Anomaly detection method, anomaly detection system, sensor, and electronic device
The system allows sensors to perform mutual diagnosis, reducing reliance on microcontrollers and enhancing redundancy, addressing the challenges of high reliability and misdiagnosis in existing systems.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- ASAHI KASEI MICRODEVICES CORP
- Filing Date
- 2025-09-18
- Publication Date
- 2026-05-29
Smart Images
Figure 2026089013000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to an abnormality detection method, an abnormality detection system, a sensor, and an electronic device.
Background Art
[0002] Patent Document 1 describes that "the comparison unit 320 can detect an abnormality in the output of the magnetic sensor element 210 by comparing the input signal with a threshold value." (0052). [Prior Art Document] [Patent Document] [Patent Document 1] JP 2017-215307
Summary of the Invention
[0003] In a first aspect of the present invention, there is provided an abnormality detection method for detecting abnormalities of a plurality of sensors each individually packaged using a plurality of comparators. Each of the plurality of sensors has a sensor element for detecting current or magnetism, a signal processing circuit for processing a detection signal from the sensor element, and an input terminal to which detection signals of other sensors in the plurality of sensors are input. Each of the plurality of comparators corresponds to each of the plurality of sensors, compares a detection signal output from the signal processing circuit of the corresponding sensor with the detection signals of the other sensors, and the abnormality detection method includes comparing the detection signal of the corresponding sensor and the detection signals of the other sensors, and outputting an abnormality signal when a comparison result of the detection signal of the corresponding sensor and the detection signals of the other sensors does not satisfy a predetermined criterion.
[0004] The above abnormality detection method may further include determining a failure mode of the plurality of sensors based on a combination pattern of the output signals of the plurality of comparators, and determining a control mode of the plurality of sensors according to the failure mode.
[0005] In any of the above abnormality detection methods, each of the plurality of sensors may have a corresponding comparator among the plurality of comparators in the package.
[0006] In any of the above anomaly detection methods, two of the sensors may be arranged for a single phase current path. In any of the above anomaly detection methods, the comparison may include comparing the detection signal of the corresponding sensor with the detection signal of the other sensor with respect to the two sensors. In any of the above anomaly detection methods, the output may include outputting the anomaly signal with respect to the two sensors if the comparison result does not meet the criteria.
[0007] In any of the above anomaly detection methods, the comparison may include calculating the difference or sum of the detection signals of the corresponding sensors and the detection signals of the other sensor with respect to the two sensors. In any of the above anomaly detection methods, the output may include outputting the anomaly signal with respect to the two sensors if the difference or sum, which is the comparison result, does not meet the criteria.
[0008] In any of the above anomaly detection methods, three of the sensors may be arranged for a single phase current path. In any of the above anomaly detection methods, the comparison may include comparing the detection signal of the corresponding sensor with the detection signal of the other sensor for two of the three sensors. In any of the above anomaly detection methods, the output may include outputting the anomaly signal for two of the sensors if the comparison result does not meet the criteria.
[0009] In any of the above anomaly detection methods, one of the three sensors may be a comparison sensor. In any of the above anomaly detection methods, the comparison may include comparing the detection signal of the corresponding sensor with the detection signal of the other sensors for each of the two combinations of the comparison sensor and the remaining two sensors. In any of the above anomaly detection methods, the output may include outputting the anomaly signal for the two combinations if the comparison result does not meet the criteria. Any of the above anomaly detection methods may further include identifying which of the three sensors is abnormal based on which of the three sensors the anomaly signal was output from.
[0010] In any of the above anomaly detection methods, the three sensors may be arranged one for each of the three current paths. In any of the above anomaly detection methods, the input terminal of each of the three sensors may receive the detection signals of the other two sensors, and a corresponding comparator among the plurality of comparators may compare the detection signal of the corresponding sensor with the detection signals of the other two sensors. In any of the above anomaly detection methods, the comparison may include calculating the sum of the detection signals of the corresponding sensor and the detection signals of the other two sensors for the three sensors. In any of the above anomaly detection methods, the output may include outputting an anomaly signal for the three sensors if the sum, which is the comparison result, does not fall within a predetermined range, which is the criterion.
[0011] In any of the above anomaly detection methods, each of the plurality of sensors may further include a signal converter that performs signal processing on the detection signal of the corresponding sensor and the detection signal of the other sensors for comparison between the detection signal of the corresponding sensor and the detection signal of the other sensors by a corresponding comparator among the plurality of comparators. Any of the above anomaly detection methods may further include performing the signal processing on the detection signal of the corresponding sensor and the detection signal of the other sensors before the comparison.
[0012] In any of the above abnormality detection methods, the signal processing may include shifting the voltage of the detection signal of the corresponding sensor and the voltage of the detection signal of the other sensor to predetermined voltage levels.
[0013] In a second aspect of the present invention, an abnormality detection system is provided that detects abnormalities in a plurality of sensors, each individually packaged, using a plurality of comparators. The abnormality detection system comprises the plurality of sensors and the plurality of comparators, each of the plurality of sensors having a sensor element for detecting electric current or magnetism, a signal processing circuit for processing the detection signal from the sensor element, and an input terminal into which the detection signals of other sensors in the plurality of sensors are input, and each of the plurality of comparators corresponds to each of the plurality of sensors, compares the detection signal output from the signal processing circuit of the corresponding sensor with the detection signal of the other sensor, and outputs an abnormality signal if the comparison result does not meet a predetermined criterion.
