(19)
(11)EP 3 595 169 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
06.07.2022 Bulletin 2022/27

(21)Application number: 18763677.4

(22)Date of filing:  29.01.2018
(51)International Patent Classification (IPC): 
H02P 29/024(2016.01)
H02P 29/10(2016.01)
H02P 29/032(2016.01)
(52)Cooperative Patent Classification (CPC):
H02P 29/024; H02P 29/10; H02P 29/032
(86)International application number:
PCT/JP2018/002704
(87)International publication number:
WO 2018/163655 (13.09.2018 Gazette  2018/37)

(54)

MOTOR CONTROL DEVICE, MOTOR CONTROL SYSTEM, RUNAWAY STATE DETECTION METHOD, AND PROGRAM

MOTORSTEUERUNGSVORRICHTUNG, MOTORSTEUERUNGSSYSTEM, VERFAHREN ZUR ERKENNUNG DES DURCHGANGSZUSTANDS UND PROGRAMM

DISPOSITIF DE COMMANDE DE MOTEUR, SYSTÈME DE COMMANDE DE MOTEUR, PROCÉDÉ DE DÉTECTION D'ÉTAT D'EMBALLEMENT ET PROGRAMME


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 06.03.2017 JP 2017042178

(43)Date of publication of application:
15.01.2020 Bulletin 2020/03

(73)Proprietor: Omron Corporation
Kyoto-shi, Kyoto 600-8530 (JP)

(72)Inventor:
  • ONO, Yasushi
    Kyoto-shi Kyoto 600-8530 (JP)

(74)Representative: Becker Kurig & Partner Patentanwälte mbB 
Bavariastraße 7
80336 München
80336 München (DE)


(56)References cited: : 
JP-A- H01 120 607
JP-A- 2009 297 827
JP-A- 2010 250 509
JP-A- 2007 209 080
JP-A- 2010 172 117
US-A1- 2014 340 796
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    BACKGROUND


    [Technical field]



    [0001] The invention relates to a motor control device detecting runaway of a motor.

    [Description of Related Art]



    [0002] Because of reasons such as miswiring of a servomotor, the servomotor may fall into a runaway state in which the servomotor accelerates in a direction opposite to the command.

    [0003] A method of detecting such runaway is determining that the runaway state is present in the case where a torque command to the servomotor and the acceleration direction of the servomotor are different when the servomotor is accelerating. However, there is an issue that erroneous detection occurs in the case where the motor is moved by an offset or biased load.

    [0004] To address this issue, Patent Document 1 monitors the speed when the servomotor starts to accelerate, compares the speed with a displacement speed which is a peak speed, and updates the displacement speed and performs runaway detection of the servomotor if the speed is higher than the displacement speed. However, this method has issues such as unable to detect the runaway until the motor speed exceeds the peak speed, and time-consuming to detect the runaway particularly in the case where there is a large inertial load. In addition, there is a possibility that erroneous detection may occur even in the case where the oscillation of control instability occurs due to the gain setting of a controller. Patent Document 2 provides a robot controller capable of correctly and surely preventing a runaway of a robot joint and the whole robot without need of calculating and storing operation range data of each joint of the robot in advance even if an operation range or an operation track of the robot is momentarily changed and unknown load is suddenly applied. Patent Document 3 provides a control system for detecting the runaway after estimating the present motor position together with a time lag through simulation.

    [Related Art Document(s)]


    [Patent Document(s)]



    [0005] 

    Patent Document 1: Japanese Patent No. 3058360 A

    Patent Document 2: Japanese Patent No. 2009297827 A

    Patent Document 3: Japanese Patent No. 01120607 A


    SUMMARY


    Problem to be Solved



    [0006] The objective of the invention is to detect runaway of a motor in a short time while suppressing erroneous detection.

    [Means for Solving the Problems]



    [0007] To solve the above issue, the invention compares the sign of a jerk (also referred to as an acceleration change rate or a jerk degree) and the sign of a torque command differential value and determines that a runaway state is present in the case where a mismatch between the sign of the jerk and the sign of the torque command differential value continues for a predetermined time or more.

    [0008] Specifically, a motor control device according to an aspect of the invention is a motor control device generating a torque command, such that a detection speed of a motor matches a command speed, and controlling the motor, and includes: a torque command differential component taking a differential of the torque command and obtaining a torque command differential value; a motor actual speed second order differential component taking a second order differential of the detection speed of the motor and obtaining a motor jerk; and a runaway detection component determining that the motor is in a runaway state in a case where an abnormal state in which a sign of the motor jerk and a sign of the torque command differential value do not match continues for a predetermined time or more.

