Method, device, equipment and storage medium for determining abnormality of motor drive current

Abstract

The present application relates to the field of vehicle technology, and discloses a method, device, equipment and storage medium for determining abnormality of a motor drive current, the method comprising: obtaining the input voltage of the motor and the feedback speed of the motor; wherein the feedback speed is the speed of the motor fed back to the speed control loop; according to the input voltage and the feedback speed, calculating an estimated current; according to the estimated current and the feedback current output by the motor, determining whether the drive current of the motor is abnormal; wherein the feedback current is the current fed back by the motor to the current control loop. The present application obtains the input voltage of the motor and the feedback speed fed back to the speed control loop in real time to calculate a real-time estimated current, and compares it with the feedback current fed back by the motor to the current control loop to quickly and accurately determine whether the drive current of the motor is abnormal.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and in particular to a method, device, equipment and storage medium for determining abnormality of motor drive current. Background Art

[0002] At present, the power motors (three-phase asynchronous AC motors or permanent magnet synchronous motors) of new energy electric vehicles all use vector control technology to control the speed or torque of the motors. In the entire control loop, dynamic feedback of the three-phase current and speed feedback of the encoder are required to achieve precise control of the motor torque and / or speed. Therefore, current sampling is very important. If there is a fault in the current sampling, it will affect the power of the whole vehicle and cause a fault shutdown. In severe cases, it will cause the vehicle to lose control and cause serious loss of life, personal injury and property.

[0003] At present, the common improvement solutions are to improve the reliability of current sampling components and to add redundant current sampling hardware to achieve dual backup monitoring. However, the modification of related hardware is very cumbersome, and even if the current sampling hardware is added, it is impossible to accurately identify abnormal conditions of the motor drive current. Summary of the invention

[0004] In view of the above problems, the present application provides a method, device, equipment and storage medium for determining abnormality of motor drive current, which are used to accurately identify abnormal conditions of motor drive current without adding any hardware equipment.

[0005] According to one aspect of the present application, a method for determining an abnormality in a motor drive current is provided, the method comprising: obtaining an input voltage of a motor and a feedback speed of the motor; wherein the feedback speed is the speed of the motor fed back to a speed control loop; calculating an estimated current based on the input voltage and the feedback speed; determining whether the drive current of the motor is abnormal based on the estimated current and a feedback current output by the motor; wherein the feedback current is the current fed back to a current control loop by the motor.

[0006] In an optional manner, the estimated current is calculated based on the input voltage and the feedback speed, and further includes: inputting the input voltage and the feedback speed into an estimation model so that the estimation model outputs the estimated current; wherein the estimation model is a spatial state model of the electrical part of the motor obtained under Park transformation.

[0007] In an optional manner, the abnormality determination method also includes: constructing a differential component equation of the spatial state model with respect to time based on the spatial state value, the first matrix and the second matrix; wherein the first matrix is ​​a matrix related to the feedback speed; constructing a current estimation equation based on the third matrix and the spatial state value; and constructing the estimation model based on the differential component equation and the current estimation equation.

[0008] In an optional manner, determining whether the driving current of the motor is abnormal based on the estimated current and the feedback current output by the motor further includes: if a fault code of the motor encoder is detected, performing a difference operation on the estimated current and the feedback current output by the motor to calculate the difference; if it is detected that the difference is greater than a preset difference, determining that the driving current of the motor is abnormal.

[0009] In an optional manner, the input voltage and the feedback speed of the motor are multiple data collected in multiple acquisition cycles; determining whether the driving current of the motor is abnormal based on the estimated current and the feedback current output by the motor further includes: calculating the variance corresponding to each acquisition cycle based on the input voltage and feedback speed corresponding to each moment in each acquisition cycle; detecting whether the variances corresponding to each acquisition cycle show an increasing trend; if it is detected that the variances corresponding to each acquisition cycle show an increasing trend, determining that the driving current of the motor is abnormal.

[0010] In an optional manner, the collection period is divided into a first collection period, a second collection period and a third collection period in positive time sequence; the detecting whether the variances corresponding to the respective collection periods show an increasing trend further includes: detecting whether the variance corresponding to the third collection period is greater than the variance corresponding to the second collection period, and whether the variance corresponding to the second collection period is greater than the variance corresponding to the first collection period; if both are yes, it is determined that the variances corresponding to the respective collection periods show an increasing trend.

