Motor open-phase fault detection method, water pump and automobile
By obtaining the maximum and minimum absolute values of the three-phase current of the motor to calculate the current imbalance characteristic value, the accuracy and timeliness problems of motor phase loss fault detection in the existing technology are solved, and real-time and accurate detection is realized in a variety of scenarios.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-25
- Publication Date
- 2026-03-27
AI Technical Summary
Existing methods for detecting phase loss faults in motors have poor accuracy in single-sampling resistor scenarios and poor timeliness in scenarios with limited hardware data storage capacity.
By obtaining the absolute values of the maximum and minimum three-phase currents of the target motor at the same moment, the characteristic values of the current imbalance feature are calculated, and the characteristic values of the current imbalance feature are used to determine whether the motor has a phase loss fault.
It enables real-time and accurate detection of motor phase loss faults in various scenarios, and is suitable for scenarios with single sampling resistors and limited hardware data storage capabilities.
Smart Images
Figure CN121741471A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of motor control, in particular to a motor open-phase fault detection method, a water pump and an automobile. BACKGROUND
[0002] The open-phase fault of a motor is one of the common faults in the operation process of the motor. At present, the following two ways are usually used to detect the open-phase fault of the motor:
[0003] One way is based on the principle that the phase current of the open-phase is zero. Whether the motor has an open-phase fault is determined by detecting whether the current value of a certain phase current is continuously less than a set current threshold. However, this way is not applicable to the scene of single sampling resistance. Because in the scene of single sampling resistance, the current threshold is difficult to set accurately due to the open-phase current being easily reconstructed by mistake, thereby affecting the accuracy of open-phase fault detection.
[0004] Another way is based on the principle of three-phase imbalance. Whether the motor has an open-phase fault is determined by detecting whether the maximum value of the average value of each phase current in a certain period is greater than a set current threshold. However, this way needs to obtain and process current data at multiple time points to complete the open-phase fault detection of the motor, so the detection timeliness of this way is poor, and the requirement for hardware data storage capacity is also high, which is not suitable for scenes with poor hardware data storage capacity. SUMMARY
[0005] The main purpose of the present application is to provide a motor open-phase fault detection method, a water pump and an automobile, aiming to provide a motor open-phase fault detection mechanism with good timeliness, wide applicability and high detection accuracy, so as to ensure real-time and accurate detection of the open-phase fault of the motor in various scenes.
[0006] To achieve the above-mentioned purpose, the present application provides a motor open-phase fault detection method, which comprises:
[0007] obtaining the maximum current absolute value and the minimum current absolute value in the absolute values of the three-phase currents of a target motor at the same time;
[0008] determining a target feature value of a current imbalance feature of the target motor according to the maximum current absolute value and the current difference between the maximum current absolute value and the minimum current absolute value; the current imbalance feature is used to represent the offset amount of the amplitude difference of the three-phase currents of the motor relative to the amplitude difference in the current balanced state, and the magnitude of the offset amount is negatively related to the feature value of the current imbalance feature;
[0009] if the target feature value is less than a preset feature threshold, it is determined that the target motor has an open-phase fault.
[0010] In an embodiment, the step of determining the target feature value of the current imbalance feature of the target motor according to the maximum current absolute value and the current difference between the maximum current absolute value and the minimum current absolute value comprises:
[0011] calculating a ratio of the current difference and the maximum current absolute value to obtain a target value of the offset;
[0012] performing inverse processing on the target value of the offset to obtain an initial feature value of the current imbalance feature of the target motor;
[0013] determining the target feature value of the current imbalance feature of the target motor according to the initial feature value.
[0014] In an embodiment, the step of determining the target feature value of the current imbalance feature of the target motor according to the initial feature value comprises:
[0015] performing filtering processing on the initial feature value to obtain the target feature value.
[0016] In an embodiment, the step of determining the target feature value of the current imbalance feature of the target motor according to the maximum current absolute value and the current difference between the maximum current absolute value and the minimum current absolute value comprises:
[0017] obtaining, according to a preset mapping relationship between a current absolute value, a current difference and a feature value of a current imbalance feature, a feature value of a current imbalance feature corresponding to the maximum current absolute value and the current difference together as the target feature value of the current imbalance feature of the target motor.
[0018] In an embodiment, before the step of obtaining the maximum current absolute value and the minimum current absolute value in the current absolute values of each phase of the three-phase current of the target motor at the same time, the method further comprises:
[0019] monitoring whether the target motor enters a closed-loop running state after the target motor is started;
[0020] if yes, performing the step of obtaining the maximum current absolute value and the minimum current absolute value in the current absolute values of each phase of the three-phase current of the target motor at the same time.
[0021] In an embodiment, the step of monitoring whether the target motor enters a closed-loop running state comprises:
[0022] obtaining a starting duration of the target motor;
[0023] if the starting duration is greater than a preset starting duration threshold, determining that the target motor enters a closed-loop running state.