[0014] The above-described anomaly detection system may further include a determination unit that determines the failure mode of the plurality of sensors based on the combination pattern of the output signals of the plurality of comparators, and determines the control mode of the plurality of sensors according to the failure mode.
[0015] A third aspect of the present invention provides a packaged sensor. The sensor comprises a sensor element that detects electric current or magnetism, a signal processing circuit that processes the detection signal from the sensor element, an input terminal that receives the detection signal from another packaged sensor, and a comparator that compares its own detection signal output from the signal processing circuit with the detection signal from the other packaged sensor and outputs an abnormal signal if the comparison result does not meet a predetermined standard.
[0016] A fourth aspect of the present invention provides an electronic device. The electronic device comprises a three-phase motor, a three-phase AC circuit, a three-phase current path electrically connecting the three-phase motor and the three-phase AC circuit, and the above-mentioned sensors, wherein two or more of the sensors are arranged for one of the three-phase current paths.
[0017] A fifth aspect of the present invention provides an electronic device. The electronic device comprises a three-phase motor, a three-phase AC circuit, a three-phase current path electrically connecting the three-phase motor and the three-phase AC circuit, and the above-mentioned sensors, with three of the sensors arranged one for each of the three-phase current paths.
[0018] It should be noted that the above summary of the invention does not enumerate all of its features. Furthermore, subcombinations of these features may also constitute an invention. [Brief explanation of the drawing]
[0019] [Figure 1] An example of the configuration of the anomaly detection system 11 according to the first embodiment is shown. [Figure 2] An example of the configuration of the anomaly detection system 12 according to the second embodiment is shown. [Figure 3] An example configuration of the anomaly detection system 13 according to the third embodiment is shown. [Figure 4] An example configuration of the electronic device 20 is shown. [Modes for carrying out the invention]
[0020] Hereinafter, the present invention will be described through embodiments of the invention. However, the following embodiments do not limit the invention according to the claims. Also, not all combinations of features described in the embodiments are essential for the solution of the invention.
[0021] FIG. 1 shows a configuration example of an abnormality detection system 11 according to the first embodiment. The abnormality detection system 11 includes a plurality of sensors 101, 102, 103, 104 each separately packaged, and uses a plurality of comparators 150 to detect abnormalities in the sensors 101 and the like. In FIG. 1, the abnormality detection system 11 is shown by a dashed frame. The same shall apply to the following figures, and redundant explanations will be omitted.
[0022] In the present embodiment, the abnormality detection system 11 inputs a detection signal of current or magnetism from the sensors 101 and the like to a microcomputer (microcontroller) 50. The microcomputer 50 performs feedback control on a device or the like connected to the microcomputer 50 according to the detection signal of the sensors 101 and the like of the abnormality detection system 11. The abnormality detection system 11 also inputs an abnormality signal of the sensors 101 and the like to the microcomputer 50.
[0023] The control target of the microcomputer 50 may be a motor, an actuator, a moving stage, an engine, or the like as long as it is a device that is controlled according to the detection signal of the sensors 101 and the like. In the present embodiment, the microcomputer 50 is connected to a three-phase motor M via an inverter circuit or the like, and controls the driving of the three-phase motor M by controlling the inverter circuit with a control signal according to the detection signal of the sensors 101 and the like. The microcomputer 50 can adjust the control of the three-phase motor M and the like in response to an abnormality signal being input from the sensors 101 and the like of the abnormality detection system 11. For example, it may execute protection control so that an excessive current does not flow through the three-phase motor M and the like, or may stop or interrupt the control of the three-phase motor M and the like.
[0024] In the abnormality detection system 11 of this embodiment, among the current paths Lu, Lv, and Lw connected to the U-phase, V-phase, and W-phase of the three-phase AC circuit C for supplying driving current to the three-phase motor M, two sensors 101 or the like are arranged in each of any two current paths. The three current paths Lu, Lv, and Lw electrically connect the three-phase motor M and the three-phase AC circuit C and are current paths for supplying driving current from the three-phase AC circuit C to the three-phase motor M. The abnormality detection system 11 uses a plurality of comparators 150 to diagnose the states of the two sensors 101 or the like for each phase, and when an abnormality is detected, outputs the above-described abnormality signal. More specifically, as an example, the abnormality detection system 11 diagnoses the states of the sensors 101 and 102 arranged in the current path Lu of the U-phase with respect to each other, and diagnoses the states of the sensors 103 and 104 arranged in the current path Lv of the V-phase with respect to each other. Such an abnormality detection system 11 may be referred to as a two-phase dual system abnormality detection system. In FIG. 1, only a part of the current paths Lu, Lv, and Lw are each indicated by a one-dot chain line, and the parts connected to the power supply, the three-phase motor M, etc. are omitted by a wavy line. Also, for the purpose of simply clarifying the explanation, the thicknesses of the current paths Lu, Lv, and Lw are shown differently. The same applies to the subsequent figures, and duplicate explanations are omitted.