    [0009] In the case of a biased load, etc., even though it is possible that the signs of the torque command and the motor acceleration do not match even in a normal operation, the signs of the torque command differential value and the motor jerk match if the operation is normal. Therefore, the motor control device of the aspect can quickly detect the runaway of the motor without erroneous detection even in the case where a biased load is present.

    [0010] The runaway detection component of the aspect compares the signs of the torque command differential value and the motor jerk at a predetermined interval and can determine that the motor is in the runaway state in the case where a determination result of mismatch is repeatedly detected for a predetermined number of times. For example, in a case where the predetermined time is 10 milliseconds, it preferable that the determination on match/mismatch of signs is made every millisecond, and the runaway state is determined as present when the mismatch occurs ten consecutive times.

    [0011] It is preferable that, in the aspect, the runaway detection component also determines that the abnormal state is present in a case where a sign of a motor acceleration, which is a first order differential value of the motor, and a sign of the torque command do not match when the torque command is other than 0 and a differential value of the torque command is 0

    [0012] It is assumed that the torque command value is saturated in the runaway. In this case, the torque command differential value becomes 0, and the runaway cannot be detected by comparing the signs of the torque command differential value and the motor jerk. Therefore, in the case where the torque command is other than 0 and the torque command differential value is 0, it is preferable to detect the runaway according to the sign of the motor acceleration and the sign of the torque command. Since the state in which the motor acceleration and the torque command do not match despite that the torque is saturated is not a normal operation, an erroneous detection does not occur even in the determination based on the sign of the motor acceleration and the sign of the torque command when the torque is saturated.

    [0013] The runaway state detection component may also consider the abnormal state based on the mismatch between the sign of the torque command differential value and the sign of the motor jerk and the abnormal state based on the mismatch between the torque command and the motor acceleration when the torque command is saturated as the same abnormal state, and determine that the motor runs away in the case where one of the abnormal states is satisfied for the predetermined time or more. Alternatively, the runaway state detection component may consider the two runaway states as different and determine that the motor runs away in the case where one of the conditions continues for the predetermined time or more.

    [0014] It may also be that the runaway detection component of the aspect resets a duration of the abnormal state to zero in a case where the sign of the motor jerk and the sign of the torque command differential value match before the abnormal state has continued for the predetermined time or more. It may also be that the runaway detection component of the aspect resets a duration of the abnormal state to zero in a case where the sign of the motor acceleration and the sign of the torque command match when the torque command is other than 0 and the differential value of the torque command is 0 before the abnormal state has continued for the predetermined time or more.

    [0015] According to such configurations, the erroneous detections due to mismatch of signs resulting from accidentally occurring sign mismatches or noise, etc., can be eliminated.

    [0016] In the aspect, it is preferable that the torque command differential component and the motor actual speed second order differential component apply a low-pass filter for an input signal and obtain a differential value. In the case where the band of the differential component is not limited, the gain becomes higher as the frequency becomes higher, the noise increases, and the erroneous detection occurs more easily. By limiting the band of the differential signal by providing the low pass filter in the differential component, the erroneous detection caused by the noise generated through taking a differential can be suppressed.

    [0017] It is preferable that the motor control device in the aspect further includes an emergency stop component stopping the motor by at least one of cutting off current supply to the motor, using a dynamic brake, and setting the torque command to 0 when the runaway detection component detects the runaway state of the motor.

    [0018] According to such configuration, the motor can be stopped immediately when the runaway of the motor is detected.

    [0019] According to another aspect of the invention, a motor control device is a motor control device generating a torque command, such that a detection speed of a motor matches a command speed, and controlling the motor, and includes: a runaway state detection component determining that an abnormal state is present in a case where a sign of a motor jerk, which is a second order differential value of the detection speed of the motor, and a sign of a differential value of the torque command do not match, and determining that the motor is in a runaway state in a case where the abnormal state continues for a predetermined time or more.

    [0020] According to still another aspect of the invention, a motor control system includes a motor and the motor control system above.

    [0021] The invention can be construed as a motor control device having at least a portion of the functions. In addition, the invention can be construed as a control method executing at least a portion of the processes. Moreover, the invention can be construed as a computer program for executing the method in a computer or a computer readable storage medium non-transitory storing the computer program. Each component and process can be combined with each other within a possible extent to configure the invention.

    [Effects of invention]



    [0022] The motor control device can detect the runaway of the motor in a short time while suppressing the erroneous detection.

    BRIEF DESCRIPTION OF THE DRAWINGS



    [0023] 

    FIG. 1 is a block diagram of a motor control device in a first embodiment.

    FIG. 2 is a flowchart of a runaway state detection process in the first embodiment.

