JPH10127078A - Linear servo system and method for detecting pole position - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain high resolution by employing a positional signal outputted from a linear scale, i.e., pulses of phases A and B, as a positional feedback amount and employing a speed data calculated through an interpolation/data generating means as a speed feedback amount for speed control. SOLUTION: A command voltage is applied through a position control means 11, a speed control means 12 and a current control means 13 to a linear motor 6 which is thereby driven and the shifted position thereof is detected by means of a linear scale 1. A position feedback amount for positional control employs a positional signal outputted from the linear scale 1, i.e., pulses of A, B pulses, whereas a speed feedback amount for speed control employs a data obtained by interpolating an analog sine and cosine signals outputted from the linear scale 1 through an interpolation/data generating means 14. Since positional resolution is not limited, speed and acceleration components can be detected with high resolution and a servo system excellent in response can be configured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear servo system having a linear motor and a linear scale, and a method of detecting a magnetic pole position of the linear servo system.

[0002]

2. Description of the Related Art FIG. 22 is a diagram showing control blocks of a conventional linear servo control device. In the figure, 101 is
A position command P.S given from a host controller or the like (not shown). CMD and a position feedback amount P. output by a linear scale (not shown). FB and the speed command V.V. The position control means 102 for calculating and outputting the CMD outputs the speed command V.V. CMD and a position feedback amount P. from a linear scale (not shown). FB
Of the velocity feedback obtained by differentiating FB based on the amount of difference from the current command I.FB. The speed control means 103 for generating the CMD generates the current command I.D. I. Current feedback amount obtained by sampling the current flowing through the CMD and a servo motor (not shown). This is current control means for performing current control based on the difference from FB.

The current control means 103 generates a voltage command and applies a voltage to the servomotor, so that an actual current (hereinafter, referred to as an actual current) flows. However, the generated torque at this time is proportional to the current. Multiplied by the torque constant Kt is the actual generated torque (hereinafter, referred to as the actual torque). This is divided by the weight M of the servo motor and the load, and the acceleration is obtained. Location (hereafter,
Actual position). The above-described position control, speed control, and current control are usually executed at regular intervals by software using a microprocessor or the like.

In the above description, the position feedback amount P. FB is differentiated to obtain the speed feedback amount V.V. An example in which the FB is obtained has been described. Here, considering the speed resolution, the lower the position resolution and the shorter the processing cycle, the coarser the speed resolution becomes. For example, when a position detector having a low resolution is used, or when the calculation cycle is shortened in order to increase the servo performance, the speed resolution becomes coarse.

In general, a rotary motor encoder used in a machine tool has a resolution of 100,000 pulses per rotation, and is a machine directly connected with a ball screw of 10 mm. Assuming that the operation cycle is 222 μsec, the resolution of velocity feedback per position feedback pulse is 27 m.
m / min.

On the other hand, a linear scale having a resolution of 1 μm is generally used. If the speed calculation cycle is set to 222 μsec as described above, the speed resolution becomes 27 μm.
The value was 0 mm / min, which is an order of magnitude larger than that of the rotary motor encoder.

FIG. 23 is a diagram showing control blocks of a conventional linear servo controller including disturbance correction. However, the position control and the speed control are the same as in FIG. 22, and the description is omitted. Unlike the ball screw drive, the linear servo has a configuration in which a disturbance Td component is directly applied to the motor. Therefore, it is essential to improve the performance of suppressing the impact load and the like, and the following processing is performed.

Since it is necessary to calculate the acceleration to perform the torque control, the position feedback amount P. FB
Is differentiated twice and the expected torque constant Ktc and weight Mc are back-calculated to obtain a current value Ic from which the torque disturbance Td has been removed. The current value Ic and the current command I.I.
CMD is compared, the difference amount is multiplied by a correction gain Kd, and added to the current command to perform disturbance correction. However, since the differential is performed twice in order to calculate the acceleration, the machine must be treated as an excitation source.

[0009] Unlike a ball screw drive, in which the amount of inertia can be reduced by a reduction mechanism such as a gear, and the influence of the weight of the work is small, in a linear servo, the weight of the work is directly related to the speed loop gain. However, when the speed resolution is coarse, torque ripple corresponding to the speed resolution occurs in the current command, and ripple also occurs in the actual torque. The gain / speed gain could not be increased.

[0010] Furthermore, encoders for rotary motors having a resolution of one million pulses per rotation have come to be used. In order to realize an ultra-high-speed and ultra-acceleration system in a linear servo, the servo performance has been improved. Was desired.

FIG. 24 is a diagram showing a positional relationship for magnetic pole position detection in a conventional linear servo system. The figure shows an example in which the stator side is a magnet and the mover side is a coil.A certain signal generation source is provided on the stator side, and a mechanism or an electrical device for receiving this generated signal is provided on the mover side. ,
Transmit to servo controller. Let the magnetic poles of the stator be a, b, c
The detection is performed on the mover side using the three types of pulse signals described above. The accuracy of magnetic pole position detection is as shown in FIG.
The electrical angle is 60 °, which is obtained by dividing ° into six. However, this signal is different from the position feedback signal.

[0012]

SUMMARY OF THE INVENTION FB is the position feedback amount P. Since the FB is obtained by differentiating the FB, there is a problem that the speed resolution becomes coarse.

In a synchronous servomotor using a permanent magnet, it is necessary to detect the position of a magnetic pole. In a rotary motor, the magnetic pole position can be automatically detected by adjusting the reference pulse positions of the motor and a detector such as an encoder attached behind the motor at the time of manufacturing. However, in the case of a linear motor, the distance between the motor and the scale (detector) is long, and the motor and the scale are not integrated. Therefore, the position of the scale does not match the magnetic pole of the motor, and a special detection mechanism for magnetic pole detection and There is a problem that a circuit is required.