[0025] Each of the plurality of sensors 101 or the like in this embodiment includes a sensor element 110, a signal processing circuit 120, an input terminal 130, a signal converter 140, a comparator 150, a first output terminal 161, and a second output terminal 162. The sensors 101 or the like may not include the signal converter 140. In this embodiment, as an example, a configuration is adopted in which each of the plurality of sensors 101 or the like includes a comparator 150 in the package, but alternatively, each comparator 150 may be provided separately from each sensor 101 or the like. In any case, a comparator 150 is provided for each sensor 101 or the like. That is, the comparator 150 only needs to correspond to each of the plurality of sensors 101 and may be outside the sensor 101.
[0026] The sensor element 110 detects electric current or magnetism. The sensor element 110 may be a resistance-type current sensor that detects electric current, or a magnetic field-type current sensor that detects magnetic fields. In this embodiment, the sensor element 110 is a magnetic field-type current sensor, such as a Hall element or a magnetoresistive element.
[0027] The sensor element 110 in this embodiment measures the magnetic field created by the current flowing through the current path Lu, etc. More specifically, the sensor element 110 outputs a detection signal that is proportional to the magnetic field created by the current flowing through the current path Lu, etc., that is, a voltage proportional to the amount of current flowing through the current path Lu, etc. In the abnormality detection system 11 of this embodiment, each sensor element 110 of sensors 101 and 102 outputs a detection signal that is proportional to the amount of current flowing through the current path Lu, and each sensor element 110 of sensors 103 and 104 outputs a detection signal that is proportional to the amount of current flowing through the current path Lv. In this embodiment, as an example, the sensor element 110 is configured to measure the magnetic field created by the current flowing through the current path Lu, etc., but the object of detection of current or magnetic field is not limited to the magnetic field created by the current flowing through the current path Lu. For example, the sensor element 110 may detect a magnetic field created by a magnetic field source other than the current path Lu, or a resistance detection type current sensor may be used to directly detect the current flowing through the current path Lu.
[0028] The signal processing circuit 120 processes the detection signal from the sensor element 110. The signal processing circuit 120 may, for example, reduce or remove element-specific offset signals that may be included in the detection signal from the sensor element 110 by methods such as the spinning current method or filtering, or it may amplify the intensity of the detection signal. The processed detection signal output from the signal processing circuit 120 is transmitted to the microcontroller 50 from the first output terminal 161 and is also input to the signal converter 140.
[0029] The input terminal 130 receives detection signals from multiple sensors 101, etc. In this embodiment, the input terminal 130 of sensor 101 receives the detection signal from sensor 102, which measures the magnetic field created by the current flowing through the current path Lu together with sensor 101, while the input terminal 130 of sensor 102 receives the detection signal from sensor 101. The input terminal 130 of sensor 103 receives the detection signal from sensor 104, which measures the magnetic field created by the current flowing through the current path Lv together with sensor 103, while the input terminal 130 of sensor 104 receives the detection signal from sensor 103.
[0030] The signal converter 140 performs signal processing on the detection signal output from the signal processing circuit 120 and the detection signal of other sensors 101, etc., input from the input terminal 130, for comparison by the comparator 150. For example, the signal converter 140 shifts the voltage of the detection signal output from the signal processing circuit 120 and the voltage of the detection signal of other sensors 101, etc., input from the input terminal 130, to predetermined voltage levels. In the following description, in order to distinguish between the detection signal output from the signal processing circuit 120, i.e., the detection signal based on the internal sensor element 110 of the sensor 101, etc., and the detection signal based on the external sensor element 110 of the sensor 101, etc., the former may be referred to as the signal converter's own detection signal and the latter as the other detection signal. The signal converter 140 inputs its own detection signal and the other detection signal, with their voltage levels shifted, to the comparator 150.
[0031] The comparator 150 compares its own detection signal with other detection signals. The comparator 150 outputs an abnormal signal if the comparison result between its own detection signal and other detection signals does not meet a predetermined standard.
[0032] In this embodiment, the comparator 150 of sensor 101 compares the detection signal of the sensor element 110 of sensor 101 with the detection signal of the sensor element 110 of sensor 102, and outputs an abnormal signal if the comparison result does not meet the criteria. More specifically, the comparator 150 of sensor 101 calculates the difference or sum of these two detection signals, and outputs an abnormal signal if the difference or sum does not meet the criteria.
[0033] For example, the comparator 150 may determine whether the difference between the voltage values of these two detection signals is zero, and output an abnormal signal if it is not zero, or it may determine whether the difference is greater than a predetermined range, and output an abnormal signal if it is greater than that range. For example, if the polarity of one of these two detection signals is reversed, the comparator 150 may determine whether the sum of the voltage values of these two detection signals is zero, and output an abnormal signal if it is not zero, or it may determine whether the sum is greater than a predetermined range, and output an abnormal signal if it is greater than that range.