[0011] In an optional manner, the motor is a three-phase asynchronous motor; the abnormality determination method also includes: when it is determined that the driving current of the motor is abnormal, adding the estimated current of the target phase to the actual currents of the other two phases; if the sum obtained by the addition is close to zero, it is determined that the actual current of the target phase is abnormal.

[0012] According to another aspect of the present application, a device for determining an abnormality of a motor driving current is provided, the device comprising: an acquisition module for acquiring an input voltage of a motor and a feedback speed of the motor; wherein the feedback speed is the speed of the motor fed back to a speed control loop; a calculation module for calculating an estimated current based on the input voltage and the feedback speed; and a determination module for determining whether the driving current of the motor is abnormal based on the estimated current and a feedback current output by the motor; wherein the feedback current is the current fed back to a current control loop by the motor.

[0013] According to one aspect of the present application, an electronic device is provided, including: a controller; and a memory for storing one or more programs, which, when the one or more programs are executed by the controller, perform the above-mentioned abnormality determination method.

[0014] According to one aspect of the present application, a computer-readable storage medium is also provided, on which computer-readable instructions are stored. When the computer-readable instructions are executed by a processor of a computer, the computer executes the above-mentioned abnormality determination method.

[0015] According to one aspect of the present application, a computer program product or a computer program is also provided, the computer program product or the computer program comprising computer instructions, the computer instructions being stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device executes the above-mentioned abnormality determination method.

[0016] The present application obtains the input voltage of the motor and the feedback speed fed back to the speed control loop in real time to calculate the real-time estimated current, and compares it with the feedback current fed back to the current control loop by the motor to quickly and accurately determine whether the driving current of the motor is abnormal.

[0017] The above description is only an overview of the technical solution of the embodiment of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0019] Figure 1It is a flowchart of a method for determining abnormality of a motor drive current shown in an exemplary embodiment of the present application.

[0020] Figure 2 This is a schematic diagram of a conventional motor control loop.

[0021] Figure 3 It is a loop schematic diagram of a motor closed-loop control shown in an exemplary embodiment of the present application.

[0022] Figure 4 is based on Figure 1 The exemplary embodiment shown is a flow chart of another method for determining abnormality of a motor drive current.

[0023] Figure 5 It is a schematic diagram of an application scenario of the method for determining abnormality of motor drive current of the present application.

[0024] Figure 6 Detailed description of the invention is given in detail in the following figure: FIG. 1 is a schematic diagram of a device for determining abnormality of a motor drive current according to an exemplary embodiment of the present invention.

[0025] Figure 7 It is a structural diagram of a computer system of an electronic device shown in an exemplary embodiment of the present application. DETAILED DESCRIPTION

[0026] Here, exemplary embodiments will be described in detail, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are only examples of devices and methods consistent with some aspects of the present application as detailed in the attached claims.

[0027] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities may be implemented in software form, or in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0028] The flowcharts shown in the accompanying drawings are only exemplary and do not necessarily include all the contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps can be decomposed, and some operations / steps can be combined or partially combined, so the actual execution order may change according to actual conditions.

[0029] The term "multiple" as used in this application refers to two or more than two. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the related objects are in an "or" relationship.

[0030] The power motors (three-phase asynchronous AC motors or permanent magnet synchronous motors) of existing new energy electric vehicles all use vector control technology to control the motor speed or torque. In the entire control loop, dynamic feedback of the three-phase current and speed feedback of the encoder are required to achieve precise control of the motor torque and / or speed. Therefore, current sampling is crucial. If there is a fault in current sampling, it will affect the power of the entire vehicle and cause a fault shutdown. In severe cases, it will cause the vehicle to lose control and cause serious loss of life, personal injury and property.

[0031] At present, the common improvement solutions are to improve the reliability of current sampling components and to add redundant current sampling hardware to achieve dual backup monitoring. However, the modification of related hardware is very cumbersome, and even if the current sampling hardware is added, it is impossible to accurately identify abnormal conditions of the motor drive current.

[0032] To this end, one aspect of the present application provides a method for determining abnormality of a motor drive current. Figure 1 , Figure 1 1 is a flow chart of a method for determining abnormality of a motor drive current according to an exemplary embodiment of the present application. The abnormality determination method at least includes S110 to S130, which are described in detail as follows:

[0033] S110: Acquire the input voltage of the motor and the feedback speed of the motor; wherein the feedback speed is the speed fed back by the motor to the speed control loop.