Further, the accuracy of magnetic pole position detection is 60 electrical angles.
° and coarse.

The present invention has been made to solve the above-described problems, and a first object is to obtain a high-resolution linear servo system.

A second object is to provide a linear servo system that can easily detect a magnetic pole.

Further, a third object is to obtain a linear servo system with a high accuracy of magnetic pole position detection.

[0018]

A linear servo system according to the present invention comprises a linear scale for outputting A and B phase pulses as position signals and an analog positive cosine wave, and an analog positive output from the linear scale. Data interpolation / data conversion means for interpolating a cosine wave and calculating velocity data, wherein the position feedback amount uses an A / B-phase pulse as a position signal output from a linear scale and is used for velocity control. The velocity feedback amount uses velocity data calculated by interpolation / data conversion means.

A linear scale for outputting A and B phase pulses as position signals and an analog positive cosine wave;
The analog positive cosine wave output from the linear scale is interpolated to calculate the speed data, and the position is calculated from the speed data and the position data obtained by counting the A and B-phase pulses as the position signals output from the linear scale. Speed detection / position data synthesizing means for synthesizing data, the position data synthesized by the speed detection / position data synthesizing means as the position feedback amount, and the speed detection / position data synthesizing as the speed feedback amount for speed control. The speed data calculated by the means is used.

Further, the difference between the accumulated value of the speed accumulated position where the speed data is accumulated and the accumulated position of the position accumulated where the position data is accumulated is always monitored, and an alarm is generated when the difference between the accumulated values exceeds a certain value. It is.

Further, a linear motor, a linear scale for outputting A and B phase pulses as position signals and an analog positive cosine wave, a servo control device for controlling the linear motor, and an analog positive cosine wave are interpolated. Speed detection / position data synthesizing means for synthesizing position data from speed data with high resolution and synthesizing position data from the speed data and position data obtained by counting A and B phase pulses as position signals output from the linear scale; The speed data and the position data are converted into serial data and transmitted to the servo control device.The motor data and the machine information are input into a serial data. , A servo control device, and a linear servo I / F device for transmission.

A magnetic pole position detecting method for a linear servo system according to the present invention comprises a linear motor, absolute position data,
An absolute position detection linear scale that outputs A and B phase pulses as position signals and an analog positive cosine wave;
The DC voltage command applied to the linear motor is changed according to the mechanical load.

Also, a linear motor, absolute position data,
An absolute position detection linear scale that outputs A and B phase pulses as position signals and an analog positive cosine wave;
When power is turned on, DC excitation is performed with a constant voltage command,
Creating a magnetic pole position based on the absolute position of the stopped position, energizing again, and moving to the right and left,
The method includes a step of storing the absolute position of the stopped position, and a step of creating a true magnetic pole position with the center of the stored absolute position when moving to the right and the absolute position when moving to the left.

Further, a linear motor used as a vertical axis, a brake for braking the linear motor, an absolute position detecting linear motor for outputting absolute position data, A and B phase pulses as position signals, and an analog positive cosine wave. A scale and a magnetic pole position detection method of a linear servo system comprising: a step of performing excitation by a constant DC excitation pattern by a voltage command of an excitation force smaller than a holding force of the brake while applying a brake on the vertical axis, confirming the direction of the q-axis current, and reversing the excitation phase in the case of a descending direction.

Further, a linear motor, an absolute position detecting linear scale for outputting absolute position data, A and B phase pulses as position signals, and an analog positive cosine wave,
In the magnetic pole position detection method of the linear servo system provided with, the DC excitation is performed at a constant voltage command, and if the detected phase current is larger than a specified value, the excitation voltage command is reduced and the DC excitation is performed again. Is what you do.

A linear motor and A and B as position signals
A relative position detection linear scale that outputs a phase pulse and an analog positive cosine wave, and a magnetic pole position detection method for a linear servo system, the method comprising: Checking the direction, storing the incremental count value of the stopped position, changing the excitation pattern and performing DC excitation with different voltage commands, checking the moving direction of the linear motor, and controlling the linear motor. If the moving direction of the linear motor is opposite to the moving direction of the linear motor before the excitation pattern is changed, a step of detecting the magnetic pole position based on the stored stop position, and If the moving direction is the same as the moving direction of the linear motor, the incremental count value of the stop position is stored, and this storage is performed. And detecting the magnetic pole position based on incremental count value of the stop position, and has a.

In a magnetic pole position detecting method of a linear servo system comprising a linear motor and a relative position detecting linear scale for outputting A and B phase pulses as position signals and an analog positive cosine wave, a direct current excitation is used. A step of calculating the magnetic pole reference position, and a step of performing reciprocating operation and correcting the reference position while checking the balance of the peak current required for acceleration / deceleration. And an appropriate magnetic pole reference position.

Further, in a magnetic pole position detecting method of a linear servo system including a linear motor and a relative position detecting linear scale for outputting A and B phase pulses as position signals and an analog positive cosine wave, a direct current excitation is used. Calculating a magnetic pole reference position, accelerating and decelerating in both directions, measuring a peak current during acceleration and deceleration, comparing the measured peak current during acceleration and deceleration with a reference peak value, and measuring If the peak current at the time of acceleration / deceleration is smaller than the reference peak value, the magnetic pole reference position is set to the magnetic pole reference position; and if the measured peak current at the time of acceleration / deceleration is larger than the reference peak value, the magnetic pole Adding a constant to the reference position and returning to the step of accelerating and decelerating in both directions again, wherein the measured peak current during acceleration / deceleration is smaller than the reference peak value. To Kunar, in which to repeat the steps.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1 FIG. 1 is a diagram showing a control block of a servo control device for obtaining a speed feedback amount by interpolating an analog positive cosine wave according to an embodiment of the present invention. In the figure, 1 is a linear scale that detects a mechanical position and outputs an analog positive cosine wave original signal, 3 is an analog wave transmission line that transmits an analog positive cosine wave original signal, and 4 is A and B as position signals. A and B phase pulse transmission lines for transmitting phase pulses, 6 is a linear motor, 10 is a linear servo machine equipped with the linear motor 6 and the linear scale 1, 1
1 is a position control means, 12 is a speed control means, 13 is a current control means, and 14 is an interpolation / data conversion means for obtaining an amount of speed feedback by interpolating an analog positive cosine wave.

