CN113366757A - Motor drive device and motor drive system - Google Patents

Motor drive device and motor drive system Download PDF

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Publication number
CN113366757A
CN113366757A CN201980090296.1A CN201980090296A CN113366757A CN 113366757 A CN113366757 A CN 113366757A CN 201980090296 A CN201980090296 A CN 201980090296A CN 113366757 A CN113366757 A CN 113366757A
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motor
value
drive
characteristic
instruction
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CN201980090296.1A
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Chinese (zh)
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青木成宪
五十岚裕司
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Mitsubishi Electric Corp
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Mitsubishi Electric Corp
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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P29/00—Arrangements for regulating or controlling electric motors, appropriate for both AC and DC motors

Abstract

To solve the problem that an estimated value of a characteristic of a motor (301) or a drive mechanism (302) greatly fluctuates due to the influence of a change in an operating condition such as a change in an operating mode, a change in a workpiece, or the implementation of an operation in which a disturbance exists during an operating operation, there are provided a motor drive device (100) and a motor drive system (1) which are provided with a characteristic estimation instruction acquisition unit (112) that acquires a characteristic estimation instruction signal (C1) that instructs whether or not to perform estimation in accordance with the operating condition from the outside of the motor drive device (100), and that does not perform estimation when the characteristic estimation instruction signal (C1) is an instruction to perform no estimation, and therefore can use the estimated value of the characteristic without being influenced by the change in the operating condition.

Description

Motor drive device and motor drive system
Technical Field
The present invention relates to a motor drive device and a motor drive system for driving a drive mechanism using a motor.
Background
A motor drive device is used to drive a drive mechanism by a motor. As the drive mechanism, for example, there is a machining table that drives and moves a ball screw, and the drive mechanism is used for a machine tool in a production line. The motor drive device estimates an estimated value of a characteristic such as friction or vibration of the motor or the drive mechanism for abnormality diagnosis and characteristic compensation.
In a conventional motor drive system, for example, a table is caused to perform a movement stopping operation for a plurality of unit movement amounts in one direction and a movement stopping operation for a plurality of unit movement amounts in the opposite direction by a drive command different from a work operation for production from a numerical control device, and friction measurement is performed to calculate a friction value. Then, for example, it is determined whether or not the friction value falls within an allowable range to perform a failure diagnosis (for example, refer to patent document 1).
In addition, in an initial stage of starting the drive mechanism, a test operation designated by the servo adjustment unit is performed to perform servo adjustment, and load characteristics are measured to compensate for the load characteristics (see, for example, patent document 2).
Patent document 1: japanese patent laid-open publication No. 2004-362204
Patent document 2: international publication No. 2014/156164
Disclosure of Invention
However, the motor drive device and the motor drive system described above have a problem that, due to changes in the operation conditions such as changes in the operation mode, changes in the type of workpiece, and execution of operation in which disturbance occurs during operation, due to the changes, estimated values of characteristics such as friction and vibration greatly change, and it becomes difficult to diagnose an abnormality, compensate characteristics, and the like.
The present invention has been made to solve the above-described problems, and an object thereof is to provide a motor drive device capable of utilizing an estimated value of a characteristic without being affected by a change in an operating condition.
The motor driving device according to the present invention includes: a drive detection value acquisition unit that acquires a drive detection value based on a position or a speed of a motor that drives a drive mechanism by the motor; a drive command acquisition unit that acquires a drive command signal that is a target value of the drive detection value; a drive control unit that performs a control operation so that the drive detection value follows the drive command signal, and causes the motor to perform a driving operation by causing a current to flow to the motor; a characteristic estimation instruction acquisition unit that acquires, from outside, a characteristic estimation instruction signal that instructs whether or not to estimate a characteristic value of the motor or the drive mechanism in accordance with an operation condition of the drive operation determined by the drive instruction signal; and a characteristic estimation unit that estimates a characteristic value based on a control state value used for control calculation by the drive control unit when the characteristic estimation instruction signal is an instruction to estimate, outputs the characteristic estimation value, and does not estimate when the characteristic estimation instruction signal is an instruction to not estimate.
ADVANTAGEOUS EFFECTS OF INVENTION
According to the present invention, it is possible to output a characteristic estimated value that is not affected by a change in operating conditions.
Drawings
Fig. 1 is a schematic configuration diagram showing a motor drive system according to embodiment 1 of the present invention.
Fig. 2 is an explanatory diagram of an operation of the motor drive system according to embodiment 1 of the present invention.
Fig. 3 is an explanatory diagram of an operation of the motor drive system according to embodiment 2 of the present invention.
Fig. 4 is a schematic configuration diagram showing a motor drive system according to embodiment 3 of the present invention.
Fig. 5 is an explanatory diagram of an operation of the motor drive system according to embodiment 3 of the present invention.
Fig. 6 is a schematic configuration diagram showing a motor drive system according to embodiment 4 of the present invention.
Fig. 7 is an explanatory diagram of an operation of the motor drive system according to embodiment 4 of the present invention.
Detailed Description
Embodiment 1.
Fig. 1 is a schematic configuration diagram showing a motor drive system according to embodiment 1 of the present invention, and in fig. 1, the motor drive system 1 includes a motor drive device 100, a host controller 200, a drive unit 300, and a detector 400.
The driving unit 300 includes a motor 301 and a driving mechanism 302, and the motor 301 and the driving mechanism 302 are mechanically connected to each other and driven by the motor 301. The drive mechanism 302 is, for example, a machining table that is driven to rotate a ball screw inside a machine tool and moves the table in a linear direction. The motor 301 is, for example, a servo motor, and a ball screw is mechanically connected to and driven by a rotation output shaft of the motor 301 through a coupling. In fig. 1, the motor 301 and the drive mechanism 302 are connected by a double line, which indicates a mechanical connection.
The detector 400 is provided in the motor 301, for example, and detects a driving position of the motor 301, and outputs the detected position to the motor driving device 100 as a driving detection value Xb.
The motor drive device 100 includes a drive control unit 101, a drive command acquisition unit 102, a drive detection value acquisition unit 103, a current detection unit 104, a characteristic estimation unit 111, and a characteristic estimation instruction acquisition unit 112. The drive detection value acquisition unit 103 acquires the position of the motor 301 from the detector 400 as a drive detection value Xb. The drive command acquisition unit 102 acquires a target value for the position of the motor 301 from the host controller 200 as a drive command signal Xr. The drive control unit 101 performs a control operation based on the drive command signal Xr and the drive detection value Xb, applies a voltage to the motor 301 to flow a current Im, thereby generating a drive torque in the motor 301, and drives the motor 301 so that the drive detection value Xb follows the drive command signal Xr. The current detection unit 104 detects a current Im flowing through the motor 301 in the motor drive device 100, and transmits the current Im to the drive control unit 101 as a current detection value Ib. The drive control unit 101 outputs, as the control state value D1, information such as a calculated value in the middle of a control operation for calculating a value of voltage output for the motor 301 to flow the current Im based on the drive command signal Xr, the motion detection value Xb, and the current detection value Ib, an electrical or mechanical constant of the motor 301 and a mechanical constant of the drive mechanism 302, which are necessary for estimating the characteristics of the drive unit 300, to the characteristic estimation unit 111. The control state value D1 includes, for example, a detected value of the speed of the motor 301, a detected value of a current of a component for generating torque in the motor 301, a torque constant converted from the detected value of the current into a torque output value of the motor 301, a load moment constant obtained by adding a moment of inertia value of a rotor of the motor 301 and a moment of inertia value of a portion of the drive mechanism 302 driven by the motor 301, and the like.