[0034] The present application does not limit the collection method of the feedback speed, which may be a speed value obtained by encoder sampling, or a speed value collected by other methods.

[0035] Electric motor control methods for new energy vehicles Figure 2 As shown, Figure 2 Schematic diagram of conventional motor control loop. Among them, the feedback current and feedback speed are fed back to the corresponding current loop and speed loop respectively. According to the mathematical dynamics model of the AC motor (three-phase asynchronous AC motor or permanent magnet synchronous motor), the input voltage and feedback speed of the controlled physical motor can be synchronously input to the mathematical model to obtain the estimated current on the motor rotor from the dynamics model. In this embodiment, without adding any hardware equipment, it is only necessary to obtain the input voltage of the motor and the feedback speed of the motor to quickly calculate the estimated current.

[0036] It is worth noting that although the permanent magnet synchronous motor has no slip between the stator and the rotor and has a different mathematical model compared to the three-phase asynchronous motor, the abnormality determination method of the present application is also applicable to the current abnormality monitoring of the permanent magnet synchronous motor.

[0037] S120: Calculate and obtain estimated current based on input voltage and feedback speed.

[0038] Exemplarily, the input voltage and the feedback speed are input into the estimation model so that the estimation model outputs the estimated current; wherein the estimation model is a spatial state model of the electrical part of the motor obtained under Park transformation.

[0039] The estimation model is a model constructed by combining the principles of dynamics. According to the spatial state value, the first matrix and the second matrix, the differential equation of the spatial state model for time is constructed; wherein the first matrix is ​​a matrix related to the feedback speed; the current estimation equation is constructed according to the third matrix and the spatial state value; and the estimation model is constructed according to the differential equation and the current estimation equation. The following is an exemplary description of the process of establishing the estimation model:

[0040] The three-phase asynchronous motor can be regarded as an LPV (linear time-varying) system. The spatial state model of the electrical part of the three-phase asynchronous AC motor under Park transformation is shown as follows:

[0041]

[0042] y = Cx0;

[0043] in, represents the differential equation of the spatial state model with respect to time, u represents the input voltage, that is, the stator voltage on the α and β axes; Ω m represents the feedback speed of the motor output; y represents the feedback current, that is, the stator current on the α and β axes; A0(Ω m ) represents the first matrix; x0 represents the spatial state value, that is, the rotor flux on the α and β axes; B represents the second matrix; C represents the third matrix; the relevant parameters are as follows:

[0044]

[0045]

[0046]

[0047] R s Represents the stator resistance of the motor winding, R r represents the rotor resistance of the motor winding, M represents the common inductance on the motor winding, and L s Indicates the stator self-inductance on the motor winding, Lr Represents the rotor self-inductance on the motor winding, Z p Indicates the number of pole pairs of the motor.

[0048] S130: Determine whether the driving current of the motor is abnormal based on the estimated current and the feedback current output by the motor; wherein the feedback current is the current fed back by the motor to the current control loop.

[0049] The present application does not limit the collection method of the feedback current, which may be a current value sampled by a sensor, or a current value collected by other methods.

[0050] See also Figure 3 , Figure 3 This is a loop diagram of a motor closed-loop control shown in an exemplary embodiment of the present application. Among them, the stator current monitoring module is a virtual module, not an actual functional module. In this embodiment, it is only necessary to obtain the input voltage of the motor and the feedback speed of the motor to calculate the estimated current, and then perform corresponding data processing on it and the feedback current of the motor output obtained by the stator current monitoring module to accurately determine whether the driving current of the motor is abnormal.

[0051] As an example, it is detected whether a fault code of the motor encoder appears; if a fault code of the motor encoder is detected, the estimated current is subtracted from the feedback current output by the motor to calculate the difference, and it is detected whether the difference is greater than a preset difference. If it is greater, it is determined that the driving current of the motor is abnormal.

[0052] In another exemplary embodiment, the stator current monitoring module continuously collects relevant data to obtain the input voltage and feedback speed corresponding to each moment in multiple collection cycles. According to the input voltage and feedback speed corresponding to each moment in each collection cycle, the variance corresponding to each collection cycle is calculated; it is detected whether the variances corresponding to each collection cycle show an increasing trend; if it is detected that the variances corresponding to each collection cycle show an increasing trend, it is determined that the driving current of the motor is abnormal.