A command voltage is applied to the linear motor 6 via the position control means 11, the speed control means 12, and the current control means 13, the linear motor 6 is driven, and the moved position is detected by the linear scale 1. The position feedback amount for position control uses A and B phase pulses as a position signal output from the linear scale 1, and the speed feedback amount for speed control is an analog positive cosine wave output from the linear scale 1. Is used by the interpolation / data conversion means 14.

FIG. 2 is a block diagram of a servo control device according to an embodiment of the present invention. In the drawing, 1 is a linear scale, 2 is a speed detecting means for performing high-resolution speed detection by interpolating an analog positive cosine wave, 3 is an analog wave transmission line, 4 is an A and B phase pulse transmission line, and 5 is an absolute position. A data transmission path, 6 is a linear motor, 7a is a servo controller for controlling the position of the linear motor 6, 8 is a numerical controller for outputting a position command to the servo controller 7, and 10 is a linear servo machine.

Next, the processing of the feedback amount will be described. When the power is turned on, the absolute position data transmitted through the absolute position data transmission line 5 is read. Thereafter, the incremental signals A, B transmitted through the A, B phase pulse transmission path 4
By counting and adding the B-phase pulse outputs, the absolute position transmitted through the absolute position data transmission line 5 at the time of turning on the power is updated to calculate the position feedback amount. As for the speed, an analog positive cosine wave transmitted through the analog wave transmission line 3 is interpolated by the speed detecting means 2 to obtain a speed feedback amount.

FIG. 3 is a flowchart for obtaining an amount of speed feedback by interpolating an analog positive cosine wave by the interpolation / data conversion means 14 according to an embodiment of the present invention. In step S101, an analog sine wave / cosine wave is simultaneously sampled and A / D converted. In step S102, the respective offset correction data SIN (OF), COS
Data SIN'θ and COS'θ from which (OF) has been removed are obtained. In step S103, the amplitude correction gain SIN (A
M), COS (AM) is multiplied by SIN'θ, COS'θ, and a sine / cosine wave SIN "of ideal amplitude having no amplitude difference
In step S104, the cosine wave side is shifted by r according to the following addition theorem, and SIN "θ, COS
COS ′ ″ θ is obtained based on S ″ θ (where r is S
It indicates that the phase difference between SINθ and COSθ deviates from 90 ° by r in the deviation angle from INθ. ) COS ′ ″ θ = COS ”θ · COSr−SIN” θ · S
INr In step S105, tan-1? Is calculated from SIN "? And COS"'?.

By this tan-1θ, the angle θ within one cycle is obtained.
n is calculated, and the current speed accumulated position is calculated by adding the current θn to the previous speed accumulated position Σθn-1.

Here, the resolution of the speed feedback amount obtained by the above-described flowchart is obtained. For example,
The resolution after quadrupling the A and B phase pulse outputs is 1 μm, while one cycle of the analog original signal is 40 μm and the 8-bit A / D
When tan-1θ is obtained by interpolation using a converter, it is possible to divide up to 9-bit accuracy.
Since the resolution is 0/512 = 0.080 μm, the resolution is about ten times that of the related art. This is 120,000 pulses / rotation as compared with the case of a direct-coupled ball screw 10 mm machine using a rotary motor.

Embodiment 2 FIG. 4 is a block diagram of a servo control device according to one embodiment of the present invention. In the figure, 1, 3 to 6, and 10 are the same as those in FIG. 2 of the first embodiment, and a description thereof will be omitted. Reference numeral 7b denotes a servo control device for controlling the position of the linear motor 6, and 15 denotes a linear servo I / O which interpolates an analog positive cosine wave to obtain high-resolution speed data, converts this data into serial data, and transmits the serial data to the servo control device 7b. / F device. In the above-described first embodiment, an example is shown in which the interpolation / data conversion means 14 is incorporated in the servo control device 7a as the speed detection means 2, but in this embodiment, the linear servo I / F device 15 performs analog positive A high-resolution speed data is obtained by interpolating a cosine wave, and this data is converted into serial data and transmitted to the servo controller 7b.

In this embodiment, the linear servo I / F
Since a high-resolution velocity data is obtained by interpolating an analog positive cosine wave by the device 15 and this data is converted into serial data and transmitted to the servo control device 7a, a dedicated servo control device is used. Unlike this, a standard servo controller can be used and the analog transmission path can be shortened, so that highly reliable speed data can be obtained.

Embodiment 3 FIG. 5 is a control block diagram of the servo control device according to the embodiment of the present invention.
In the figure, 1, 3, 4, 6, and 10 to 14 are the same as those in FIG. 2 of the first embodiment, and a description thereof will be omitted.
Numeral 16 denotes a position data synthesizing means for synthesizing position data from the velocity data calculated by the interpolation / data conversion means 14 and position data obtained by counting the A and B phase pulses as position signals output from the linear scale 1. is there.

