of the motor 10 decreases as the difference in rotation angle from the angle increases. That is, as shown by the broken line in FIG. 4, when the ratio of the torque constant at each rotation angle to the torque constant at the reference angle is shown, it becomes a convex arc-shaped curve having 1 as the apex.

The relationship between the detected rotation angle and the correction value is the value of the correction value at the reference angle so that the characteristic is opposite to the characteristic of the torque constant shown by the broken line in FIG. 4, as shown by the solid line in FIG. It becomes a concave arc-shaped curve having 0 as the apex. That is, the correction value is set so as to increase as the difference in rotation angle from the reference angle increases in both the forward direction and the reverse direction.

The addition unit 164 adds the correction value determined by the correction value determination unit 163 and the output value from the differential compensation unit 161.
The rotation speed calculation unit 160 configured as described above outputs the value obtained by adding the correction values by the addition unit 164 to the speed deviation calculation unit 121 as the actual rotation speed.

The speed deviation calculation unit 121 calculates the speed deviation by subtracting the actual rotation speed calculated by the rotation speed calculation unit 160 from the target rotation speed output from the angle control unit 110, and sets the calculated speed deviation as the target current. Output to unit 122.
The target current setting unit 122 performs F / B control so that the target rotation speed output from the angle control unit 110 and the actual rotation speed calculated by the rotation speed calculation unit 160 match, for example, the speed. The target current is calculated by multiplying the speed deviation calculated by the deviation calculation unit 121 by the speed F / B gain, which is a predetermined constant. It should be noted that the predetermined constant can be exemplified as a value determined according to the specifications of the motor 10 and the shape and size of the mirror 20. The output value from the target current setting unit 122 is, in other words, the torque command value of the motor 10.

(Current control unit 130)
The current control unit 130 has a current deviation calculation unit 131 that calculates the current deviation between the target current output from the speed control unit 120 and the actual current detected by the current detection unit 150, and the current deviation is set to zero. It has a current F / B processing unit 132 that performs F / B processing.
The current deviation calculation unit 131 calculates the current deviation by subtracting the actual current detected by the current detection unit 150 from the target current output from the speed control unit 120, and transfers the current deviation to the current F / B processing unit 132. Output.
The current F / B processing unit 132 performs F / B control so that the target current and the actual current match. For example, the current deviation is multiplied by the current F / B gain, which is a predetermined constant. A drive signal corresponding to the obtained value is output to the drive circuit 140. It should be noted that the predetermined constant can be exemplified as a value determined according to the specifications of the motor 10 and the shape and size of the mirror 20. Further, the current F / B processing unit 132 may output a drive signal corresponding to the value obtained by integrating the current deviation with a predetermined integration time constant to the drive circuit 140.

(Action / effect of control device 100)
The control device 100 of the galvano scanner 1 configured as described above reduces the torque due to the fluctuation of the torque constant (see the broken line in FIG. 4) due to the difference in the rotation angle (swing angle) of the motor 10 (mirror 20). The feature is that the correction function is built in the rotation speed calculation unit 160 in the servo loop. As a result of diligent research by the present inventors, the function of correcting the torque decrease due to the fluctuation of the torque constant is built in the rotation speed calculation unit 160 in the servo loop, and as a result, all of them are obtained. This is based on the finding that the same level of scanner responsiveness can be obtained even in the swing range.

Then, in the control device 100 according to the first embodiment, the constant correction unit 162 of the rotation speed calculation unit 160 of the speed control unit 120 corrects the output value from the differential compensation unit 161. Therefore, the rotation speed calculation unit 160 calculates the actual rotation speed corresponding to the actual rotation speed of the motor 10 from the detected rotation angle by using the correction value according to the rotation angle of the motor 10 that swings the mirror 20. It functions as a rotation speed calculation means. Then, the speed deviation calculation unit 121 as an example of the deviation calculation means calculates the speed deviation between the target rotation speed and the actual rotation speed calculated by the rotation speed calculation unit 160. Then, the target current setting unit 122 as an example of the setting means sets the target current to be supplied to the motor 10 by using the speed deviation calculated by the speed deviation calculation unit 121. In this way, the speed control unit 120 sets the target current using the actual rotation speed after correction using the correction value according to the rotation angle of the motor 10, so that the mirror can be mirrored even at all swing angles. The angle of 20 can be quickly adjusted to the target angle.

