Abnormality detection device, abnormality detection method, and program

Abstract

To provide an abnormality detection device and the like capable of appropriately detecting an abnormality of a multiphase brushless motor.SOLUTION: An abnormality detection device that detects an abnormality of a multiphase brushless motor, includes: a calculation unit that calculates a value of a multiphase current sum of the multiphase brushless motor based on a detection value of a phase current value; and an abnormality detection unit that detects an abnormality of the multiphase brushless motor based on the value of the multiphase current sum calculated by the calculation unit. The abnormality detection unit detects an abnormality based on a period or the number of times when the value of the multiphase current sum calculated by the calculation unit exceeds a predetermined range.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an abnormality detection device, an abnormality detection method, and a program. [Background technology]

[0002] Patent Document 1 discloses that in a control device that performs vector control of a polyphase brushless motor, the control voltage at the point when half of the control period has elapsed is estimated based on the calculated rotor rotation speed, and a drive current is supplied to the coil based on the estimated control voltage. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6759041 Summary of the Invention [Problem to be solved by the invention]

[0004] In various devices using the above-mentioned multi-phase brushless motors, if an abnormality occurs in the multi-phase brushless motor, the motor cannot be controlled normally, which may cause problems in the operation of the device, etc. Therefore, it is necessary to properly detect abnormalities in the multi-phase brushless motor.

[0005] The present invention has been made to solve the above problems, and has an object to provide an abnormality detection device and the like that can appropriately detect an abnormality in a polyphase brushless motor. [Means for solving the problem]

[0006] In order to solve the above problem, one aspect of the present invention is to An abnormality detection device for detecting an abnormality in a polyphase brushless motor, a calculation unit that calculates a sum of the multi-phase currents of the multi-phase brushless motor based on the detected values ​​of the phase currents; an abnormality detection unit that detects an abnormality in the multi-phase brushless motor based on the value of the multi-phase current sum calculated by the calculation unit; The present invention provides an abnormality detection device comprising: [Effects of the Invention]

[0007] According to the present invention, an abnormality in a polyphase brushless motor can be appropriately detected. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram illustrating a configuration of a motor control device to which an abnormality detection device according to an embodiment of the present invention is applied. [Figure 2] 1 is a diagram illustrating a configuration of an abnormality detection device according to an embodiment of the present invention. [Figure 3] 4 is a flowchart illustrating an example of the operation of the abnormality detection device according to the present embodiment. [Figure 4] FIG. 10 is a diagram illustrating an example of a transition of a count value. [Figure 5] 10 is a diagram showing the relationship between each phase voltage value and the sum of three-phase currents, illustrating a case where the U-phase voltage value is stuck at the upper limit value. FIG. [Figure 5A] FIG. 10 shows the relationship between each phase voltage value and the sum of three-phase currents, illustrating a case where the U-phase voltage value is stuck at the reference voltage value (2.5V). [Figure 5B] FIG. 10 shows the relationship between each phase voltage value and the sum of three-phase currents, illustrating a case where the U-phase voltage value is stuck at the lower limit (0 V). [Figure 5C] 10 is a diagram showing the relationship between each phase voltage value and the sum of three-phase currents, illustrating a case where the U-phase voltage value is offset to the higher voltage side compared to the other phases. FIG. [Figure 5D] 10 is a diagram showing the relationship between each phase voltage value and the sum of three-phase currents, illustrating a case where the U-phase voltage value is offset to the lower voltage side compared to the other phases. FIG. [Figure 5E] 10 is a diagram showing the relationship between each phase voltage value and the sum of three-phase currents, in which the U-phase voltage value has a larger amplitude than the other phases. FIG. [Figure 5F]10 is a diagram showing the relationship between each phase voltage value and the sum of three-phase currents, illustrating a case where the U-phase voltage value has a smaller amplitude than the other phases. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0010] FIG. 1 is a diagram showing the configuration of a motor control device to which an abnormality detection device of this embodiment is applied, and FIG. 2 is a diagram showing the configuration of the abnormality detection device of this embodiment.

[0011] As shown in FIG. 1, a motor control device 20 to which the abnormality detection device 10 (FIG. 2) of this embodiment is applied performs vector control of a three-phase brushless motor 1 based on rotor rotational position information (motor angle information) detected by an angle detection unit 21 and the current values ​​of currents supplied to windings 6U, 6V, and 6W of each phase of the three-phase (U, V, and W phase) brushless motor 1.

[0012] Although a three-phase brushless motor 1 is exemplified in this embodiment, the number of phases of the brushless motor is arbitrary.

