Method for detecting open phase of electric machine and related device

Abstract

The application provides a motor open-phase detection method and related equipment. The method comprises the following steps: obtaining the amplitude of the current vector of the motor, and determining whether the current is a large current or a small current according to the amplitude; for the case that the current is a large current, performing open-phase detection on the motor based on the integral of the amplitude of the current vector; for the case that the current is a small current, performing open-phase detection on the motor based on the polarity of the current. The method can distinguish between the large current and the small current according to the amplitude of the current without introducing other hardware, and then select different open-phase detection methods of the motor, thereby ensuring the accuracy and pertinence of the open-phase detection of the motor.

Description

Technical Field

[0001] This invention relates to the field of drive motor system technology, and more specifically, to a motor phase loss detection method, a motor phase loss detection device, an electronic device, and a storage medium. Background Technology

[0002] Currently, during motor operation, phase loss may occur due to problems such as damaged motor wiring harnesses, poor contact, or hardware circuit failures. If the motor remains in a phase loss state for an extended period, it will cause significant damage.

[0003] Existing phase loss diagnosis methods are mainly divided into two categories: one is detection through hardware devices, which increases hardware costs and requires high hardware reliability; the other is diagnosis through software strategies, which usually uses phase current as the analysis object. The drawback of this method is that when the phase current is small, it cannot obtain a relatively accurate current value, thus leading to misdiagnosis.

[0004] Therefore, a new technical solution is urgently needed to solve the above-mentioned technical problems. Summary of the Invention

[0005] The summary section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. The summary section of this invention is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0006] In a first aspect, the present invention proposes a method for detecting a phase loss in a motor, comprising: obtaining the magnitude of the current current vector of the motor to determine whether the current current is a large current or a small current based on the magnitude of the magnitude; for the case where the current current is a large current, performing phase loss detection on the motor based on the integral of the magnitude of the current current vector; and for the case where the current current is a small current, performing phase loss detection on the motor based on the polarity of the current current.

[0007] Optionally, the magnitude of the current current vector of the motor is obtained to determine whether the current current is a large current or a small current based on the magnitude of the magnitude. This includes: calculating the current carrier frequency ratio based on the carrier frequency and the motor's electrical frequency; setting a count during the interruption of the motor's carrier cycle to determine the sampling count step size based on the carrier frequency ratio and the count; acquiring the three-phase current of the motor when the sampling time is an integer multiple of the sampling count step size, and simultaneously acquiring the excitation current, torque current, and resolver angle; calculating the magnitude of the current current vector based on the excitation current and torque current; comparing the magnitude of the current current vector with a preset switching threshold, and determining that the current current is a small current when the magnitude is less than the preset switching threshold, and that the current current is a large current when the magnitude is greater than or equal to the preset switching threshold.

[0008] Optionally, the magnitude of the current current vector is calculated based on the excitation current and torque current, including: calculating the magnitude of the current current vector according to the following formula: ,in, This indicates the magnitude of the current vector. Indicates the excitation current. This represents torque current.

[0009] Optionally, the current carrier frequency ratio is calculated based on the carrier frequency and the electrical frequency of the motor, including: calculating the current carrier frequency ratio according to the following formula: ,in, Indicates the carrier frequency ratio. Indicates the carrier period, The electric period represents the motor's electrical cycle. The carrier period is the reciprocal of the carrier frequency, and the electrical cycle is the reciprocal of the electrical frequency. The electrical frequency is calculated based on the motor's rotational speed.

[0010] Optionally, for cases where the current current is high, a phase loss detection is performed on the motor based on the integral of the amplitude of the current current vector. This includes: taking the absolute value of the current value of any phase of the three-phase current collected from multiple points of the motor, removing the maximum value among the absolute values, and then summing the remaining absolute values ​​to obtain the current integral value of any phase of the three-phase current; comparing the current integral value with the phase loss current integral threshold to obtain a three-phase phase loss flag; and determining whether the motor has a phase loss fault based on the three-phase phase loss flag.