The characteristic estimation instruction acquisition unit 112 acquires the characteristic estimation instruction signal C1 from the host controller 200 outside the motor drive device 100. The characteristic estimating unit 111 acquires the control state value D1 from the drive control unit 101, and outputs a characteristic estimated value E1 in accordance with the characteristic estimation instruction signal C1 acquired from the external host controller 200.
Here, the characteristic estimation instruction signal C1 is a signal for instructing whether or not to estimate the characteristic value of the motor 301 or the drive mechanism 302 based on the driving condition of the driving operation determined by the driving command signal Xr, and when the characteristic estimation instruction signal C1 is an instruction to estimate, the characteristic estimation unit 111 estimates the state of the driving unit 300 based on the control state value D1 acquired from the drive control unit 101, and outputs the estimated value as the characteristic estimation value E1. For example, as the characteristic estimated value E1, a total value of the friction torque of the motor 301 and the friction force of the driving mechanism 302 is estimated as a component of the friction output from the torque of the motor 301, and a friction estimated value is output. The friction is explained, for example, by an example in which kinetic friction, which is coulomb friction whose magnitude changes due to a normal force generated by a load, is dominant, and viscous friction added due to a velocity is small and negligible.
The characteristic estimating unit 111 estimates friction as the characteristic estimated value E1, for example, as described below. The characteristic estimating unit 111 receives, as the control state value D1, a detected value of speed, a detected value of current, a torque constant converted from current to torque, and a load moment of inertia constant, for example, from the drive control unit 101. Then, the detected value of the current is multiplied by a torque constant, and the generated load torque is calculated. Further, an acceleration torque that generates an acceleration is calculated by multiplying an acceleration obtained by time-differentiating a detected value of the velocity by a load moment of inertia constant. If the acceleration torque is subtracted from the calculated load torque, the torque required for the driving operation is calculated in addition to the acceleration, and if it is considered that there is no disturbance torque, the calculated torque is used as the instantaneous estimated value of the friction. The instantaneous estimated value of friction is an estimated value of friction, which is averaged by a filter having a predetermined time constant, such as a first-order lag system.
When the characteristic estimation instruction signal C1 instructs not to estimate the characteristic, the characteristic estimation unit 111 does not estimate the characteristic estimation value E1. In the estimation of the characteristic value, when there is a stored variable which is stored in operation as an integral variable of a filter of the first-order lag system, the stored variable is not updated but stored and the estimation is interrupted while the characteristic estimation instruction signal C1 indicates that the estimation is not to be performed, and when the characteristic estimation instruction signal C1 indicates that the estimation is to be performed again, the update of the stored variable is restarted and the estimation is performed. As another method, while the characteristic estimation instruction signal C1 indicates that no estimation is to be performed, the estimation may be stopped, the stored variable may not be updated or may be set to a predetermined value, and when the characteristic estimation instruction signal C1 indicates that estimation is to be performed again, the stored variable may be set to a predetermined value such as an initial value, and the stored variable may be updated from this time on to perform estimation. The characteristic estimated value E1 output when no estimation is performed is stored and output as the characteristic estimated value E1 immediately before the instruction to change the characteristic estimation instruction signal C1 to no estimation is performed, for example. As the characteristic estimated value E1 to be output when no estimation is performed, a predetermined value may be output so that a device or an operator outside the motor drive device 100 can recognize that the estimation of the characteristic estimated value E1 is not performed.
Here, the upper controller 200 generates a drive command signal Xr that is a target value of a detection value Xb obtained based on the position or speed of the motor 301, and transmits the drive command signal Xr to the motor drive device 100.
In an operation, for example, in a machine tool or the like as a production facility having the drive unit 300, it is necessary to sequentially drive the plurality of motors 301 attached to the machine tool at an appropriate timing (timing) and simultaneously drive the plurality of motors 301 in synchronization, and to drive the motors 301 based on sensor input states from a plurality of sensor devices (not shown in fig. 1) such as a light shielding sensor that detects whether or not a workpiece is input.
Therefore, in the operation, unlike a test operation when the motor drive device 100 and the drive unit 300 are adjusted in a production facility or the like, the motor drive device 100 is connected to the host controller 200, the host controller 200 generates a drive command signal Xr that becomes a target value of a detection value based on the position or speed of the motor 301 according to an operation schedule, and transmits the drive command signal Xr to the motor drive device 100, and the motor drive device 100 acquires the drive command signal Xr from the host controller 200 outside the motor drive device 100 and drives the motor 301. In addition, since the operating conditions are known by the operating program or the like as the operation schedule in the upper-level controller 200, the characteristic estimation instruction signal C1 can be generated based on the operating conditions in many cases.
The characteristic estimation instruction signal C1 may be acquired by serial communication or may be input via a parallel digital signal in the motor drive device 100. When the drive command signal Xr from the host controller 200 or the like is acquired by the motor drive device 100 through communication, if the characteristic estimation instruction signal C1 is acquired through the same communication path as the communication path through which the drive command signal Xr is received, the number of communication circuits and communication wiring is small, and synchronization between the drive command signal Xr and the characteristic estimation instruction signal C1 can be easily acquired. When the characteristic estimation instruction signal C1 is acquired via parallel digital signal input, the characteristic estimation instruction signal C1 can be acquired from a plurality of types of host controllers 200 and the like without being restricted by a communication protocol and the like.
Fig. 2 is a diagram illustrating the operation of the motor drive system 1, and shows an example of a time series of a state in which friction of a ball screw of a machining table is estimated as a characteristic estimated value E1 in an example of an operation of the machining table that is moved by the ball screw while carrying a workpiece as a drive mechanism 302 driven by a motor 301. For comparison, the case where the characteristic estimation instruction signal C1 is not provided and the friction is always estimated is represented by the constant friction estimation value in fig. 2. The working operation is an operation performed when the drive unit performs a normal operation, and for example, an operation performed when a machine tool as a production facility having the drive unit performs a normal production operation. In fig. 2, the operation is performed for the workpiece W1 in the period 511, the type of workpiece is changed to the workpiece W2 having a load lighter than the workpiece W1 in the period 512, and the operation is performed for the workpiece W1 in the periods 513, 514, and 515 with the type of workpiece changed again. There are 2 types of operation modes, the operation mode P1 is performed in the periods 511, 512, and 513, the operation mode P2 is changed to the period 514, and the operation mode P1 is again returned to the period 515 to perform the operation. P2 is an operation mode in which the interval time from the machining of a certain workpiece to the machining of the next workpiece is longer than that in operation mode P1, for example.
In period 512, since the workpiece type is changed to W2 and the load is reduced, the friction at the ball screw that moves the table on which the workpiece is placed is reduced, and the friction estimated value always fluctuates to a value smaller than period 511.
In the period 514, the interval time between the machining of the workpiece and the machining is longer, and the amount of heat radiation from the ball screw during the interval time is increased, so that the temperature of the ball screw is lower than that in the period 513, the temperature is lowered, the friction is increased, and the friction estimated value is always larger than that in the period 513.
For example, when the friction value is displayed and outputted as an index of the secular change of the motor 301 and the driving mechanism 302 during the operation, if the estimated friction value greatly fluctuates and the display output value fluctuates due to the change of the operation conditions such as the change of the kind of the workpiece and the change of the operation mode as described above, it is difficult for the operator who monitors the driving mechanism 302 to grasp the characteristics of the driving mechanism 302.