FIG. 5A is a measurement result when the mirror 20 is positioned by using the control device 100 according to the first embodiment. FIG. 5B is a measurement result when the mirror 20 is positioned using the control device according to the comparative example. The control device according to the comparative example is different from the control device 100 in that it does not have the constant correction unit 162. Further, in FIGS. 5A and 5B, the position signal from the angle detector 30 when positioning the mirror 20 at a position of 16 degrees in the positive direction is shown by a solid line, and the current from the current detection unit 150 is shown. It is a figure which shows a signal by a broken line.
When the control device according to the comparative example is used, both ends of the swing range of the mirror 20 are set even if the compensation circuit in the control device is set so that an overshoot does not occur near the center of the swing range of the mirror 20. As shown in FIG. 4, the torque constant decreases toward the direction of the mirror 20, so that an overshoot occurs near both ends of the swing range of the mirror 20 as shown in FIG. 5 (b). On the other hand, when the control device 100 according to the first embodiment is used, the decrease in the torque constant near both ends of the swing range of the mirror 20 is suppressed, so that the swing range of the mirror 20 is increased. As shown in FIG. 5A, overshoot does not occur even in the vicinity of both ends. As a result, according to the control device 100 according to the first embodiment, the mirror 20 can be positioned at the target angle more quickly than the control device according to the comparative example, and the responsiveness can be improved. Further, FIGS. 5A and 5B show measurement results when the mirror 20 is positioned at a position of 16 degrees in the positive direction, but the control device 100 according to the first embodiment shows the measurement results. According to this, the angle of the mirror 20 can be quickly adjusted to the target angle even at all the swing angles.

<Second embodiment>
FIG. 6 is an example of a block diagram showing the configuration of the control device 200 according to the second embodiment.
The control device 200 according to the second embodiment is different from the control device 100 according to the first embodiment in the speed control unit 220 corresponding to the speed control unit 120. Hereinafter, the differences from the control device 100 will be described. The control device 100 and the control device 200 having the same function are designated by the same reference numerals, and detailed description thereof will be omitted.

The speed control unit 220 is provided with the rotation speed calculation unit 260 corresponding to the rotation speed calculation unit 160, the speed deviation calculation unit 221 corresponding to the speed deviation calculation unit 121, and the target current setting unit 122 with respect to the speed control unit 120. It is different from the corresponding target current setting unit 270.

The rotation speed calculation unit 260 includes a differential compensation unit 161 and a constant correction unit 162, as well as a proportional compensation unit 265 that proportionally compensates the detected rotation angle. Further, the rotation speed calculation unit 260 has an integral compensation unit 266 that integrates and compensates the actual current detected by the current detection unit 150, and a differential compensation unit 267 that differentially compensates the output value from the integral compensation unit 266. There is.

The proportional compensation unit 265 outputs a value obtained by multiplying the detected rotation angle by a predetermined proportional compensation constant to the speed deviation calculation unit 221.
The integration compensation unit 266 outputs a value obtained by incompletely integrating the actual current detected by the current detection unit 150 with a predetermined integration time constant to the differential compensation unit 267.
The differential compensation unit 267 outputs the value obtained by differentiating the value output from the integral compensation unit 266 with a predetermined differential time constant to the speed deviation calculation unit 221. The differential compensation unit 267 is for offsetting the frequency of the value output from the integral compensation unit 266, and the integral compensation unit 266 and the differential compensation unit 267 perform control compensation in a specific frequency band.