[0011] Optionally, for cases where the current current is low, a phase loss detection is performed on the motor based on the polarity of the current current, including: acquiring the current vector angles of the three-phase currents at multiple points of the motor to determine the polarity variables of the three-phase currents based on the current vector angles; determining the three-phase phase loss flag based on the polarity variables of the three-phase currents; and determining whether the motor has a phase loss fault based on the three-phase phase loss flag.

[0012] Optionally, determining the three-phase phase loss flag based on the polarity variable of the three-phase current includes: determining the number of times the three-phase current polarity is positive based on the polarity variable of the three-phase current; comparing the number of times with a preset number threshold to determine the three-phase phase loss flag.

[0013] Secondly, a motor phase loss detection device is proposed, comprising: a working condition differentiation module, used to obtain the magnitude of the current current vector of the motor, so as to determine whether the current current is a large current or a small current based on the magnitude of the magnitude; a large current detection module, used to detect the motor phase loss based on the integral of the magnitude of the current current vector when the current current is a large current; and a small current detection module, used to detect the motor phase loss based on the polarity of the current current when the current current is a small current.

[0014] Thirdly, an electronic device is also proposed, including a processor and a memory, wherein the memory stores computer program instructions, which are executed by the processor to perform the motor phase loss detection method described above.

[0015] Fourthly, a storage medium is also proposed, on which program instructions are stored. When the program instructions are run, they are used to execute the motor phase loss detection method described above.

[0016] The proposed method for detecting motor phase loss involves acquiring the amplitude of the motor's current current vector to determine whether the current is high or low. For high current, phase loss detection is performed based on the integral of the current current vector's amplitude. For low current, phase loss detection is performed based on the current current's polarity. This method distinguishes between high and low current conditions without introducing additional hardware, allowing for the selection of different phase loss detection methods and ensuring greater accuracy and targeted detection.

[0017] The motor phase loss detection method of the present invention, other advantages, objectives and features of the present invention will be apparent in part from the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. Attached Figure Description

[0018] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit this specification. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0019] Figure 1A schematic flowchart of a motor phase loss detection method according to an embodiment of the present invention is shown;

[0020] Figure 2 A schematic flowchart illustrating the determination of whether the current is a large current or a small current based on the magnitude of the amplitude, according to an embodiment of the present invention, is shown.

[0021] Figure 3 A schematic flowchart illustrating phase loss detection of a motor based on the integral of the magnitude of the current current vector according to an embodiment of the present invention is shown.

[0022] Figure 4 A schematic flowchart illustrating a phase loss detection of a motor based on the polarity of the current current according to an embodiment of the present invention is shown.

[0023] Figure 5 A schematic block diagram of a motor phase loss detection device according to an embodiment of the present invention is shown; and

[0024] Figure 6 A schematic block diagram of an electronic device according to an embodiment of the present invention is shown. Detailed Implementation

[0025] According to the above technical solution, by obtaining the magnitude of the current current vector of the motor, the current current can be determined as either a large current or a small current. If the current current is a large current, phase loss detection is performed on the motor based on the integral of the current current vector magnitude. If the current current is a small current, phase loss detection is performed on the motor based on the polarity of the current current. This achieves the ability to distinguish between large and small current conditions based on the magnitude of the current magnitude without introducing additional hardware, and thus select different motor phase loss detection methods, ensuring the accuracy of motor phase loss detection.

[0026] The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in a sequence other than that illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus. The technical solutions of the embodiments of this application will now be clearly and completely described in conjunction with the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them.

[0027] According to a first aspect of the present invention, the present invention provides a method for detecting a phase loss in a motor. Figure 1 A schematic flowchart of a motor phase loss detection method 100 according to an embodiment of the present invention is shown. Figure 1 As shown, method 100 may include the following steps.

[0028] Step S110: Obtain the magnitude of the current current vector of the motor to determine whether the current current is a large current or a small current based on the magnitude of the magnitude.