Therefore, for example, as a reference for observing the secular change due to the friction, the operator determines the characteristic estimated value E1 and estimates the friction during the working operation of the workpiece W1. The method of determining the workpiece to be used as the reference may be, for example, a heavy workpiece whose S/N ratio to noise is good in friction estimation because the friction force has a large value, or a workpiece whose machining opportunity is high in production and in operation because of mass production. In addition, regarding the operation mode, it is possible to determine the characteristic estimation value E1 in the operation of the operation mode P1 based on the fact that the operation mode is an operation mode which is used in a large amount in production and has many opportunities to perform operation.
Therefore, in the upper controller 200, the estimation of the characteristic estimation value E1 is registered in advance as an estimation determination criterion for generating the characteristic estimation instruction signal C1 and stored in the upper controller so as to be estimated when the type of the workpiece is W1 and the operation mode is P1. The upper controller determines the type and operation mode of the workpiece based on the production plan, and performs the operation as the operation condition for performing the machining during the operation. Based on the operating conditions such as the determined type and operation mode of the workpiece and the stored estimation determination criterion, it is determined whether or not the characteristic estimation value E1 is estimated under the operating conditions of the operation, and a characteristic estimation instruction signal C1 is generated as an instruction to perform estimation or an instruction not to perform estimation and is output to the motor drive device 100. The characteristic estimation instruction signal C1 in fig. 2 indicates "estimation" when an instruction to estimate is given, and indicates "interruption" when an instruction to estimate is not given.
In the motor drive device 100, a drive command signal Xr is received, a current is caused to flow through the motor 301 so that a drive detection value Xb follows the drive command signal Xr, and a drive torque is output to drive the drive mechanism 302. Meanwhile, based on the acquired characteristic estimation instruction signal C1, if the characteristic estimation instruction signal C1 is an instruction to perform estimation, the characteristic estimation unit 111 performs an estimation operation. When the characteristic estimation instruction signal C1 is changed from the instruction to perform estimation to the instruction to not perform estimation, the value of the characteristic estimation value E1 immediately before the change is stored, and the stored value is output while the characteristic estimation instruction signal C1 is the instruction to not perform estimation.
Thus, even if the type of the workpiece is changed, the operation mode is changed, and the operation condition is changed, the characteristic estimated value E1 of friction or the like can be output as shown in the lower part of fig. 2, and the estimated value of the characteristic can be used without being affected by the change of the operation condition.
Therefore, when the characteristic estimated value E1 is displayed and output as an index of the secular change of the motor 301 and the driving mechanism 302 during the operation, the operator who monitors the driving mechanism 302 can easily grasp the secular change of the characteristic of the driving mechanism 302. In addition, even when the setting of the drive control such as the friction compensation is changed in accordance with the change in the characteristics such as the friction due to the secular change of the motor 301 and the drive mechanism 302 during the operation, the secular change can be grasped and set without being affected by the variation of the characteristic estimated value E1 due to the operation conditions.
That is, the motor drive device 100 according to the present embodiment includes: a drive detection value acquisition unit 103 that acquires a drive detection value Xb obtained based on the position of the motor 301 that drives the drive mechanism 302 by the motor 301; a drive command acquisition unit 102 that acquires a drive command signal Xr that is a target value of the drive detection value Xb; a drive control unit 101 that performs a control operation so that the drive detection value Xb follows the drive command signal Xr, and causes a current to flow to the motor 301 to drive the motor 301; a characteristic estimation instruction acquisition unit 112 that acquires, from the outside, a characteristic estimation instruction signal C1 that instructs whether or not to estimate the characteristic value of the motor 301 or the drive mechanism 302, based on the operating condition of the driving operation determined by the drive command signal Xr; and a characteristic estimating unit that estimates a characteristic value based on the control state value D1 used in the control calculation of the drive control unit 101 when the characteristic estimation instruction signal C1 is an instruction to perform estimation, outputs a characteristic estimation value E1, and does not estimate when the characteristic estimation instruction signal C1 is an instruction to perform no estimation, thereby enabling output of an estimation value of a characteristic without being affected by changes in the operating conditions such as changes in the operating mode and changes in the type of the workpiece.
Further, in the motor drive system 1, since the motor drive device 100 and the upper controller 200 that outputs the drive command signal Xr and the characteristic estimation instruction signal C1 to the motor drive device 100 are provided, the estimated value of the characteristic can be used without being affected by the change in the operating conditions.
Embodiment 2.
The configuration of a motor drive device and a motor drive system according to embodiment 2 of the present invention will be described with reference to fig. 1 and 3. In embodiment 1, an example is shown in which a servo motor is used as the motor 301 and a machining table is used as the drive mechanism 302, but in embodiment 2, the motor 301 is an induction motor of a spindle that rotates a machining tool of a machine tool, and the drive mechanism 302 is a machining tool of the machine tool.
The detector 400 detects the speed of the motor 301 and outputs the detected speed as a drive value Xb, the drive control unit 101 controls the speed of the motor 301, the characteristic estimation unit 111 estimates the vibration amplitude of the speed deviation obtained by subtracting the drive detection value Xb from the drive command signal Xr as a characteristic estimation value E1, and the characteristic estimation command signal C1 is instructed as to whether or not the operation is disturbed. The estimated value of the vibration amplitude, which is the speed deviation of the characteristic estimated value E1, is not an observation of disturbance torque applied to the rotor of the motor 301 during cutting, but is a determination of whether or not the rotor of the motor 301 is rotating smoothly by the vibration amplitude when the rotor of the motor 301 is rotating but not cutting, and monitors the change over time of a bearing or the like that supports the rotor of the motor 301.
More specifically, the drive mechanism 302 is a machining tool such as an end mill that performs cutting inside the machine tool. The motor 301 is, for example, an induction motor, and a machining tool is mechanically attached to a rotation output shaft of a rotor of the motor 301 as a driving mechanism 302 via a tool chuck to be driven.
The detector 400 is disposed, for example, so as to be able to detect the speed of the motor 301 being driven, and output the detected speed as a drive detection value Xb to the motor drive device 100.
The drive detection value acquisition unit 103 acquires the speed of the motor 301 from the detector 400 as a drive detection value Xb. The drive command acquisition unit 102 acquires a target value for the speed of the motor 301 from the host controller 200 as a drive command signal Xr. The drive control unit 101 performs a control operation based on the drive command signal Xr and the drive detection value Xb, applies a voltage to the motor 301, and causes the motor 301 to generate a drive torque by flowing a current Im, thereby driving the motor 301 so that the drive detection value Xb follows the drive command signal Xr. The drive control unit 101 outputs the control state value D1 to the characteristic estimating unit 111. The control state value D1 includes, for example, a speed deviation calculated by the drive control unit 101 for control calculation, which is obtained by subtracting a drive detection value Xb, which is a speed detection value of the motor 301, from a drive command signal Xr, which is a target value for the speed of the motor 301. For example, the motor 301 is controlled so as to follow a target value of a speed having a constant value, and if there is no problem with a bearing or the like, the speed deviation is smooth. Here, for example, if a ball in a bearing supporting the rotor of the motor 301 is damaged, a periodic external force is generated with respect to the rotation of the motor 301, and vibration of speed deviation occurs. However, during the cutting process, the speed deviation causes vibration due to a periodic disturbance torque when the machining tool cuts the workpiece.
The characteristic estimating unit 111 acquires the control state value D1 from the drive control unit 101, and outputs a characteristic estimated value E1 in accordance with the characteristic estimation instruction signal C1 acquired from the host controller 200. The characteristic estimation instruction signal C1 is a signal instructing whether or not to perform an estimation operation, and when the characteristic estimation instruction signal C1 is an instruction to perform an estimation operation, the characteristic estimation unit 111 estimates the characteristic of the drive unit 300 based on the control state value D1 acquired from the drive control unit 101, and outputs the estimated value as the characteristic estimation value E1. When the characteristic estimation instruction signal C1 instructs not to estimate the characteristic, the characteristic estimation unit 111 does not estimate the characteristic estimation value E1. As a method of estimating the characteristic estimation value E1 from the control state value D1, for example, a speed deviation acquired as the control state value D1 is subjected to a high-pass filter to remove low-frequency components such as offset (offset) and extract vibration components, the absolute values of the vibration components are averaged to obtain a vibration amplitude estimation value for estimating the amplitude of vibration, and the vibration amplitude estimation value is output as the characteristic estimation value E1.
