Method and apparatus for detecting fault of motor

Abstract

The present application relates to the technical field of vehicles, and provides a method and apparatus for detecting a fault of a motor. The method comprises: acquiring a first time period, a first position of a first device at a starting moment of the first time period, and a second position of the first device at an ending moment of the first time period, wherein the first device is driven by a motor; on the basis of the first position and the second position, determining a first position change amount; and on the basis of the first time period, the first position change amount, and a first correspondence, determining whether a fault occurs in the motor, the first correspondence being used for indicating a preset correspondence between the first position change amount and the first time period. The method can effectively improve the accuracy of motor fault detection, and can further detect faults other than motor stall faults, such as gear breakage in motors.

Description

Methods and apparatus for detecting motor faults

[0001] This application claims priority to Chinese Patent Application No. 202410684286.3, filed on May 29, 2024, entitled "Method and Apparatus for Detecting Motor Faults", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of vehicle technology, and specifically to methods and apparatus for detecting motor faults. Background Technology

[0003] With the continuous advancement of automotive technology, the ability to automatically fold or unfold rearview mirrors has become increasingly common. To achieve this, rearview mirrors require motor drive, enabling them to move within a preset range. However, during the automatic folding or unfolding process, the motor driving the mirror's movement may malfunction due to internal or external factors. For example, the mirror's rotating mechanism might be jammed by an external object, causing the motor to stall. Taking motor stall as an example, if it cannot be determined promptly and accurately whether the motor is stalled, it will continue to run in a stalled state. This not only causes the rearview mirror to remain stationary, reducing the driver's experience and safety, but if appropriate countermeasures are not taken in time, it may also damage the motor.

[0004] Therefore, how to detect whether the motor used to drive the rearview mirror is malfunctioning in a timely, accurate and comprehensive manner is an urgent problem to be solved. Summary of the Invention

[0005] This application provides a method and apparatus for detecting motor faults, which can effectively improve the accuracy of motor fault detection. Moreover, it is not limited to detecting motor stall faults, but can also detect other faults such as gear breakage in the motor.

[0006] In a first aspect, a method for detecting motor faults is provided. The method includes: acquiring a first time period, a first position of a first device at the start time of the first time period, and a second position at the end time of the first time period, wherein the first device is driven by a motor; determining a first position change based on the first position and the second position; and determining whether a motor fault has occurred based on the first time period, the first position change, and a first correspondence, wherein the first correspondence is used to indicate a preset correspondence between the first position change and the first time period.

[0007] For example, the first device mentioned above can be a vehicle's rearview mirror. Normally, the movement of a rearview mirror is rotation, so the first position change can be the angle of rotation of the rearview mirror during the first time period.

[0008] For example, the first correspondence can also be used to indicate the correspondence between other preset position changes and time periods. For instance, the first correspondence can be used to indicate the correspondence between the M positions that the first device passes through from the starting point to the end point and the movement time of the first device when the motor is running normally and continuously. The first position and the second position correspond to one of the M positions, where M is greater than 1.

[0009] It should be understood that the aforementioned first correspondence is the correspondence between the various moving positions of the first device and the time elapsed during the movement of the first device under ideal conditions, i.e., when the motor will not malfunction. The first time period, the first position, and the second position are parameters obtained by the controller from the first device after it has been put into use, under non-ideal conditions, i.e., when the motor may malfunction. Therefore, whether the motor has malfunctioned can be determined by whether the correlation between these three parameters matches at least part of the relationship represented by the aforementioned first correspondence.

[0010] For example, the aforementioned first correspondence can be obtained through prior experiments on the first device, and this first correspondence can be stored inside the controller. Furthermore, considering that there are various manufacturing processes for the first device, the first correspondence for the first device will differ depending on the manufacturing process.

[0011] Based on the above technical solution, by acquiring two positions of the first device during actual operation and the first time period experienced by the first device passing through these two positions, the correspondence between the first time period and the change in the first position during the actual movement of the first device is compared or matched with the correspondence between the first time period and the change in the first position during the ideal operation of the first device. Based on the comparison and matching results, it is determined whether the motor of the first device has failed. This eliminates the reliance on the setting of a current threshold for motor fault detection, thus avoiding the problem of inaccurate motor fault detection caused by an excessively large or small current threshold setting, and helping to improve the accuracy of motor fault detection. Especially when the first device is a vehicle rearview mirror, it can effectively improve the driving experience and safety of passengers, and reduce the need for high-precision current detection capabilities of the controller, thus helping to reduce manufacturing costs.

[0012] In conjunction with the first aspect, in some implementations of the first aspect, the change in the first position is matched with the preset change in the first position corresponding to the first time period in the first correspondence. If the change in the first position does not match the preset change in the first position, it is determined that the motor has malfunctioned; or, if the change in the first position matches the preset change in the first position, it is determined that the motor is operating normally.

[0013] For example, the aforementioned preset first position change can be obtained as follows: obtain the third position, which is the position corresponding to the first position among M positions in the first correspondence; then determine the fourth position based on the third position, the first time period, and the first correspondence, which is the position corresponding to the first device after moving from the third position for the first time period in the first correspondence; then, the position change from the third position to the fourth position is the aforementioned preset first position change.

[0014] For example, when the first device moves at a constant speed based on the motor-driven motion, the controller can match the position change of the first device with the calibrated position change in each fault detection cycle (e.g., the first time period mentioned above) to determine whether the motor of the first device has failed. In the case where the motor of the first device can have multiple operating speeds, the calibrated position change can be determined by the position change of the first device's motor driving the first device to move based on the slowest operating speed in the fault detection cycle.

[0015] Based on the above technical solution, by acquiring two positions of the first device during actual operation and the first time period experienced by the first device when passing through these two positions, the change in the first position of the first device during the first time period is matched with the preset change in the first position corresponding to the first time period during the first device's operation under ideal conditions. Based on the matching result, it is determined whether the motor of the first device has malfunctioned. This makes the process of detecting motor malfunctions no longer dependent on the setting of the current threshold, thereby avoiding the problem of inaccurate detection of motor malfunctions caused by the current threshold being set too high or too low, and helping to improve the accuracy of motor malfunction detection.

[0016] In conjunction with the first aspect, in some implementations of the first aspect, if the change in the first position is less than a preset change in the first position and the difference between the preset change in the first position and the change in the first position is greater than a preset first threshold, the fault of the motor is determined to be motor stall or motor clutch disengagement; or, if the change in the first position is greater than a preset change in the first position and the difference between the first change in the first position and the change in the first position is greater than a preset first threshold, the fault of the motor is determined to be motor gear breakage.

[0017] Based on the above technical solution, it is possible to detect a variety of motor faults, not only to detect whether the motor is stalled or the clutch is disengaged, but also to detect whether the motor has gear breakage and other faults, thus increasing the comprehensiveness of motor fault detection.

[0018] In conjunction with the first aspect, in some implementations of the first aspect, the first time period is matched with the preset first time period corresponding to the change in the first position in the first correspondence. If the first time period does not match the preset first time period, it is determined that the motor has malfunctioned; or, if the first time period matches the preset first time period, it is determined that the motor is operating normally.

[0019] Based on the above technical solution, by acquiring two positions of the first device during actual operation and the first time period experienced by the first device when passing through these two positions, the first time period experienced by the first device when moving from the first position to the second position is matched with the preset first time period experienced by the first device when moving from the first position to the second position under ideal conditions. Based on the matching result, it is determined whether the motor of the first device has failed. This makes the process of detecting motor faults no longer dependent on the setting of the current threshold, thereby avoiding the problem of inaccurate detection of motor faults caused by the current threshold being set too high or too low, and helping to improve the accuracy of motor fault detection.