[0034] At this time, the comparator 150 of sensor 101 and the comparator 150 of sensor 102 will emit the same signal. However, if either comparator 150 is faulty, it will emit a different signal. Therefore, the microcontroller 50, which acts as the decision-maker, will determine that there is a problem with the sensor element 110 or the signal processing circuit 120 if the comparator 150 of sensor 101 and the comparator 150 of sensor 102 both emit abnormal signals, and will determine that the signal from sensor 101, etc., cannot be used for control. On the other hand, if the outputs of the comparator 150 of sensor 101 and the comparator 150 of sensor 102 do not match, or if they both emit normal signals, the microcontroller 50, which acts as the decision-maker, will continue control using the signal from sensor 101, etc.
[0035] The abnormal signal output from comparator 150 is transmitted to the microcontroller 50 via the second output terminal 162. The comparators 150 for sensors 102, 103, and 104 function in the same way as the comparator 150 for sensor 101, and therefore redundant explanations are omitted.
[0036] In each of the multiple sensors 101, which are individually packaged, the sensor element 110, signal processing circuit 120, etc., are formed as individual electronic circuit elements, or some of them are formed together as an IC on a semiconductor substrate, and these are sealed with insulating resin with their terminals exposed. The sensor element 110, signal processing circuit 120, signal converter 140, and comparator 150 of each sensor 101 may be powered from a common power supply or from separate power supplies.
[0037] The configuration of the anomaly detection system 11 according to this embodiment has been described above with reference to Figure 1. As a first comparative example with the anomaly detection system 11 of this embodiment, we assume a system in which detection signals from multiple sensors are input to a diagnostic device equipped with a microcontroller, and the diagnostic device is made to diagnose anomalies in the multiple sensors. In the system of the first comparative example, high reliability is required for the diagnostic device of the microcontroller, and the fault diagnosis load on the microcontroller is large.
[0038] Furthermore, in the system of the first comparative example, the microcontroller diagnoses whether each sensor is normal or abnormal based on the detection signals from each sensor. However, in order to reliably prevent misdiagnosis, it is necessary to make the microcontroller redundant or to make the diagnostic process in the microcontroller redundant, which increases the number of components or increases the burden on the microcontroller.
[0039] As a second comparative example with the anomaly detection system 11 of this embodiment, we assume a system in which a comparator is provided on only a specific sensor among multiple sensors, for example, only one of a pair of sensors, and the comparator is made to compare the detection signal of that specific sensor with a predetermined reference value, and the anomaly diagnosis result of that specific sensor is considered to be the anomaly diagnosis result of all multiple sensors. In the system of the second comparative example, it is not possible to detect anomalies in sensors among multiple sensors that do not have a comparator, and the anomaly diagnosis result of all multiple sensors is uncertain. Furthermore, if there is only one comparator, it is not possible to know if the comparator has failed, and therefore it is not possible to know whether the anomaly diagnosis result is correct or incorrect.
[0040] As a third comparative example with the anomaly detection system 11 of this embodiment, we assume a system in which two sets of sensor elements and signal processing circuits are provided for all of the multiple sensors, and furthermore, a comparator is provided to compare the two sets of detection signals, allowing each sensor to self-diagnose whether or not there is an anomaly. In the system of the third comparative example, the circuit size of each sensor is large.
[0041] In contrast, the anomaly detection system 11 of this embodiment comprises a plurality of sensors 101, 102, 103, and 104, each individually packaged. Each of the plurality of sensors 101, etc., has a sensor element 110 that detects electric current or magnetism, a signal processing circuit 120 that processes the detection signal from the sensor element 110, an input terminal 130 into which the detection signals of other sensors 102, etc., are input, and a comparator 150 that compares its own detection signal output from the signal processing circuit 120 with the detection signals of other sensors 102, etc. The anomaly detection system 11 with this configuration compares its own detection signal with the detection signals of other sensors 102, etc., in the comparator 150 of each of the plurality of sensors 101, etc., and outputs an anomaly signal if the comparison result between its own detection signal and the detection signals of other sensors 102, etc., does not meet a predetermined standard. In other words, each of the plurality of sensors 101, etc., performs mutual diagnosis using its own detection signal and the detection signals of other sensors 102, etc. To put it another way, two or more sensors 101 perform mutual diagnosis with each other.
[0042] When comparing the anomaly detection system 11 of this embodiment with the system of the first comparative example, the system of the first comparative example has the microcontroller perform anomaly diagnosis of multiple sensors, but the anomaly detection system 11 of this embodiment does not have the microcontroller 50 perform such anomaly diagnosis, but rather has two or more sensors 101 perform mutual diagnosis with each other, thus ensuring redundancy independent of the microcontroller 50. According to the anomaly detection system 11 of this embodiment, anomaly detection can be performed on the side of the sensors 101, etc., so the microcontroller 50 only needs to be able to make a decision based on the diagnosis result. Furthermore, by utilizing the diagnostic function of the microcontroller 50, the diagnosis can be made redundant in conjunction with the sensors 101, etc., further improving the reliability of the judgment and reducing the load on the microcontroller 50. In addition, even if the comparator 150 becomes abnormal, misdiagnosis can be avoided, so the microcontroller 50 does not need to perform anomaly diagnosis and can simply make a decision based on the diagnosis result of the sensors 101, etc., thus reducing the load on the microcontroller 50.