[0029] The magnitude of the current vector can be determined using any existing or future technology for calculating current vector magnitudes, and is not limited here. The magnitude of the current current vector of the motor is obtained to determine whether the current current is a large or small current. For example, the magnitude of the current current vector can be compared with a preset current vector magnitude; if the current current vector magnitude is greater than or equal to the preset current vector magnitude, the current current is determined to be a large current; if the current current vector magnitude is less than the preset current vector magnitude, the current current is determined to be a small current. It is understood that the preset current vector magnitude can be arbitrarily and reasonably set based on experience or specific needs, and is not limited here.

[0030] Step S120: For cases where the current current is a large current, perform phase loss detection on the motor based on the integral of the amplitude of the current current vector.

[0031] Specifically, if step S110 determines that the current is a large current, then a phase loss detection can be performed on the three-phase motor based on the integral of the amplitude of the current current vector. It can be understood that the current is a three-phase current. For example, if the amplitudes of the three-phase currents are Ia, Ib, and Ic, respectively, Ia, Ib, and Ic can be integrated. If the integral result of Ia, Ib, or Ic is less than the current integration threshold, then a phase loss is determined for phase A, phase B, or phase C of the motor. The method for calculating the integral of the current current vector amplitude is not limited here; in fact, any existing or future technical solution capable of calculating amplitude integrals is within the scope of protection of this application.

[0032] Step S130: If the current current is low, perform phase loss detection on the motor based on the polarity of the current current.

[0033] Specifically, if it is determined through step S110 that the current is a small current, then a phase loss detection can be performed on the motor based on the polarity distribution of the current. Any existing or future technology capable of detecting current polarity can be used to determine the current polarity distribution; no limitation is made here.

[0034] The proposed method for detecting motor phase loss involves acquiring the amplitude of the motor's current current vector to determine whether the current is high or low. For high current, phase loss detection is performed based on the integral of the current current vector's amplitude. For low current, phase loss detection is performed based on the current current's polarity. This method distinguishes between high and low current conditions without introducing additional hardware, allowing for the selection of different phase loss detection methods and ensuring greater accuracy and targeted detection.

[0035] It is understood that the above steps S120 and S130 are merely different implementation schemes for different situations where the current current is determined to be a large current or a small current according to step S110, and there is no order of execution in the actual execution process.

[0036] Figure 2 A schematic flowchart illustrating step S110 of the present invention is shown to obtain the magnitude of the current current vector of the motor, so as to determine whether the current current is a large current or a small current based on the magnitude of the magnitude. Figure 2 As shown, step S110 may include the following steps.

[0037] Step S111: Calculate the current carrier frequency ratio based on the carrier frequency and the motor's electrical frequency;

[0038] Alternatively, the current carrier frequency ratio can be calculated based on the carrier frequency and the electrical frequency of the motor, for example, using the following formula: ,in, Indicates the carrier frequency ratio. Indicates the carrier period, The electric period represents the motor's electrical cycle. The carrier period is the reciprocal of the carrier frequency, and the electrical cycle is the reciprocal of the electrical frequency. The electrical frequency is calculated based on the motor's rotational speed.

[0039] The above method calculates the current carrier frequency ratio by using the carrier frequency and the motor's electrical frequency, which improves the versatility of current acquisition time and the number of acquisition points over a wider electrical frequency range. This ensures that the motor phase loss can be accurately detected under different conditions, thus improving the adaptability of this method.

[0040] Step S112: Set the count during the carrier cycle interruption of the motor to determine the sampling count step size based on the carrier frequency ratio and the count;

[0041] Specifically, a count is set during a carrier cycle interruption of the motor to determine the sampling count step size based on the carrier frequency ratio and the count. The number of counts can be manually set based on experience or actual needs. For example, when the count is set to 6, ,in, This is the sampling counting step size; 6 represents the carrier frequency ratio; 6 represents the number of counts.

[0042] Step S113: When the sampling time is equal to an integer multiple of the sampling counting step, the three-phase current of the motor is collected, and the excitation current, torque current and resolver angle are obtained simultaneously.