    FIG. 3A to FIG. 3E are diagrams describing runaway state detection in a case of miswiring in the first embodiment.

    FIG. 4A to FIG. 4E are diagrams describing runaway state detection in a case where a disturbance occurs in the first embodiment.

    FIG. 5 is a block diagram of a motor control device in a second embodiment.

    FIG. 6 is a flowchart of a runaway state detection process in the second embodiment.

    FIG. 7A to FIG. 7E are diagrams describing a runaway state detection process in the second embodiment.

    FIG. 8A is a diagram describing a differentiator in a third embodiment.

    FIG. 8B is a diagram describing an effect according to a low-pass filter of the differentiator in the third embodiment.

    FIG. 8C is a diagram describing a differentiator without a low-pass filter.


    DESCRIPTION OF THE EMBODIMENTS


    (First embodiment)


    [Configuration]



    [0024] FIG. 1 shows a schematic configuration of a motor control system in which a motor control device of the invention is installed. The motor system includes a motor control device 1, a motor 2 and an encoder 3. The motor control device 1 has a function of generating a torque command, such that the speed of the motor 2 matches a speed command from a controller (not shown), to control the motor 2 and detecting runaway of the motor 2. The motor 2 is installed in the device as an actuator of various machinery devices (e.g., arms and transfer devices of industrial robots) that are not shown herein. For example, the motor 2 is an AC motor. The encoder 3 is attached to the motor 2 to detect an operation of the motor 2. The encoder 3 includes location information concerning a rotational location (angle) of a rotational axis of the motor 2, information of a rotational speed of the rotational axis, etc. A general incremental encoder or an absolute encoder can be used as the encoder 3.

    [0025] A more specific configuration of the motor control device 1 is described. The motor control device 1 includes a speed command input part 11, a speed control part 12, a current controller 13, a speed detector 14, a torque command differentiator 15, a motor actual speed second order differentiator 16, a comparator 17, a runaway state detecting part 18, and a motor stop part 19. Among these configurations, the torque command differentiator 15, the motor actual speed second order differentiator 16, the comparator 17, and the runaway state detecting part 18 are functional parts for detecting the runaway of the motor 2.

    [0026] The speed command input part 11 receives a command speed of the motor 2 from a controller (not shown). The speed detector 14 obtains the actual speed (detection speed) of the motor 2 based on a feedback signal from the encoder 3. The speed control part 12 generates a torque command such that the command speed matches the detection speed. The current controller 13 turns on/off a switching element such as an IGBT based on the torque command to supply AC power to the motor 2.

    [0027] The torque command differentiator 15 receives the torque command generated by the speed control part 12 and calculates its differential value (first-order differential value). Hereinafter, the output of the torque command differentiator 15 is referred to as a torque command differential value.

    [0028] The motor actual speed second order differentiator 16 receives a motor actual speed output by the speed detector 14 and calculates its second order differential value. The second order differential of the speed (the first order differential of the acceleration) is referred to as jerk, jerk degree, acceleration change rate, etc. Hereinafter, the output of the motor actual speed second order differentiator 16 is referred to as a motor jerk.

    [0029] The comparator 17 receives the torque command differential value from the torque command differentiator 15 and the motor jerk from the motor actual speed second order differentiator 16, and determines whether the signs of these values match. The comparison result by the comparator 17 is input to the runaway state detecting part 18.

    [0030] The runaway state detecting part 18 uses the comparison result by the comparator 17 to determine whether the motor 2 is in the runaway state. Specifically, the runaway state detecting part 18 determines that an abnormal state is present in the case where the sign of the torque command differential value and the sign of the motor jerk do not match, and determines that the motor 2 is in the runaway state in the case where the abnormal state continues for a predetermined time or more. In addition, while FIG. 1 shows that only the comparison result of the comparator 17 is input to the runaway state detecting part 18, a torque command value or a motor actual speed (detection speed) is actually input. These pieces of information are also used to detect the runaway state of the motor 2. Details of the runaway state detection process are described below with reference to the flowchart.

    [0031] The torque command differentiator 15, the motor actual speed second order differentiator 16, the comparator 17 and the runaway state detecting part 18 may be implemented as digital circuits or analog circuits. Also, these functional parts may be realized by a combination of a digital signal processor (DSP), a field programmable gate array (FGPA), a microprocessor unit (MPU) and a program.

    [0032] When receiving a signal indicating that the runaway state has been detected from the runaway state detecting part 18, the motor stop part 19 puts an emergency stop on the motor 2. For example, the motor stop part 19 stops the motor 2 by one of cutting off the current supply from the current controller 13 to the motor 2, using a dynamic brake (regenerative brake), or setting the torque command to zero, or a combination of a plurality of the aforementioned.