[0024] In an embodiment, after the step of determining that the target motor has an open-phase fault, the method further comprises:
[0025] controlling the target motor to stop and outputting an open-phase fault alarm prompt information.
[0026] In an embodiment, after controlling the target motor to stop, the method further comprises:
[0027] acquiring a cumulative stop number of the target motor in a preset period;
[0028] if the cumulative stop number is less than or equal to a preset number threshold, restarting the target motor after the target motor stops for a preset duration.
[0029] In addition, to achieve the above object, the present application also provides a water pump, comprising a controller and a motor connected in sequence; the controller is used to execute the steps of the motor open-phase fault detection method as described above.
[0030] In addition, to achieve the above object, the present application also provides an automobile, comprising a water pump, which is used to execute the steps of the motor open-phase fault detection method as described above.
[0031] In addition, to achieve the above object, the present application also provides a computer readable storage medium, wherein the computer readable storage medium stores a computer program, and the computer program is executed by a processor to implement the steps of the motor open-phase fault detection method as described above.
[0032] In addition, to achieve the above object, the present application also provides a computer program product, comprising a computer program, and the computer program is executed by a processor to implement the steps of the motor open-phase fault detection method as described above.
[0033] The application provides a motor open-phase fault detection method. First, the maximum current absolute value and the minimum current absolute value of each phase current absolute value of three-phase currents of a target motor at the same time are obtained. Then, according to the maximum current absolute value and the current difference between the maximum current absolute value and the minimum current absolute value, a target feature value of a current imbalance feature of the target motor is determined. The current imbalance feature is used to represent the offset of the amplitude difference of the three-phase currents of the motor relative to the amplitude difference in the current balance state. The magnitude of the offset is negatively correlated with the feature value of the current imbalance feature. When the motor has an open-phase fault, the three-phase currents of the motor will be unbalanced, so the offset of the amplitude difference of the three-phase currents of the motor relative to the amplitude difference in the current balance state will increase, and thus the feature value of the current imbalance feature will decrease. Therefore, if the target feature value of the current imbalance feature is less than a preset feature threshold, it indicates that the offset of the amplitude difference of the three-phase currents of the target motor relative to the amplitude difference in the current balance state is large, and the three-phase currents of the target motor are unbalanced. Thus, it can be determined that the target motor has an open-phase fault.
[0034] Therefore, the application provides a method for detecting the open-phase fault of the motor by using the feature value of the current imbalance feature. Since only the current data at one time is needed to calculate the feature value, the timeliness of the detection is good, and it is not necessary to record the current sampling data for a period of time, and the requirement for the hardware data storage capacity is also low. Moreover, when the three-phase currents of the motor are balanced, the feature value of the current imbalance feature is basically stable around a certain value, so the setting of the preset feature threshold will not become difficult to accurately set due to the error reconstruction of the current or the change of the motor load working condition. Therefore, it can be known that the application is not only suitable for the scene of multiple sampling resistors, but also suitable for the scene of single sampling resistors, and has strong adaptability to different load working conditions.
[0035] Therefore, as can be known from the above, the motor open-phase fault detection method provided by the application can realize real-time and accurate detection of the open-phase fault of the motor in various scenes. BRIEF DESCRIPTION OF DRAWINGS
[0036] The accompanying drawings, which are incorporated into and form part of the specification, illustrate embodiments consistent with the application and, together with the specification, serve to explain the principles of the application.
[0037] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the accompanying drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, those skilled in the art can obtain other drawings from these drawings without any creative effort.
[0038] Figure 1 A flowchart of the motor open-phase fault detection method provided by the first embodiment of the application is shown.
[0039] Figure 2 A waveform diagram of each phase current of the motor before and after a fault is provided for an embodiment of the present application;
[0040] Figure 3 A schematic diagram of the change in the characteristic value of the current imbalance feature when a phase failure of the motor occurs and disappears is provided for an embodiment of the present application;
[0041] Figure 4 A whole implementation flowchart of the motor phase failure detection method is provided for an embodiment of the present application;
[0042] Figure 5 A module structure schematic diagram of the water pump is provided for an embodiment of the present application.
[0043] The purposes, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION
[0044] It should be understood that the specific embodiments described herein are merely intended to explain the technical solutions of the present application, and are not intended to limit the present application.
[0045] In order to better understand the technical solutions of the present application, the specific embodiments will be described in detail below with reference to the drawings and the specific embodiments.