[0013] As shown in FIG. 1, the motor control device 20 includes an amplifier 22, a phase current calculation unit 23, a three-phase two-axis conversion unit 24, a target current calculation unit 26, a PI calculation unit 27, a two-axis three-phase conversion unit 28, and a drive unit 29.

[0014] Next, the operation of the motor control device 20 will be described.

[0015] The detected current values ​​(analog values) of the phase windings 6U, 6V, 6W of the three-phase brushless motor 1 are amplified by an amplifier 22, and the phase current values ​​of the three phases (UVW phases) are calculated in a phase current calculation unit 23.

[0016] The three-phase two-axis conversion unit 24 is provided with the three-phase phase current values ​​calculated by the phase current calculation unit 23 and the rotor rotational position information detected by the angle detection unit 21, and converts the three-phase phase current values ​​into d-axis current values ​​and q-axis current values ​​of two axes (d-axis, q-axis).

[0017] On the other hand, target current calculation unit 26 calculates a target d-axis current value and a target q-axis current value based on the target torque of three-phase brushless motor 1, and inputs them to PI calculation unit 27. PI calculation unit 27 performs proportional-integral calculation based on the deviation between the d-axis current value and q-axis current value from three-phase two-axis conversion unit 24 and the target d-axis current value and target q-axis current value, and outputs a d-axis command voltage value and a q-axis command voltage value.

[0018] The two-axis three-phase conversion unit 28 converts the d-axis command voltage value and the q-axis command voltage value from the PI calculation unit 27 into three-phase voltage values ​​based on the rotational position information of the rotor detected by the angle detection unit 21, and outputs them to the drive unit 29.

[0019] The drive unit 29 calculates the PWM duty value for each phase corresponding to the three-phase voltage values ​​from the two-axis three-phase conversion unit 28, and performs switching operations in accordance with the calculated PWM duty value for each phase, thereby supplying a predetermined amount of power to the phase windings 6U, 6V, and 6W.

[0020] By such operation of motor control device 20, the current values ​​of windings 6U, 6V, 6W of each phase of three-phase brushless motor 1 are feedback controlled, that is, the rotation of the rotor is vector controlled.

[0021] FIG. 2 is a diagram showing the configuration of the abnormality detection device of this embodiment.

[0022] As shown in FIG. 2, the abnormality detection device 10 includes a calculation unit 11 that calculates the value of the three-phase current sum by adding up the three-phase current values ​​acquired from the phase current calculation unit 23, and an abnormality detection unit 12 that detects an abnormality in the three-phase brushless motor 1 based on the value of the three-phase current sum calculated by the calculation unit 11.

[0023] The abnormality detection unit 12 can detect an abnormality based on the period or the number of times that the value of the three-phase current sum calculated by the calculation unit 11 exceeds a predetermined range.

[0024] FIG. 3 is a flowchart showing an example of the operation of the abnormality detection device of this embodiment, and FIG. 4 is a diagram showing an example of the transition of the count value.

[0025] 3, the calculation unit 11 periodically acquires three-phase current values ​​and calculates the value of the three-phase current sum. The abnormality detection unit 12 detects an abnormality based on the number of times (count value) that the value of the three-phase current sum exceeds a predetermined range during a predetermined period T (a period N times the control period), as calculated by the calculation unit 11.

[0026] In step S102, the count value is set to 0. This count value is a value that counts the number of times that the sum of the three-phase currents indicates an abnormal value that exceeds a predetermined range within a certain period of time.

[0027] In step S104, the calculation unit 11 waits for the start of the control cycle, acquires the current three-phase current values ​​from the phase current calculation unit 23, and calculates the value of the three-phase current sum (the sum of the three-phase current values) based on the acquired three-phase current values.

[0028] In step S106, the abnormality detection unit 12 determines whether the value of the current three-phase current sum calculated in step S104 indicates an abnormality, and stores the determination result. Here, an abnormality is determined when the value of the three-phase current sum calculated in step S104 is greater than the first abnormality determination threshold (FIG. 4) or less than the second abnormality determination threshold (FIG. 4). Note that, regarding the storage of the determination results, it is not necessary to retain determination results older than the determination results stored N times ago (step S106), which will be described later, and therefore unnecessary determination results may be deleted as appropriate.

[0029] In step S106A, if the determination result in step S106 indicates an abnormality, the abnormality detection unit 12 advances the process to step S108, and if the determination result in step S106 indicates a normality, the abnormality detection unit 12 advances the process to step S110.

[0030] In step S108, the abnormality detection unit 12 adds 1 to the count value, and the process proceeds to step S110.