[0020] In conjunction with the first aspect, in some implementations of the first aspect, if the first time period is longer than a preset first time period and the difference between the first time period and the preset first time period is greater than a preset second threshold, the fault of the motor is determined to be motor stall or motor clutch disengagement; or, if the first time period is shorter than a preset first time period and the difference between the preset first time period and the first time period is greater than a preset second threshold, the fault of the motor is determined to be motor gear breakage.

[0021] Based on the above technical solution, it is possible to detect a variety of motor faults, not only to detect whether the motor is stalled or the clutch is disengaged, but also to detect whether the motor has gear breakage and other faults, thus increasing the comprehensiveness of motor fault detection.

[0022] In conjunction with the first aspect, in some implementations of the first aspect, a first voltage value of the first device at the start of the first time period and a second voltage value at the end of the first time period are obtained; based on the first voltage value and the second voltage value, a first voltage change is determined, the first voltage change being used to indicate a first position change.

[0023] For example, a sliding rheostat is provided in the first device. When the first device is in different positions, the sliding rheostat can slide to the corresponding position so that the resistance value of the sliding rheostat is a specified value. The first voltage value and the second voltage value mentioned above can be understood as the real-time voltage value corresponding to the sliding rheostat.

[0024] For example, when the first device is in the first position, the sliding rheostat is located at position 1, and the real-time voltage value of the sliding rheostat is the first voltage value; when the first device moves to the second position, the sliding rheostat is located at position 2, and the real-time voltage value of the sliding rheostat is the second voltage value.

[0025] For example, the controller can determine the correspondence between the first position change and the first voltage change based on a second correspondence. This second correspondence indicates the correspondence between the voltage values ​​of the first device and the M positions it passes through from the starting point to the ending point when the motor is operating normally. It should be understood that the first and second positions correspond to one of the M positions, so the second correspondence can be used to indicate the correspondence between the first voltage value and the first position, and the correspondence between the second voltage value and the second position, so that the first voltage change can be used to indicate the first position change.

[0026] Based on the above technical solution, by pre-obtaining the correspondence between the voltage value and the position of the first device, the controller can determine the position of the first device by acquiring its voltage value during actual operation. This provides a prerequisite for determining whether the motor of the first device has malfunctioned based on its position change over a certain period. Furthermore, this method for obtaining the position of the first device is simple in principle; the frequency at which the controller acquires voltage values ​​is much lower than the frequency at which current is acquired in fault detection methods based on dynamic current thresholds, making it easy to implement and cost-effective.

[0027] In conjunction with the first aspect, in some implementations of the first aspect, the first voltage value is not equal to the second voltage value.

[0028] In conjunction with the first aspect, in some implementations of the first aspect, when the first voltage value and the second voltage value are equal to the first fixed voltage value, it is determined that the voltage value of the first device remains at the first fixed voltage value for a second period when the motor is running normally. If the first period is longer than the second period, it is determined that the motor is stalled; or, if the first period is shorter than or equal to the second period, it is determined that the motor is running normally.

[0029] Based on the above technical solution, it is possible to determine whether the motor has malfunctioned through multiple means, according to the first time period, the first position, the second position, and the first correspondence, thereby increasing the flexibility of the method for detecting motor malfunctions.

[0030] In conjunction with the first aspect, in some implementations of the first aspect, if the number of times the motor fails within a preset time period reaches N, the motor is controlled to stop operating, where N is a preset value and is a positive integer, and the preset time period is greater than or equal to the duration of the first time period.

[0031] Based on the above technical solution, the controller will only trigger the motor to stop operating when the number of times the motor malfunctions reaches N within a preset time period. This can effectively prevent the controller from directly controlling the motor to stop operating when it is mistakenly identified as a malfunctioning motor. Especially when the first device is a rearview mirror, it can effectively improve the driving experience of the driver and passengers.

[0032] Secondly, an apparatus for detecting motor faults is provided. The apparatus includes: an acquisition unit for acquiring a first time period, a first position of a first device at the start of the first time period, and a second position at the end of the first time period, the first device being based on a motor drive; and a determination unit for determining a first position change based on the first position and the second position; and determining whether a motor fault has occurred based on the first time period, the first position change, and a first correspondence, the first correspondence indicating a preset correspondence between the first position change and the first time period.

[0033] In conjunction with the second aspect, in some implementations of the second aspect, the aforementioned determining unit is specifically used to: match the first position change with the preset first position change corresponding to the first time period in the first correspondence; if the first position change does not match the preset first position change, determine that the motor has malfunctioned; or, if the first position change matches the preset first position change, determine that the motor is operating normally.

[0034] In conjunction with the second aspect, in some implementations of the second aspect, the aforementioned determining unit is specifically used to: determine that the motor fault is motor stall or motor clutch disengagement when the first position change is less than a preset first position change and the difference between the preset first position change and the first position change is greater than a preset first threshold; or, determine that the motor fault is motor gear breakage when the first position change is greater than a preset first position change and the difference between the first position change and the preset first position change is greater than a preset first threshold.

[0035] In conjunction with the second aspect, in some implementations of the second aspect, the aforementioned determining unit is specifically used to: match the first time period with the preset first time period corresponding to the first position change in the first correspondence; if the first time period does not match the preset first time period, determine that the motor has malfunctioned; or, if the first time period matches the preset first time period, determine that the motor is operating normally.

[0036] In conjunction with the second aspect, in some implementations of the second aspect, the aforementioned determining unit is specifically used to: determine that the motor fault is motor stall or motor clutch disengagement when the first time period is longer than a preset first time period and the difference between the first time period and the preset first time period is greater than a preset second threshold; or, determine that the motor fault is motor gear breakage when the first time period is shorter than a preset first time period and the difference between the preset first time period and the first time period is greater than a preset second threshold.

[0037] In conjunction with the second aspect, in some implementations of the second aspect, the aforementioned acquisition unit is specifically used to: acquire a first voltage value of the first device at the start time of the first time period and a second voltage value at the end time of the first time period; determine a first voltage change amount based on the first voltage value and the second voltage value, wherein the first voltage change amount is used to indicate a first position change amount.

[0038] In conjunction with the second aspect, in some implementations of the second aspect, when the determining unit matches the first position change with the preset first position change corresponding to the first time period in the first correspondence, or matches the first time period with the preset first time period corresponding to the first position change in the first correspondence, and the acquiring unit determines the position of the first device by the acquired voltage value, the first voltage value is not equal to the second voltage value.

[0039] In conjunction with the second aspect, in some implementations of the second aspect, where the above-mentioned acquisition unit determines the position of the first device by acquiring the voltage value, and the first voltage value and the second voltage value are equal to the first fixed voltage value, the above-mentioned determination unit is further specifically used to: determine a second time period in which the voltage value of the first device remains at the first fixed voltage value when the motor is running normally; if the first time period is longer than the second time period, determine that the motor is stalled; or, if the first time period is shorter than or equal to the second time period, determine that the motor is running normally.

[0040] In conjunction with the second aspect, in some implementations of the second aspect, the above-mentioned device further includes: a control unit, used to control the motor to stop operating when the number of times the motor malfunctions reaches N within a preset time period, where N is a preset value, N is a positive integer, and the preset time period is greater than or equal to the duration of the first time period.

[0041] Thirdly, an apparatus for detecting motor faults is provided, comprising a processor and a memory, wherein the processor and the memory are connected, wherein the memory is used to store program code, and the processor is used to call the program code to execute a method as described in any possible implementation of the method design in the first aspect above.