FIG. 6 is a flowchart showing a position data synthesizing method of the position data synthesizing means 16 according to one embodiment of the present invention. In step S201, an analog positive cosine wave is interpolated to obtain high-resolution speed data Pv. In step S202, the position data P.A. and the A.B-phase pulse outputs sampled simultaneously with the sampling of the analog positive cosine wave are counted. Refer to FB. Step S20
3, the position data P. Position correction data Pc obtained by adding the reference error amount Pbe to FB is obtained. (Here, the reference error amount P
be is a data difference between the position and the speed, measured when the linear scale is used for the first time, and stored in a nonvolatile memory or the like in advance. ) Pc = P. FB + Pbe In step S204, the position correction data Pc and the speed data Pv are superimposed, and an error generated by the superimposition is Pe. (The criterion in this case is the high-precision speed side.) Subsequently, an error Pe is added to the position correction data Pc to obtain high-resolution position data Pc ′. Pe = Pc−Pv (However, | Pe | = <１ ／ pulse based on one pulse of position data P.FB) Pc ′ = Pc + Pe This position data is created every time position control / speed control is performed. Used as position information and speed information.

FIG. 7 is a block diagram of a servo control device according to an embodiment of the present invention. In the figure, 1,
3, 4, 6, and 10 are the same as those in FIG. 2 of the first embodiment, and a description thereof will be omitted. 7c is a servo control device,
A speed detecting / position data synthesizing means 17 obtains high-resolution speed data by interpolating an analog positive cosine wave and synthesizes position data. The interpolation / data converting means 14 and the position data synthesizing means 16 are built in the servo control device 7c as the speed detecting / position data synthesizing means 17.

FIG. 8 is a block diagram of a servo control device according to one embodiment of the present invention. In the figure, 1,
3, 4, 6, and 10 are the same as those in FIG. 1 of the first embodiment, and a description thereof will be omitted. 7d is a servo control device,
Reference numeral 18 denotes a linear servo I / F device that obtains high-resolution speed data by interpolating an analog positive cosine wave, synthesizes position data, converts this data into serial data, and transmits the serial data to the servo control device 7d.

An analog positive cosine wave is interpolated by the linear servo I / F device 18 to obtain high-resolution speed data and synthesize position data, and the serialized position data is transmitted to the servo control device 7d. Thus, unlike FIG. 7C which uses a dedicated servo control device, a standard servo control device can be used, and the analog transmission path can be shortened to obtain highly reliable position data. be able to.

Embodiment 4 FIG. FIG. 9 is a diagram showing the relationship between the speed accumulation position and the position accumulation position according to the embodiment of the present invention. The speed data and the position data are accumulated, and the difference between the accumulated values is constantly monitored. When the difference between the accumulated values exceeds a certain value, an alarm is issued.

Embodiment 5 FIG. FIG. 10 is a block diagram of a servo control device according to one embodiment of the present invention. In the figure, 1, 3, 4, 6, and 10 are the same as those in FIG. 1 of the first embodiment, and a description thereof will be omitted. 7e is a servo control device, 21 is a transmission path for motor information such as temperature thermal, 22 is a transmission path for mechanical information, and 23 is a linear servo I / F device.

The linear servo I / F device 23 is provided with speed detecting / position data synthesizing means for obtaining high-resolution speed data by interpolating an analog positive cosine wave and synthesizing position data, and converting the position data into serial data. In addition to the transmission to the servo control device 7c, the device includes an input portion for motor information such as temperature thermal and an input portion for machine information. The motor information and the machine information are converted into serial data and transmitted to the servo control device 7e.

Embodiment 6 FIG. FIG. 11 is a block diagram of a servo control device according to one embodiment of the present invention. In the figure, 1a is an absolute position detection linear scale, 6 is a linear motor, 7f is a servo control device, 24 is a mechanical load,
25 is a DC voltage command varying means. In the actual machine, the DC excitation performed to detect the magnetic pole position of the linear motor needs to be changed according to the mechanical load 25, and the DC voltage command varying means 25 applies the servo control device 7f to the linear motor 6 according to the parameter. Since the DC voltage command is varied, the motor is always stopped at an appropriate position.

FIG. 12 is a diagram showing the ratio of the voltage command applied to each phase when the DC voltage pattern according to the embodiment of the present invention is variably adjusted with parameters. N in the figure
O. Reference numeral 1 denotes an example in which a MAX voltage is applied to the U phase, and a voltage of -1/2 is applied to the other V and W phases. For DC excitation, the linear motor 6 stops at the position where it is magnetically attracted, but it is assumed that the adjustment position may be limited depending on the machine. In the figure, an example of six three-phase patterns is shown. It is also possible to make it possible to arbitrarily select at a finer angle level so that the vehicle can be stopped with a minimum moving distance.

FIG. 13 is a flowchart showing a magnetic pole detection method at the time of driving (at the time of initial adjustment) according to an embodiment of the present invention. In step S301, in order to detect the magnetic pole position of the synchronous linear servo motor (LSM), the motor is DC-excited in a certain pattern. Step S302
Since the motor stops at a predetermined electrical angle according to the DC excitation pattern, the absolute position counter at this position is stored as a reference magnetic pole position (MPBP) in the servo control device or its higher-level controller.

FIG. 14 is a flowchart showing a magnetic pole detection method during driving according to an embodiment of the present invention. If the magnetic pole detection shown in FIG. 13 is executed once at the time of the initial adjustment, the following flow chart is used from the next power-on.
Automatically detects magnetic pole position. In step S311, the power-on absolute position counter (ABS0) is read. In step S312, the reference magnetic pole position (MPBP) stored during the initial adjustment, the linear scale resolution (SKP (p / mm)) of the servo parameter, and the magnetic pole pitch (MPIT (m
m)), the current motor electric angle θ is obtained by the following equation. A = Remainder ((ABS0-MPBP) / (SKP * MPI)
T)) θ = (A * 360) / (SKP * MPIT) In step S313, current control is performed using the motor electrical angle θ.