[0043] For example, when the number of counts is manually set to 6, that is, at sampling times equal to... , , , , and During operation, the three-phase current of the motor is collected, and the excitation current, torque current, and resolver angle are simultaneously acquired. That is, in this embodiment, the three-phase current at six points can be collected. The above technical solution ensures that the collected three-phase current is uniformly distributed within one electrical cycle, and subsequent detection based on these three-phase currents can guarantee the accuracy and reliability of the detection results. It is understood that while collecting the three-phase current, it can be converted to obtain the excitation current and torque current. Those skilled in the art will understand this current conversion process, and for simplicity, it will not be described in detail here.

[0044] Step S114: Calculate the magnitude of the current vector based on the excitation current and torque current.

[0045] Any existing or future technical solutions that can calculate the magnitude based on excitation current and torque current are within the scope of protection of this application and are not limited herein.

[0046] Step S115: Compare the magnitude of the current current vector with the preset switching threshold. If the magnitude is less than the preset switching threshold, determine that the current current is a small current. If the magnitude is greater than or equal to the preset switching threshold, determine that the current current is a large current.

[0047] Specifically, preset switching threshold It can be set to 5% of the motor's rated current. For example, when the amplitude is less than 5% of the motor's rated current, that is, when the amplitude of the current vector is... <Preset switching threshold> This determines that the current is a small current; when the amplitude is greater than or equal to 5% of the motor's rated current, that is, the amplitude of the current vector... ≥Preset switching threshold This determines that the current is a high current. It is understood that the aforementioned preset switching threshold is merely an example; in reality, this preset switching threshold can be arbitrarily and reasonably set according to different situations or needs.

[0048] The proposed method for detecting motor phase loss involves calculating the current carrier frequency ratio based on the carrier frequency and the motor's electrical frequency; setting a counter during the motor's carrier cycle interruption to determine the sampling count step size based on the carrier frequency ratio and the count; acquiring the motor's three-phase current, excitation current, torque current, and resolver angle when the sampling time is an integer multiple of the sampling count step size; calculating the amplitude of the current vector based on the excitation current and torque current; comparing the amplitude of the current vector with a preset switching threshold; determining that the current current is a small current when the amplitude is less than the preset switching threshold, and a large current when the amplitude is greater than or equal to the preset switching threshold. This method correlates the current acquisition time with the motor's electrical frequency, uniformly acquiring the three-phase current values ​​and corresponding current vector values ​​at multiple points within the current cycle. This ensures that even if there are points near the zero-crossing of the phase current, the motor phase loss situation can still be determined by relying on the amplitude of the current vectors at other points not near the zero-crossing of the phase current and the polarity of the current vector current, avoiding misdiagnosis under special operating conditions and providing good compatibility across all frequency bands.

[0049] Optionally, in one specific embodiment, step S114, based on the excitation current and torque current, calculates the magnitude of the current current vector according to the following formula: ,in, This indicates the magnitude of the current vector. Indicates the excitation current. This represents torque current.

[0050] The above method calculates the magnitude of the current vector based on the excitation current and torque current, thereby distinguishing between high-current and low-current operating conditions and selecting different motor phase loss detection methods accordingly, ensuring the accuracy of motor phase loss detection. Furthermore, the above formula is simple to calculate, requires little data, and is less prone to errors, thus guaranteeing the accuracy of operating condition differentiation and providing reliable basic information and data for subsequent execution of different motor phase loss detection methods.

[0051] Figure 3 A schematic flowchart illustrating step S120 of the present invention, based on the integral of the magnitude of the current current vector, is shown to detect a phase loss in the motor when the current current is a large current. Figure 3 As shown, step S120 may include the following steps.

[0052] Step S121: After taking the absolute value of the current value of any phase of the three-phase current collected from multiple points of the motor, the maximum value of the absolute value is removed, and then the remaining absolute values ​​are summed to obtain the current integral value of any phase of the three-phase current.