[0042] Fourthly, a controller is provided, including means as described in any possible implementation of the device design of the second or third aspect above.

[0043] In conjunction with the fourth aspect, in some implementations of the fourth aspect, the controller is applied to a vehicle, and the first device is the rearview mirror of the vehicle.

[0044] In conjunction with the fourth aspect, in some implementations of the fourth aspect, the aforementioned rearview mirror includes a sliding rheostat whose resistance value is associated with the position to which the rearview mirror is moved.

[0045] Fifthly, a vehicle is provided, including a device as in any possible implementation of the device design of the second or third aspect, or a controller as in any possible implementation of the controller design of the fourth aspect.

[0046] In a sixth aspect, a chip system is provided, which is applied to an electronic device; the chip system includes one or more interface circuits and one or more processors; the interface circuits and processors are interconnected via lines; the interface circuits are used to receive signals from the memory of the electronic device and send signals to the processor, the signals including computer instructions stored in the memory; when the processor executes the computer instructions, the electronic device executes any possible implementation of the method design of the first aspect above.

[0047] In a seventh aspect, a computer-readable storage medium is provided storing a computer program or instructions for implementing the method in any possible implementation of the method design of the first aspect.

[0048] Eighthly, a computer program product is provided, wherein when the computer program code or instructions are executed on a computer, the computer performs the method in any possible implementation of the method design of the first aspect described above. Attached Figure Description

[0049] Figure 1 is a schematic diagram of the system architecture of a system 100 for realizing the automatic folding or unfolding function of a rearview mirror;

[0050] Figure 2 is a flowchart illustrating a method 200 for detecting motor faults according to an embodiment of this application;

[0051] Figure 3 is a schematic diagram of a first correspondence relationship proposed in an embodiment of this application;

[0052] Figure 4 is a flowchart illustrating a method 400 for obtaining the location of a first device according to an embodiment of this application;

[0053] Figure 5 is a schematic diagram of a second correspondence relationship proposed in an embodiment of this application;

[0054] Figure 6 is a flowchart illustrating a method 600 for determining whether a motor has malfunctioned, as proposed in an embodiment of this application.

[0055] Figure 7 is a comparison diagram of the normal state and fault state of the motor of the first device proposed in the embodiments of this application;

[0056] Figure 8 is a flowchart illustrating another method 800 for determining whether a motor has malfunctioned, as proposed in an embodiment of this application.

[0057] Figure 9 is a comparison diagram of the normal state and fault state of the motor of another first device proposed in the embodiments of this application;

[0058] Figure 10 is a flowchart illustrating another method 1000 for determining whether a motor has malfunctioned, as proposed in an embodiment of this application.

[0059] Figure 11 is a schematic block diagram of a device 1100 for detecting motor faults provided in an embodiment of this application. Detailed Implementation

[0060] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0061] This application will present various aspects, embodiments, or features relating to a system comprising multiple devices, components, modules, etc. It should be understood and appreciated that individual systems may include additional devices, components, modules, etc., and / or may not include all the devices, components, modules, etc. discussed in conjunction with the accompanying drawings. Furthermore, combinations of these approaches are also possible.

[0062] Furthermore, in the embodiments of this application, the words "exemplary," "for example," etc., are used to indicate that they are examples, illustrations, or descriptions. Any embodiment or design scheme described as "exemplary" in the embodiments of this application should not be construed as being better or more advantageous than other embodiments or design schemes. Specifically, the use of the term "exemplary" is intended to present the concept in a concrete manner.

[0063] The business scenarios described in the embodiments of this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided in the embodiments of this application. As those skilled in the art will know, with the evolution of technology and the emergence of new business scenarios, the technical solutions provided in the embodiments of this application are also applicable to similar technical problems.

[0064] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0065] In this application embodiment, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0066] With the continuous advancement of automotive technology, the function of automatically folding or unfolding rearview mirrors in vehicles has gradually become more widespread.

[0067] Figure 1 is a schematic diagram of the system architecture of a system 100 for realizing the automatic folding or unfolding function of rearview mirrors.

[0068] This system 100 can be applied to vehicles. Referring to Figure 1, the vehicle's rearview mirror 110 is electrically connected to a motor 120, enabling the motor 120 to drive the rearview mirror 110 to automatically fold or unfold. However, the motor 120 cannot drive the rearview mirror 110 to move indefinitely. Therefore, the motor 120 also needs to be connected to a controller 130 so that it can receive control signals from the controller 130, allowing it to drive the rearview mirror 110 to move within a preset, reasonable range. Typically, the motor 120 is integrated into the rearview mirror 110.

[0069] It should be noted that the above system 100 is only an illustration, and the above system 100 can also be replaced by other system architectures with equivalent functions. The vehicle involved in the embodiments of this application is a vehicle with the above-mentioned automatic folding or unfolding function of the rearview mirror, or a vehicle with the mirror surface of the rearview mirror having a moving function. For ease of description, the embodiments of this application will be uniformly referred to as "vehicle".

[0070] The vehicles involved in this application may include road vehicles, water vehicles, air vehicles, industrial equipment, agricultural equipment, or entertainment equipment. For example, vehicles may include driverless vehicles. The term "vehicle" is used in a broad sense and can refer to vehicles (such as commercial vehicles, passenger cars, motorcycles, flying cars, trains, etc.), industrial vehicles (such as forklifts, trailers, tractors, etc.), engineering vehicles (such as excavators, bulldozers, cranes, etc.), agricultural equipment (such as lawnmowers, harvesters, etc.), amusement equipment, toy vehicles, etc. The embodiments of this application do not specifically limit the type of vehicle.

[0071] While the automatic folding or unfolding function of vehicle rearview mirrors provides convenience and enhances the driving experience, the motor driving the mirror's movement may malfunction due to internal or external factors during this process. For example, the mirror's rotation mechanism might be jammed by an external object, causing the motor to stall; the clutch within the motor might disengage; or the motor gears might break. If the vehicle cannot promptly and accurately determine whether a motor malfunction has occurred, it will lead to abnormal mirror movement, reducing both the driving experience and safety for passengers.

[0072] To address the aforementioned issues, two solutions have been proposed: a fault detection method based on a fixed current threshold and a fault detection method based on a dynamic current threshold. Both methods utilize the characteristic that the current in the motor circuit increases rapidly when the motor stalls.

[0073] The principle of the fault detection method based on a fixed current threshold is as follows:

[0074] Based on the current variation pattern of the circuit connected to the motor under different temperatures and voltages, a fixed current threshold is set. This current threshold is expected to be greater than all possible current values ​​of the motor during normal operation, but less than the current value of the motor when it is stalled.

[0075] However, the appropriateness of the current threshold setting depends on the thoroughness of the current detection experiments conducted on the motor circuit under different environmental factors before the motor is put into use. However, in reality, there are numerous possible combinations of temperature and voltage values, making it difficult to cover all possible scenarios through experimentation. Therefore, it is challenging to guarantee the appropriateness of the current threshold setting. If the current threshold is set too low, it may misjudge a stalled motor during normal operation; conversely, if the current threshold is set too high, it may misjudge a stalled motor as operating normally.