The rotation speed calculation unit 260 configured as described above adds the value output from the addition unit 164, the value output from the proportional compensation unit 265, and the value output from the differential compensation unit 267. The obtained value is output to the speed deviation calculation unit 221 as the actual rotation speed. The value output from the proportional compensation unit 265 mainly becomes the value of the rotation speed in the low frequency region, and the value output from the differential compensation unit 267 mainly becomes the value of the rotation speed in the high frequency region. Further, the value output from the addition unit 164 is a value in the middle frequency region between the low frequency region of the value output from the proportional compensation unit 265 and the high frequency region of the value output from the differential compensation unit 267. Become. Therefore, the rotation speed calculation unit 260 can calculate the actual rotation speed in a wide frequency range.
The rotation speed calculation unit 260 adds the value output from the addition unit 164, the value output from the proportional compensation unit 265, and the value output from the differential compensation unit 267 at a predetermined ratio. The value obtained by doing so may be used as the actual rotation speed. It should be noted that the predetermined ratio can be exemplified as a value determined according to the specifications of the motor 10 and the shape and size of the mirror 20.

The speed deviation calculation unit 221 calculates the speed deviation by subtracting the actual rotation speed calculated by the rotation speed calculation unit 260 from the target rotation speed output from the angle control unit 110, and calculates the calculated speed deviation as the target current. Output to the setting unit 270. That is, the speed deviation calculated by the speed deviation calculation unit 221 is the value output from the addition unit 164, the value output from the proportional compensation unit 265, and the differential compensation unit 267 from the target rotation speed output from the angle control unit 110. It is a value obtained by subtracting the value obtained by adding the value output from.
The speed deviation calculation unit 221 adds the target rotation speed output from the angle control unit 110 and the actual rotation speed calculated by the rotation speed calculation unit 260 at a predetermined ratio to obtain the speed deviation. You may calculate. It should be noted that the predetermined ratio can be exemplified as a value determined according to the specifications of the motor 10 and the shape and size of the mirror 20.

The target current setting unit 270 is a speed F / B processing unit 271 that performs F / B processing so that the speed deviation calculated by the speed deviation calculation unit 221 becomes zero, and a value output from the speed F / B processing unit 271. Has a filter 272 that performs a filtering process on the
The speed F / B processing unit 271 performs F / B control so that the target rotation speed output from the angle control unit 110 and the actual rotation speed calculated by the rotation speed calculation unit 260 match, for example. , The value obtained by multiplying the speed deviation by the speed F / B gain, which is a predetermined constant, is output to the filter 272.

The filter 272 performs a filtering process corresponding to the notch filter on the value output from the speed F / B processing unit 271. The filter 272 attenuates only signals of a certain range of frequencies and passes signals of other frequencies. In this embodiment, the filter 272 removes only the resonant frequency component of the mirror 20. Similarly, the target current setting unit 122 according to the first embodiment also resonates with the mirror 20 among the values obtained by multiplying the speed deviation calculated by the speed deviation calculation unit 121 by the speed F / B gain. Filtering processing may be performed by the filter 272 so as to remove only the frequency component.

When the control device 200 configured as described above is used, overshoot does not occur as in the case of using the control device 100 according to the first embodiment. As a result, according to the control device 200, the mirror 20 can be positioned at the target angle more quickly at all the swing angles than the control device according to the comparative example, and the responsiveness can be improved.

<Third embodiment>
FIG. 7 is an example of a block diagram showing the configuration of the control device 300 according to the third embodiment.
The control device 300 according to the third embodiment is different from the control device 200 according to the second embodiment in the target current setting unit 370 corresponding to the target current setting unit 270. Hereinafter, the differences from the control device 200 will be described. The control device 200 and the control device 300 having the same function are designated by the same reference numerals, and detailed description thereof will be omitted.

The target current setting unit 370 has a target rotation speed output from the angle control unit 110, a value output from the addition unit 164, a value output from the proportional compensation unit 265, and a value output from the differential compensation unit 267. It has an addition processing unit 371 for adding and a filter 272.
The addition processing unit 371 has a target rotation speed output from the angle control unit 110, a value output from the addition unit 164, a value output from the proportional compensation unit 265, and a value output from the differential compensation unit 267. , Are added at a predetermined ratio (for example, a ratio determined according to the shape of the mirror 20), amplified, and output to the filter 272. It should be noted that the predetermined ratio can be exemplified as a value determined according to the specifications of the motor 10 and the shape and size of the mirror 20.
Then, the filter 272 removes only the resonance frequency component of the mirror 20 from the output from the addition processing unit 371, and outputs it to the current control unit 130 as a target current of the motor 10, in other words, a torque command value.