[0053] For example, the acquisition cycle is divided into the first acquisition cycle, the second acquisition cycle and the third acquisition cycle according to the positive sequence time. By comparing the variance between two adjacent acquisition cycles, it can be determined whether the variance is increasing. Specifically, it is detected whether the variance corresponding to the third acquisition cycle is greater than the variance corresponding to the second acquisition cycle, and whether the variance corresponding to the second acquisition cycle is greater than the variance corresponding to the first acquisition cycle; if both are yes, it is determined that the variances corresponding to the various acquisition cycles are increasing, and further it can be determined that the driving current of the motor is abnormal.

[0054] This embodiment obtains the input voltage of the motor and the feedback speed fed back to the speed control loop in real time to calculate the real-time estimated current, and compares it with the feedback current fed back to the current control loop by the motor to quickly and accurately determine whether the driving current of the motor is abnormal.

[0055] This embodiment does not require any hardware improvement or redundant hardware for current sampling monitoring. The abnormal motor drive current monitoring is completed at the software level alone, and it can quickly and accurately determine whether the motor drive current is abnormal.

[0056] In another exemplary embodiment of the present application, how to determine the abnormal phase in the three-phase asynchronous motor is described in detail. Figure 4 , Figure 4 is based on Figure 1 The exemplary embodiment shown is a flow chart of another method for determining abnormality of a motor drive current. The abnormality determination method is as follows: Figure 1 On the basis of S110 to S130 shown in the figure, S410 to S420 are also included; wherein the motor is a three-phase asynchronous motor or a permanent magnet synchronous motor, which is described in detail as follows:

[0057] S410: When it is determined that the driving current of the motor is abnormal, the estimated current of the target phase is added to the actual currents of the other two phases.

[0058] S420: If the sum value obtained by adding is close to zero, it is determined that the actual current of the target phase is abnormal.

[0059] Since the three-phase current has a symmetrical characteristic, that is, the sum of the three-phase current should be equal to or close to zero, when the hardware current sampling is abnormal (that is, the motor drive current is determined to be abnormal), if the estimated value of the target phase (such as U phase) is added to the actual value of the other two phases (V and W phases) and is close to zero, it can be determined that the current sampling of the target phase (U phase) is abnormal.

[0060] This embodiment further illustrates how to use the symmetrical characteristics of the three-phase current to determine the abnormal phase, that is, when it is determined that the driving current of the motor is abnormal, the estimated current of the target phase is added to the actual currents of the other two phases. If the sum is close to zero, it can be quickly determined that the actual current of the target phase is abnormal, and the abnormal phase can be quickly located.

[0061] In another exemplary embodiment of the present application, the application scenarios of the above-mentioned multiple abnormality determination methods are exemplarily described. Figure 5 , Figure 5It is a schematic diagram of an application scenario of the method for determining abnormality of motor drive current of the present application, wherein the vehicle end 100, the motor 200 and the monitor 300 are included, and the three ends can be connected by wireless communication, and the present application does not limit the connection method between them.

[0062] The monitor 300 can be Figure 5 As shown, it is placed in the vehicle end 100, and can also be placed outside the vehicle end 100. The motor 200 is a three-phase asynchronous AC motor or a permanent magnet synchronous motor in the AC motor. The monitor 300 can execute the abnormality determination method of the motor drive current shown in any of the above exemplary embodiments, and the exemplary description is as follows:

[0063] The monitor 300 obtains the input voltage of the motor 200 and the feedback speed of the motor; wherein, the feedback speed is the speed of the motor 200 fed back to the speed control loop; the monitor 300 calculates the estimated current based on the input voltage and the feedback speed; the monitor 300 determines whether the driving current of the motor 200 is abnormal based on the estimated current and the feedback current output by the motor 200; wherein, the feedback current is the current fed back to the current control loop by the motor 200.

[0064] Among them, the monitor 300 can be an independent physical server, or it can be a server cluster or distributed system composed of multiple physical servers, where multiple servers can form a blockchain, and the server is a node on the blockchain. The monitor 300 can also be a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communications, middleware services, domain name services, security services, CDN (Content Delivery Network) and big data and artificial intelligence platforms, and there is no restriction on this here.