[0076] The fault detection method based on dynamic current threshold can monitor the motor current in real time while the motor is running, and dynamically adjust the current threshold according to parameters such as motor load and speed. The implementation principle of this method is as follows:

[0077] First, the motor's starting peak current is measured and recorded. This process is typically performed during motor startup and can be accomplished using specialized testing equipment or the motor control system. The starting peak current is the maximum current value the motor can reach at the moment of startup, and this peak current is used to set the subsequent current threshold. Then, based on the motor's rated current and the starting peak current, an initial current threshold is set. This threshold should not be too low to ensure that the protection mechanism is not triggered during normal motor startup, nor should it be too high to ensure timely response in case of motor stall. During motor operation, the current threshold is dynamically adjusted based on the actual motor current and load conditions. Then, the motor's real-time current is periodically monitored, and combined with parameters such as motor load and speed, to determine whether the motor is in a stall state that cannot be detected based on the current threshold alone. If stall is detected, the current threshold is appropriately lowered; if normal operation is detected, the current threshold is appropriately raised to improve the accuracy of stall detection. When the actual motor current exceeds the dynamically adjusted current threshold, the motor is considered stalled.

[0078] However, the implementation of fault detection methods based on dynamic current thresholds relies on the high-precision current detection and real-time monitoring capabilities of the motor controller. Furthermore, a detailed analysis of the motor's operating characteristics and load conditions is necessary to ensure the set current threshold is reasonable and effective. Therefore, this method places high demands on the controller's hardware capabilities; the controller must maintain a consistently high sampling rate for relevant motor parameters, typically requiring real-time current sampling once every 1ms, which increases the controller's manufacturing cost. Failure to meet this high sampling rate may lead to the current threshold being set too high or too low, increasing the probability of false alarms due to stall.

[0079] Furthermore, the two methods mentioned above can only detect motor stall faults, but cannot detect faults such as broken gears inside the motor, and there is no mechanism to prevent false alarms.

[0080] In view of this, the present application provides a method for detecting motor faults. This method does not rely on the motor current to determine whether the motor is stalled, but rather on the rate of change of the position of the rearview mirror driven by the motor to determine whether the motor is stalled. This method can effectively improve the accuracy of motor fault detection and is not limited to detecting motor stall faults, but can also detect other faults such as gear breakage in the motor.

[0081] Figure 2 is a flowchart illustrating a method 200 for detecting motor faults according to an embodiment of this application.

[0082] This method 200 can be executed by a controller connected to the motor, and includes the following steps:

[0083] S210: Obtain a first time period, a first position of a first device at the start of the first time period, and a second position of a first device at the end of the first time period, wherein the first device is motor driven.

[0084] In some possible embodiments, the first device mentioned above may be a rearview mirror of a vehicle. Typically, the movement of a rearview mirror is rotation, so the first position change may be the angle of rotation of the rearview mirror during a first time period.

[0085] In some possible embodiments, the movement of the rearview mirror may include not only rotation but also translation. Therefore, when the first device is a rearview mirror, the aforementioned first position change can be an angular change or a relative displacement change relative to a reference point; this application does not limit this.

[0086] S220: Determine the change in the first position based on the first position and the second position.

[0087] S230: Determine whether the motor has malfunctioned based on the first time period, the first position change, and the first correspondence. The first correspondence is used to indicate the preset correspondence between the first position change and the first time period.

[0088] In some possible embodiments, the aforementioned first correspondence is used to indicate a preset correspondence between the first position change and the first time period, which can be understood as the following two correspondences:

[0089] 1. The correspondence between the change in the first position and the preset first time period; wherein, the preset first time period is a pre-calibrated time period corresponding to the change in the first position, that is, the time period experienced by the first device from the first position to the second position under ideal conditions (normal motor operation).

[0090] 2. The correspondence between the first time period and the preset first position change amount; wherein, the preset first position change amount is the position change amount corresponding to the first time period, that is, the position change amount experienced by the first device from the first position based on the first time period under ideal conditions (normal motor operation).

[0091] In some possible embodiments, the first correspondence can also be used to indicate the correspondence between other preset position changes and time periods. For example, the first correspondence can be used to indicate the correspondence between the M positions that the first device passes through from the starting point to the end point and the movement time of the first device when the motor is running normally and continuously. The first position and the second position correspond to one of the M positions, where M is greater than 1.

[0092] Figure 3 is a schematic diagram of a first correspondence relationship proposed in an embodiment of this application.

[0093] In some possible embodiments, referring to Figure 3, the aforementioned first correspondence can be represented by an image within a coordinate system, where the x-axis represents the movement time of the first device and the y-axis represents the position of the first device. It should be understood that since the movement time of the first device is the time taken from the starting point to the ending point under the premise of normal continuous operation of the motor, the movement time of the first device refers to the time elapsed during the movement of the first device, during which there is no time for the first device to stop moving. The position of the first device can be the movement distance or rotation angle of the first device. Taking a rearview mirror as an example, the position of the first device can be represented by the rotation angle of the first device.

[0094] It should be noted that the first correspondence shown in Figure 3 is only an example. The corresponding first correspondence may be different for first equipment prepared by different processes or standards. For example, for other models of first equipment, the first correspondence may also be in the form of a direct proportional function. This application does not limit this.

[0095] Considering that the first device can move back and forth along a certain path based on motor drive—for example, if the first device is a rearview mirror, which can be extended or retracted based on motor drive—the extension and retraction of the rearview mirror constitutes a back-and-forth motion along a certain path. Therefore, Figure 3 shows two images: a solid line represents the forward movement of the first device along a certain path, and a dashed line represents the reverse movement of the first device along a certain path. It should be understood that the starting and ending points of the forward and reverse movements are interchanged. The method 200 proposed in this application is applicable to both scenarios where the first device moves forward and scenarios where the first device moves backward. Furthermore, the above-mentioned first correspondence can also be represented in other ways, which are not limited in this application.

[0096] For ease of description, the following embodiments of this application will use the forward movement of the first device as an example to describe in detail the method for detecting motor faults.

[0097] It should be understood that the aforementioned first correspondence is the correspondence between the various moving positions of the first device and the time elapsed during the movement of the first device under ideal conditions, i.e., when the motor will not malfunction. The first time period, the first position, and the second position are parameters obtained by the controller from the first device after it has been put into use, under non-ideal conditions, i.e., when the motor may malfunction. Therefore, whether the motor has malfunctioned can be determined by whether the correlation between these three parameters matches at least part of the relationship represented by the aforementioned first correspondence.

[0098] In some possible embodiments, the first correspondence described above can be obtained through prior experiments on the first device, and the first correspondence can be stored inside the controller.

[0099] In some possible embodiments, considering that there are various manufacturing processes for the first device, the first correspondence relationship for the first device will also differ depending on the manufacturing process. Taking a rearview mirror as an example, the first correspondence relationship may differ for different models of rearview mirrors.

[0100] Based on the above technical solution, by acquiring two positions of the first device during actual operation and the first time period experienced by the first device passing through these two positions, the correspondence between the first time period and the change in the first position during the actual movement of the first device is compared or matched with the correspondence between the first time period and the change in the first position during the ideal operation of the first device. Based on the comparison and matching results, it is determined whether the motor of the first device has failed. This eliminates the reliance on the setting of a current threshold for motor fault detection, thus avoiding the problem of inaccurate motor fault detection caused by an excessively large or small current threshold setting, and helping to improve the accuracy of motor fault detection. Especially when the first device is a vehicle rearview mirror, it can effectively improve the driving experience and safety of passengers, and reduce the need for high-precision current detection capabilities of the controller, thus helping to reduce manufacturing costs.

[0101] Figure 4 is a flowchart illustrating a method 400 for obtaining the location of a first device according to an embodiment of this application. The method 400 is illustrated using the example of obtaining the first time and the second time corresponding to the start and end times of a first time period, respectively. The method 400 includes the following steps:

[0102] S410: Obtain the first voltage value of the first device at the start time of the first time period and the second voltage value at the end time of the first time period.