The control device 300 configured as described above performs angle feedback processing so that the deviation between the target rotation angle and the detected rotation angle, which is the rotation angle of the motor 10 that swings the detected mirror 20, becomes zero. The angle control unit 110 as an example of the control means and the differential compensation unit 161 as an example of the differential compensation means for multiplying the value obtained by differentiating the detected rotation angle by a predetermined differential compensation constant are provided. Further, the control device 300 has a constant correction unit 162 as an example of a correction means for correcting an output value from the differential compensation unit 161 using a correction value according to the rotation angle of the motor 10, and an angle control unit 110. The target current setting unit 370 and the target current setting unit 370 as an example of the setting means for setting the target current to be supplied to the motor 10 by adding and amplifying the output value and the output value from the constant correction unit 162 at a predetermined ratio. , Equipped with. It should be noted that the predetermined ratio can be exemplified as a value determined according to the specifications of the motor 10 and the shape and size of the mirror 20.
Further, as in the control device 300, the target current setting unit 370 may add and amplify the value obtained by multiplying the detected rotation angle by a predetermined proportional compensation constant at a predetermined ratio. good. It should be noted that the predetermined ratio can be exemplified as a value determined according to the specifications of the motor 10 and the shape and size of the mirror 20. Further, the target current setting unit 370 incompletely integrates the detected current of the motor 10 with a predetermined integration time constant, and also predetermined a value obtained by differentiating with a predetermined differential time constant. You may add and amplify at the same ratio. It should be noted that the predetermined ratio can be exemplified as a value determined according to the specifications of the motor 10 and the shape and size of the mirror 20.

The measurement result when the mirror 20 is positioned at a position of 16 degrees in the positive direction by using the control device 300 configured as described above is as shown in FIG. 5A, and an overshoot occurs. There wasn't. Therefore, according to the control device 300, the mirror 20 can be positioned at the target angle more quickly at all the swing angles than the control device according to the comparative example, and the responsiveness can be improved.

<Fourth Embodiment>
FIG. 8 is an example of a block diagram showing the configuration of the control device 400 according to the fourth embodiment.
The control device 400 according to the fourth embodiment is different from the control device 100 according to the first embodiment in the speed control unit 420 corresponding to the speed control unit 120. Hereinafter, the differences from the control device 100 will be described. The control device 100 and the control device 400 having the same function are designated by the same reference numerals, and detailed description thereof will be omitted.

The speed control unit 420 considers the fluctuation amount of the torque constant with the value output from the target current setting unit 122 in addition to the rotation speed calculation unit 160, the speed deviation calculation unit 121, and the target current setting unit 122. It has a constant correction unit 423 for correction.
The constant correction unit 423 adds the correction value determination unit 424 that determines the correction value as the second correction value, the current correction value determined by the correction value determination unit 424, and the output value from the target current setting unit 122. It has a part 425 and.

The correction value determination unit 424 calculates the current correction value according to the detected rotation angle. The correction value determination unit 424 substitutes the detected rotation angle into, for example, a control map or a function showing the relationship between the detected rotation angle and the current correction value, which is created in advance based on an empirical rule and recorded in the ROM. By doing so, the current correction value is calculated.
The relationship between the detected rotation angle and the current correction value is the value of the current correction value at the reference angle so that the characteristics are opposite to the characteristics of the torque constant shown by the broken line in FIG. 4, as shown by the solid line in FIG. It becomes a concave arc-shaped curve having 0 as the apex. That is, the current correction value is set so as to increase as the difference in rotation angle from the reference angle increases in both the forward direction and the reverse direction.