[0046] The automobile water pump actuator usually selects a permanent magnet synchronous motor, because it has high control accuracy, can realize more accurate speed and torque control, and can also realize lower noise and vibration advantages. Under complex automobile operating conditions, power overload fusing, winding wire virtual welding, poor contact of power supply circuit switch or contactor, and the like may cause a phase failure of the motor. Under the phase failure, the motor may still maintain "normal" operation for a period of time without obvious characteristics. After a certain period of accumulation, the overhigh temperature rise and gradually increasing noise caused by the phase failure will affect the driving safety. Therefore, in order to avoid the risks caused by the phase failure of the motor, the following two methods are usually used to detect the phase failure of the motor at present:
[0047] One way is based on the principle that the phase current of the phase failure is zero, and whether the motor has a phase failure is determined by detecting whether the current value of a certain phase current is continuously less than a set current threshold. However, this way is not suitable for the single sampling resistor scenario. Because in the single sampling resistor scenario, the phase failure current is easily reconstructed by mistake, and it is difficult to set the current threshold accurately, thereby affecting the accuracy of the phase failure detection.
[0048] Another approach is based on the principle of three-phase imbalance. It determines whether a motor has a phase loss fault by detecting whether the maximum value of the average current of each phase over a certain period is greater than a set current threshold. However, this method requires acquiring and processing current data at multiple points in time to complete the phase loss fault detection. Therefore, this method has poor detection timeliness and high requirements for hardware data storage capacity, making it unsuitable for scenarios with poor hardware data storage capacity.
[0049] Based on this, this application provides a method for detecting phase loss faults in motors. First, the maximum and minimum absolute values of the three-phase currents of the target motor at the same moment are obtained. Then, based on the maximum absolute value of the current and the current difference between the maximum and minimum absolute values, a target characteristic value for the current imbalance feature of the target motor is determined. The current imbalance feature characterizes the deviation of the amplitude difference of the three-phase currents relative to the amplitude difference in the current balanced state. The magnitude of the deviation is negatively correlated with the characteristic value of the current imbalance feature. Since the three-phase currents of the motor become unbalanced when a phase loss fault occurs, the deviation of the amplitude difference of the three-phase currents relative to the amplitude difference in the current balanced state will increase, thus decreasing the characteristic value of the current imbalance feature. Therefore, if the determined target characteristic value of the current imbalance feature is less than a preset characteristic threshold, it indicates that the deviation of the amplitude difference of the three-phase currents of the target motor relative to the amplitude difference in the current balanced state is large, indicating an imbalance in the three-phase currents of the target motor. Thus, it can be determined that the target motor has a phase loss fault.
[0050] Therefore, this application provides a method for detecting phase loss faults in motors by utilizing the characteristic values of current imbalance features. Since the characteristic value can be calculated using only the current data at a single moment, it offers good timeliness and eliminates the need to record current sampling data over a period of time, thus reducing the requirements for hardware data storage capacity. Furthermore, because the characteristic value of the current imbalance feature is basically stable around a certain value when the three-phase current of the motor is balanced, the setting of the preset characteristic threshold will not become difficult to accurately set due to current erroneous reconstruction or changes in motor load conditions. Therefore, this application is applicable not only to scenarios with multiple sampling resistors but also to scenarios with single sampling resistors, and has strong adaptability to different load conditions.
[0051] Therefore, as can be seen from the above, the motor phase loss fault detection method provided in this application can achieve real-time and accurate detection of motor phase loss faults in various scenarios.
[0052] The subject of the motor phase loss fault detection method of this application can be a water pump containing a motor, or a control device or control circuit that can realize data processing, network communication and program operation functions. This embodiment does not specifically limit it.
[0053] The following describes each embodiment below with a water pump as an execution subject.
[0054] Based on this, the motor open-phase fault detection method of the first embodiment is proposed, please refer to Figure 1 The motor open-phase fault detection method includes steps S10-S30:
[0055] Step S10, obtaining the maximum current absolute value and the minimum current absolute value in the absolute values of the three-phase currents of the target motor at the same time;
[0056] It should be noted that the target motor refers to the motor that needs to be detected for open-phase fault, and the number of target motors can be one or multiple, which is not limited in the embodiment. The three-phase current of the target motor refers to the current of the U phase, V phase, W phase / A phase, B phase and C phase of the target motor.
[0057] In addition, it should be noted that when obtaining the maximum current absolute value and the minimum current absolute value in the absolute values of the three-phase currents of the target motor at the same time, the current sampling module can be used to obtain the current values of the three-phase currents of the target motor at the same time, and then the absolute value function is used to mathematically process the obtained current values, so that the absolute values of the three-phase currents of the target motor at the same time are obtained. Then, the maximum value and the minimum value of the obtained absolute values of the three-phase currents are determined, so that the maximum current absolute value and the minimum current absolute value in the absolute values of the three-phase currents of the target motor at the same time are obtained.
[0058] The process of mathematically processing the obtained current values by using the absolute value function can be represented by the following formula 1:
[0059]
[0060] Wherein, k represents the k time, I u , I v , I w represent the current values of each phase of the motor, abs() is the absolute value function, ABSI u , ABSI v , ABSI w represent the absolute values of the current of each phase of the motor.
[0061] Based on formula 1, the implementation process of step S10 can be represented by the following formula 2:
[0062]
[0063] Wherein, ABSI maxABSI is the maximum current absolute value min ABSM is the minimum current absolute value.