[0053] Specifically, this can be achieved by removing the maximum absolute value of the current spikes. For example, when collecting current data from six points on the motor, and the absolute value of the current at the sixth point is the largest, the absolute values ​​of the currents at the remaining five points are summed. This sums the phase current integrals of phases A, B, and C. for: ,

[0054] ,

[0055] ,

[0056] in, 、 、 、 、 Phase A current at 5 sampling points ， 、 、 、 、 Phase B current at 5 sampling points ， 、 、 、 、 The C-phase current at 5 sampling points ， It can be understood that summing the absolute values ​​of the currents is equivalent to finding the integral of the magnitude of the current vector.

[0057] Step S122: Compare the current integral value with the phase loss current integral threshold to obtain the three-phase phase loss flag.

[0058] Specifically, the phase loss current integral threshold It can be set to 5% of the motor's rated current. The integral value of the current is compared with the phase loss current threshold to obtain the three-phase phase loss flag, which can then be used to... , , respectively with The comparison was conducted, and the specific details are as follows:

[0059] ,

[0060] ,

[0061] ,

[0062] in, , , This is the phase loss flag for phases A, B, and C. This is the integral threshold for the phase loss current. It should be understood that the above integral threshold for the phase loss current is merely an example, and can actually be set arbitrarily and reasonably according to different situations or specific needs.

[0063] Step S123: Based on the three-phase phase loss flag, determine whether the motor has a phase loss fault.

[0064] Specifically, when the three-phase phase loss flag is 1, it indicates that this phase is missing; conversely, 0 indicates that there is no phase loss. For example, in the integral value of phase A current... < Phase loss current integral threshold, i.e. If the fault occurs, it can be determined that phase A is faulty. Similarly, it can be determined whether other phases are faulty. For the sake of simplicity, this will not be elaborated here.

[0065] The above method obtains the integral value of the current of any phase of the three-phase current collected from multiple points of the motor by taking the absolute value of the current, removing the maximum value, and then summing the remaining absolute values. The integral value of the current is then compared with the phase loss current integral threshold to obtain the three-phase phase loss flag. Based on the three-phase phase loss flag, it is determined whether the motor has a phase loss fault. This method enables the diagnosis of phase loss by the magnitude of the current integral value when the current is large. At the same time, removing the maximum value from the sampled current value eliminates adverse interference to the diagnostic results, thereby ensuring the accuracy of the diagnosis.

[0066] Figure 4 A schematic flowchart illustrating step S130 of the present invention, based on the polarity of the current current, detects a phase loss in the motor in the case where the current current is low, according to an embodiment of the present invention. Figure 4 As shown, step S130 may include the following steps.

[0067] Step S131: Obtain the current vector angles of the three-phase currents at multiple points of the motor, so as to determine the polarity variables of the three-phase currents based on the current vector angles.

[0068] Specifically, the current vector angle Let be the sum of the angle between the d-axis and the q-axis and the angle between the d-axis and the a-axis, where The polarity variable can take the value of 0 or 1. The polarity variables of the three-phase current can be: Specifically, the polarity variables of the three-phase currents can be determined based on the following current vector angles:

[0069] exist or hour, =1, =0, =0;

[0070] exist hour, =1, =1, =0;

[0071] In 9 hour, =0, =1, =0;

[0072] exist hour, =0, =1, =1;

[0073] exist hour, =0, =0, =1;

[0074] exist hour, =1, =0, =1.

[0075] Step S132: Determine the three-phase phase loss flag based on the polarity variable of the three-phase current.

[0076] Specifically, the three-phase phase loss flag can be determined based on the polarity distribution of the three-phase current. The three-phase phase loss flags can be as follows: .

[0077] Step S133: Based on the three-phase phase loss flag, determine whether the motor has a phase loss fault.

[0078] Specifically, the three-phase loss flag bit The values ​​are either 0 or 1. For example, in the three-phase phase loss flag bit... hour ， This confirms that phase A is missing. Similarly, based on the above technical solution, it can be determined whether other phases are experiencing phase loss issues.