    [Process]



    [0033] FIG. 2 is a flowchart showing a flow of the runaway state detection process by the runaway state detecting part 18. The process shown in FIG. 2 is executed periodically, and the execution interval thereof may be arbitrary, but, for example, can be set at about one millisecond.

    [0034] First, as a premise of the runaway state detection, the runaway state detecting part 18 confirms in Step S11 that the motor detection speed is equal to or higher than a first threshold (threshold 1) and in Step S12 that the torque command is equal to or higher than a second threshold (threshold 2). The determination in Step S11 is to confirm that the motor is in operation, and a sufficiently small value is set as the first threshold. The determination in Step S12 is a determination to avoid erroneous detection, and, for example, a value of about 10% of a rated torque is set as the second threshold.

    [0035] In the case where one of the determinations in Steps S11 and S12 is not satisfied (S11-NO or S12-NO), the process proceeds to Step S17, and the runaway state detecting part 18 sets an abnormal duration for counting the continuation of the abnormal state to zero.

    [0036] In the case where both of the determinations in Steps S11 and S12 are satisfied (S11-YES and S12-YES), the process proceeds to Step S13, and the runaway state detecting part 18 determines whether the sign of the torque command differential value and the sign of the motor jerk are different. This determination is made based on the output from the comparator 17.

    [0037] In the case where the sign of the torque command differential value and the sign of the motor jerk are different (S13-YES), the process proceeds to Step S14, and the runaway state detecting part 18 increases the abnormal duration. On the other hand, in the case where the sign of the torque command differential value and the sign of the motor jerk match (S13-NO), the process proceeds to Step S17, and the runaway state detecting part 18 resets the abnormal duration to zero.

    [0038] In Step S15, the runaway state detecting part 18 determines whether the abnormal duration is equal to or greater than a third threshold (predetermined time). The third threshold (threshold 3) is a time with which the motor can be determined as running away in the case where the mismatch between the sign of the torque command differential value and the sign of the motor jerk continues for the predetermined time or more. For example, 10 milliseconds (10 in the value of a counter) can be adopted as the third threshold.

    [0039] In the case where the abnormal duration is less than the third threshold (S14-NO), the runaway state detecting part 18 ends the process while holding the determination. On the other hand, in the case where the abnormal duration is greater than or equal to the third threshold (S14-YES), the process proceeds to Step S16, and the runaway state detecting part 18 determines that the motor 2 is in the runaway state. In the case where the runaway of the motor 2 is detected, the motor stop part 19 implements an emergency stop procedure of the motor 2.

    [Operation example]



    [0040] Detailed cases in the runaway state detection process are described with reference to FIG. 3A to FIG. 3E and FIG. 4A to FIG. 4E.

    [0041] FIG. 3A to FIG. 3E are diagrams respectively showing torque command value, motor acceleration, motor speed, torque command differential value, and motor jerk in the case where the connection between the motor control device 1 and the motor 2 is erroneous. In this case, the direction of the torque command and the rotational direction of the motor are opposite, and a speed control loop constitutes a positive feedback. Therefore, the torque command increases with time, and the speed of the motor 2 also increases in the opposite direction.

    [0042] In this embodiment, the runaway of the motor 2 can be detected quickly regardless of the size of the load inertia of the motor. The reason is that this embodiment does not require, as the condition for runaway detection, that the motor speed exceeds the peak speed, but sets a mismatch between the sign of the torque command differential value and the sign of the motor jerk as the condition. The sign of the torque command differential value and the sign of the motor jerk become different immediately after the motor is driven (T1), and therefore the runaway of the motor can be detected at T2 after the predetermined time has elapsed from T1.

    [0043] FIG. 4A to FIG. 4E are diagrams respectively showing torque command value, motor acceleration, motor speed, torque command differential value, and motor jerk in the case where a disturbance such as a biased load is present. In this example, it is assumed that the motor held by a brake, etc., is released from a holding state after driving starts, and acceleration is generated by the biased load.

    [0044] In the case where the biased load is present, there is a case where the sign of the torque command and the sign of the motor acceleration do not match. In the example of the figure, the sign of the torque command and the sign of the motor acceleration do not match in a period from driving to T3 and a period from T6 to T7. Therefore, in the case where runaway detection is performed based on the sign of the torque command and the sign of the motor acceleration, as in the prior art, there is a possibility that erroneous detection may occur.

    [0045] However, the sign of the torque command differential value and the sign of the motor jerk match in all periods. Therefore, even in the case where a disturbance, such as a biased load, is present, this embodiment can avoid erroneously detecting that the motor runs away even though the motor does not run away.