[0064] Additionally, the current sampling module can be composed of one or more sampling resistors. When the current sampling module includes multiple sampling resistors, the current values of each phase of the three-phase current of the target motor at the same time can be directly collected by the sampling resistors. When the current sampling module includes only one sampling resistor, the current values of two phases of the target motor can be collected by the sampling resistor first, and then the current value of the remaining one phase (i.e., the reconstruction operation of the missing phase current) can be calculated by using the balance principle of the three-phase current (i.e., the sum of the three-phase currents is zero).
[0065] In step S20, a target feature value of the current imbalance feature of the target motor is determined according to the maximum current absolute value and the current difference between the maximum current absolute value and the minimum current absolute value. The current imbalance feature is used to represent the offset of the amplitude difference of the three-phase current of the motor relative to the amplitude difference in the current balance state, and the magnitude of the offset is negatively related to the feature value of the current imbalance feature.
[0066] It should be noted that the amplitudes of the three-phase current of the motor in the current balance state are equal to each other, i.e., the amplitude difference is zero. When the three-phase current of the motor is unbalanced, the offset of the amplitude difference of the three-phase current of the motor relative to the amplitude difference in the current balance state is large, and the feature value of the current imbalance feature decreases. When the three-phase current of the motor is balanced, the offset of the amplitude difference of the three-phase current of the motor relative to the amplitude difference in the current balance state is small, and the feature value of the current imbalance feature is basically stable around a certain value. The target feature value refers to the feature value of the current imbalance feature of the target motor at the current time.
[0067] In step S30, if the target feature value is less than a preset feature threshold, it is determined that the target motor has a missing phase fault.
[0068] It should be noted that the preset feature threshold is used as a basis for judging whether the three-phase current of the motor is balanced. The preset feature threshold can be a default value, or can be flexibly set by the user according to the actual situation, and the present embodiment does not make a specific limitation thereto.
[0069] It can be understood that when the motor does not have a missing phase fault, the three-phase current of the motor will be in a balanced state. When the motor has a missing phase fault, the three-phase current of the motor will be unbalanced, the offset of the amplitude difference of the three-phase current of the motor relative to the amplitude difference in the current balance state is large, and the feature value of the current imbalance feature will decrease. Therefore, by using the actual feature value of the current imbalance feature of the motor, it can be accurately determined whether the motor has a missing phase fault.
[0070] The embodiment provides a motor open-phase fault detection method. First, maximum current absolute value and minimum current absolute value in each-phase current absolute value of three-phase currents of a target motor at the same time are acquired. Then, a target feature value of a current imbalance feature of the target motor is determined according to the maximum current absolute value and a current difference between the maximum current absolute value and the minimum current absolute value. The current imbalance feature is used to represent an offset amount of an amplitude difference of the three-phase currents of the motor relative to an amplitude difference in a current balance state. The offset amount is negatively related to the feature value of the current imbalance feature. When the motor has an open-phase fault, the three-phase currents of the motor are imbalanced, so the offset amount of the amplitude difference of the three-phase currents of the motor relative to the amplitude difference in the current balance state is increased, and thus the feature value of the current imbalance feature is reduced. Therefore, if the target feature value of the current imbalance feature is smaller than a preset feature threshold, it indicates that the offset amount of the amplitude difference of the three-phase currents of the target motor relative to the amplitude difference in the current balance state is large, and the three-phase currents of the target motor are imbalanced. Therefore, it can be determined that the target motor has an open-phase fault.
[0071] Therefore, the embodiment provides a method for realizing open-phase fault detection of a motor by using a feature value of a current imbalance feature. Since the feature value can be calculated by using current data at one time, the method has good timeliness, does not need to record current sampling data for a period of time, and has low requirements on hardware data storage capacity. Moreover, when the three-phase currents of the motor are balanced, the feature value of the current imbalance feature is basically stable around a value, so the preset feature threshold is not difficult to accurately set due to errors in current reconstruction or changes in motor load working conditions. Therefore, the application is suitable for scenes of single sampling resistance and has strong adaptability to different load working conditions.
[0072] Therefore, as can be seen from the above, the motor open-phase fault detection method provided by the embodiment can realize real-time and accurate detection of motor open-phase faults in various scenes.
[0073] In a feasible implementation manner, the step S20 can include steps S21-S23.
[0074] In step S21, a ratio of the current difference to the maximum current absolute value is calculated to obtain a target value of the offset amount.
[0075] It should be noted that the target value refers to the value of the offset amount at the current time. The value of the offset amount is essentially the difference between the amplitude difference of the three-phase currents of the motor and the amplitude difference in the current balance state. The amplitude difference in the current balance state is zero, and the ratio of the current difference to the maximum current absolute value represents the amplitude difference of the three-phase currents of the motor as a whole. Therefore, the ratio of the current difference to the maximum current absolute value can be directly used as the target value of the offset amount.