[0079] The above method obtains the current vector angles of the three-phase currents at multiple points in the motor, determines the polarity variables of the three-phase currents based on the current vector angles, determines the three-phase phase loss flag based on the three-phase current polarity variables, and determines whether the motor has a phase loss fault based on the three-phase phase loss flag. This method enables the acquisition of the polarity of each phase current by collecting the current vector angles when the current is small, and diagnoses whether a phase is lost by using the distribution of current polarity. This makes the polarity determination in the motor phase loss diagnosis process no longer dependent on the current magnitude, avoiding misjudgments caused by poor current sampling accuracy.

[0080] Optionally, step S133, which determines the three-phase phase loss flag based on the polarity variable of the three-phase current, may include: determining the number of times the three-phase current polarity is positive based on the polarity variable of the three-phase current; and comparing the number of times with a preset number threshold to determine the three-phase phase loss flag.

[0081] For example, when collecting the current from six points on the motor, the number of times the three-phase current polarity is positive can be determined based on the following three-phase current polarity variables: , , ;in, , , These represent the number of times the polarity of the three-phase currents A, B, and C is positive, i.e., the number of times the current is greater than 0.

[0082] ,

[0083] ,

[0084] The preset number of times threshold can be set arbitrarily and reasonably based on experience or actual situation. In this embodiment, setting the preset number of times threshold to 1 or 2 is merely exemplary and does not imply a limitation on the preset number of times threshold of this application. In fact, the preset number of times threshold can be set to any non-negative integer.

[0085] Three-phase loss flag When =1, it can be determined that phase A has a phase loss fault; When =1, it can be determined that phase B has a phase loss fault; When =1, it is determined that phase C has a phase loss fault.

[0086] The above method determines the number of times the three-phase current polarity is positive based on the polarity variable of the three-phase current; the number of times is compared with a preset threshold to determine the three-phase loss flag. The scheme is simple, not prone to errors, and requires less calculation, which can effectively ensure the efficiency of phase loss detection.

[0087] According to a second aspect of the present invention, an electric motor phase loss detection device is provided. Figure 5 A schematic block diagram of a motor phase loss detection device 500 according to an embodiment of the present invention is shown. Figure 5 As shown, the device 500 may include: a working condition differentiation module 510, a high current detection module 520, and a low current detection module 530.

[0088] The operating condition differentiation module 510 is used to obtain the magnitude of the current current vector of the motor, so as to determine whether the current current is a large current or a small current based on the magnitude of the magnitude.

[0089] The high current detection module 520 is used to detect phase loss in the motor based on the integral of the amplitude of the current current vector when the current is high.

[0090] The low current detection module 530 is used to detect phase loss in the motor based on the polarity of the current when the current is low.

[0091] According to a third aspect of the present invention, an electronic device is also provided. Figure 6 A schematic block diagram of an electronic device 600 according to an embodiment of the present invention is shown. Figure 6 As shown, the electronic device 600 may include a processor 610 and a memory 620. The memory 620 stores computer program instructions, which are executed by the processor 610 to perform the motor phase loss detection method described above.

[0092] According to a fourth aspect of the present invention, a storage medium is also provided, on which program instructions are stored, which, when executed, perform the motor phase loss detection method described above. The storage medium may, for example, include a storage component of a tablet computer, a hard disk of a computer, a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a portable compact disc read-only memory (CD-ROM), a USB memory, or any combination of the above storage media. The computer-readable storage medium may be any combination of one or more computer-readable storage media.

[0093] Those skilled in the art can understand the specific details and beneficial effects of the motor phase loss detection device, electronic equipment, and storage medium by reading the above description of the motor phase loss detection method, and will not be repeated here for the sake of brevity.

[0094] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and / or device 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.

[0095] 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.

[0096] Furthermore, 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. The integrated unit can be implemented in hardware or as a software functional unit.