    [0046] As described above, according to the embodiment, the runaway can be detected quickly regardless of the load inertia of the motor, and the erroneous detection in the case where a disturbance occurs can be suppressed.

    (Second embodiment)


    [Configuration]



    [0047] The second embodiment makes it possible to detect runaway of a motor even when the torque command is saturated. FIG. 5 is a diagram showing a configuration of the motor control device 1 according to this embodiment. Among the functional parts shown in FIG. 5, those substantially identical to the functional parts shown in FIG. 1 are referred to with the same reference symbols, and the detailed description thereof is omitted.

    [0048] Compared with the first embodiment, the motor control device 1 according to this embodiment includes a motor actual speed first order differentiator 20 and a comparator 21.

    [0049] The motor actual speed first order differentiator 20 receives a motor actual speed output by the speed detector 14 and calculates its first order differential value. Hereinafter, the output of the motor actual speed first order differentiator 20 is referred to as motor acceleration.

    [0050] The comparator 21 receives the torque command value from the speed control part 12 and the motor acceleration from the motor actual speed first order differentiator 20, and determines whether the signs of these values match. The comparison result by the comparator 21 is input to the runaway state detecting part 18.

    [0051] The runaway state detecting part 18 in this embodiment receives a comparison result of the comparator 21 and the torque command differential value from the torque command differentiator 15 in addition to the comparison result of the comparator 17. The runaway state detection process in the runaway state detecting part 18 of this embodiment will be described with reference to FIG. 6.

    [Process]



    [0052] In the flowchart of FIG. 6, those substantially identical to the processes shown in FIG. 2 are referred to with the same reference symbols, and the detailed description thereof is omitted. In this embodiment, in the case where both of the determinations in Steps S11 and S12 are satisfied, the runaway state detecting part 18 determines in Step S18 whether the torque command differential value is zero. In the case where the torque command differential value is not zero (S 18-NO), the process proceeds to Step S13 and the same determination as in the first embodiment is performed. That is, if the sign of the torque command differential value and the sign of the motor jerk are different, it is determined that the abnormal state is present and the abnormal duration is increased, otherwise the abnormal duration is reset to zero.

    [0053] On the other hand, in the case where the torque command differential value is zero (S18-YES), the process proceeds to Step S19. In Step S19, the runaway state detecting part 18 uses the comparison result by the comparator 21 to determine whether the sign of the torque command value and the sign of the motor acceleration are different. Although the torque command is saturated, it cannot be said that the state in which the rotational direction of the motor is opposite to the command is a normal state. Therefore, in the case where these signs are different, it is determined that the abnormal state is present, and the process proceeds to Step S14 to increase the abnormal duration. On the other hand, in the case where these signs match, it is determined that the abnormal state is not present, and the process proceeds to Step S17 to reset the abnormal duration to zero. The subsequent processes are the same as those in the first embodiment.

    [Operation example]



    [0054] FIG. 7 A to FIG. 7E are diagrams respectively showing torque command value, motor acceleration, motor speed, torque command differential value, and motor jerk in the case where the torque command is saturated when the motor control device 1 and the motor 2 are incorrectly connected. Due to miswiring, the sign of the torque command differential value differs from the sign of the motor jerk. Here, it is assumed that the time until the torque command is saturated (time from T7 to T8) is shorter than the threshold time for runaway detection. After T8, since the differential value of the torque command becomes zero and therefore the motor jerk becomes zero, the runaway detection based on the signs of these values cannot be performed. However, in this embodiment, when the torque command differential value is zero, the sign of the torque command and the sign of the motor acceleration can be compared to detect the runaway of the motor.

    [0055] As described above, in this embodiment, even in the case where the torque command is saturated, the runaway of the motor can be reliably detected.

    [0056] In this embodiment, the runaway state detecting part 18 determines that the runaway state is present in the case where a state in which one of the determination of Step S13 and the determination of Step S19 is affirmed continues for the predetermined time or more. However, the runaway state detecting part 18 may also consider the state in which Step S13 is affirmed and the state in which Step S19 is affirmed as different abnormal states respectively and make a determination that the runaway state is present in the case where one of the abnormal states continues for the predetermined time or more.

    (Modified Example 1)



    [0057] Even though the examples of performing speed control on the motor have been described in the above embodiments, the motor control device may also perform location control. In addition, even though it is assumed that the motor control device 1 is a servo driver, the motor control device 1 may also be an inverter. As a motor driven by an inverter, an induction motor can serve as an example.