[0076] Step S22, the target value of the offset is processed by taking the reciprocal, and the initial characteristic value of the current imbalance characteristic of the target motor is obtained;
[0077] It should be noted that the initial characteristic value is the original value of the target characteristic value. When the target value of the offset is processed by taking the reciprocal, the reciprocal of the target value of the offset can be directly taken as the initial characteristic value of the current imbalance characteristic of the target motor. Therefore, the implementation process of step S21 and step S22 can be represented by the following formula 3:
[0078]
[0079] Wherein, I signal is the initial characteristic value.
[0080] Exemplarily, based on formula 3, in order to help understand the technical principle that the magnitude of the offset is negatively related to the characteristic value of the current imbalance characteristic, taking the example that the three-phase current of the motor is in a balanced state at 0-k1 moment (i.e. the offset of the amplitude difference of the three-phase current relative to the amplitude difference in the current balanced state is small), and is unbalanced after k1 moment (i.e. the offset of the amplitude difference of the three-phase current relative to the amplitude difference in the current balanced state is large), please refer to Figure 2 . As shown in the figure, after the three-phase current of the motor is unbalanced, the difference between the maximum current absolute value ABSImax and the minimum current absolute value ABSImin (i.e. the current difference ABSImid) will be larger, and the variation amplitude of the current difference ABSImid is larger than that of the maximum current absolute value ABSImax, i.e. the variation amplitude of the denominator of formula 3 is larger than that of the numerator, so the result output by formula 3 will be smaller.
[0081] Further, please refer to Figure 3 , Figure 3 , which shows the change of the characteristic value of the current imbalance characteristic when the open-phase fault of the motor occurs and disappears. Specifically, when the U phase of the motor has an open-phase fault, the characteristic value of the current imbalance characteristic is less than the preset characteristic threshold for the first time, and then gradually rises to a steady state as the open-phase fault disappears. After that, when the V phase of the motor has an open-phase fault, the characteristic value of the current imbalance characteristic is less than the preset characteristic threshold for the second time, and then gradually rises to a steady state as the open-phase fault disappears. After that, when the W phase of the motor has an open-phase fault, the characteristic value of the current imbalance characteristic is less than the preset characteristic threshold for the third time, and then gradually rises to a steady state as the open-phase fault disappears.
[0082] Step S23, according to the initial characteristic value, the target characteristic value of the current imbalance characteristic of the target motor is determined.
[0083] It should be noted that, when the target characteristic value of the current imbalance characteristic of the target motor is determined according to the initial characteristic value, the initial characteristic value can be directly taken as the target characteristic value of the current imbalance characteristic of the target motor; and in order to further ensure the accuracy of the subsequent motor open-phase detection, the initial characteristic value can also be filtered (for example, low-pass filtered) to remove burrs in the initial characteristic value; and then the initial characteristic value after filtering is taken as the target characteristic value. The specific implementation of step S23 is not specifically limited in this embodiment.
[0084] In another possible implementation, step S20 can include step S24:
[0085] In step S24, according to a preset mapping relationship between the current absolute value, the current difference and the characteristic value of the current imbalance characteristic, a characteristic value of the current imbalance characteristic corresponding to the maximum current absolute value and the current difference is obtained as the target characteristic value of the current imbalance characteristic of the target motor.
[0086] In this embodiment, by using the preset mapping relationship between the current absolute value, the current difference and the characteristic value of the current imbalance characteristic, the target characteristic value of the current imbalance characteristic of the target motor can be directly determined. Compared with the determination of the target characteristic value of the current imbalance characteristic of the target motor by calculation (i.e., the previous embodiment of step S20), since no additional intermediate process is involved (i.e., the target characteristic value is directly obtained, rather than the initial characteristic value is obtained first and then the target characteristic value is determined from the initial characteristic value), the determination efficiency is better.
[0087] The above are only two possible implementations of step S20 provided by this embodiment, and the specific implementation of step S20 is not specifically limited in this embodiment.
[0088] Further, in a possible implementation, a relationship table can be used to record the mapping relationship between the current absolute value, the current difference and the characteristic value of the current imbalance characteristic, so that step S24 can include: taking the maximum current absolute value and the current difference as indexes, searching in the preset relationship table to obtain a characteristic value of the current imbalance characteristic corresponding to the maximum current absolute value and the current difference as the target characteristic value of the current imbalance characteristic of the target motor.
[0089] In another possible implementation, a relationship curve can be used to record the mapping relationship between the current absolute value, the current difference and the characteristic value of the current imbalance characteristic, so that step S24 can include: inputting the maximum current absolute value and the current difference into a curve function of the preset relationship curve to obtain the target characteristic value of the current imbalance characteristic of the target motor.