[0097] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it 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 all 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, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0098] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit it. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A method for detecting phase loss in a motor, characterized in that, include: Obtain the magnitude of the current current vector of the motor, and determine whether the current current is a large current or a small current based on the magnitude of the magnitude; If the current current is a large current, the motor is subjected to phase loss detection based on the integral of the magnitude of the current current vector. When the current current is low, the motor is subjected to phase loss detection based on the polarity of the current current, including: obtaining the current vector angles of the three-phase currents at multiple points of the motor, so as to determine the polarity variables of the three-phase currents based on the current vector angles; determining the three-phase phase loss flag based on the polarity variables of the three-phase currents; and determining whether the motor has a phase loss fault based on the three-phase phase loss flag.

2. The motor phase loss detection method as described in claim 1, characterized in that, The step of obtaining the magnitude of the current vector of the motor, and determining whether the current current is a large current or a small current based on the magnitude of the magnitude, includes: The current carrier frequency ratio is calculated based on the carrier frequency and the electrical frequency of the motor. A count is set during a carrier cycle interruption of the motor to determine the sampling count step size based on the carrier frequency ratio and the count; When the sampling time is equal to an integer multiple of the sampling counting step size, the three-phase current of the motor is collected, and the excitation current, torque current and resolver angle are obtained simultaneously. Calculate the magnitude of the current vector based on the excitation current and the torque current; The magnitude of the current current vector is compared with a preset switching threshold. When the magnitude is less than the preset switching threshold, the current current is determined to be a small current. When the magnitude is greater than or equal to the preset switching threshold, the current current is determined to be a large current.

3. The motor phase loss detection method as described in claim 2, characterized in that, The step of calculating the magnitude of the current vector based on the excitation current and the torque current includes: The magnitude of the current current vector is calculated using the following formula: ,in, This indicates the magnitude of the current current vector. This refers to the excitation current. This refers to the torque current.

4. The motor phase loss detection method as described in claim 2, characterized in that, The step of calculating the current carrier frequency ratio based on the carrier frequency and the electrical frequency of the motor includes: The current carrier frequency ratio is calculated using the following formula: ,in, This indicates the carrier frequency ratio. Indicates the carrier period, The electric period of the motor is represented by the carrier period, which is the reciprocal of the carrier frequency. The electric period is the reciprocal of the electric frequency, which is calculated based on the motor's rotational speed.

5. The motor phase loss detection method according to any one of claims 1 to 4, characterized in that, For the case where the current current is a large current, the motor is subjected to phase loss detection based on the integral of the magnitude of the current current vector, including: After taking the absolute value of the current value of any phase of the three-phase current collected from multiple points of the motor, the maximum value of the absolute value is removed, and then the remaining absolute values ​​are summed to obtain the current integral value of any phase of the three-phase current. The integral value of the current is compared with the integral threshold of the phase loss current to obtain the three-phase phase loss flag. Based on the three-phase phase loss flag, it is determined whether the motor has a phase loss fault.

6. The motor phase loss detection method as described in claim 1, characterized in that, in, The step of determining the three-phase loss flag bit based on the polarity variable of the three-phase current includes: Based on the polarity variables of the three-phase currents, determine the number of times the three-phase currents are positive. The number of times is compared with a preset number threshold to determine the three-phase phase loss flag.

7. A motor phase loss detection device, characterized in that, include: The operating condition differentiation module is used to obtain the magnitude of the current current vector of the motor, so as to determine whether the current current is a large current or a small current based on the magnitude of the magnitude. A high-current detection module is used to detect a phase loss in the motor based on the integral of the amplitude of the current current vector when the current current is a high current. The low-current detection module is used to detect phase loss of the motor based on the polarity of the current current when the current is low. This includes: acquiring the current vector angles of the three-phase currents at multiple points on the motor to determine the polarity variables of the three-phase currents based on the current vector angles; determining a three-phase phase loss flag based on the polarity variables of the three-phase currents; and determining whether the motor has experienced a phase loss fault based on the three-phase phase loss flag.

8. An electronic device, characterized in that, It includes a processor and a memory, wherein the memory stores computer program instructions, which, when executed by the processor, are used to perform the motor phase loss detection method as described in any one of claims 1 to 6.

9. A computer storage medium storing program instructions, which, when executed, perform the motor phase loss detection method as described in any one of claims 1 to 6.

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