Embodiment 7 FIG. FIG. 15 is a flowchart showing a magnetic pole detection method at the time of driving (at the time of initial adjustment) according to an embodiment of the present invention. In step S321, excitation is automatically performed according to a constant DC excitation pattern. In step S322, the absolute position of the stop position (MPBP0) is stored. In step S323, the motor is moved, for example, to the left by an electrical angle of 30 ° from the magnetic pole position created based on the absolute position (MPBP0) according to the flowchart of FIG.
After moving to a position shifted by about a degree, the absolute position (MPBPL) of the position where the excitation is stopped again and stopped is stored. Step S3
At 24, the absolute position (MPBPR) of the position where the motor is moved to the right (in the opposite direction to step S323) by an electrical angle of about 30 ° and then excited and stopped again is stored. In step S325, the center between the absolute position (MPBPL) stored in step S323 and the absolute position (MPBPR) stored in step S324 is set as a true magnetic pole position. True magnetic pole position MPBP = (MPBPL + MPBPR)
/ 2

Embodiment 8 FIG. FIG. 16 is a flowchart showing a magnetic pole detection method (at the time of initial adjustment) at the time of driving the vertical axis according to an embodiment of the present invention. Step S331
Therefore, the brakes of the vertical axis are kept applied. Step S
At 332, the excitation is performed according to a constant DC excitation pattern by a voltage command Vp of an excitation force smaller than the holding force of the brake. In step S333, the direction of the q-axis current is confirmed. If the direction is the rising direction, the flow proceeds to step S335. If the direction of the q-axis current is the descending direction, step S3
At 34, the excitation phase is reversed. In step S335, the voltage command Vp is gradually increased, and after confirming that it starts moving, the brake is released. In step S336, the absolute position of the stop position (MPBPP) is stored.

In the subsequent processing, current control is performed according to FIGS. In this embodiment, the DC excitation pattern is determined while applying a brake on the vertical axis or the like affected by gravity, and during the initial adjustment, it always moves upward and stops.

Embodiment 9 FIG. FIG. 17 is a flowchart showing a magnetic pole detection method at the time of driving (at the time of initial adjustment) according to an embodiment of the present invention. In step S341, DC excitation is performed with a constant voltage command Vp. In step S342,
Detect phase current. Iu, Iv, Iw (= − (Iu + Iv)) In step S343, the detected phase current is compared with a specified value. If the detected phase current is larger than the specified value, the voltage command Vp is decreased in step S344, and step S343 is performed.
Return to If the detected phase current is smaller than the specified value, the absolute position of the stop position (MPBP) is stored in step S345.

In the subsequent processing, current control is performed according to FIGS. In this embodiment, the phase current at the time of the initial adjustment is monitored, and when an excessive current is detected, the excitation voltage command is narrowed down to protect the motor from demagnetization.

Embodiment 10 FIG. FIG. 18 is a flowchart showing a magnetic pole detection method when the relative position detection linear scale according to one embodiment of the present invention is used. In step S401, the power of the servo control device is turned on.
In step S402, DC excitation is performed with a constant voltage command Vp. In step S403, the incremental count value (MPOS) of the stop position is stored. Step S40
4, based on the linear scale resolution (SKP (p / mm)), the magnetic pole pitch (MPIT (mm)), the incremental count value (MPOS) of the stop position, and the current feedback counter position MPAM, Is obtained. A = Remainder ((MPAM-MPOS) / (SKP * MPI)
T)) θ = (A * 360) / (SKP * MPIT) In step S405, current control is performed using the motor electrical angle θ.

FIG. 19 is a flowchart showing a magnetic pole detection method using a relative position detection linear scale according to one embodiment of the present invention. In FIG. 18 described above,
Although an example of DC excitation with a constant voltage command has been described, FIG. 19 shows a case in which the pattern of DC excitation is automatically changed to detect a magnetic pole. In step S411, the constant voltage command Vp
Excitation at 1 with DC. In step S412, the direction in which the motor starts to move is checked. In this flowchart, an example will be described below in which it is first checked whether the user has moved to the left. If the direction in which the motor starts to move is on the left, the process proceeds to step S418.

If the direction in which the motor starts moving is on the right side, the stopped position is stored in step S413 and the voltage command Vp
Change the excitation pattern to 6. In step S414, it is checked whether the camera has moved to the left. If the camera has moved to the left, this position is stored, and the process proceeds to step S421. If it has moved to the right, the stop position is stored in step S415,
Change to the excitation pattern of voltage command Vp5. Step S
At 416, it is checked whether the user has moved to the left. If the user has moved to the left, this position is stored, and the process proceeds to step S421.
If it has moved to the right, in step S415, the voltage command V
Change to the excitation pattern of p4, memorize the stop position,
Proceed to step S421.

If it is determined in step S412 that the direction in which the motor starts moving is on the left side, the stopped position is stored in step S418, and the excitation pattern is changed to the voltage command Vp2 excitation pattern. In step S419, it is checked whether the position has moved to the left. If the position has moved to the right, this position is stored and the process proceeds to step S421. If it has moved to the left, step S42
At 0, the excitation pattern is changed to the excitation pattern of the voltage command Vp3, the stopped position is stored, and the process proceeds to step S421.

In step S421, a magnetic pole position MPBP is calculated from the stored position and the final excitation pattern.
Hereinafter, steps S404 and S4 in FIG.
In the same manner as in step 05, the motor electric angle θ is calculated and the current control is performed. In this embodiment, the magnetic pole position is detected at the closest position while automatically changing the excitation pattern.