[0043] When comparing the anomaly detection system 11 of this embodiment with the system of the second comparative example, the system of the second comparative example is configured such that a comparator is provided only on a specific sensor among multiple sensors, and the comparator compares the detection signal of that specific sensor with a predetermined reference value, and the anomaly diagnosis result of that specific sensor is considered to be the anomaly diagnosis result of all multiple sensors. In contrast, in the anomaly detection system 11 of this embodiment, each of the multiple sensors 101 etc. performs mutual diagnosis using its own detection signal and the detection signals of other sensors 102 etc. As a result, with the anomaly detection system 11 of this embodiment, no comparator is provided on any of the sensors 101 etc. to compare its own detection signal with a predetermined reference value, so the circuit size of each sensor 101 etc. can be reduced, thereby reducing the failure rate. Furthermore, with the anomaly detection system 11 of this embodiment, since all of the multiple sensors 101 etc. perform this mutual diagnosis, the anomaly diagnosis result of all of the multiple sensors 101 etc. is reliable.
[0044] When comparing the abnormality detection system 11 of this embodiment with the system of the third comparative example, the system of the third comparative example is provided with two sets of sensor elements and signal processing circuits for all of the multiple sensors, and furthermore, a comparator is provided to compare the two sets of detection signals, allowing each sensor to self-diagnose whether or not there is an abnormality. In contrast, the abnormality detection system 11 of this embodiment is provided with one set of sensor elements 110 and signal processing circuit 120 for each of the multiple sensors 101, and a comparator is provided to compare its own detection signal with the detection signals of other sensors 102 input from the input terminal 130, allowing the multiple sensors 101 to perform mutual diagnosis. As a result, the circuit size of each sensor 101 can be reduced according to the abnormality detection system 11 of this embodiment, thereby reducing the failure rate.
[0045] Figure 2 shows an example configuration of the anomaly detection system 12 according to the second embodiment. The anomaly detection system 12 according to the second embodiment differs from the anomaly detection system 11 according to the first embodiment in that it places three sensors 101, etc., for any single phase current path. More specifically, as an example, the anomaly detection system 12 places sensor 201 in addition to sensors 101 and 102 in the U phase current path Lu, and places sensor 202 in addition to sensors 103 and 104 in the V phase current path Lv.
[0046] The anomaly detection system 12 causes the three sensors 101 in each phase to diagnose each other's status and outputs an anomaly signal if an anomaly is detected. More specifically, the anomaly detection system 12 causes the two sensors 101 and 201 located in the U-phase current path Lu to diagnose each other's status, and the two sensors 102 and 201 located in the U-phase current path Lu to diagnose each other's status. The anomaly detection system 12 also causes the sensors 103 and 202 located in the V-phase current path Lv to diagnose each other's status, and the sensors 104 and 202 located in the V-phase current path Lv to diagnose each other's status.
[0047] Sensors 201 and 202 differ from sensors 101, etc., in that they have a first input terminal 231 and a second input terminal 232 instead of input terminal 130. Other configurations of sensors 201 and 202 are the same as the corresponding configurations of sensors 101, etc., therefore, the same reference numbers as those used for the corresponding configurations in sensors 101, etc., are used, and redundant explanations are omitted.
[0048] The first input terminal 231 of sensor 201 receives the detection signal from sensor 101. The second input terminal 232 of sensor 201 receives the detection signal from sensor 102. Since sensor 202 is the same as sensor 201, redundant explanations and detailed diagrams of its configuration are omitted. Similarly, in Figure 2, sensors 103 and 104 are the same as sensors 101 and 102, so redundant explanations and detailed diagrams of their configurations are omitted.
[0049] The comparator 150 of sensor 201 compares its own detection signal with the detection signal of the other sensor 101. The comparator 150 of sensor 201 also compares its own detection signal with the detection signal of the other sensor 102. For each of these comparisons, i.e., for each of the two combinations of sensor 201 and the two sensors 101 and 102, the comparator 150 of sensor 201 outputs an abnormal signal if the comparison result of its own detection signal and the other detection signals does not meet a predetermined standard. More specifically, for each of these comparisons, the comparator 150 of sensor 201 calculates the difference or sum of the two detection signals, similar to the comparator 150 of sensor 101, and outputs an abnormal signal if the difference or sum does not meet the standard. Further specific examples of the comparison of sensor 201 in comparator 150 include, for example, generating signal A by doubling the detection signal of sensor 201 in signal converter 140, and signal B by taking the sum of the detection signals of sensors 101 and 102, and then taking the difference between A and B in comparator 150. This is similar to the comparison in comparator 150 for sensor 101, and redundant explanations are omitted.
[0050] Unlike sensors 101 and others, sensor 201 is a comparison sensor. More specifically, the processed detection signal output from the signal processing circuit 120 of sensor 201 is not sent from the first output terminal 161 to the microcontroller 50, but is instead input to the respective input terminals 130 of sensors 101 and 102.