    (Modified Example 2)



    [0058] As the differentiator (the first order differential differentiator, the second order differentiator) in the above embodiments, as shown in FIG. 8A, a band limiting differentiator 80 consisting of a low-pass filter 81 and a differentiator 82 may also be adopted. The band limiting differentiator 80 can limit the band of the differentiator 82 by applying the low-pass filter for an input signal and obtaining the differential value. In the case where the band of the differentiator is not limited by the low-pass filter, as shown in FIG. 8C, the gain becomes higher as the frequency becomes higher, and the noise increases. Therefore, the erroneous detection of the runaway state occurs more easily. Regarding this, by limiting the band of the differentiator by the low-pass filter, as shown in FIG. 8B, the gain under a high frequency can be suppressed, and the noise can be reduced. Therefore, the occurrence of the erroneous detection of the runaway state due to the noise generated by taking a differential can be suppressed.

    [Description of Reference Numerals]



    [0059] 

    1: motor control device

    2: motor

    3: encoder

    11: speed command input part

    12: speed control part

    13: current controller

    14: speed detector

    15: torque command differentiator

    16: motor actual speed second order differentiator

    17: comparator

    18: runaway state detecting part

    19: motor stop part

    20: motor actual speed first order differentiator

    21: comparator




    Claims

    1. A motor control device (1), generating a torque command, such that a detection speed of a motor (2) matches a command speed, and controlling the motor (2), the motor control device (1) comprising:

    a torque command differential component (15) taking a differential of the torque command and obtaining a torque command differential value; and

    a motor actual speed second order differential component (16) taking a second order differential of the detection speed of the motor (2) and obtaining a motor jerk; the motor control device (1) being characterized in further comprising:
    a runaway detection component (18) determining that the motor (2) is in a runaway state in a case where an abnormal state in which a sign of the motor jerk and a sign of the torque command differential value do not match continues for a predetermined time or more.


     
    2. The motor control device (1) as claimed in claim 1, wherein the runaway detection component (18) resets a duration of the abnormal state to zero in a case where the sign of the motor jerk and the sign of the torque command differential value match before the abnormal state has continued for the predetermined time or more.
     
    3. The motor control device (1) as claimed in claim 1 or 2, wherein the runaway detection component (18) also determines that the abnormal state is present in a case where a sign of a motor acceleration, which is a first order differential value of the motor (2), and a sign of the torque command do not match when the torque command is other than 0 and the torque command differential value is 0.
     
    4. The motor control device (1) as claimed in claim 3,
    wherein the runaway detection component (18) resets a duration of the abnormal state to zero in a case where the sign of the motor acceleration and the sign of the torque command match when the torque command is other than 0 and the torque command differential value is 0 before the abnormal state has continued for the predetermined time or more.
     
    5. The motor control device (1) as claimed in any of claims 1 to 4, wherein the torque command differential component (15) and the motor actual speed second order differential component (16) apply a low-pass filter for an input signal and obtain a differential value.
     
    6. The motor control device (1) as claimed in any one of claims 1 to 5, further comprising:
    an emergency stop component (19) stopping the motor (2) by at least one of cutting off current supply to the motor (2), using a dynamic brake, and setting the torque command to 0 when the runaway detection component (18) detects the runaway state of the motor (2).
     
    7. A control system, comprising:

    a motor (2); and

    the motor control device (1) as claimed in any one of claims 1 to 6.


     
    8. A runaway state detection method, which is a runaway state detection method of a motor (2) performed by a motor control device (1) generating a torque command, such that a detection speed of the motor (2) matches a command speed, and controlling the motor, the runaway state detection method comprising following steps:

    taking a differential of the torque command and obtaining a torque command differential value; and

    taking a second order differential of the detection speed of the motor (2) and obtaining a motor jerk; the runaway state detection method being characterized in further comprising:
    determining that the motor (2) is in a runaway state in a case where an abnormal state in which a sign of the motor jerk and a sign of the torque command differential value do not match continues for a predetermined time or more.


     
    9. A computer program comprising instructions which, when the program is executed by a computer, cause the computer to carry out the method of claim 8.
     