[0065] Another aspect of the present application also provides a device for determining abnormality of a motor drive current, such as Figure 6 As shown, Figure 6 It is a structural schematic diagram of an abnormality determination device for a motor drive current shown in an exemplary embodiment of the present application. The abnormality determination device 600 includes: an acquisition module 610, which is used to obtain the input voltage of the motor and the feedback speed of the motor; wherein the feedback speed is the speed of the motor fed back to the speed control loop; a calculation module 630, which is used to calculate the estimated current according to the input voltage and the feedback speed; a determination module 650, which is used to determine whether the drive current of the motor is abnormal according to the estimated current and the feedback current output by the motor; wherein the feedback current is the current fed back to the current control loop by the motor.

[0066] In an optional manner, the calculation module 630 further includes: a calculation unit, which is used to input the input voltage and feedback speed into the estimation model so that the estimation model outputs an estimated current; wherein the estimation model is a spatial state model of the electrical part of the motor obtained under Park transformation.

[0067] In an optional manner, the abnormality determination device 600 also includes: a first construction module, used to construct a differential component equation of the spatial state model with respect to time based on the spatial state value, the first matrix and the second matrix; wherein the first matrix is ​​a matrix related to the feedback speed; a second construction module, used to construct a current estimation equation based on the third matrix and the spatial state value; and a third construction module, used to construct an estimation model based on the differential component equation and the current estimation equation.

[0068] In an optional manner, the determination module 650 further includes: a difference calculation unit, which is used to perform a difference operation on the estimated current and the feedback current output by the motor to calculate the difference if a fault code of the motor encoder is detected; and a first abnormality determination unit, which is used to determine that the driving current of the motor is abnormal if a difference greater than a preset difference is detected.

[0069] In an optional manner, the input voltage and the feedback speed of the motor are multiple data collected in multiple acquisition cycles; the determination module 650 further includes: a variance calculation unit, used to calculate the variance corresponding to each acquisition cycle according to the input voltage and feedback speed corresponding to each moment in each acquisition cycle; a trend detection unit, used to detect whether the variances corresponding to each acquisition cycle show an increasing trend; a trend increase determination unit, used to determine that the driving current of the motor is abnormal if it is detected that the variances corresponding to each acquisition cycle show an increasing trend.

[0070] In an optional manner, the collection period is divided into a first collection period, a second collection period and a third collection period in positive time sequence; the trend detection unit further includes: a variance size detection module, used to detect whether the variance corresponding to the third collection period is greater than the variance corresponding to the second collection period, and whether the variance corresponding to the second collection period is greater than the variance corresponding to the first collection period; and a determination module, used to determine that if both are yes, then the variances corresponding to each collection period show an increasing trend.

[0071] In an optional manner, the motor is a three-phase asynchronous motor; the abnormality determination device 600 also includes: a phase current addition module, which is used to add the estimated current of the target phase with the actual currents of the other two phases when it is determined that the driving current of the motor is abnormal; a phase current abnormality determination module, which is used to determine that the actual current of the target phase is abnormal if the sum obtained by the addition is close to zero.

[0072] The abnormality determination device of the present application obtains the input voltage of the motor and the feedback speed fed back to the speed control loop in real time to calculate the real-time estimated current, and compares it with the feedback current fed back to the current control loop by the motor to quickly and accurately determine whether the driving current of the motor is abnormal.

[0073] It should be noted that the abnormality determination device provided in the above embodiment and the abnormality determination method provided in the above embodiment belong to the same concept, wherein the specific manner in which each module and unit performs operations has been described in detail in the method embodiment and will not be repeated here.

[0074] Another aspect of the present application provides an electronic device, including: a controller; and a memory for storing one or more programs, which, when executed by the controller, execute the above-mentioned abnormality determination method.

[0075] See also Figure 7 , Figure 7 1 is a schematic diagram of the structure of a computer system of an electronic device shown in an exemplary embodiment of the present application, which shows a schematic diagram of the structure of a computer system of an electronic device suitable for implementing an embodiment of the present application.

[0076] It should be noted that Figure 7 The computer system 700 of the electronic device shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0077] like Figure 7 As shown, the computer system 700 includes a central processing unit (CPU) 701, which can perform various appropriate actions and processes according to the program stored in the read-only memory (ROM) 702 or the program loaded from the storage part 708 to the random access memory (RAM) 703, such as executing the method in the above embodiment. In the RAM 703, various programs and data required for system operation are also stored. The CPU 701, ROM 702 and RAM 703 are connected to each other through a bus 704. An input / output (I / O) interface 705 is also connected to the bus 704.