Fig. 3 is an example of a time-series situation in which, during an operation in which the machining tool as the drive mechanism 302 is driven by the motor 301, a vibration amplitude estimation value that is a speed deviation of the motor 301 that rotates the machining tool is estimated as the characteristic estimation value E1. For comparison, the case where the vibration amplitude of the velocity deviation is estimated at all times is represented by the constant vibration amplitude estimation value in fig. 3. In the periods 521, 523, and 525 in fig. 3, the movement command of the table on which the workpiece is placed is the positioning command G00. The periods 522, 524 are cutting movement commands G01. In the periods 522 and 524, the influence of vibration due to disturbance of the cutting external force when the machining tool cuts the workpiece occurs during the operation, and therefore the vibration amplitude of the speed deviation becomes large.
In the motor 301 and the driving mechanism 302 during the working operation, for example, if the constant vibration amplitude estimation value of the speed deviation is displayed and outputted as an index of the temporal change of the bearing that supports and rotates the rotor of the motor 301 to which the machining tool is attached, the display output value of the constant vibration amplitude estimation value greatly fluctuates due to the change of the operation conditions such as the execution of the operation in which the disturbance of the cutting process occurs as described above. If an operator monitoring the driving mechanism 302 refers to a constant vibration amplitude estimation value including a speed deviation of the fluctuation in order to grasp characteristics appearing due to a secular change of the driving mechanism 302, it is difficult to grasp the characteristics of the driving mechanism 302 because of the influence of the operation conditions including the execution of the operation in which the disturbance occurs.
Therefore, the characteristic estimated value E1 is output as described below. Since the upper controller 200 stores the operation program, it can be seen from the description of the movement command in the operation program whether the movement command to be operated next is cutting movement accompanied by cutting or positioning movement without cutting. Therefore, for example, in the host controller 200, when the command for moving the machining table in the operation program is the positioning movement G00, the characteristic estimation instruction signal C1 is an instruction to perform estimation, and when the command is the cutting movement G01 in which the disturbance due to the external cutting force is present, the characteristic estimation instruction signal C1 is an instruction not to perform estimation. In this way, the determined characteristic estimation instruction signal C1 is output from the host controller 200 to the motor drive device 100. The characteristic estimation instruction signal C1 in fig. 3 indicates "estimation" when an instruction to estimate is given, and indicates "interruption" when an instruction to estimate is not given.
In the motor drive device 100, a drive command signal Xr is received, a current is caused to flow through the motor 301 so that a drive detection value Xb follows the drive command signal Xr, and a drive torque is output to drive the drive mechanism 302. In parallel, based on the acquired characteristic estimation instruction signal C1, if the characteristic estimation instruction signal C1 is an instruction to perform estimation, the characteristic estimation unit 111 performs estimation. If the characteristic estimation instruction signal C1 is changed from the instruction to perform estimation to the instruction to not perform estimation, for example, the value of the characteristic estimation value E1 immediately before the change is stored, and the stored value is output during the period in which the characteristic estimation instruction signal C1 is an instruction to not perform estimation.
Accordingly, even when the operating conditions are changed such as the implementation of the operation in which the disturbance is present, the estimated value of the characteristic can be used without being affected by the operating conditions, because the estimated value E1 of the characteristic does not greatly vary when the operation in which the disturbance is present is implemented, and is output as indicated by the estimated value E1 of fig. 3. Thus, when the characteristic estimated value E1 is displayed and output as an index of the secular change of the motor 301 or the driving mechanism 302 during the operation, the operator who monitors the driving mechanism 302 can easily grasp the secular change of the characteristic of the driving mechanism 302. In addition, when the setting of the vibration suppression function is changed in accordance with the change in the vibration amplitude of the motor 301 and the driving mechanism 302 due to the secular change during the operation, the secular change can be grasped and set without being affected by the change in the characteristic estimation value E1.
Therefore, in the motor drive device 100 and the motor drive system 1 according to the present embodiment, similarly to embodiment 1, the estimated value of the characteristic can be output without being affected by a change in the operation conditions such as execution of the operation in which there is disturbance, and the estimated value can be used.
Embodiment 3.
A motor drive device and a motor drive system according to embodiment 3 of the present invention will be described. Fig. 4 is a schematic configuration diagram showing a motor drive system according to embodiment 3 of the present invention. In fig. 4, the same or corresponding components are denoted by the same reference numerals as in fig. 1, and the description thereof will be omitted. The difference from embodiment 1 is that the motor drive device 100 includes the abnormality diagnosis instruction acquisition unit 122 and the abnormality diagnosis unit 121, does not include the characteristic estimation instruction acquisition unit 112, and the characteristic estimation unit 111 outputs the constant characteristic estimation value E0.
The characteristic estimating unit 111 acquires the control state value D1 from the drive control unit 101, estimates the characteristic value of the drive unit 300 based on the control state value D1, and outputs the value estimated regardless of the operating conditions as the constant characteristic estimated value E0.
The abnormality diagnosis instruction acquisition unit 122 acquires an abnormality diagnosis instruction signal C2 from the host controller 200 outside the motor drive device 100.
The abnormality diagnosis unit 121 acquires the constant characteristic estimation value E0 from the characteristic estimation unit 111, performs abnormality diagnosis in accordance with the abnormality diagnosis instruction signal C2 acquired from the external host controller 200, and outputs an abnormality determination signal F1 as a result of the abnormality diagnosis. When the abnormality diagnosis instruction signal C2 is an instruction to perform diagnosis, the abnormality diagnosis unit 121 performs abnormality diagnosis of the drive unit 300 based on the constant characteristic estimation value E0 obtained from the characteristic estimation unit 111. As the determination process of the abnormality diagnosis, for example, it is determined whether or not the constant characteristic estimated value E0 falls within an allowable range of a preset constant characteristic estimated value E0. As the allowable range, in the initial stage of starting the drive mechanism 302, for example, an allowable range upper limit and an allowable range lower limit that are set to a certain allowable range width with respect to the average steady characteristic estimated value E0 are set. If the abnormality diagnosis instruction signal C2 is an instruction to perform diagnosis, the abnormality diagnosis unit 121 performs abnormality diagnosis, determines that the constant characteristic estimation value E0 is abnormal when it exceeds the allowable range, and outputs an abnormality determination signal F1 as an abnormality. When the constant characteristic estimated value E0 falls within the allowable range, it is determined that the state is not abnormal, and an abnormality determination signal F1 is output as normal. If the abnormality diagnosis instruction signal C2 indicates that diagnosis is not to be performed, the abnormality diagnosis unit 121 does not perform abnormality diagnosis based on the constant characteristic estimation value E0, and outputs the abnormality determination signal F1 as normal. The abnormality determination signal F1 is output to, for example, a display provided in the motor drive device 100, and the display displays the detected abnormality as a warning, and an operator monitoring the motor drive device 100 can recognize that the constant characteristic estimated value E0 is determined to be in an abnormal state by observing the display.