Embodiment 11 FIG. FIG. 20 is a diagram illustrating a state of final fine adjustment at the time of magnetic pole adjustment when the relative position detection linear scale according to one embodiment of the present invention is used.
There is a possibility that the magnetic pole position adjusted by the DC excitation has a slight shift due to a mechanical load or the like. Therefore, the reciprocating operation is performed several times at the end of the magnetic pole adjustment, and the reference position is corrected while checking the balance of the peak current required for acceleration and deceleration.
As shown in FIG.
%, There is a deviation of 90% in the right direction from 10%, and the magnetic pole reference position MPBP is calculated by the following equation: MPBP = MPBP + (AB) * Kc (where Kc is a proportional constant for MPBP adjustment) Perform acceleration / deceleration. When the convergence is achieved by several acceleration / deceleration operations, an appropriate MPBP is set.

Embodiment 12 FIG. FIG. 21 is a flowchart showing the final fine adjustment at the time of magnetic pole adjustment when the relative position detection linear scale according to one embodiment of the present invention is used. In step S501, acceleration and deceleration are performed in both directions. In step S502, Idmax during acceleration / deceleration is measured. In step S503, Idmax and the reference peak value Ipdm
ad, and Idmax is equal to the reference peak value Ipdma.
If it is smaller than x, it is OK at the current magnetic pole reference position MPBP.
And If Idmax is larger than the reference peak value Ipdmax, in step S504, the magnetic pole reference position MPBP
, And returns to step S501.

[0062]

Since the present invention is configured as described above, it has the following effects.

The linear servo system according to the present invention
A linear scale that outputs A and B phase pulses and an analog positive cosine wave as a position signal, and an analog positive cosine wave output from the linear scale to interpolate data to calculate velocity data. The position feedback amount uses A and B phase pulses as a position signal output from a linear scale, and the speed feedback amount for speed control uses the speed data calculated by the interpolation / data conversion means. Since it is used, a speed / acceleration component with a high resolution can be detected without being limited by the position resolution, so that a speed gain can be increased and a servo system with good response can be constructed.

A linear scale for outputting A and B phase pulses as position signals and an analog positive cosine wave;
The analog positive cosine wave output from the linear scale is interpolated to calculate the speed data, and the position is calculated from the speed data and the position data obtained by counting the A and B-phase pulses as the position signals output from the linear scale. Speed detection / position data synthesizing means for synthesizing data, the position data synthesized by the speed detection / position data synthesizing means as the position feedback amount, and the speed detection / position data synthesizing as the speed feedback amount for speed control. Since the speed data calculated by the means is used,
The speed resolution and the position resolution can be increased, and a highly accurate servo system can be constructed.

Further, the difference between the accumulated value of the speed accumulated position of the speed data and the accumulated position of the position accumulated position data is constantly monitored, and an alarm is issued when the difference of the accumulated value exceeds a certain value. Therefore, a servo system that can easily prevent the displacement can be constructed.

Further, a linear motor, a linear scale for outputting A and B phase pulses as position signals and an analog positive cosine wave, a servo control device for controlling the linear motor, and an analog positive cosine wave are interpolated. Speed detection / position data synthesizing means for synthesizing position data from speed data with high resolution and synthesizing position data from the speed data and position data obtained by counting A and B phase pulses as position signals output from the linear scale; The speed data and the position data are converted into serial data and transmitted to the servo control device.The motor data and the machine information are input into a serial data. And a linear servo I / F device for transmitting a servo control device. The without adding, also without providing a circuit for processing a new input unit or the signal to the servo controller side, additional features can be constructed easily servo system.

A magnetic pole position detecting method for a linear servo system according to the present invention comprises a linear motor, absolute position data,
An absolute position detection linear scale that outputs A and B phase pulses as position signals and an analog positive cosine wave;
The DC voltage command applied to the linear motor is changed according to the mechanical load, eliminating the need for a voltage supply device for DC exciting the linear motor, and detecting the proper magnetic pole position regardless of the motor characteristics or the presence or absence of gravity. Can be.

Also, a linear motor, absolute position data,
An absolute position detection linear scale that outputs A and B phase pulses as position signals and an analog positive cosine wave;
When power is turned on, DC excitation is performed with a constant voltage command,
Creating a magnetic pole position based on the absolute position of the stopped position, energizing again, and moving to the right and left,
Since it has a step of storing the absolute position of the stopped position, and a step of creating a true magnetic pole position with the center of the stored absolute position when moving to the right and the absolute position when moving to the left, Accurate magnetic pole position detection is possible.

Further, a linear motor used as a vertical axis, a brake for braking the linear motor, an absolute position detecting linear motor for outputting absolute position data, A and B phase pulses as position signals, and an analog positive cosine wave. A scale and a magnetic pole position detection method of a linear servo system comprising: a step of performing excitation by a constant DC excitation pattern by a voltage command of an excitation force smaller than a holding force of the brake while applying a brake on the vertical axis, The step of confirming the direction of the q-axis current and reversing the excitation phase in the case of the descending direction is provided, so that the magnetic pole position can be easily adjusted even with respect to the vertical axis where initial magnetic pole position adjustment is difficult.

Further, a linear motor, an absolute position detection linear scale for outputting absolute position data, A and B phase pulses as position signals, and an analog positive cosine wave,
In the magnetic pole position detection method of the linear servo system provided with, the DC excitation is performed at a constant voltage command, and if the detected phase current is larger than a specified value, the excitation voltage command is reduced and the DC excitation is performed again. I decided to
The linear motor can be protected from demagnetization during initial magnetic pole position adjustment.