[0103] In some possible embodiments, a sliding rheostat is provided in the first device. When the first device is in different positions, the sliding rheostat can slide to the corresponding position so that the resistance value of the sliding rheostat is a specified value. The first voltage value and the second voltage value mentioned above can be understood as the real-time voltage value corresponding to the sliding rheostat.

[0104] For example, when the first device is in the first position, the sliding rheostat is located at position 1, and the real-time voltage value of the sliding rheostat is the first voltage value; when the first device moves to the second position, the sliding rheostat is located at position 2, and the real-time voltage value of the sliding rheostat is the second voltage value.

[0105] S420: Determine a first voltage change based on a first voltage value and a second voltage value, the first voltage change being used to indicate a first position change.

[0106] In some possible embodiments, the time interval for the controller to acquire the voltage value of the first device may be 10ms. However, this does not mean that the aforementioned first time period is equal to 10ms. The aforementioned first time period may be the sum of multiple time intervals for acquiring voltage values, such as 400ms. In other words, the controller may execute the method for detecting motor faults proposed in this application embodiment once every 400ms. Of course, for controllers with different processing performance, the time interval for acquiring the voltage value of the first device can be adaptively adjusted, and the aforementioned first time period is similarly adjusted.

[0107] In some possible embodiments, the controller can determine the correspondence between the first position change and the first voltage change based on a second correspondence. This second correspondence indicates the correspondence between the voltage values ​​of the first device and the M positions traversed by the first device from the starting point to the ending point when the motor is operating normally. It should be understood that the first and second positions each correspond to one of the M positions, so the second correspondence can be used to indicate the correspondence between the first voltage value and the first position, and the correspondence between the second voltage value and the second position, so that the first voltage change can be used to indicate the first position change.

[0108] Figure 5 is a schematic diagram of a second correspondence according to an embodiment of this application. In the second correspondence shown in Figure 5, the first device is a rearview mirror.

[0109] In some possible embodiments, referring to FIG5, the above-mentioned first correspondence can be represented by an image in a coordinate system, wherein the x-axis of the coordinate system is the position (rotation angle) of the first device, and the y-axis is the voltage value of the first device.

[0110] In some possible embodiments, the second correspondence varies depending on the first device manufactured using different processes. Referring to Example 1 in Figure 5, the function graph between the position and voltage value of the first device represents a standard linear function relationship. Referring to Example 2 in Figure 5, the function graph between the position and voltage value of the first device represents a multi-segment function relationship, comprising three sequentially connected line segments, with the slope of the middle segment differing from the slopes of the two end segments. Referring to Example 3 in Figure 5, the function graph between the position and voltage value of the first device represents a multi-segment function relationship, comprising five sequentially connected line segments, where the slopes of segments 2 and 4 are 0, and the slope of segment 3 is also different from the slopes of segments 1 and 5. And so on.

[0111] Taking Example 3 in Figure 5 as an example, assuming the first voltage value is 3V and the second voltage value is 3.5V, then the corresponding first position is 85° and the second position is 95°; assuming the first voltage value is 0.6V and the second voltage value is 1V, then the corresponding first position is one of [20°, 35°] and the second position is 42°. Thus, in this case, the first voltage value corresponds to the horizontal segment (the slope of the line segment is 0) in the second correspondence image. Therefore, the exact position corresponding to the first position cannot be obtained at this time, only the possible position range of the first position can be obtained. How to determine whether the motor is faulty in this case will be explained in detail in the following content.

[0112] In some possible embodiments, similar to the first correspondence described above, the second correspondence can be obtained through prior experiments on the first device, and the second correspondence can be stored inside the controller.

[0113] Based on the above technical solution, by pre-obtaining the correspondence between the voltage value and the position of the first device, the controller can determine the position of the first device by acquiring its voltage value during actual operation. This provides a prerequisite for determining whether the motor of the first device has malfunctioned based on its position change over a certain period. Furthermore, this method for obtaining the position of the first device is simple in principle; the frequency at which the controller acquires voltage values ​​is much lower than the frequency at which current is acquired in fault detection methods based on dynamic current thresholds, making it easy to implement and cost-effective.

[0114] In some possible embodiments, the position of the first device described above can also be obtained by a position sensor, which can be a position sensor, a resistance strain gauge displacement sensor, an inductive displacement sensor, a grating displacement sensor, a rotary transformer, an angle sensor, etc.

[0115] To make it easier to understand, the following is a detailed explanation of how to determine if a motor has malfunctioned.

[0116] Figure 6 is a flowchart illustrating a method 600 for determining whether a motor has malfunctioned, as proposed in an embodiment of this application.

[0117] For example, when obtaining the position of the first device by method 400, method 600 is applicable to the case where the first voltage value and the second voltage value are not equal, that is, the first position change of the first device can be determined by the first voltage change, and the first voltage change is not equal to 0.

[0118] S610: Match the first position change with the preset first position change corresponding to the first time period in the first correspondence. If the first position change does not match the preset first position change, proceed to S620; otherwise, proceed to S630.

[0119] In some possible embodiments, the aforementioned preset first position change amount can be obtained in the following way: obtain a third position, which is the position corresponding to the first position among M positions in the first correspondence; taking the rearview mirror as an example, the first position is 50°, then the third position is 50° in the first correspondence; then, based on the third position, the first time period and the first correspondence, determine a fourth position, which is the position corresponding to the first device after moving from the third position for a first time period in the first correspondence; then, the position change amount from the third position to the fourth position is the aforementioned preset first position change amount.

[0120] S620: The motor has been identified as faulty.

[0121] S630: Confirm that the motor is operating normally.

[0122] In some possible embodiments, whether the above-mentioned first position change amount matches the preset first position change amount can be determined by the following formula (1): |△L2-△L1|>Q (1)

[0123] Wherein, △L1 is used to represent the first position change amount, △L2 is used to represent the preset first position change amount, and Q is used to represent the preset first threshold, which is greater than or equal to 0.

[0124] It should be understood that setting the first threshold to a value greater than 0 is to tolerate the detection error between the first and second positions. If the position obtained by the controller is guaranteed to be error-free, the first threshold can be set to 0.

[0125] When the conditions expressed by the above formula (1) are not met, it means that the motor is operating normally:

[0126] Assuming there is no error in the position obtained by the controller, for the motor to operate normally, the position change of the first device in the first time period should be equal to the position change of the first device in the first time period under ideal conditions. Therefore, |△L2-△L1|=0, which does not satisfy the condition expressed by the above formula (1).

[0127] When the conditions expressed by the above formula (1) are met, it means that the motor has failed:

[0128] Figure 7 is a comparison diagram of the normal state and fault state of the motor of a first device proposed in an embodiment of this application.

[0129] Referring to Figure 7, assuming the position obtained by the controller is error-free, for a motor stall or clutch disengagement fault, the change in the first position of the first device within the first time period should be less than the preset change in the first position compared to normal motor operation. Therefore, |△L2-△L1|>0, satisfying the condition expressed by formula (1) above. In other words, when |△L2-△L1|>0 and △L2>△L1, it can be determined that the motor has stalled or the clutch has disengaged.

[0130] Taking a rearview mirror as an example, if a motor experiences gear breakage, the fault manifests as the rearview mirror rapidly unfolding or popping open, with a drastic change in position within a short period. Compared to normal motor operation, the change in the first position of the first device within the first time period should be greater than the preset change in the first position. Therefore, |△L2-△L1|>0, satisfying the condition expressed by formula (1) above. In other words, if |△L2-△L1|>0 and △L2<△L1, it can be determined that the motor has experienced gear breakage.