Fig. 5 shows an example of a time series of a state in which the friction of the ball screw of the machining table is estimated as the constant characteristic estimated value E0 and abnormality diagnosis is performed based on the estimated constant characteristic estimated value E0 in an example of the operation of the machining table that is moved by the ball screw while carrying a workpiece as the drive mechanism 302 driven by the motor 301. In fig. 5, the constant characteristic estimated value E0 is represented by a constant friction estimated value obtained by estimating friction at all times. For example, in period 531, the operation is performed with respect to workpiece W1, in period 532, the type of workpiece is changed, and the operation is performed with workpiece W2 having a load lighter than that of workpiece W1, and in periods 533, 534, 535, the operation is performed with respect to workpiece W1 with the type of workpiece changed again. The operation mode is changed from the operation mode P1 in the periods 531, 532, 533 to the operation mode P2 in which the interval time from the machining of a certain workpiece to the machining of the next workpiece is longer than the operation mode P1 in the period 534, and the operation is performed. In period 535, the operation mode returns to operation mode P1 again to perform the operation.
In the period 532, the type of the workpiece is changed to W2, and the load is reduced, so that the friction at the ball screw on which the workpiece is placed is reduced, and the constant friction estimated value as the constant characteristic estimated value E0 is changed to a value smaller than the period 531 and smaller than the lower limit of the allowable range.
In the period 534, since the interval time between the machining of the workpiece and the machining is long and the heat radiation amount of the ball screw in the interval time is large, the temperature of the ball screw is lower than that in the period 533, and the friction is large due to the temperature decrease, and the constant friction estimated value as the constant characteristic estimated value E0 is a value larger than the period 533 and larger than the upper limit of the allowable range.
From period 533 to period 535, the friction gradually increases due to aging regardless of the operating conditions, and at a time in the middle of period 535, the constant friction estimated value as the constant characteristic estimated value E0 exceeds the upper limit of the allowable range.
For example, when the abnormality diagnosis is always performed based on the constant friction estimated value as the constant characteristic estimated value E0, the allowable range is shifted in the period 532 or the period 534 in which the constant friction estimated value greatly varies due to a change in the operation conditions such as a change in the type of the workpiece or a change in the operation mode, and the abnormality is erroneously detected in the abnormality diagnosis.
Therefore, for example, as a reference for performing the abnormality diagnosis due to the secular change of friction, the abnormality diagnosis is performed in the operating operation of the operation pattern P1 with respect to the type W1 of the workpiece.
For example, as a reference for performing the abnormality diagnosis, the fact that the abnormality diagnosis is performed when the type of the workpiece is W1 and the operation mode is P1 is registered in advance and stored in the host controller 200. The upper controller 200 performs the operation by outputting the drive command signal Xr to the motor drive device 100 in accordance with the type and operation mode of the workpiece determined as the operation condition for performing the operation based on the production plan. The upper controller 200 generates the abnormality diagnosis instruction signal C2 as an instruction to perform diagnosis or an instruction not to perform diagnosis, based on the operation conditions such as the type and operation mode of the work to be operated and the operation conditions stored in advance, and outputs the generated instruction to the motor drive device 100. The abnormality diagnosis instruction signal C2 in fig. 5 indicates "diagnosis" when an instruction to perform diagnosis is given, and indicates "interrupt" when an instruction to not perform diagnosis is given.
In the motor drive device 100, a drive command signal Xr is received, a current is caused to flow through the motor 301 so that a drive detection value Xb follows the drive command signal Xr, and a drive torque is output to drive the drive mechanism 302. The characteristic estimating unit 111 acquires the control state value D1 from the drive control unit 101, estimates the characteristic of the drive unit 300 based on the control state value D1, and outputs the value estimated regardless of the operating conditions as the constant characteristic estimated value E0. The abnormality diagnosis instruction acquisition unit 122 acquires the abnormality diagnosis instruction signal C2 from the external host controller 200.
The abnormality diagnosis unit 121 acquires the abnormality diagnosis instruction signal C2 from the abnormality diagnosis instruction acquisition unit 122, acquires the constant characteristic estimation value E0 from the characteristic estimation unit 111 when the abnormality diagnosis instruction signal C2 is an instruction to perform diagnosis, performs abnormality diagnosis based on the constant characteristic estimation value E0, and outputs the abnormality determination signal F1 as an abnormality determination result when an abnormality is detected. When no abnormality is detected, the abnormality determination signal F1 is output as a result of the normality determination. When the abnormality diagnosis instruction signal C2 indicates that diagnosis is not to be performed, abnormality diagnosis is suspended and the abnormality determination signal F1 is output as a result of normal determination. The abnormality determination signal F1 in fig. 5 indicates "abnormal" in the case of the abnormality diagnosis result and indicates "normal" in the case of the normal determination result.
In the period 531 in fig. 5, since the type of the workpiece is W1 and the operation mode is P1, the abnormality diagnosis instruction signal C2 is used as an instruction to perform diagnosis, and the abnormality diagnosis instruction signal C2 is used as an instruction to perform diagnosis, and therefore the abnormality diagnosis is performed by the abnormality diagnosis unit 121, but since the estimated constant friction value as the estimated constant characteristic value E0 falls within the allowable range, the abnormality determination signal F1 is output as a result of normal determination.
In the period 532, the type of the workpiece is changed to W2, and the constant friction estimated value as the constant characteristic estimated value E0 is a value smaller than the lower limit of the allowable range, but since the type of the workpiece is W2, the abnormality diagnosis instruction signal C2 indicates that no diagnosis is performed, and since the abnormality diagnosis instruction signal C2 indicates that no diagnosis is performed, the abnormality diagnosis unit 121 does not perform the abnormality diagnosis, and the abnormality determination signal F1 is output as the result of the normal determination.
The period 533 is the same operation as the period 531, and the abnormality determination signal F1 is output as a result of the normality determination.
In the period 534, the operation mode is changed to P2, and the constant friction estimated value as the constant characteristic estimated value E0 is a value larger than the upper limit of the allowable range, but since the operation mode is P2, the abnormality diagnosis instruction signal C2 is an instruction to not perform diagnosis, and since the abnormality diagnosis instruction signal C2 is an instruction to not perform diagnosis, the abnormality diagnosis unit 121 does not perform abnormality diagnosis, and the abnormality determination signal F1 is output as the result of the normal determination.
In the period 535, since the type of the workpiece is W1 and the operation mode is P1, the abnormality diagnosis instruction signal C2 is used as an instruction to perform diagnosis, and since the abnormality diagnosis instruction signal C2 is an instruction to perform diagnosis, the abnormality diagnosis unit 121 performs abnormality diagnosis, and if the constant friction estimated value as the constant characteristic estimated value E0 increases due to aging and becomes larger than the allowable range upper limit in the period 535, an abnormality is detected, and the abnormality determination signal F1 outputs an abnormality determination result.
As described above, even when the operating condition is changed such as a change in the type of the workpiece or a change in the operating mode, and the constant characteristic estimation value E0 such as friction is output as a result of the change in the operating condition, the abnormality diagnosis instruction signal C2 that instructs whether or not to perform abnormality diagnosis in accordance with the operating condition is obtained from the outside, and when the abnormality diagnosis instruction signal C2 is an instruction to perform diagnosis, the characteristic estimation value E1 is obtained from the characteristic estimation unit 111, abnormality diagnosis is performed, and the abnormality determination signal F1 is output, and when the abnormality diagnosis instruction signal F1 is an instruction to perform no diagnosis, abnormality diagnosis can be performed based on the characteristic estimation value that is not affected by the change in the operating condition. Therefore, erroneous detection of the abnormality diagnosis can be reduced, and the abnormality diagnosis with high reliability can be performed.