A linear motor and A and B as position signals
A relative position detection linear scale for outputting a phase pulse and an analog positive cosine wave, a magnetic pole position detection method for a linear servo system, comprising: Checking, and storing the incremental count value at the stopped position; changing the excitation pattern and performing DC excitation with a different voltage command; checking the motor moving direction; and If the direction is opposite to the moving direction of the motor before the excitation pattern is changed, a step of detecting the magnetic pole position based on the stored stop position, and the moving direction of the motor is the same as the moving direction of the motor before the excitation pattern is changed. If they are the same, the incremental count value at the stop position is stored, and the incremental count at the storage stop position is stored. And detecting the magnetic pole position based on,
The magnetic pole position can be detected without greatly moving the motor.

Further, in a magnetic pole position detecting method of a linear servo system comprising a linear motor and a relative position detecting linear scale for outputting A and B phase pulses as position signals and an analog positive cosine wave, a DC excitation is used. A step of calculating the magnetic pole reference position, and a step of performing reciprocating operation and correcting the reference position while checking the balance of the peak current required for acceleration / deceleration. Since an appropriate magnetic pole reference position is set, an error in the magnetic pole reference position can be easily corrected.

Further, in a magnetic pole position detecting method of a linear servo system comprising a linear motor and a relative position detecting linear scale for outputting A and B phase pulses as position signals and an analog positive cosine wave, a DC excitation is used. Calculating a magnetic pole reference position, accelerating and decelerating in both directions, measuring a peak current during acceleration and deceleration, comparing the measured peak current during acceleration and deceleration with a reference peak value, and measuring If the peak current at the time of acceleration / deceleration is smaller than the reference peak value, the magnetic pole reference position is set to the magnetic pole reference position; and if the measured peak current at the time of acceleration / deceleration is larger than the reference peak value, the magnetic pole Adding a constant to the reference position and returning to the step of accelerating and decelerating in both directions again, wherein the measured peak current during acceleration / deceleration is smaller than the reference peak value. Until Kunar. Thus repeating the above steps can be easily corrected error of the magnetic pole reference position.

[Brief description of the drawings]

FIG. 1 is a diagram showing a control block of a servo control device for obtaining a speed feedback amount by interpolating an analog positive cosine wave according to an embodiment of the present invention.

FIG. 2 is a block diagram of a servo control device according to an embodiment of the present invention.

FIG. 3 is a flowchart for obtaining an amount of speed feedback by interpolating an analog positive cosine wave by an interpolation / data conversion unit 14 according to an embodiment of the present invention;

FIG. 4 is a block diagram of a servo control device according to one embodiment of the present invention.

FIG. 5 is a control block diagram of a servo control device according to one embodiment of the present invention.

FIG. 6 is a flowchart showing a position data synthesizing method of the position data synthesizing means 16 according to the embodiment of the present invention.

FIG. 7 is a block diagram of a servo control device according to one embodiment of the present invention.

FIG. 8 is a block diagram of a servo control device according to one embodiment of the present invention.

FIG. 9 is a diagram showing a relationship between a speed accumulation position and a position accumulation position according to the embodiment of the present invention.

FIG. 10 is a block diagram of a servo control device according to one embodiment of the present invention.

FIG. 11 is a block diagram of a servo control device according to one embodiment of the present invention.

FIG. 12 is a diagram showing a ratio of a voltage command applied to each phase when a DC voltage pattern according to an embodiment of the present invention is variably adjusted with a parameter.

FIG. 13 is a flowchart illustrating a magnetic pole detection method during driving (at the time of initial adjustment) according to an embodiment of the present invention.

FIG. 14 is a flowchart illustrating a magnetic pole detection method during driving according to an embodiment of the present invention.

FIG. 15 is a flowchart illustrating a magnetic pole detection method during driving (at the time of initial adjustment) according to an embodiment of the present invention.

FIG. 16 is a flowchart showing a magnetic pole detection method (at the time of initial adjustment) at the time of driving the vertical axis according to an embodiment of the present invention.

FIG. 17 is a flowchart illustrating a magnetic pole detection method (during initial adjustment) during driving according to an embodiment of the present invention.

FIG. 18 is a flowchart showing a magnetic pole detection method when a relative position detection linear scale according to one embodiment of the present invention is used.

FIG. 19 is a flowchart illustrating a magnetic pole detection method when a relative position detection linear scale according to an embodiment of the present invention is used.

FIG. 20 is a diagram showing a state of final fine adjustment at the time of magnetic pole adjustment when the relative position detection linear scale according to one embodiment of the present invention is used.

FIG. 21 is a flowchart showing final fine adjustment at the time of magnetic pole adjustment when the relative position detection linear scale according to one embodiment of the present invention is used.

FIG. 22 is a diagram showing control blocks of a conventional linear servo control device.

FIG. 23 is a diagram showing control blocks of a conventional linear servo control device including disturbance correction.

FIG. 24 is a diagram showing a configuration of magnetic pole position detection in a conventional linear servo system.

[Explanation of symbols]

1 linear scale, 2 speed detecting means, 3 analog wave transmission path, 4A and B phase pulse transmission path, 5 absolute position data transmission path, 6 linear motor, 7a, 7b,
7c, 7d, 7e, 7f servo controller, 8 numerical controller, 10 linear servo machine, 11 position controller, 12 speed controller, 13 current controller,
14 interpolation / data conversion means, 15 linear servo I /
F device, 16 position data synthesizing means, 17 speed detection / position data synthesizing means, 18 servo control device, 21
Transmission line for motor information, 22 Transmission line for machine information, 23 Linear servo I / F device, 24 Mechanical load, 25 DC voltage command variable means.