    Ansprüche

    1. Motorsteuerungsvorrichtung (1), die einen Drehmomentbefehl erzeugt, so dass eine Erfassungsgeschwindigkeit eines Motors (2) mit einer Befehlsgeschwindigkeit übereinstimmt, und den Motor (2) steuert, wobei die Motorsteuerungsvorrichtung (1) umfasst:

    eine Drehmomentbefehl-Differentialkomponente (15), die ein Differential des Drehmomentbefehls nimmt und einen Drehmomentbefehl-Differentialwert erhält; und

    eine Differentialkomponente (16) zweiter Ordnung für die Ist-Motordrehzahl, die ein Differential zweiter Ordnung der Erfassungsdrehzahl des Motors (2) nimmt und einen Motorruck erhält; wobei die Motorsteuervorrichtung (1) dadurch gekennzeichnet ist, dass sie ferner umfasst:
    eine Durchgeh-Erfassungskomponente (18), die bestimmt, dass sich der Motor (2) in einem Durchgehzustand befindet, wenn ein abnormaler Zustand, in dem ein Zeichen des Motorrucks und ein Zeichen des Drehmomentbefehlsdifferentialwerts nicht übereinstimmen, für eine vorbestimmte Zeit oder länger fortgesetzt wird.


     
    2. Motorsteuerungsvorrichtung (1) gemäß Anspruch 1, wobei die Durchgeh-Erfassungskomponente (18) eine Dauer des abnormalen Zustands auf Null zurücksetzt, wenn das Zeichen des Motorrucks und das Zeichen des Drehmomentbefehlsdifferentialwerts übereinstimmen, bevor der abnormale Zustand für die vorbestimmte Zeit oder länger fortgesetzt wird.
     
    3. Motorsteuerungsvorrichtung (1) gemäß Anspruch 1 oder 2, wobei die Durchgeh-Erfassungskomponente (18) auch bestimmt, dass der abnormale Zustand in einem Fall vorliegt, in dem ein Zeichen einer Motorbeschleunigung, die ein Differentialwert erster Ordnung des Motors (2) ist, und ein Zeichen des Drehmomentbefehls nicht übereinstimmen, wenn der Drehmomentbefehl von 0 verschieden ist und der Drehmomentbefehl-Differentialwert 0 ist.
     
    4. Motorsteuerungsvorrichtung (1) gemäß Anspruch 3,
    wobei die Durchgeh-Erfassungskomponente (18) eine Dauer des abnormalen Zustands auf Null zurücksetzt, wenn das Zeichen der Motorbeschleunigung und das Zeichen des Drehmomentbefehls übereinstimmen, wenn der Drehmomentbefehl ungleich 0 ist und der Drehmomentbefehls-Differentialwert 0 ist, bevor der abnormale Zustand für die vorbestimmte Zeit oder länger fortgesetzt wird.
     
    5. Motorsteuerungsvorrichtung (1) gemäß einem der Ansprüche 1 bis 4, wobei die Drehmomentbefehl-Differentialkomponente (15) und die Motor-Ist-Drehzahl-Differentialkomponente zweiter Ordnung (16) einen Tiefpassfilter für ein Eingangssignal anwenden und einen Differentialwert erhalten.
     
    6. Motorsteuerungsvorrichtung (1) gemäß einem der Ansprüche 1 bis 5, ferner umfassend
    eine Notstoppkomponente (19), die den Motor (2) anhält, durch wenigstens eines von Unterbrechen der Stromzufuhr zu dem Motor (2), Verwenden einer dynamische Bremse und Setzen des Drehmomentbefehls auf 0, wenn die Durchgeherfassungskomponente (18) den Durchgehzustand des Motors (2) erfasst.
     
    7. Steuerungssystem, das umfasst:

    einen Motor (2); und

    die Motorsteuerungsvorrichtung (1) gemäß einem der Ansprüche 1 bis 6.


     
    8. Durchgehzustand-Erfassungsverfahren, das ein Durchgehzustand-Erfassungsverfahren eines Motors (2) ist, das von einer Motorsteuerungsvorrichtung (1) durchgeführt wird, die einen Drehmomentbefehl erzeugt, so dass eine Erfassungsgeschwindigkeit des Motors (2) mit einer Befehlsgeschwindigkeit übereinstimmt, und den Motor steuert, wobei das Durchgehzustand-Erfassungsverfahren die folgenden Schritte umfasst:

    Erfassen eines Differentials des Drehmomentbefehls und Nehmen eines Drehmomentbefehl-Differentialwerts; und

    Nehmen eines Differentials zweiter Ordnung der Erfassungsgeschwindigkeit des Motors (2) und Erhalten eines Motorrucks; wobei das Durchgehzustands-Erfassungsverfahren dadurch gekennzeichnet ist, dass es ferner umfasst:
    Bestimmen, dass sich der Motor (2) in einem Durchgehzustand befindet, wenn ein abnormaler Zustand, in dem ein Zeichen des Motorrucks und ein Zeichen des Drehmomentbefehl-Differentialwerts nicht übereinstimmen, für eine vorbestimmte Zeit oder länger fortgesetzt wird.