[0031] In step S110, the abnormality detection unit 12 determines whether the judgment result (step S106) stored by the abnormality detection unit 12 N times ago indicates an abnormality, and if the judgment is positive, the process proceeds to step S111, and if the judgment is negative, the process proceeds to step S114. Here, the judgment is positive if the judgment result (step S106) stored N times ago indicates an abnormality, and the judgment is negative if the judgment result (step S106) stored N times ago is normal or if there is no judgment result (step S106) stored N times ago (the process of step S106 has not been repeated N+1 times).

[0032] In step S111, it is determined whether the count value is zero, and if the determination is affirmative, the process proceeds to step S104, and if the determination is negative, the process proceeds to step S112.

[0033] In step S112, the abnormality detection unit 12 subtracts 1 from the count value, and the process proceeds to step S104.

[0034] In step S114, the abnormality detection unit 12 determines whether the count value exceeds a predetermined abnormality count threshold (FIG. 4), and if the determination is affirmative, the process proceeds to step S116, and if the determination is negative, the process proceeds to step S104.

[0035] In step S116, the abnormality detection unit 12 notifies the abnormality determination result, executes a predetermined fail-safe operation, and ends the process.

[0036] As described above, in the process of FIG. 3, if the number of times (count number) that the judgment result indicates an abnormality in the most recent predetermined period T exceeds the abnormality count threshold (FIG. 4), the abnormality detection unit 12 notifies the abnormality judgment result indicating an abnormality and executes a predetermined fail-safe operation (step S116).

[0037] 3, an abnormality is determined when the number of times (count number) that the judgment result indicates an abnormality exceeds the abnormality count threshold (FIG. 4) during the most recent predetermined period T. This allows for reliable detection of abnormalities and avoids false detection of abnormalities.

[0038] 5 to 5F are diagrams showing the relationship between the phase voltage value of each phase and the sum of the three-phase currents.

[0039] 5 to 5F show the U-phase voltage value 5U, the V-phase voltage value 5V, the W-phase voltage value 5W, and the three-phase current sum. While Figures 5 to 5F illustrate an example in which an abnormality has occurred in the U-phase voltage value 5U, the three-phase current sum will change in the same way if an abnormality has occurred in the V-phase voltage value 5V or the W-phase voltage value 5W.

[0040] 5 shows a case where the U-phase voltage value 5U is stuck at the upper limit value. In this case, the value of the sum of the three-phase currents exceeds the second abnormality determination threshold, and an abnormality is detected.

[0041] 5A shows a case where the U-phase voltage value 5U is stuck at the reference voltage value (2.5 V). In this case, the sum of the three-phase currents alternates between normal and abnormal states.

[0042] 5B shows a case where the U-phase voltage value 5U is stuck at the lower limit value. In this case, the value of the sum of the three-phase currents exceeds the first anomaly determination threshold, and an anomaly is detected.

[0043] 5C shows a case where the U-phase voltage value 5U is offset to the higher voltage side compared to the other phases. In this case, an abnormality is detected when the value of the sum of the three-phase currents exceeds the second abnormality determination threshold.

[0044] 5D shows a case where the U-phase voltage value 5U is offset to the lower voltage side compared to the other phases. In this case, an abnormality is detected when the value of the sum of the three-phase currents exceeds the first abnormality determination threshold.

[0045] 5E shows a case where the U-phase voltage value 5U has a larger amplitude than the other phases, and the sum of the three-phase currents alternates between normal and abnormal states.

[0046] 5F shows a case where the U-phase voltage value 5U has a smaller amplitude than the other phases, and the sum of the three-phase currents alternates between normal and abnormal states.

[0047] As described above, according to this embodiment, it is possible to detect faults in various modes in the drive unit 29 (sticking of phase current values, offset, etc.) and abnormalities due to faults in other parts.

[0048] As described above, according to this embodiment, the value of the sum of the multi-phase currents of the multi-phase brushless motor is calculated based on the detected values ​​of the phase current values, and an abnormality in the multi-phase brushless motor is detected based on the calculated value of the sum of the multi-phase currents, so that an abnormality in the multi-phase brushless motor can be detected appropriately.

[0049] The following additional notes are provided regarding the above-described embodiments of the present invention.

[0050] [Appendix 1] An abnormality detection device for detecting an abnormality in a polyphase brushless motor, a calculation unit that calculates a sum of the multi-phase currents of the multi-phase brushless motor based on the detected values ​​of the phase currents; an abnormality detection unit that detects an abnormality in the multi-phase brushless motor based on the value of the multi-phase current sum calculated by the calculation unit; An abnormality detection device comprising:

[0051] According to the configuration described in Supplementary Note 1, the value of the sum of the multi-phase currents of the multi-phase brushless motor is calculated based on the detected values ​​of the phase current values, and an abnormality in the multi-phase brushless motor is detected based on the calculated value of the sum of the multi-phase currents, so that an abnormality in the multi-phase brushless motor can be appropriately detected.