[0051] If sensor 101 malfunctions, both sensor 101 and sensor 201 will trigger an alarm. If sensor 102 malfunctions, both sensor 102 and sensor 201 will trigger an alarm. Similarly, if sensor 201 malfunctions, sensors 101, 102, and 201 will trigger an alarm. In this way, the microcontroller 50 can identify the malfunctioning sensor based on its alarm status. Therefore, the microcontroller 50 continues to control the system using the signals from the sensors that are not malfunctioning. If the three comparators 150 are functioning correctly, they will all produce the same output (diagnostic result). However, if a comparator is faulty, only that comparator's diagnostic result will trigger an alarm, indicating that the comparator is faulty. At this point, the microcontroller 50 determines that there is no malfunction in the sensor element 110 or the signal processing circuit 120, and continues to control the system using the signals from either sensor 101 or sensor 102.
[0052] The configuration of the abnormality detection system 12 according to this embodiment has been described above with reference to Figure 2. The abnormality detection system 12 according to this embodiment can identify a sensor that has become abnormal in one phase and can continue system operation using the remaining normal sensors, thus having the same or better effects than the abnormality detection system 11 according to the first embodiment.
[0053] According to the abnormality detection system 12 of this embodiment, as described above, three sensors 101, etc. are arranged in a single-phase current path, and a voltage detection signal proportional to the amount of current flowing through the current path is output from each of the three sensors 101, etc. Regarding the three sensors 101, 102, and 201 arranged in the current path Lu, the detection signal from sensor 201 is not input to the microcontroller 50, while the detection signals from sensors 101 and 102 are input to the microcontroller 50. On the other hand, abnormality signals are input to the microcontroller 50 not only from sensors 101 and 102, but also from sensor 201, via the second output terminal 162 from their respective comparators 150. Therefore, in this embodiment, the microcontroller 50 may determine which of the three sensors 101, 102, and 201 is abnormal based on which of the three sensors 101, 102, and 201 output the abnormality signal.
[0054] For example, if only sensor 101 is malfunctioning out of the three sensors 101, 102, and 201, the malfunction signal will be output from sensors 101 and 201, but not from sensor 102, so it can be identified that only sensor 101 is malfunctioning. For example, if only sensor 102 is malfunctioning out of the three sensors 101, 102, and 201, the malfunction signal will be output from sensors 102 and 201, but not from sensor 101, so it can be identified that only sensor 102 is malfunctioning. For example, if only sensor 201 is abnormal among the three sensors 101, 102, and 201, or if at least two of the three sensors 101, 102, and 201 are abnormal, abnormal signals will be output from all three sensors 101, 102, and 201. Therefore, it can be determined that only one of the two sensors 101 and 102 is not abnormal, and that either only sensor 201 is abnormal or at least two of the three sensors 101, 102, and 201 are abnormal.
[0055] If the microcontroller 50 determines that only one of the two sensors 101 and 102 is malfunctioning, it can continue controlling the drive of the three-phase motor M using the detection signals of the other sensor 101 and 102 and sensor 201. Furthermore, if the microcontroller 50 determines that only one of the two sensors 101 and 102 is malfunctioning, it can notify the user that only that sensor needs to be replaced.
[0056] Furthermore, this detection method is not limited to detecting the phase current of a three-phase motor, but can also be applied to detecting abnormalities when using multiple sensors 101, etc. In this embodiment as well, the microcontroller 50 itself does not need to perform abnormality diagnosis; it only needs to make decisions based on the abnormality diagnosis results of the sensors 101, etc., thus reducing the load on the microcontroller 50.
[0057] Figure 3 shows an example configuration of the anomaly detection system 13 according to the third embodiment. The anomaly detection system 13 according to the third embodiment differs from the anomaly detection system 11 according to the first embodiment in that it has three sensors 301, etc., one for each of the three phase current paths. More specifically, the anomaly detection system 13 has sensor 301 in the U phase current path Lu, sensor 302 in the V phase current path Lv, and sensor 303 in the W phase current path Lw.
[0058] The anomaly detection system 13 has three sensors 301, etc., located in each of the three phases, diagnose the status of each other, and outputs an anomaly signal if an anomaly is detected. Such anomaly detection system 12 is sometimes referred to as a three-phase single-duplex anomaly detection system.
[0059] Sensors 301, 302, and 303 differ from sensors 101, etc. in the first embodiment in that they have a first input terminal 331 and a second input terminal 332 instead of input terminal 130. Since the other configurations of sensors 301, 302, and 303 are the same as the corresponding configurations of sensors 101, etc., the same reference numbers as the corresponding configurations of sensors 101, etc. are used, and redundant explanations are omitted.
[0060] Sensor 301, etc., also differs from sensor 201, etc., in the second embodiment in that it is not a comparative sensor. That is, the processed detection signal output from the signal processing circuit 120 of sensor 301, etc., is transmitted from the first output terminal 161 to the microcontroller 50, and is also input to the first input terminal 331 and the second input terminal 332 of the other two sensors 302, etc.
[0061] The first input terminal 331 of sensor 301 receives the detection signal from sensor 302. The second input terminal 332 of sensor 301 receives the detection signal from sensor 303. Since sensors 302 and 303 are the same as sensors 301, redundant explanations will be omitted.