In the control device 400 configured as described above, the constant correction unit 423 corrects the output value from the target current setting unit 122. Therefore, the angle of the mirror 20 can be quickly adjusted to the target angle at all swing angles.
The constant correction unit 423 that corrects the value output from the target current setting unit 122 in consideration of the fluctuation amount of the torque constant is controlled by the control device 200 according to the second embodiment and the control according to the third embodiment. It may be applied to the device 300. As a result, the angle of the mirror 20 can be quickly adjusted to the target angle at all swing angles.

1 ... Galvano scanner, 10 ... Motor, 20 ... Mirror, 30 ... Angle detector, 100, 200, 300, 400 ... Control device, 110 ... Angle control unit, 120, 220, 420 ... Speed control unit, 121,221 ... Speed deviation calculation unit, 122, 270, 370 ... target current setting unit, 130 ... current control unit, 140 ... drive circuit, 150 ... current detection unit, 160, 260 ... rotation speed calculation unit, 161 ... differential compensation unit, 162 423 ... Constant correction unit, 163,424 ... Correction value determination unit, 164,425 ... Addition unit, 265 ... Proportional compensation unit, 266 ... Integral compensation unit, 267 ... Differential compensation unit, 371 ... Addition processing unit

Claims (10)

Rotation speed calculation that calculates the actual rotation speed corresponding to the actual rotation speed of the motor from the detected rotation angle, which is the detected rotation angle of the motor, using the correction value according to the rotation angle of the motor that swings the mirror. Means and
Deviation calculation means for calculating the deviation between the target rotation speed and the actual rotation speed calculated by the rotation speed calculation means, and
A setting means for setting a target current to be supplied to the motor using the deviation calculated by the deviation calculation means, and a setting means.
A control device comprising. The control device according to claim 1, wherein the rotation speed calculation means calculates the actual rotation speed by using a differential value obtained by differentiating the detected rotation angle and the correction value. The control device according to claim 2, wherein the rotation speed calculation means calculates the actual rotation speed by using a value obtained by multiplying the detected rotation angle by a predetermined constant. The control according to any one of claims 1 to 3, further comprising an angle control means for setting the target rotation speed by performing angle feedback processing so that the deviation between the target rotation angle and the detected rotation angle becomes zero. apparatus. The control device according to any one of claims 1 to 4, wherein the setting means also uses a second correction value according to the rotation angle of the motor to set the target current. An angle control means that performs angle feedback processing so that the deviation between the target rotation angle and the detected rotation angle, which is the rotation angle of the motor that swings the detected mirror, becomes zero.
A differential compensation means for multiplying a value obtained by differentiating the detected rotation angle by a predetermined constant,
A correction means for correcting an output value from the differential compensation means using a correction value according to the rotation angle of the motor, and a correction means for correcting the output value from the differential compensation means.
A setting means for setting a target current to be supplied to the motor by adding the output value from the angle control means and the output value from the correction means at a predetermined ratio, respectively.
A control device comprising. The control device according to claim 6, wherein the setting means also adds a value obtained by multiplying the detected rotation angle by a predetermined constant at a predetermined ratio. The setting means incompletely integrates the detected current of the motor with a predetermined integration time constant, and adds a value obtained by differentiating with a predetermined differential time constant at a predetermined ratio. The control device according to claim 7. Using the correction value according to the rotation angle of the motor that swings the mirror, the actual rotation speed corresponding to the actual rotation speed of the motor is calculated from the detected rotation angle, which is the detection rotation angle of the motor.
Calculate the deviation between the target rotation speed and the actual rotation speed,
The deviation is used to set the target current to be supplied to the motor.
Control method. Angle feedback processing is performed so that the deviation between the target rotation angle and the detected rotation angle, which is the rotation angle of the motor that swings the detected mirror, becomes zero.
The value obtained by differentiating the detected rotation angle is multiplied by a predetermined constant for differential compensation.
Using the correction value according to the rotation angle of the motor, the value after the differential compensation is corrected.
The output value after the angle feedback process and the output value after correction using the correction value are added at predetermined ratios to set a target current to be supplied to the motor.
Control method.

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