[0052] [Appendix 2] 2. The abnormality detection device according to claim 1, wherein the abnormality detection unit detects the abnormality based on a period or number of times that the value of the multi-phase current sum calculated by the calculation unit exceeds a predetermined range.

[0053] According to the configuration described in Supplementary Note 2, an abnormality is detected based on the period or number of times that the value of the sum of the multi-phase currents exceeds a predetermined range. Therefore, by appropriately setting the period or number of times, it is possible to reliably detect an abnormality in the multi-phase brushless motor while avoiding erroneous detection.

[0054] [Appendix 3] the calculation unit periodically acquires the detected values ​​and calculates the value of the multi-phase current sum; 2. The abnormality detection device according to claim 1, wherein the abnormality detection unit detects the abnormality based on the number of times that the value of the sum of the multi-phase currents in a predetermined period of time calculated by the calculation unit exceeds a predetermined range.

[0055] According to the configuration described in Supplementary Note 3, an abnormality is detected based on the number of times that the value of the sum of the multi-phase currents exceeds a predetermined range during a predetermined period. Therefore, by appropriately setting the predetermined period and the number of times, it is possible to reliably detect an abnormality in the multi-phase brushless motor while avoiding erroneous detection.

[0056] [Appendix 4] An abnormality detection method for detecting an abnormality in a polyphase brushless motor, comprising: a calculation step of calculating a sum of the multi-phase currents of the multi-phase brushless motor based on the detected values ​​of the phase currents; an abnormality detection step of detecting an abnormality in the multi-phase brushless motor based on the value of the multi-phase current sum calculated in the calculation step; An anomaly detection method comprising:

[0057] According to the configuration described in Supplementary Note 4, the value of the sum of the multi-phase currents of the multi-phase brushless motor is calculated based on the detected values ​​of the phase current values, and an abnormality in the multi-phase brushless motor is detected based on the calculated value of the sum of the multi-phase currents, so that an abnormality in the multi-phase brushless motor can be detected appropriately.

[0058] [Appendix 5] A program for detecting an abnormality in a polyphase brushless motor, a calculation step of calculating a sum of the multi-phase currents of the multi-phase brushless motor based on the detected values ​​of the phase currents; an abnormality detection step of detecting an abnormality in the multi-phase brushless motor based on the value of the multi-phase current sum calculated in the calculation step; A program that causes a computer to execute the following.

[0059] According to the configuration described in Supplementary Note 5, the value of the sum of the multi-phase currents of the multi-phase brushless motor is calculated based on the detected values ​​of the phase current values, and an abnormality in the multi-phase brushless motor is detected based on the calculated value of the sum of the multi-phase currents, so that an abnormality in the multi-phase brushless motor can be appropriately detected. [Explanation of symbols]

[0060] 10. Anomaly detection device 11 Calculation section 12 Abnormality detection unit

Claims

1. An abnormality detection device for detecting an abnormality in a polyphase brushless motor, a calculation unit that calculates a sum of the multi-phase currents of the multi-phase brushless motor based on the detected values ​​of the phase currents; an abnormality detection unit that detects an abnormality in the multi-phase brushless motor based on the value of the multi-phase current sum calculated by the calculation unit; An abnormality detection device comprising:

2. The abnormality detection device according to claim 1 , wherein the abnormality detection unit detects the abnormality based on a period or number of times that the value of the sum of the multi-phase currents calculated by the calculation unit exceeds a predetermined range.

3. the calculation unit periodically acquires the detected values ​​and calculates the value of the multi-phase current sum; 2. The abnormality detection device according to claim 1, wherein the abnormality detection unit detects the abnormality based on the number of times that the value of the sum of the multi-phase currents in a predetermined period of time calculated by the calculation unit exceeds a predetermined range.

4. An abnormality detection method for detecting an abnormality in a polyphase brushless motor, comprising: a calculation step of calculating a sum of the multi-phase currents of the multi-phase brushless motor based on the detected values ​​of the phase currents; an abnormality detection step of detecting an abnormality in the multi-phase brushless motor based on the value of the multi-phase current sum calculated in the calculation step; An anomaly detection method comprising:

5. A program for detecting an abnormality in a polyphase brushless motor, a calculation step of calculating a sum of the multi-phase currents of the multi-phase brushless motor based on the detected values ​​of the phase currents; an abnormality detection step of detecting an abnormality in the multi-phase brushless motor based on the value of the multi-phase current sum calculated in the calculation step; A program that causes a computer to execute the following.

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