That is, the motor drive device 100 and the motor drive system 1 according to the present embodiment include: a drive detection value acquisition unit 103 that acquires a drive detection value Xb based on the position of the motor 301 that drives the drive mechanism 302 by the motor 301; a drive command acquisition unit 102 that acquires a drive command signal Xr that is a target value of the drive detection value Xb; a drive control unit 101 that performs a control operation so that the drive detection value Xb follows the drive command signal Xr, and causes the motor 301 to perform a driving operation by causing a current Im to flow to the motor 301; a characteristic estimating unit 111 that acquires a control state value D1 used for control calculation from the drive control unit 101, estimates a characteristic value of the motor 301 or the drive mechanism 302, and outputs a characteristic estimated value E0; an abnormality diagnosis instruction acquisition unit 122 that acquires, from the outside, an abnormality diagnosis instruction signal C2 that instructs whether or not to perform an abnormality diagnosis based on the characteristic estimation value E0, based on the operating condition of the driving operation determined by the drive command signal Xr; and an abnormality diagnosis unit 121 that performs abnormality diagnosis based on the characteristic estimation value E0 of the characteristic estimation unit 111 and outputs an abnormality determination signal F1 when the abnormality diagnosis instruction signal C2 indicates an instruction to perform diagnosis, and does not perform abnormality diagnosis when the abnormality diagnosis instruction signal C2 indicates an instruction not to perform diagnosis, so that it is possible to perform abnormality diagnosis based on characteristic estimation without being affected by changes in the operating conditions such as changes in the operating mode and changes in the type of workpiece.
Further, since the abnormality diagnosing unit 121 that estimates the constant characteristic estimated value E0 regardless of the operating conditions and acquires the constant characteristic estimated value E0 is not affected by the change in the operating conditions, the constant characteristic estimated value E0 can be referred to and used even in other functional applications that want to refer to and use the constant characteristic estimated value E0 including the fluctuation due to the changed operating conditions. In addition, when there are a plurality of abnormality diagnosing units 121 that perform abnormality diagnosis under different operating conditions, since each abnormality diagnosing unit 121 can refer to and acquire 1 constant characteristic estimation value E0 to perform abnormality diagnosis, it is possible to share the processing of the characteristic estimating unit 111, and it is possible to realize with a small processing load and to reduce the number of steps for developing the processing.
The abnormality determination signal F1 has been described as two values, i.e., an abnormality determination result indicating that an abnormality is detected and a normal determination result indicating that no abnormality is detected, but may be a signal indicating the remaining life obtained by estimating the remaining time until the drive unit 300 becomes unable to drive due to aging. Even when such a signal is used, the estimated value of the characteristic can be used without being affected by changes in the operating conditions such as changes in the type of workpiece and changes in the operating mode, and highly reliable abnormality diagnosis can be performed. Further, by outputting a signal indicating the remaining life on a display not shown and referring to the signal by an operator monitoring the driving unit 300, the operator can predict a highly reliable maintenance timing.
Embodiment 4.
Fig. 6 is a schematic configuration diagram showing a motor drive system according to embodiment 4 of the present invention. In fig. 6, the same or corresponding components are denoted by the same reference numerals as in fig. 1, and the description thereof will be omitted. The difference from embodiment 1 of the present invention is that the motor drive device 100 includes an abnormality diagnosis unit 121, an abnormality reference creation unit 131, and an abnormality reference creation instruction acquisition unit 132, and the abnormality reference creation instruction acquisition unit 132 acquires an abnormality reference creation instruction signal C3 from a host controller external to the motor drive device 100.
The abnormality diagnosing unit 121 obtains the characteristic estimation value E1 from the characteristic estimating unit 111, performs abnormality diagnosis, and outputs an abnormality determination signal F1 as a result of the abnormality diagnosis.
The abnormality reference creation instruction acquisition unit 132 acquires the abnormality reference creation instruction signal C3 from the host controller 200 outside the motor drive device 100.
The abnormality reference creating unit 131 acquires the characteristic estimation value E1 from the characteristic estimating unit 111, determines whether or not to use the characteristic estimation value E1 for the abnormality reference creating process based on the abnormality reference creating instruction signal C3 acquired from the external host controller 200, and creates the abnormality diagnostic reference H1. The created abnormality diagnosis reference H1 is output to the abnormality diagnosis unit 121.
The processing for creating the abnormality diagnosis reference H1 by the abnormality reference creation unit 131 is performed, for example, as follows. The abnormality diagnosis criterion H1 is previously determined to be created based on the characteristic estimated value E1 of how long the period is, and is set as a criterion creation period. The abnormal reference creating unit 131 acquires and stores the characteristic estimation value E1 in the reference creating period, and calculates the average value and the standard deviation from the stored characteristic estimation value E1. Then, the abnormality diagnosis unit 121 determines a specification of the occurrence probability of the detection of an abnormality as the occurrence probability in advance, and calculates a reference coefficient by a normal distribution based on the occurrence probability. Based on the calculated average value, standard deviation, and reference coefficient of the characteristic estimation value E1, the upper limit and lower limit of the allowable range are created as the abnormality diagnosis reference H1 by, for example, the average value ± standard deviation × reference coefficient. When the characteristic estimate value E1 during the reference creation period is acquired and stored in order to calculate the average value and the standard deviation, the characteristic estimate value E1 is stored when the abnormal reference creation instruction signal C3 acquired from the external host controller 200 is an instruction for creation, and is not stored when the abnormal reference creation instruction signal C3 is an instruction not for creation. The storage of the characteristic estimation value E1 is performed until the abnormal reference creation instruction signal C3 is an instruction for creation and the total of the stored times or times becomes a reference creation period. The storage of the characteristic estimate value E1 is stored in a nonvolatile memory such as an eeprom (electrically Erasable Programmable Read Only memory) or a flash memory that can be used by the abnormality reference creation unit 131, so that the characteristic estimate value E1 in the reference creation period of days that spans the time when the power supply of the motor drive apparatus 100 is cut can be used to create the abnormality diagnosis reference H1 in an operation in which the operation for 1 day is ended to cut off the power supply of the motor drive apparatus 100 and the operation is resumed by turning on the power supply of the motor drive apparatus 100 the next day.
With respect to the operation, an example of creating the abnormality diagnosis criterion H1 in the motor drive device 100 will be described with reference to fig. 7, and the motor drive device 100 is configured to estimate, for example, friction of a ball screw of a machining table of a machine tool, which is the drive mechanism 302, as the characteristic estimation value E1, and determine that an abnormality occurs if the change is large, in addition to the secular change, with respect to the change in friction caused by the change in the type of the workpiece.
In fig. 7, the operation is performed for the workpieces W3, W4, and W5 in the periods 543, 548, and 552, respectively, and the operation is performed for the workpiece W1 in the other periods. In the operation mode, the operation mode P2 is operated during the periods 545 and 550, and the operation mode P1 is operated in addition to the operation mode. The characteristic estimation instruction signal C1 is an instruction to perform estimation when the operation mode is P1 and an instruction to not perform estimation when P2, without changing the type of the workpiece. The characteristic estimation instruction signal C1 of fig. 7 indicates "estimation" when an instruction to estimate is given, and indicates "interruption" when an instruction to estimate is not given. Based on the characteristic estimation instruction signal C1, the characteristic estimation unit 111 estimates and outputs the friction estimation value as the characteristic estimation value E1 even if the type of the workpiece is changed, and stores and outputs the friction characteristic estimation value as the characteristic estimation value E1 immediately before the operation mode is changed to P2 without estimating the operation mode. Thus, the abnormality diagnosis unit 121 detects an abnormality when the variation of the estimated friction value, which is the characteristic estimated value E1, deviates from the allowable range with respect to the change of the type of the workpiece. With regard to the change of the operation mode, the variation due to the change of the operation mode is removed and the characteristic estimated value E1 is output, and the error detection of the abnormality due to the variation is not performed.