     
    9. Computerprogramm umfassend Befehle, die, wenn das Programm von einem Computer ausgeführt wird, den Computer veranlassen, das Verfahren gemäß Anspruch 8 auszuführen.
     


    Revendications

    1. Dispositif de commande de moteur (1), générant une instruction de couple, de sorte qu'une vitesse de détection d'un moteur (2) corresponde à une vitesse d'instruction, et commandant le moteur (2), le dispositif de commande de moteur (1) comprenant :

    un composant de différentiel d'instruction de couple (15) prenant un différentiel de l'instruction de couple et obtenant une valeur de différentiel d'instruction de couple ; et

    un composant de différentiel de second ordre de vitesse réelle de moteur (16) prenant un différentiel de second ordre de la vitesse de détection du moteur (2) et obtenant un à-coup de moteur ; le dispositif de commande de moteur (1) étant caractérisé en ce qu'il comprend en outre :
    un composant de détection d'emballement (18) déterminant que le moteur (2) est dans un état d'emballement dans un cas où un état anormal dans lequel un signe de l'à-coup de moteur et un signe de la valeur de différentiel d'instruction de couple ne correspondent pas continue pendant un temps prédéterminé ou plus.


     
    2. Dispositif de commande de moteur (1) selon la revendication 1, dans lequel le composant de détection d'emballement (18) réinitialise une durée de l'état anormal à zéro dans un cas où le signe de l'à-coup de moteur et le signe de la valeur de différentiel d'instruction de couple correspondent avant que l'état anormal ne continue pendant le temps prédéterminé ou plus.
     
    3. Dispositif de commande de moteur (1) selon la revendication 1 ou 2, dans lequel le composant de détection d'emballement (18) détermine également que l'état anormal est présent dans un cas où un signe d'une accélération de moteur, qui est une valeur de différentiel de premier ordre du moteur (2), et un signe de l'instruction de couple ne correspondent pas lorsque l'instruction de couple est autre que 0 et la valeur de différentiel d'instruction de couple est 0.
     
    4. Dispositif de commande de moteur (1) selon la revendication 3,
    dans lequel le composant de détection d'emballement (18) réinitialise une durée de l'état anormal à zéro dans un cas où le signe de l'accélération de moteur et le signe de l'instruction de couple correspondent lorsque l'instruction de couple est autre que 0 et la valeur de différentiel d'instruction de couple est 0 avant que l'état anormal ne continue pendant le temps prédéterminé ou plus.
     
    5. Dispositif de commande de moteur (1) selon l'une quelconque des revendications 1 à 4, dans lequel le composant de différentiel d'instruction de couple (15) et le composant de différentiel de second ordre de vitesse réelle de moteur (16) appliquent un filtre passe-bas pour un signal d'entrée et obtiennent une valeur de différentiel.
     
    6. Dispositif de commande de moteur (1) selon l'une quelconque des revendications 1 à 5, comprenant en outre :
    un composant d'arrêt d'urgence (19) arrêtant le moteur (2) par au moins l'un parmi la coupure de distribution de courant au moteur (2), l'utilisation d'un frein dynamique, et le réglage de l'instruction de couple à 0 lorsque le composant de détection d'emballement (18) détecte l'état d'emballement du moteur (2).
     
    7. Système de commande, comprenant :

    un moteur (2) ; et

    le dispositif de commande de moteur (1) selon l'une quelconque des revendications 1 à 6.


     
    8. Procédé de détection d'état d'emballement, qui est un procédé de détection d'état d'emballement d'un moteur (2) réalisé par un dispositif de commande de moteur (1) générant une instruction de couple, de sorte qu'une vitesse de détection du moteur (2) corresponde à une vitesse d'instruction, et commandant le moteur, le procédé de détection d'état d'emballement comprenant les étapes suivantes :

    la prise d'un différentiel de l'instruction de couple et l'obtention d'une valeur de différentiel d'instruction de couple ; et

    la prise d'un différentiel de second ordre de la vitesse de détection du moteur (2) et l'obtention d'un à-coup de moteur ; le procédé de détection d'état d'emballement étant caractérisé en ce qu'il comprend en outre :
    la détermination que le moteur (2) est dans un état d'emballement dans un cas où un état anormal dans lequel un signe de l'à-coup de moteur et un signe de la valeur de différentiel d'instruction de couple ne correspondent pas continue pendant un temps prédéterminé ou plus.


     
    9. Programme d'ordinateur comprenant des instructions qui, lorsque le programme est exécuté par un ordinateur, amènent l'ordinateur à réaliser le procédé selon la revendication 8.
     




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    Cited references

    REFERENCES CITED IN THE DESCRIPTION



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    Patent documents cited in the description