[0062] The comparator 150 of sensor 301 compares its own detection signal with the detection signals of the other two sensors 302 and 303. More specifically, the comparator 150 of sensor 301 calculates the sum of its own detection signal and the detection signals of the other two sensors 302 and 303, and outputs an abnormal signal if the sum does not fall within a predetermined range.
[0063] For example, the comparator 150 of the sensor 301 may determine whether the sum of the voltage values of these three detection signals is equivalent to 0A and output an abnormal signal if it is not equivalent to 0A, or it may determine whether the sum is greater than a predetermined range and output an abnormal signal if it is greater than that range.
[0064] The three comparators 150 for sensors 301, 302, and 303 emit the same signal. However, if any of the comparators 150 are faulty, they may emit a different signal from the two normal comparators 150. Therefore, by using this configuration, the microcontroller 50 can determine whether or not there is a malfunction in the comparators 150 and continue the abnormality diagnosis using the normal comparators 150.
[0065] The configuration of the anomaly detection system 13 according to this embodiment has been described above with reference to Figure 3. The anomaly detection system 13 according to this embodiment has the same effects as the anomaly detection system 11 according to the first embodiment.
[0066] According to the anomaly detection system 13 of this embodiment, as described above, one sensor 301 or the like is placed for each of the three phase current paths, and a voltage detection signal proportional to the amount of current flowing through each of the three phase current paths is output from each of the three sensors 301 or the like. In this way, the anomaly detection system 13 can mutually diagnose whether the sum of the detection signals from the three sensors 301, 302, and 303 is equivalent to 0A by utilizing the fact that the sum of the three phase currents is 0A.
[0067] In the abnormality detection system 13 according to this embodiment, it is possible to distinguish between abnormalities in the main circuit consisting of the sensor element 110 and the signal processing circuit 120 and abnormalities in the comparator 150. Therefore, the microcontroller 50 itself does not need to perform abnormality diagnosis, and can simply make decisions based on the abnormality diagnosis results of the sensor 101, etc., thereby reducing the load on the microcontroller 50.
[0068] The abnormality detection systems described in the above embodiments may be applicable not only to three-phase AC circuits but also to two-phase AC circuits and single-phase AC circuits. In a two-phase AC circuit, one sensor may be placed in each of the two phase current paths, and the two sensors may mutually diagnose whether the sum of the outputs of the two sensors is equivalent to 0A, by utilizing the fact that the sum of the currents of the two phases is 0A.
[0069] Figure 4 shows an example of the configuration of the electronic device 20. The electronic device 20 comprises a three-phase motor M, a three-phase AC circuit C, three-phase current paths Lu, Lv, and Lw that electrically connect the three-phase motor M and the three-phase AC circuit C, and a plurality of sensors 101, 201, 301, etc., as described using Figures 1 to 3. In an example of the electronic device 20, the plurality of sensors 101, 201, 301, etc. may be arranged in pairs or more for one phase of the three-phase current path Lu, etc., such as the plurality of sensors 101, 102, 103, 104 in the abnormality detection system 11 according to the first embodiment, or the plurality of sensors 101, 102, 103, 104, 201, 202 in the abnormality detection system 12 according to the second embodiment. In another example of the electronic device 20, the multiple sensors 101, 201, 301, etc., may be arranged in groups of three, one for each of the three-phase current paths Lu, etc., as in the multiple sensors 301, 302, 303 of the third embodiment. The electronic device 20 may also further include the microcontroller 50 described above, and the electronic device 20 and the microcontroller 50 may be separate entities that cooperate with each other. The electronic device 20 in this example also has the same effects as the abnormality detection systems 11, 12, and 13 of the multiple embodiments described above.
[0070] Although the present invention has been described above using embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various modifications or improvements can be made to the above embodiments. It will be clear from the claims that such modified or improved forms may also be included in the technical scope of the present invention.
[0071] It should be noted that the execution order of operations, procedures, steps, and stages in the apparatus, systems, programs, and methods shown in the claims, specifications, and drawings is not explicitly stated as "before," "prior to," etc., and that these can be implemented in any order unless the output of a previous process is used in a later process. Even if the operation flow in the claims, specifications, and drawings is described using phrases such as "first," "next," etc. for convenience, it does not mean that it is essential to perform the operations in that order. [Explanation of symbols]
[0072] C Three-phase AC circuit M Three-phase motor Hu, Lv, Lw current path 11 Anomaly detection system 50 Microcontrollers 101, 102, 103, 104 sensors 110 Sensor element 120 Signal Processing Circuits 130 Input Terminals 140 Signal Converters 150 comparators 161 First Output Terminal 162 Second Output Terminal 12 Anomaly detection system 201, 202 sensors 231 First Input Terminal 232 Second Input Terminal 13 Anomaly Detection System 301, 302, 303 sensors 331 First Input Terminal 332 Second Input Terminal 20 Electronic equipment
Claims
1. An anomaly detection method for detecting anomalies in multiple sensors, each individually packaged, using multiple comparators, Each of the aforementioned multiple sensors has a sensor element that detects electric current or magnetism, a signal processing circuit that processes the detection signal from the sensor element, and an input terminal into which the detection signals from other sensors in the multiple sensors are input. Each of the aforementioned comparators corresponds to each of the aforementioned sensors, and compares the detection signal output from the signal processing circuit of the corresponding sensor with the detection signal of the other sensors. Comparing the detection signal of the corresponding sensor with the detection signal of the other sensor, An abnormal signal is output if the comparison result between the detection signal of the corresponding sensor and the detection signal of the other sensor does not meet a predetermined standard. An anomaly detection method comprising the following features.