Claims (11)

[Claims] 1. A linear scale for outputting A and B phase pulses as position signals and an analog positive cosine wave, and an analog positive cosine wave output from the linear scale are interpolated to calculate speed data. Interpolation / data conversion means, wherein the position feedback amount uses A and B phase pulses as position signals output from the linear scale, and the speed feedback amount for speed control is the interpolation / data conversion means. A linear servo system using speed data calculated by a means. 2. A linear scale that outputs A and B phase pulses as position signals and an analog positive cosine wave, and an analog positive cosine wave output from the linear scale are interpolated to calculate velocity data and A, as the speed data and the position signal output from the linear scale,
Speed detection / position data synthesizing means for synthesizing position data from position data obtained by counting the B-phase pulse,
The position data synthesized by the speed detection / position data synthesizing means is used as the position feedback amount, and the speed data calculated by the speed detection / position data synthesizing means is used as the speed feedback amount for speed control. Linear servo system. 3. The method according to claim 1, wherein the difference between the accumulated value of the speed accumulated at the speed data and the accumulated position of the position accumulated at the position data is constantly monitored, and an alarm is generated when the difference of the accumulated value exceeds a predetermined value. The linear servo system according to claim 1 or 2, wherein: 4. A linear motor, and A,
A linear scale that outputs a B-phase pulse and an analog positive cosine wave; a servo control device that controls the linear motor; and an analog positive cosine wave interpolated to obtain high-resolution speed data. A speed detecting / position data synthesizing means for synthesizing position data from position data obtained by counting A and B phase pulses as position signals output from the scale, and converting the speed data and the position data into serial data to perform servo control. A linear servo I / F device that has an input section for motor information such as temperature thermal and an input section for machine information, converts the motor information and the machine information into serial data, and transmits the servo control device; , With a linear servo system. 5. A magnetic pole position detecting method for a linear servo system comprising: a linear motor; and an absolute position detecting linear scale for outputting absolute position data, A and B phase pulses as position signals, and an analog positive cosine wave. A method of detecting a magnetic pole position of a linear servo system that changes a DC voltage command applied to a linear motor according to a mechanical load. 6. A magnetic pole position detecting method for a linear servo system comprising: a linear motor; and an absolute position detecting linear scale for outputting absolute position data, A and B phase pulses as position signals, and an analog positive cosine wave. At the time of power-on, a step of DC excitation with a constant voltage command, and a step of creating a magnetic pole position based on the absolute position of the stopped position,
Exciting again and moving to the right and left, storing the absolute position of the stopped position, and setting the true magnetic pole position to the center of the stored absolute position when moving to the right and the absolute position when moving to the left. Creating the magnetic pole position of the linear servo system. 7. A linear motor used as a vertical axis, a brake for braking the linear motor, an absolute position detection linear for outputting absolute position data, A and B phase pulses as position signals, and an analog positive cosine wave. A scale and a magnetic pole position detection method of a linear servo system comprising: a step of performing excitation by a constant DC excitation pattern by a voltage command of an excitation force smaller than a holding force of the brake while applying a brake on the vertical axis, confirming the direction of the q-axis current and reversing the excitation phase if the current is in the descending direction. 8. A magnetic pole position detecting method for a linear servo system comprising: a linear motor; and an absolute position detecting linear scale for outputting absolute position data, A and B phase pulses as position signals, and an analog positive cosine wave. A magnetic pole position detecting method for a linear servo system, wherein DC excitation is performed with a constant voltage command, and if the detected phase current is larger than a specified value, the excitation voltage command is reduced and DC excitation is performed again. 9. A linear motor, and A,
A relative position detection linear scale that outputs a B-phase pulse and an analog positive cosine wave, and a magnetic pole position detection method of a linear servo system, comprising: A step of checking the moving direction, a step of storing an incremental count value at the stopped position, a step of changing the excitation pattern and performing DC excitation with a different voltage command, a step of checking the moving direction of the linear motor, and a step of If the moving direction of the motor is opposite to the moving direction of the linear motor before the excitation pattern is changed, the step of detecting the magnetic pole position based on the stored stop position, and the moving direction of the linear motor is changed before the excitation pattern is changed. If it is the same as the moving direction of the linear motor, the incremental count value at the stop position is stored, and Magnetic pole position detection method of linear servo system having the steps of detecting the magnetic pole position based on the count value of the stop position incremental, the. 10. A magnetic pole position detecting method for a linear servo system comprising a linear motor and a relative position detecting linear scale for outputting A and B phase pulses as position signals and an analog positive cosine wave. A step of calculating the magnetic pole reference position, and a step of performing reciprocating operation and correcting the reference position while checking the balance of the peak current required for acceleration / deceleration. A magnetic pole position detecting method for a linear servo system, wherein the magnetic pole position is set to an appropriate magnetic pole reference position. 11. A magnetic pole position detecting method for a linear servo system comprising: a linear motor; and a relative position detecting linear scale for outputting A and B phase pulses as position signals and an analog positive cosine wave. Calculating a magnetic pole reference position, accelerating and decelerating in both directions, measuring a peak current during acceleration and deceleration, comparing the measured peak current during acceleration and deceleration with a reference peak value, and measuring If the peak current during acceleration / deceleration is smaller than the reference peak value, the magnetic pole reference position is set to the magnetic pole reference position.If the measured peak current during acceleration / deceleration is larger than the reference peak value, the magnetic pole Adding a constant to the reference position, and returning to the stage of accelerating and decelerating in both directions again, wherein the measured peak current during acceleration / deceleration becomes smaller than the reference peak value. A magnetic pole position detecting method for a linear servo system, wherein the steps are repeated until the magnetic pole position is detected.