[0090] It should be noted that for the above two embodiments of recording the mapping relationship between the current absolute value, the current difference and the target characteristic value of the current unbalance characteristic, although the relationship table is used for recording, the determination efficiency is good, but the amount of data recorded by the relationship table is limited, so it can only be applied to the determination of the target characteristic value of the current unbalance characteristic of part of the current absolute value and the current difference (i.e. the current absolute value and the current difference recorded in the table). Although the determination efficiency of the relationship curve is not as good as that of the relationship table, a large amount of data can be recorded, so the application range is wider, and the accuracy of the determined target characteristic value of the current unbalance characteristic can be ensured. Therefore, in actual use, the user can flexibly select the way of recording the mapping relationship between the current absolute value, the current difference and the target characteristic value of the current unbalance characteristic according to actual needs.
[0091] Based on the above first embodiment, a second embodiment of the motor open-phase fault detection method is provided. In the second embodiment, before step S10, the motor open-phase fault detection method can further include steps S01-S02:
[0092] Step S01, after the target motor is started, whether the target motor enters a closed-loop running state is monitored.
[0093] It should be noted that after the target motor is started, the target motor can be initialized to enter the closed-loop running state.
[0094] In actual use, the target motor is usually set to enter the closed-loop running state by default after starting for a certain time. Therefore, whether the target motor enters the closed-loop running state can be determined by the starting time of the target motor. On this basis, in a feasible embodiment, step S01 can include steps S011-S012:
[0095] Step S011, the starting time of the target motor is obtained.
[0096] Step S012, if the starting time is greater than a preset starting time threshold, it is determined that the target motor enters the closed-loop running state.
[0097] It should be noted that the preset starting time threshold is used as a basis for determining whether the motor enters the closed-loop running state. The preset starting time threshold can be a default value, or can be flexibly set by the user according to actual conditions, and the present embodiment does not make specific limitations.
[0098] In another possible implementation, step S01 can include: acquiring the actual rotating speed and the actual angle of the target motor by a position sensorless; and determining that the target motor enters the closed-loop operation state if the actual rotating speed is the same as the target rotating speed and the actual angle is the same as the target angle. The target rotating speed is a rotating speed value that the target motor should reach when in the closed-loop operation state, and the target angle is an angle value that the target motor should reach when in the closed-loop operation state.
[0099] The above are only two possible implementations of step S01 provided by this embodiment, and this embodiment does not specifically limit the specific implementation of step S01.
[0100] Step S02, if yes, performing a step of acquiring the maximum current absolute value and the minimum current absolute value in the absolute values of the three-phase currents of the target motor at the same time.
[0101] According to the above implementation, after the target motor is started, the subsequent detection of the open-phase fault of the target motor is performed after the target motor enters the closed-loop operation state, that is, after it is ensured that the currents of the target motor have become stable. Therefore, the detection accuracy of the open-phase fault of the motor can be further improved.
[0102] Based on the first embodiment and / or the second embodiment, a third embodiment of the motor open-phase fault detection method is provided. After step S30, the motor open-phase fault detection method can further include step S40.
[0103] Step S40: controlling the target motor to stop and outputting an open-phase fault alarm prompt information.
[0104] It should be noted that the open-phase fault alarm prompt information is used to remind the user that the target motor has an open-phase fault.
[0105] It can be understood that, after it is determined that the target motor has an open-phase fault, if the target motor continues to operate, it will cause a safety hazard of the equipment (such as a car) using the target motor. Therefore, according to the above implementation, after it is determined that the target motor has an open-phase fault, the target motor is controlled to stop, so as to improve the safety of the equipment using the target motor. At the same time, the water pump also outputs the open-phase fault alarm prompt information to inform the user that the target motor has an open-phase fault.
[0106] Based on the third embodiment, a fourth embodiment of the motor open-phase fault detection method is provided. After step S40, the motor open-phase fault detection method can further include steps S50-S60.
[0107] Step S50: acquiring the cumulative number of times of stopping of the target motor in a preset period.
[0108] It should be noted that the preset period can be the time interval between the starting moment of the motor and the current moment, or a default period, for example, 5 min, which is not specifically limited in the embodiment.
[0109] In step S60, if the accumulated number of stop times is less than or equal to the preset number threshold, the target motor is restarted after the target motor is stopped for a preset time length.
[0110] It should be noted that the preset number threshold is used as a basis for determining whether the target motor needs to be restarted. The preset number threshold can be a default value, for example, 3 times, or can be flexibly set by the user according to the actual situation, which is not specifically limited in the embodiment. The preset time length can be a default time length, for example, 3 s, or can be flexibly set by the user according to the actual situation, which is not specifically limited in the embodiment.
[0111] In the embodiment, if the accumulated number of stop times of the target motor within the preset period is less than or equal to the preset number threshold, the target motor can be restarted after the target motor is stopped for a preset time length. Thus, the situation that the motor is stopped for a long time due to the misjudgment of the open-phase fault can be avoided. Moreover, the technical defect that the motor is directly controlled to be stopped for a long time based on only a small number of open-phase detection results, thereby bringing a poor user experience, can be overcome, thereby improving the user experience of the equipment using the motor.