During such an operation, for example, during the periods 541 and 542, a drive mechanism component such as a slide rubber bush of a ball screw of the machining table is replaced by maintenance of the drive mechanism. Since the friction of the sliding rubber bushing after replacement varies among individuals, a criterion for abnormality diagnosis is established while performing a work operation after component replacement.
The abnormality reference creating unit 131 acquires and stores the characteristic estimated value E1 in accordance with the instruction of the abnormality reference creating instruction signal C3, and creates the abnormality diagnosis reference H1 based on the stored characteristic estimated value E1 if the total of the stored periods reaches a predetermined reference creating period.
Here, in the upper controller 200, the type of the workpiece used in the operation and the operation mode are known, and the abnormality reference creation instruction signal C3 is used as an instruction for creation when the type of the workpiece is W1 and the operation mode is P1, and is used as an instruction for not creating the workpiece (in the case where the workpiece is W3 and the operation mode is P2 in the example of fig. 7), and is used as an instruction which is not used for creation regardless of the operation condition after the total of the stored periods reaches the reference creation period (in the example of fig. 7, after the period 547). As for the abnormal reference creation instruction signal C3 of fig. 7, "creation" is illustrated in the case of an instruction for creation, and "interruption" is illustrated in the case of an instruction not for creation.
The abnormality reference creation instruction signal C3 is acquired from the host controller 200 outside the motor drive device 100 by the abnormality reference creation instruction acquisition unit 132 of the motor drive device 100. In the abnormal reference creating unit 131, the characteristic estimation value E1 is stored when the abnormal reference creating instruction signal C3 is an instruction for creating, and is not stored when the instruction for creating is not used. The storage of the characteristic estimation value E1 is performed until the abnormal reference creation instruction signal C3 is an instruction for creation and the total of the stored times or times becomes a reference creation period.
In fig. 7, in the periods 542, 544, and 546, since the type of the workpiece is W1 and the operation mode is P1, the abnormality reference creation instruction signal C3 is used as an instruction for creation, and the characteristic estimated value E1 is stored in the period. Since the sum of the times of the periods 542, 544, and 546 is the reference creation period, the storage is completed at the end of the period 546, and thereafter, the abnormal reference creation instruction signal C3 is also changed to an instruction not to be used for creation. The abnormality reference creating unit 131 calculates the average value and the standard deviation from the stored characteristic estimated value E1, calculates the upper limit and the lower limit of the allowable range as the abnormality diagnosis reference H1, and outputs the calculated upper limit and lower limit to the abnormality diagnosis unit 121. That is, in fig. 7, during period 547 and thereafter, an abnormality diagnosis is performed based on the abnormality diagnosis reference H1, and the result of the abnormality diagnosis is output as the abnormality determination signal F1.
In this way, the highly reliable abnormality diagnosis reference H1 based on the characteristic estimation is created and the abnormality diagnosis is performed based on the abnormality diagnosis reference H1 without being affected by changes in the operating conditions such as changes in the type of workpiece and changes in the operating mode.
That is, the motor drive device 100 according to embodiments 1 to 3 includes: an abnormality reference creation instruction acquisition unit 132 that acquires, from the outside, an abnormality reference creation instruction signal C3 that instructs, in accordance with the operating condition of the driving operation determined by the drive command signal Xr, whether or not to use the characteristic estimation value E1 for creating an abnormality diagnosis reference H1 for abnormality diagnosis; and an abnormality reference creating unit 131 that acquires the characteristic estimated value E1 from the characteristic estimating unit 111 when the abnormality reference creation instruction signal C3 is an instruction for creating, and does not acquire the characteristic estimated value E1 output from the characteristic estimating unit 111 when the abnormality reference creation instruction signal C3 is an instruction not for creating, and the abnormality reference creating unit 131 creates the abnormality diagnosis reference H1 for abnormality diagnosis based on the acquired characteristic estimated value E1 and outputs the abnormality diagnosis reference H1 to the abnormality diagnosing unit 121, so that it is possible to create the abnormality diagnosis reference H1 with high reliability based on the characteristic estimation without being affected by changes in the operation conditions such as changes in the operation mode and changes in the type of the workpiece, and to perform highly reliable abnormality diagnosis.
Further, since the abnormality reference H1 is created by the abnormality reference creation unit 131, the operator does not need to perform a measurement operation or the like and sets the abnormality diagnosis reference H1, which saves the operator's labor. Further, after the replacement of the components by maintenance or the like of the driving unit 300, it is not necessary to stop the operation of the driving unit 300 and perform the measurement operation or the like in order to reset the abnormality diagnosis reference H1, and the productivity of the driving unit 300 can be improved.
Further, although the example in which the abnormality reference creating unit 131 stores the characteristic estimated value E1 and then creates the abnormality diagnostic reference H1 using the stored characteristic estimated value E1 has been described, the abnormality diagnostic reference H1 may be created by sequentially performing update calculation on the abnormality diagnostic reference H1 based on the characteristic estimated value E1 without storing the characteristic estimated value E1 when the abnormality reference creation instruction signal C3 is an instruction for creation. Further, although the example in which the abnormality diagnosis criterion H1 is created using the average value, the standard deviation, the probability of occurrence of abnormality detection, and the normal distribution of the characteristic estimated value E1 has been described, the abnormality diagnosis criterion H1 may be created from the maximum value and the minimum value of the characteristic estimated value E1 in a fixed period.
In this way, when the abnormality diagnosis reference H1 is created, the abnormality diagnosis reference H1 with high reliability based on the characteristic estimation is created without being affected by changes in the operating conditions such as changes in the operating mode and changes in the type of workpiece, and the abnormality diagnosis is performed based on the abnormality diagnosis reference H1, so that the abnormality diagnosis with high reliability can be performed.
In embodiments 1 to 4, the example in which the driving mechanism 302 is a machining table that linearly drives the table by a ball screw or a machining tool held by a tool chuck has been described, but it may be a rotary driving mechanism that drives a gear mechanism combined with a spur gear or the like to rotate, a belt driving mechanism that drives a rotating shaft divided by a belt and a pulley, or the like.
Further, although the example in which the driving unit 300 includes the motor 301 and the driving mechanism 302 has been described, only the motor 301 may be provided.
The motor 301 has been described as a servo motor or an induction motor, but may be a reluctance motor, a linear motor that is not a rotary motor, or the like.
The detector 400 detects the position or speed of the motor 301, but may detect the position or speed of the driving mechanism 302. Instead of providing the detector 400, the position or speed of the motor 301 may be detected based on the current of the motor 301 in the motor drive device 100.
The characteristic estimated value E1 has been described using an example of a friction characteristic estimated value based on friction or a vibration amplitude characteristic estimated value based on speed deviation, but may be an estimated value of vibration amplitude or vibration frequency of any of position, speed, and current. The estimated value of the moment of inertia value of the motor 301 and the driving mechanism 302 may be used. That is, the characteristic estimated value E1 can use at least any one of coulomb friction, viscous friction, moment of inertia of the motor 301, vibration amplitude of the position of the motor 301, vibration frequency of the position, vibration amplitude of the speed of the motor 301, vibration frequency of the speed, vibration amplitude of the current of the motor 301, vibration frequency of the current, vibration amplitude of the torque of the motor 301, vibration frequency of the torque, and coulomb friction, viscous friction, and moment of inertia of the driving mechanism 302.