2. The system further comprises determining the failure mode of the plurality of sensors based on the combination pattern of the output signals of the plurality of comparators, and determining the control mode of the plurality of sensors according to the failure mode. The anomaly detection method according to claim 1.
3. Each of the aforementioned multiple sensors has a corresponding comparator from among the aforementioned multiple comparators within its package. The anomaly detection method according to claim 1.
4. Two of the aforementioned sensors are arranged for a single phase current path. The comparison described above includes, with respect to the two sensors, comparing the detection signal of the corresponding sensor with the detection signal of the other sensor. The output includes outputting the abnormal signal with respect to the two sensors if the comparison result does not meet the criteria. The anomaly detection method according to claim 1.
5. The comparison described above includes calculating the difference or sum of the detection signals of the corresponding sensors and the detection signals of the other sensors with respect to the two sensors. The output includes outputting the abnormal signal when the difference or sum, which is the comparison result, with respect to the two sensors does not meet the criteria. The abnormality detection method according to claim 4.
6. Three of the aforementioned sensors are arranged for a single phase current path. The comparison described above includes comparing the detection signals of the corresponding sensors with respect to two of the three sensors, and the detection signals of the other sensors. The output includes outputting the abnormal signal with respect to the two sensors if the comparison result does not meet the criteria. The anomaly detection method according to claim 1.
7. One of the three sensors mentioned above is a comparison sensor. The comparison described above includes comparing the detection signal of the corresponding sensor with the detection signal of the other sensors for each of the two combinations of the comparison sensor and the remaining two sensors among the three sensors. The output includes outputting the abnormal signal if the comparison result with respect to the two combinations does not meet the criteria, The system further includes identifying which of the three sensors is malfunctioning based on which of the three sensors the abnormal signal was output from. The abnormality detection method according to claim 6.
8. The three sensors are arranged one for each of the three current paths in the three-phase AC circuit. In each of the three sensors, the detection signals of the other two sensors are input to the input terminal, and the corresponding comparator among the plurality of comparators compares the detection signal of the corresponding sensor with the detection signals of the other two sensors. The comparison described above includes calculating the sum of the detection signals of the corresponding sensor and the detection signals of the other two sensors with respect to the three sensors. The output described above includes outputting the abnormal signal when the sum of the comparison results for the three sensors does not fall within the predetermined range that is the standard. The anomaly detection method according to claim 1.
9. Each of the aforementioned multiple sensors further includes a signal converter that performs signal processing on the detection signal of the corresponding sensor and the detection signal of the other sensors in order to compare the detection signal of the corresponding sensor with the detection signal of the other sensors using a corresponding comparator among the aforementioned multiple comparators. Prior to the comparison, the system further comprises performing the signal processing on the detection signal of the corresponding sensor and the detection signal of the other sensor. An anomaly detection method according to any one of claims 1 to 8.
10. The signal processing includes shifting the voltage of the detection signal from the corresponding sensor and the voltage of the detection signal from the other sensor to predetermined voltage levels. The abnormality detection method according to claim 9.
11. An anomaly detection system that uses multiple comparators to detect anomalies in multiple sensors, each individually packaged, The system comprises the aforementioned plurality of COMPERS and the aforementioned plurality of comparators, Each of the aforementioned multiple sensors has a sensor element that detects electric current or magnetism, a signal processing circuit that processes the detection signal from the sensor element, and an input terminal into which the detection signals from other sensors in the multiple sensors are input. Each of the aforementioned comparators corresponds to each of the aforementioned sensors, and compares the detection signal output from the signal processing circuit of the corresponding sensor with the detection signal of the other sensors, and outputs an abnormal signal if the comparison result does not meet a predetermined standard. Anomaly detection system.
12. The system further includes a determination unit that determines the failure mode of the plurality of sensors based on the combination pattern of the output signals of the plurality of comparators, and determines the control mode of the plurality of sensors according to the failure mode. The anomaly detection system according to claim 11.
13. A packaged sensor, A sensor element that detects electric current or magnetism, A signal processing circuit that processes the detection signal from the sensor element, An input terminal to which detection signals from other packaged sensors are input, A comparator that compares its own detection signal output from the signal processing circuit with the detection signal of the other packaged sensor, and outputs an abnormal signal if the comparison result does not meet a predetermined standard. A sensor equipped with the following features.
14. The system comprises a three-phase motor, a three-phase AC circuit, a three-phase current path electrically connecting the three-phase motor and the three-phase AC circuit, and the sensor described in claim 13. Two or more of the sensors are arranged in the current path of one of the three phases of the current path. electronic equipment.
15. The system comprises a three-phase motor, a three-phase AC circuit, a three-phase current path electrically connecting the three-phase motor and the three-phase AC circuit, and the sensor described in claim 13. The three sensors are arranged one for each of the three phase current paths. electronic equipment.