[0131] In some possible embodiments, when the first device moves at a constant speed based on the motor-driven motion, the controller can match the position change of the first device with the calibrated position change in each fault detection cycle to determine whether the motor of the first device has failed. In cases where the motor of the first device can have multiple operating speeds, the calibrated position change can be determined by the position change of the first device's motor driving the first device to move within the fault detection cycle based on the slowest operating speed.

[0132] Taking the rearview mirror as an example, the fault detection cycle is the first time period in the above method 600, assuming the first time period is 400ms. Then, the controller determines the rotation angle of the rearview mirror every 400ms. Assuming the calibrated position change is 1.5°, if the rotation angle of the rearview mirror within 400ms is less than 1.5°, and the angle difference between it and 1.5° is greater than a preset angle threshold, it can be considered that the rearview mirror motor has stalled or the clutch has disengaged. If the rotation angle of the rearview mirror within 400ms is greater than 1.5°, and the angle difference between it and 1.5° is greater than a preset angle threshold, it can be considered that the rearview mirror motor has a gear breakage fault. If the angle difference between the rotation angle of the rearview mirror within 400ms and 1.5° is within a preset error range, it can be considered that the rearview mirror motor is operating normally.

[0133] In some possible embodiments, taking a rearview mirror as an example, considering that the rearview mirror's position is characterized by the voltage value corresponding to a sliding rheostat, if it is determined that the aforementioned first position change is mismatched with the preset first position change, it is also possible that the sliding rheostat has malfunctioned. For example, a foreign object may enter the sliding track of the rheostat, preventing further adjustment of the resistance value, thus leading to errors in the reporting of the first and second positions, and consequently, an incorrect first position change. Based on this, it can be seen that whether |△L2-△L1|>0 and △L2<△L1, or |△L2-△L1|>0 and △L2>△L1, it is possible that the sliding rheostat of the rearview mirror has malfunctioned.

[0134] Figure 8 is a flowchart illustrating another method 800 for determining whether a motor has malfunctioned, as proposed in an embodiment of this application.

[0135] For example, when obtaining the position of the first device by method 400, method 800 is applicable to the case where the first voltage value and the second voltage value are not equal, that is, the first position change of the first device can be determined by the first voltage change, and the first voltage change is not equal to 0.

[0136] S810: Match the first time period with the preset first time period corresponding to the first position change in the first correspondence. If the first time period does not match the preset first time period, proceed to S820; otherwise, proceed to S830.

[0137] In some possible embodiments, the aforementioned preset first time period can be obtained in the following way: obtain the third position and the fifth position, wherein the third position is the position corresponding to the first position among M positions in the first correspondence, and the fifth position is the position corresponding to the second position among M positions in the first correspondence; taking the rearview mirror as an example, the first position is 50°, the second position is 90°, then the third position is 50° in the first correspondence, and the fifth position is 90° in the first correspondence; then, based on the third position, the fifth position and the first correspondence, determine the time period experienced from the third position to the fifth position in the first correspondence, which is the aforementioned preset first time period.

[0138] S820: The motor has been identified as faulty.

[0139] S830: Confirm that the motor is operating normally.

[0140] In some possible embodiments, whether the above-mentioned first time period matches the preset first time period can be determined by the following formula (2): |△T2-△T1|>J (2)

[0141] Wherein, △T1 is used to represent the length of the first time period, △T2 is used to represent the preset length of the first time period, and J is used to represent the preset second threshold, which is greater than or equal to 0.

[0142] It should be understood that, similar to the first threshold, setting the second threshold to a value greater than 0 is to tolerate the detection errors of the first and second positions. If the position acquired by the controller is guaranteed to be error-free, the second threshold can be set to 0.

[0143] When the conditions expressed by the above formula (2) are not met, it means that the motor is operating normally:

[0144] Assuming there is no error in the position obtained by the controller, for the motor to operate normally, the length of the first time period during which the first device moves from the first position to the second position should be equal to the preset first time period during which the first device moves from the first position to the second position under ideal conditions. Therefore, |△T2-△T1|=0, which does not satisfy the condition expressed by the above formula (2).

[0145] When the conditions expressed in formula (2) above are met, it means that the motor has malfunctioned:

[0146] Figure 9 is a comparison diagram of the normal state and fault state of the motor of another first device proposed in the embodiments of this application.

[0147] Referring to Figure 9, assuming the position obtained by the controller is error-free, for a motor stall or clutch disengagement fault, compared to normal motor operation, the length of the first time interval during which the first device moves from the first position to the second position should be greater than the preset length of the first time interval. Therefore, |△T2-△T1|>0, satisfying the condition expressed by the above formula (2). In other words, when |△T2-△T1|>0 and △T2<△T1, it can be determined that the motor has stalled or the clutch has disengaged.

[0148] When a gear breaks in a motor, the first device will be quickly ejected within a short time. Therefore, compared to the normal operation of the motor, the length of the first time interval during which the first device moves from the first position to the second position should be less than the preset length of the first time interval. Thus, |△L2-△L1|>0, satisfying the condition expressed by the above formula (1). In other words, when |△T2-△T1|>0 and △T2>△T1, it can be determined that the motor has experienced a gear breakage fault.

[0149] In some possible embodiments, taking a rearview mirror as an example, considering that the rearview mirror's position is characterized by the voltage value corresponding to the sliding rheostat, if it is determined that there is a mismatch between the aforementioned first time period and the preset first time period, it is also possible that the sliding rheostat has malfunctioned, causing errors in the reporting of the first and second positions, and thus leading to an error in determining the change in the first position of the rearview mirror within the first time period. Based on this, it can be seen that whether |△T2-△T1|>0 and △T2<△T1, or |△T2-△T1|>0 and △T2>△T1, it is possible that the sliding rheostat of the rearview mirror has malfunctioned.

[0150] Figure 10 is a flowchart illustrating another method 1000 for determining whether a motor has malfunctioned, as proposed in an embodiment of this application. This method 1000 is applicable when the first voltage value and the second voltage value are equal, i.e., the first voltage value and the second voltage value are equal to a first fixed voltage value. Taking Example 3 in Figure 5 as an example, this situation occurs in the horizontal segment of the image. Therefore, the first position and the second position corresponding to these two voltage values ​​cannot be accurately determined based solely on the first voltage value and the second voltage value.

[0151] It should be noted that the first fixed voltage value can be a fixed value or a range of values. In particular, considering that there may be systematic errors in the first or second voltage value obtained, the first fixed voltage value can be a range of voltage values. For example, the first fixed voltage value is 4.5V, or it can be [4.4V, 4.6V]. As long as the obtained voltage value is within this range, it can be considered that the voltage value is equal to the first fixed voltage value, or the voltage value can be regarded as equal to 4.5V.

[0152] S1010: Determine that the voltage value of the first device is maintained at the first fixed voltage value for a second period when the motor is running normally. If the first period is longer than the second period, proceed to S1020; otherwise, proceed to S1030.

[0153] It should be noted that the first time period in method 1000 may be different from the first time period in method 600 or method 800. The first time period in method 600 or method 800 refers to the period during which the controller detects whether the motor has failed, such as 400ms. However, the first time period in method 1000 refers to the duration during which the controller acquires the voltage value of the first device as a first fixed voltage value during the actual movement of the motor, such as 1s. This means that the voltage values ​​acquired by the controller within 1s are all the first fixed voltage values.

[0154] In some possible embodiments, the first time period can be obtained as follows: when the voltage values ​​obtained by the controller at two consecutive moments are equal to the first fixed voltage value, the controller can obtain historical voltage data, which refers to all voltage values ​​of the first device obtained by the controller from the start of the current movement to the current moment. Then, multiple first fixed voltage values ​​are filtered out from the historical voltage data, as well as the time when the multiple first fixed voltage values ​​are obtained. Finally, the first time period is determined based on the maximum and minimum values ​​among the multiple times.