[0112] For example, to facilitate understanding of the implementation process of the motor open-phase fault detection method obtained by combining the above embodiments, please refer to Figure 4 , specifically:
[0113] After the target motor is started, it is first determined whether the target motor enters a closed-loop running state. If yes, the current sampling module is used to obtain the absolute values of the three-phase currents of the target motor at the same time. Then, the maximum current absolute value and the minimum current absolute value among the absolute values of the three-phase currents are obtained. Next, the difference between the maximum current absolute value and the minimum current absolute value is calculated to obtain a current difference. Then, the ratio of the maximum current absolute value to the current difference is calculated to obtain an initial characteristic value of the current imbalance characteristic of the target motor. Next, the initial characteristic value is filtered to obtain a target characteristic value of the current imbalance characteristic. After that, the target characteristic value is compared with a preset characteristic threshold. If the target characteristic value is less than the preset characteristic threshold, it is determined that the target motor has an open-phase fault.
[0114] It should be noted that the example is only used to assist in understanding the present application and does not constitute a limitation on the motor open-phase fault detection method of the present application. More simple transformations based on this technical concept are within the scope of protection of the present application.
[0115] The embodiment of the present application further provides a water pump, please refer to Figure 5 The water pump comprises a controller 10 and a motor 20 connected in sequence; the controller 10 is used for executing the steps of the motor open-phase fault detection method in the above-mentioned embodiments.
[0116] The water pump provided by the embodiment of the present application adopts the motor open-phase fault detection method in the above-mentioned embodiments, and proposes a detection mechanism for motor open-phase fault with good timeliness, wide application range and high detection accuracy, so as to ensure that the real-time and accurate detection of the motor open-phase fault can be realized in various scenarios. Compared with the prior art, the water pump provided by the embodiment of the present application has the same beneficial effects as the motor open-phase fault detection method provided by the above-mentioned embodiments, and other technical features in the water pump are the same as the features disclosed in the above-mentioned embodiment method, which will not be repeated here.
[0117] The embodiment of the present application further provides an automobile, the automobile comprising a water pump, which is used for executing the steps of the motor open-phase fault detection method in the above-mentioned embodiments.
[0118] The automobile provided by the embodiment of the present application adopts the motor open-phase fault detection method in the above-mentioned embodiments, and proposes a detection mechanism for motor open-phase fault with good timeliness, wide application range and high detection accuracy, so as to ensure that the real-time and accurate detection of the motor open-phase fault can be realized in various scenarios. Compared with the prior art, the automobile provided by the embodiment of the present application has the same beneficial effects as the motor open-phase fault detection method provided by the above-mentioned embodiments, and other technical features in the automobile are the same as the features disclosed in the above-mentioned embodiment method, which will not be repeated here.
[0119] The embodiment of the present application further provides a computer readable storage medium, which stores a computer program capable of running on a processor, and the computer program is used for executing the steps of the motor open-phase fault detection method in the above-mentioned embodiments.
[0120] The computer readable storage medium provided by the embodiments of the present application may, for example, be a U disk, but is not limited to an electric, magnetic, optical, electromagnetic, infrared, or semiconductor system or device, or any combination thereof. More specific examples of the computer readable storage medium may include, but are not limited to, an electric connection with one or more conductive wires, a portable computer disk, a hard disk, a random access memory (RAM), a read only memory (ROM), an erasable programmable read only memory (EPROM or flash memory), an optical fiber, a portable compact disk read only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In the embodiments, the computer readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, a system, or a device. The program code contained on the computer readable storage medium can be transmitted by any suitable medium, including but not limited to an electric wire, an optical cable, an RF (Radio Frequency), and the like, or any suitable combination thereof.
[0121] The computer readable storage medium described above may be contained in the water pump, or may exist separately and not be assembled into the water pump.
[0122] The computer readable storage medium described above carries one or more programs, when the one or more programs are executed by the water pump, the water pump: obtains a maximum current absolute value and a minimum current absolute value in each phase current absolute value of three-phase currents of a target motor at the same time; determines a target feature value of a current imbalance feature of the target motor according to the maximum current absolute value and a current difference between the maximum current absolute value and the minimum current absolute value; the current imbalance feature is used to represent an offset amount of an amplitude difference of the three-phase currents of the motor relative to an amplitude difference in a current balanced state, and a magnitude of the offset amount is negatively related to the feature value of the current imbalance feature; and if the target feature value is less than a preset feature threshold, it is determined that the target motor has an open-phase fault.
[0123] Computer program code for carrying out operations of the present disclosure can be written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like, and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computer (for example, through the Internet using an Internet Service Provider).
[0124] The flow diagrams and the block diagrams in the drawings are illustrations of architectures, functionalities, and operations of possible implementations of systems, methods, and computer program products according to various embodiments of the present application. In this regard, each block in the flow diagrams or block diagrams can represent a module, a segment, or a portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that in some alternative implementations, the functions noted in the blocks can occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently or the blocks may
[0125] The modules involved in the embodiments of the present application can be implemented in the form of software or in the form of hardware. In some cases, the name of the module does not constitute a limitation on the module itself.