Further, although the example in which the characteristic estimation instruction signal C1, the abnormality diagnosis instruction signal C2, or the abnormality reference creation signal C3 is output from the external host controller 200 to the motor drive device 100 has been described, a signal based on a change in the operation conditions such as a change in the type of the workpiece may be acquired from an external workpiece supply device, and the characteristic estimation instruction signal C1 may be output from the workpiece supply device to the motor drive device 100. The characteristic estimation instruction signal C1, the abnormality diagnosis instruction signal C2, or the abnormality reference creating signal C3 may be transmitted through another device.
The operation in which the disturbance due to the cutting force during machining is present due to the command of the cutting movement in the machine tool has been described, but the operation in which the disturbance due to the gravity of the gripped weight is present while the robot grips the weight by the command of the gripping instruction may be performed by the operation in which the disturbance due to the impact force when the conveyance object is placed by the command of the conveyance driving mechanism.
In the present invention, the embodiments may be freely combined within the scope of the invention, and the embodiments may be appropriately modified or omitted.
Description of the reference numerals
1 motor drive system, 100 motor drive device, 101 drive control unit, 102 drive command acquisition unit, 103 drive detection value acquisition unit, 104 current detection unit, 111 characteristic estimation unit, 112 characteristic estimation instruction acquisition unit, 121 abnormality diagnosis unit, 122 abnormality diagnosis instruction acquisition unit, 131 abnormality reference creation unit, 132 abnormality reference creation instruction acquisition unit, 200 host controller, 300 drive unit, 301 motor, 302 drive mechanism, 400 detector.

Claims (11)

1. A motor drive device includes:
a drive detection value acquisition unit that acquires a drive detection value based on a position or a speed of a motor that drives a drive mechanism by the motor;
a drive command acquisition unit that acquires a drive command signal that is a target value of the drive detection value;
a drive control unit that performs a control operation so that the drive detection value follows the drive command signal, and causes the motor to perform a driving operation by causing a current to flow to the motor;
a characteristic estimation instruction acquisition unit that acquires, from outside, a characteristic estimation instruction signal that instructs whether or not to estimate a characteristic value of the motor or the drive mechanism based on an operation condition of the driving operation determined by the driving instruction signal; and
and a characteristic estimating unit that estimates the characteristic value based on a control state value used in the control calculation by the drive control unit when the characteristic estimation instruction signal is an instruction to estimate, outputs a characteristic estimation value, and does not estimate when the characteristic estimation instruction signal is an instruction to not estimate.
2. The motor drive device according to claim 1,
the characteristic estimation unit stores and outputs the characteristic estimation value before the instruction not to perform estimation, or outputs a predetermined value as the characteristic estimation value, when the characteristic estimation instruction signal indicates the instruction not to perform estimation.
3. The motor drive device according to claim 1 or 2,
an abnormality diagnosis unit is provided that performs an abnormality diagnosis of the motor or the drive mechanism based on the characteristic estimation value and outputs an abnormality determination signal.
4. A motor drive device includes:
a drive detection value acquisition unit that acquires a drive detection value based on a position or a speed of a motor that drives a drive mechanism by the motor;
a drive command acquisition unit that acquires a drive command signal that is a target value of the drive detection value;
a drive control unit that performs a control operation so that the drive detection value follows the drive command signal, and causes the motor to perform a driving operation by causing a current to flow to the motor;
a characteristic estimation unit that acquires a control state value used in the control calculation from the drive control unit, estimates a characteristic value of the motor or the drive mechanism, and outputs a characteristic estimation value;
an abnormality diagnosis instruction acquisition unit that acquires, from outside, an abnormality diagnosis instruction signal that instructs whether or not to perform an abnormality diagnosis based on the characteristic estimation value, based on an operating condition of the driving operation determined by the driving instruction signal; and
and an abnormality diagnosis unit that performs the abnormality diagnosis based on the characteristic estimation value of the characteristic estimation unit when the abnormality diagnosis instruction signal indicates an instruction to perform diagnosis, and outputs an abnormality determination signal, and does not perform the abnormality diagnosis when the abnormality diagnosis instruction signal indicates an instruction not to perform diagnosis.
5. The motor drive device according to claim 3 or 4, wherein:
an abnormality reference creation instruction acquisition unit that acquires, from outside, an abnormality reference creation instruction signal that instructs, based on the operating condition of the driving operation determined by the driving instruction signal, whether or not to use the characteristic estimation value for creating an abnormality diagnosis reference for the abnormality diagnosis; and
and an abnormality reference creation unit that acquires the characteristic estimation value from the characteristic estimation unit when the abnormality reference creation instruction signal is an instruction for creation, and does not acquire the characteristic estimation value output by the characteristic estimation unit when the abnormality reference creation instruction signal is an instruction for not creation, the abnormality reference creation unit creating the abnormality diagnosis reference for the abnormality diagnosis based on the acquired characteristic estimation value and outputting the abnormality diagnosis reference to the abnormality diagnosis unit.
6. The motor drive device according to any one of claims 1 to 5,
the characteristic estimation value is estimated from at least one of:
coulomb friction, viscous friction, and moment of inertia of the motor;
an amplitude of vibration of the location of the motor and a frequency of vibration of the location;
a vibration amplitude of the speed of the motor and a vibration frequency of the speed;
a vibration amplitude of the current of the motor and a vibration frequency of the current;
a vibration amplitude of a torque of the motor and a vibration frequency of the torque; and
coulomb friction, viscous friction, and moment of inertia of the drive mechanism.
7. The motor drive device according to any one of claims 1 to 6,
the drive command signal is the drive command signal in working operation.
8. The motor drive device according to any one of claims 1 to 7,
the operating condition includes at least one of an operating mode, a type of work, and an operation in which a disturbance is present.
9. An electric motor drive system having:
the motor drive device of claim 1; and
and an upper-level controller that outputs the drive command signal and the characteristic estimation instruction signal to the motor drive device.
10. An electric motor drive system having:
the motor drive device of claim 4; and
and a higher-level controller that outputs the drive command signal and the abnormality diagnosis instruction signal to the motor drive device.
11. An electric motor drive system having:
the motor drive device of claim 5; and
a higher-level controller that outputs the drive command signal and the abnormal reference creation instruction signal to the motor drive device.
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Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4557143B2 (en) * 2004-07-12 2010-10-06 日本精工株式会社 Power steering control device, method, and program
WO2013108356A1 (en) * 2012-01-16 2013-07-25 三菱電機株式会社 Motor controller
JP6014401B2 (en) * 2012-07-25 2016-10-25 東芝シュネデール・インバータ株式会社 Electric motor control device
CN106256084B (en) * 2014-04-22 2019-03-01 三菱电机株式会社 Control device of electric motor
RU2664031C1 (en) * 2015-01-26 2018-08-14 Ниссан Мотор Ко., Лтд. Electric motor vehicle control device and electric motor vehicle control method
JP6272548B2 (en) * 2015-02-27 2018-01-31 三菱電機株式会社 Electric motor control device
WO2017154476A1 (en) * 2016-03-08 2017-09-14 パナソニックＩｐマネジメント株式会社 Motor control device
JP6758141B2 (en) * 2016-09-26 2020-09-23 日本電産サンキョー株式会社 Motor control device
JP6769246B2 (en) * 2016-11-04 2020-10-14 株式会社デンソー Electric motor control device
JP6834601B2 (en) * 2017-03-02 2021-02-24 株式会社リコー Drive device, drive system, image forming device, transfer device, and drive method
JP6327541B1 (en) * 2017-03-27 2018-05-23 株式会社安川電機 Motor control system, motor control device, motor control method, and state estimation device
JP6571716B2 (en) * 2017-06-15 2019-09-04 ファナック株式会社 Evaluation program, information storage medium, evaluation method, and control apparatus

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