[0155] S1020: Confirmed that the motor is stalled.

[0156] S1030: Confirm that the motor is operating normally.

[0157] Taking line segment 2 in Example 3 of Figure 5 as an example, line segment 2 is a horizontal segment. Under normal motor operation, the time consumed by the first device to pass through the position corresponding to this horizontal segment is the second time period. If the time consumed by the first device to pass through the position corresponding to this horizontal segment (that is, the first time period) is greater than the second time period in actual operation, it means that the motor must have stalled during the first time period.

[0158] In some possible embodiments, taking a rearview mirror as an example, considering that the position of the rearview mirror is characterized by the voltage value corresponding to the sliding rheostat, when it is determined that the first time period is longer than the second time period, it is also possible that the sliding rheostat is malfunctioning, causing the voltage value obtained by the controller to be equal to the first fixed voltage value for a long time. However, in reality, the rearview mirror is still rotating based on the normal drive of the motor.

[0159] Based on the above technical solution, it is possible to determine whether a motor has malfunctioned through multiple methods, according to the first time period, the first position, the second position, and the first correspondence, thus increasing the flexibility of the method for detecting motor faults. Furthermore, this method can detect various motor faults, not limited to detecting whether the motor is stalled or the clutch is disengaged, but also capable of detecting faults such as gear breakage, increasing the comprehensiveness of motor fault detection.

[0160] In some possible embodiments, the controller typically determines motor faults within a very short period, usually set to 400ms. If the motor of the first device fails, the controller may determine the motor fault multiple times within a short preset time period (e.g., 2s); if the controller determines the motor fault only once within the preset time period, it indicates that the controller may have made a false fault determination during that preset time period, or that the voltage inside the first device is unstable, while the motor may be operating normally. Based on this, the method for detecting motor faults proposed in this application embodiment may further include the following steps:

[0161] If the number of times the motor fails reaches N within a preset time period, the motor will be controlled to stop running, where N is a preset value, N is a positive integer, and the preset time period is greater than or equal to the duration of the first time period.

[0162] For example, when the controller determines that the motor of the first device has failed during a first time period, the controller determines a preset time period based on the end time of the first time period and a preset duration. The start time of the preset time period is before the end time of the first time period, and the end time of the preset time period coincides with the end time of the first time period. If the controller determines that the number of times the motor has failed within the preset time period reaches N, it controls the motor to stop operating.

[0163] Based on the above technical solution, the controller will only trigger the motor to stop operating when the number of times the motor malfunctions reaches N within a preset time period. This can effectively prevent the controller from directly controlling the motor to stop operating when it is mistakenly identified as a malfunctioning motor. Especially when the first device is a rearview mirror, it can effectively improve the driving experience of the driver and passengers.

[0164] In some possible embodiments, when the controller stops the motor, a warning message may also be sent to indicate that the motor of the first device has malfunctioned.

[0165] Furthermore, embodiments of this application also provide an apparatus for implementing any of the above methods. For example, an apparatus for detecting motor faults is provided, which includes a unit (or means) for implementing any of the above methods for detecting motor faults.

[0166] Figure 11 is a schematic block diagram of a motor fault detection device 1100 provided in an embodiment of this application. This device 1100 can be applied to the aforementioned controller. The device 1100 includes:

[0167] The acquisition unit 1110 is used to acquire a first time period, a first position of a first device at the start time of the first time period, and a second position of a first device at the end time of the first time period, wherein the first device is based on motor drive;

[0168] The determining unit 1120 is used to determine the change in the first position based on the first position and the second position; and to determine whether the motor has malfunctioned based on the first time period, the change in the first position and the first correspondence relationship, wherein the first correspondence relationship is used to indicate the preset correspondence relationship between the change in the first position and the first time period.

[0169] In some possible embodiments, the determining unit 1120 is specifically used to: match the first position change with the preset first position change corresponding to the first time period in the first correspondence; if the first position change does not match the preset first position change, determine that the motor has malfunctioned; or, if the first position change matches the preset first position change, determine that the motor is operating normally.

[0170] In some possible embodiments, the determining unit 1120 is specifically used to: determine that the motor fault is motor stall or motor clutch disengagement when the first position change is less than a preset first position change and the difference between the preset first position change and the first position change is greater than a preset first threshold; or determine that the motor fault is motor gear breakage when the first position change is greater than a preset first position change and the difference between the first position change and the preset first position change is greater than a preset first threshold.

[0171] In some possible embodiments, the determining unit 1120 is specifically used to: match the first time period with the preset first time period corresponding to the first position change in the first correspondence; if the first time period does not match the preset first time period, determine that the motor has malfunctioned; or, if the first time period matches the preset first time period, determine that the motor is operating normally.

[0172] In some possible embodiments, the determining unit 1120 is specifically used to: determine that the motor fault is motor stall or motor clutch disengagement when the first time period is longer than the preset first time period and the difference between the first time period and the preset first time period is greater than the preset second threshold; or determine that the motor fault is motor gear breakage when the first time period is shorter than the preset first time period and the difference between the preset first time period and the first time period is greater than the preset second threshold.

[0173] In some possible embodiments, the acquisition unit 1110 is specifically used to: acquire a first voltage value of the first device at the start time of the first time period and a second voltage value at the end time of the first time period; determine a first voltage change amount based on the first voltage value and the second voltage value, wherein the first voltage change amount is used to indicate a first position change amount.

[0174] In some possible embodiments, when the determining unit 1120 matches the first position change amount with the preset first position change amount corresponding to the first time period in the first correspondence, or matches the first time period with the preset first time period corresponding to the first position change amount in the first correspondence, and the obtaining unit 1110 determines the position of the first device by the obtained voltage value, the first voltage value is not equal to the second voltage value.

[0175] In some possible embodiments, when the acquisition unit 1110 determines the position of the first device by acquiring the voltage value, and the first voltage value and the second voltage value are equal to the first fixed voltage value, the determination unit 1120 is further specifically used to: determine a second time period in which the voltage value of the first device is maintained at the first fixed voltage value when the motor is running normally; if the first time period is longer than the second time period, determine that the motor is stalled; or, if the first time period is shorter than or equal to the second time period, determine that the motor is running normally.

[0176] In some possible embodiments, the above-described device 1100 further includes:

[0177] The control unit 1130 is used to control the motor to stop operating when the number of times the motor malfunctions reaches N within a preset time period, where N is a preset value, N is a positive integer, and the preset time period is greater than or equal to the duration of the first time period.

[0178] In some possible embodiments, this application also proposes an apparatus for detecting motor faults, the apparatus including a processor and a memory, wherein the processor and the memory are connected, the memory is used to store program code, and the processor is used to call the program code to execute any of the methods for detecting motor faults proposed in this application.

[0179] Furthermore, embodiments of this application also propose a controller, which includes any of the motor fault detection devices proposed in embodiments of this application.

[0180] In some possible embodiments, the controller described above is applied to a vehicle, and the first device proposed in this application embodiment is a rearview mirror of the vehicle. Additionally, the rearview mirror includes a sliding rheostat, the resistance of which is associated with the position to which the rearview mirror is moved.

[0181] In some possible embodiments, the aforementioned motor, controller, and sliding rheostat can all be integrated into the housing of the rearview mirror.

[0182] Furthermore, this application also proposes a vehicle that includes any of the motor fault detection devices or controllers proposed in this application.

[0183] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0184] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0185] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0186] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0187] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0188] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application.