[0126] The computer readable storage medium provided by the embodiments of the present application stores computer readable program instructions for executing the motor open-phase fault detection method, and proposes a motor open-phase fault detection mechanism with good timeliness, wide application range and high detection accuracy, so as to ensure that the real-time and accurate detection of the motor open-phase fault can be realized in various scenarios. Compared with the prior art, the computer readable storage medium provided by the embodiments of the present application has the same beneficial effects as the motor open-phase fault detection method provided by the above embodiments, and will not be described here.
[0127] The embodiment of the present application further provides a computer program product comprising a computer program, which, when executed by a processor, implements the steps of the motor open-phase fault detection method in the above-mentioned embodiments.
[0128] The computer program product provided by the embodiment of the present application proposes a motor open-phase fault detection mechanism with good timeliness, wide application range and high detection accuracy, so as to ensure that the real-time and accurate detection of the motor open-phase fault can be realized in various scenarios. Compared with the prior art, the beneficial effects of the computer program product provided by the embodiment of the present application are the same as those of the motor open-phase fault detection method provided by the above-mentioned embodiments, and will not be repeated here.
[0129] The above is only the preferred embodiment of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent flow transformation using the content of the specification and drawings of the present application, or direct or indirect application in other related technical fields, is also included in the patent processing scope of the present application.
Claims
1. A method for detecting a phase loss fault in a motor, characterized in that, The method includes: Obtain the maximum and minimum absolute values of the three-phase currents of the target motor at the same time. Based on the absolute value of the maximum current and the current difference between the absolute value of the maximum current and the absolute value of the minimum current, the target characteristic value of the current imbalance feature of the target motor is determined; the current imbalance feature is used to characterize the offset of the amplitude difference of the three-phase current of the motor relative to the amplitude difference in the current balance state, and the magnitude of the offset is negatively correlated with the characteristic value of the current imbalance feature. If the target feature value is less than the preset feature threshold, it is determined that the target motor has a phase loss fault.
2. The motor phase loss fault detection method as described in claim 1, characterized in that, The step of determining the target characteristic value of the current imbalance characteristic of the target motor based on the absolute value of the maximum current and the current difference between the absolute value of the maximum current and the absolute value of the minimum current includes: Calculate the ratio of the current difference to the absolute value of the maximum current to obtain the target value of the offset; The target value of the offset is reciprocalized to obtain the initial characteristic value of the current imbalance characteristic of the target motor. Based on the initial characteristic value, the target characteristic value of the current imbalance characteristic of the target motor is determined.
3. The motor phase loss fault detection method as described in claim 2, characterized in that, The step of determining the target characteristic value of the current imbalance characteristic of the target motor based on the initial characteristic value includes: The initial feature values are filtered to obtain the target feature values.
4. The motor phase loss fault detection method as described in claim 1, characterized in that, The step of determining the target characteristic value of the current imbalance characteristic of the target motor based on the absolute value of the maximum current and the current difference between the absolute value of the maximum current and the absolute value of the minimum current includes: Based on the preset mapping relationship between the absolute value of current, the current difference, and the characteristic value of current imbalance, the characteristic value of current imbalance corresponding to the maximum absolute value of current and the current difference is obtained, and used as the target characteristic value of current imbalance of the target motor.
5. The method for detecting a single-phase fault in a motor as described in any one of claims 1 to 4, characterized in that, Before the step of obtaining the maximum and minimum absolute values of the three-phase currents of the target motor at the same time, the method further includes: After the target motor is started, monitor whether the target motor enters a closed-loop operation state; If so, perform the step of obtaining the maximum and minimum absolute values of the three-phase currents of the target motor at the same time.
6. The motor phase loss fault detection method as described in claim 5, characterized in that, The step of monitoring whether the target motor has entered a closed-loop operation state includes: Obtain the start-up time of the target motor; If the startup duration exceeds a preset startup duration threshold, the target motor is determined to have entered a closed-loop operation state.
7. The method for detecting a single-phase fault in a motor as described in any one of claims 1 to 4, characterized in that, After determining that the target motor has a phase loss fault, the method further includes: The target motor is controlled to stop, and a phase loss fault alarm message is output.
8. The method for detecting motor phase loss faults as described in claim 7, characterized in that, After controlling the target motor to stop, the method further includes: Obtain the cumulative number of shutdowns of the target motor within a preset period; If the cumulative number of shutdowns is less than or equal to a preset threshold, the target motor will be restarted after a preset shutdown time.
9. A water pump, characterized in that, The water pump includes a controller and a motor connected in sequence; the controller is used to perform the steps of implementing the motor phase loss fault detection method as described in any one of claims 1 to 8.
10. A car, characterized in that, The vehicle includes a water pump for performing the steps of implementing the motor phase loss fault detection method as described in any one of claims 1 to 8.