[0189] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method of detecting a fault in an electric machine, characterized by, The method includes: The system acquires a first time period, a first position of a first device at the start of the first time period, and a second position of a first device at the end of the first time period, wherein the first device is driven by the motor. Based on the first position and the second position, determine the change in the first position; Based on the first time period, the first position change, and the first correspondence, it is determined whether the motor has malfunctioned. The first correspondence is used to indicate a preset correspondence between the first position change and the first time period.

2. The method of claim 1, wherein, The step of determining whether the motor has malfunctioned based on the first time period, the first position change, and the first correspondence includes: The first position change is matched with the preset first position change corresponding to the first time period in the first correspondence. If the first position change does not match the preset first position change, the motor is determined to be faulty; or, if the first position change matches the preset first position change, the motor is determined to be operating normally.

3. The method of claim 2, wherein, Determining that the motor has malfunctioned when the first position change does not match the preset first position change includes: If the change in the first position is less than the preset change in the first position, and the difference between the preset change in the first position and the change in the first position is greater than the preset first threshold, the fault of the motor is determined to be motor stall or motor clutch disengagement. Alternatively, if the change in the first position is greater than the preset change in the first position, and the difference between the first change in the first position and the change in the first position is greater than the preset first threshold, the fault of the motor is determined to be motor gear breakage.

4. The method of claim 1, wherein, The step of determining whether the motor has malfunctioned based on the first time period, the first position change, and the first correspondence includes: The first time period is matched with the preset first time period corresponding to the first position change in the first correspondence. If the first time period does not match the preset first time period, the motor is determined to be faulty; or, if the first time period matches the preset first time period, the motor is determined to be operating normally.

5. The method of claim 4, wherein, In cases where the first time period does not match the preset first time period, determining that the motor has malfunctioned includes: If the first time period is longer than the preset first time period and the difference between the first time period and the preset first time period is greater than a preset second threshold, the fault of the motor is determined to be motor stall or motor clutch disengagement; or, if the first time period is shorter than the preset first time period and the difference between the preset first time period and the first time period is greater than a preset second threshold, the fault of the motor is determined to be motor gear breakage.

6. The method according to any one of claims 2 to 5, characterized in that, The acquisition of the first time period, the first position of the first device at the start time of the first time period, and the second position at the end time of the first time period includes: Obtain the first voltage value of the first device at the start time of the first time period and the second voltage value at the end time of the first time period; Based on the first voltage value and the second voltage value, a first voltage change is determined, which is used to indicate the first position change.

7. The method of claim 6, wherein, The first voltage value is not equal to the second voltage value.

8. The method of claim 6, wherein, The first voltage value and the second voltage value are equal to the first fixed voltage value. The step of determining whether the motor has malfunctioned based on the first time period, the first position change, and the first correspondence further includes: If the voltage value of the first device remains at the first fixed voltage value for a second period when the motor is operating normally, and the first period is longer than the second period, the motor is determined to be stalled; or, if the first period is shorter than or equal to the second period, the motor is determined to be operating normally.

9. The method according to any one of claims 1 to 8, characterized in that, The method further includes: If the number of times the motor malfunctions reaches N within a preset time period, the motor is controlled to stop operating. N is a preset value, which is a positive integer, and the preset time period is greater than or equal to the duration of the first time period.

10. An apparatus for detecting a fault in an electric machine, characterized by include: The acquisition unit is used to acquire a first time period, a first position of a first device at the start time of the first time period, and a second position of a first device at the end time of the first time period, wherein the first device is driven by the motor. A determining unit is configured to determine the change in the first position based on the first position and the second position; Based on the first time period, the first position change, and the first correspondence, it is determined whether the motor has malfunctioned. The first correspondence is used to indicate a preset correspondence between the first position change and the first time period.

11. The apparatus of claim 10, wherein, The determining unit is specifically used for: The first position change is matched with the preset first position change corresponding to the first time period in the first correspondence. If the first position change does not match the preset first position change, the motor is determined to be faulty; or, if the first position change matches the preset first position change, the motor is determined to be operating normally.

12. The apparatus of claim 11, wherein, The determining unit is specifically used for: If the change in the first position is less than the preset change in the first position, and the difference between the preset change in the first position and the change in the first position is greater than the preset first threshold, the fault of the motor is determined to be motor stall or motor clutch disengagement. Alternatively, if the change in the first position is greater than the preset change in the first position, and the difference between the first change in the first position and the change in the first position is greater than the preset first threshold, the fault of the motor is determined to be motor gear breakage.

13. The apparatus according to claim 10, characterized in that, The determining unit is specifically used for: The first time period is matched with the preset first time period corresponding to the first position change in the first correspondence. If the first time period does not match the preset first time period, the motor is determined to be faulty; or, if the first time period matches the preset first time period, the motor is determined to be operating normally.

14. The apparatus according to claim 13, characterized in that, The determining unit is specifically used for: If the first time period is longer than the preset first time period and the difference between the first time period and the preset first time period is greater than a preset second threshold, the fault of the motor is determined to be motor stall or motor clutch disengagement; or, if the first time period is shorter than the preset first time period and the difference between the preset first time period and the first time period is greater than a preset second threshold, the fault of the motor is determined to be motor gear breakage.

15. The apparatus according to any one of claims 11 to 14, characterized in that, The acquisition unit is specifically used for: Obtain the first voltage value of the first device at the start time of the first time period and the second voltage value at the end time of the first time period; Based on the first voltage value and the second voltage value, a first voltage change is determined, which is used to indicate the first position change.

16. The apparatus according to claim 15, characterized in that, The first voltage value is not equal to the second voltage value.

17. The apparatus according to claim 15, characterized in that, The first voltage value and the second voltage value are equal to a first fixed voltage value, and the determining unit is further specifically used for: If the voltage value of the first device remains at the first fixed voltage value for a second period when the motor is operating normally, and the first period is longer than the second period, the motor is determined to be stalled; or, if the first period is shorter than or equal to the second period, the motor is determined to be operating normally.

18. The apparatus according to any one of claims 10 to 17, characterized in that, The device further includes: The control unit is configured to control the motor to stop operating when the number of times the motor malfunctions reaches N within a preset time period, where N is a preset value, N is a positive integer, and the preset time period is greater than or equal to the duration of the first time period.

19. A device for detecting motor faults, characterized in that, It includes a processor and a memory, wherein the processor and the memory are connected, wherein the memory is used to store program code, and the processor is used to call the program code to perform the method as described in any one of claims 1 to 9.

20. A controller, characterized in that, Includes the apparatus as described in any one of claims 10 to 19.

21. The controller according to claim 20, characterized in that, The controller is applied to a vehicle, and the first device is the vehicle's rearview mirror.

22. The controller according to claim 21, characterized in that, The rearview mirror includes a sliding rheostat, the resistance of which is associated with the position to which the rearview mirror is moved.

23. A vehicle, characterized in that, It includes the device as described in any one of claims 10 to 19, or the controller as described in any one of claims 20 to 22.

24. A chip system, characterized in that, The chip system is applied to an electronic device; the chip system includes one or more interface circuits and one or more processors; the interface circuits and the processors are interconnected via lines; the interface circuits are used to receive signals from the memory of the electronic device and send the signals to the processors, the signals including computer instructions stored in the memory; when the processor executes the computer instructions, the electronic device performs the method as described in any one of claims 1 to 9.

25. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that is executed by a processor to implement the method as described in any one of claims 1 to 9.

26. A computer program product, characterized in that, It includes instructions that, when executed by a processor, cause the method of any one of claims 1 to 9 to be performed.

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