[0078] The following components are connected to the I / O interface 705: an input section 706 including a keyboard, a mouse, etc.; an output section 707 including a cathode ray tube (CRT), a liquid crystal display (LCD), etc., and a speaker, etc.; a storage section 708 including a hard disk, etc.; and a communication section 709 including a network interface card such as a LAN (Local Area Network) card, a modem, etc. The communication section 709 performs communication processing via a network such as the Internet. A drive 710 is also connected to the I / O interface 705 as needed. A removable medium 711, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive 710 as needed so that a computer program read therefrom is installed into the storage section 708 as needed.

[0079] In particular, according to an embodiment of the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present application includes a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a computer program for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication section 709, and / or installed from a removable medium 711. When the computer program is executed by a central processing unit (CPU) 701, various functions defined in the system of the present application are executed.

[0080] It should be noted that the computer-readable medium shown in the embodiment of the present application can be a computer-readable signal medium or a computer-readable storage medium or any combination of the above two. The computer-readable storage medium can be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination of the above. More specific examples of computer-readable storage media can include, but are not limited to: an electrical connection with one or more 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), a 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 of the above. In the present application, a computer-readable storage medium can be any tangible medium containing or storing a program, which can be used by an instruction execution system, device or device or used in combination with it. In the present application, a computer-readable signal medium can include a data signal propagated in a baseband or as a part of a carrier wave, wherein a computer-readable computer program is carried. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. Computer-readable signal media may also be any computer-readable medium other than computer-readable storage media, which may send, propagate, or transmit programs for use by or in conjunction with an instruction execution system, apparatus, or device. The computer program contained on the computer-readable medium may be transmitted using any appropriate medium, including but not limited to: wireless, wired, etc., or any suitable combination of the above.

[0081] The flowchart and block diagram in the accompanying drawings illustrate the possible architecture, functions and operations of the system, method and computer program product according to various embodiments of the present application. Wherein, each box in the flowchart or block diagram can represent a module, a program segment, or a part of the code, and the above-mentioned module, program segment, or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order than the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flowchart, and the combination of boxes in the block diagram or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0082] The units involved in the embodiments described in this application may be implemented by software or hardware, and the units described may also be set in a processor. The names of these units do not, in some cases, constitute limitations on the units themselves.

[0083] Another aspect of the present application further provides a computer-readable storage medium having a computer program stored thereon, which implements the above-mentioned abnormality determination method when the computer program is executed by a processor. The computer-readable storage medium may be included in the electronic device described in the above embodiment, or may exist independently without being assembled into the electronic device.

[0084] Another aspect of the present application also provides a computer program product or a computer program, which includes a computer instruction stored in a computer-readable storage medium. A processor of a computer device reads the computer instruction from the computer-readable storage medium, and the processor executes the computer instruction, so that the computer device executes the abnormality determination method provided in each of the above embodiments.

[0085] According to one aspect of an embodiment of the present application, a computer system is also provided, including a central processing unit (CPU), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) or a program loaded from a storage portion into a random access memory (RAM), such as executing the method in the above embodiment. In RAM, various programs and data required for system operation are also stored. CPU, ROM and RAM are connected to each other via a bus. An input / output (I / O) interface is also connected to the bus.

[0086] The following components are connected to the I / O interface: an input part including a keyboard, a mouse, etc.; an output part including a cathode ray tube (CRT), a liquid crystal display (LCD), etc., and a speaker; a storage part including a hard disk, etc.; and a communication part including a network interface card such as a LAN (Local Area Network) card, a modem, etc. The communication part performs communication processing via a network such as the Internet. A drive is also connected to the I / O interface as needed. Removable media, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., are installed on the drive as needed so that the computer program read therefrom is installed into the storage part as needed.

[0087] The above content is only a preferred exemplary embodiment of the present application and is not intended to limit the implementation scheme of the present application. A person skilled in the art can easily make corresponding changes or modifications based on the main concept and spirit of the present application. Therefore, the scope of protection of the present application shall be based on the scope of protection required by the claims.

Claims

1. A method for determining abnormality of motor drive current, characterized in that: The abnormality determination method comprises: Acquire the input voltage of the motor and the feedback speed of the motor; wherein the feedback speed is the speed of the motor fed back to the speed control loop; Calculating an estimated current according to the input voltage and the feedback speed; Whether the driving current of the motor is abnormal is determined according to the estimated current and the feedback current output by the motor; wherein the feedback current is the current fed back by the motor to the current control loop.

2. The abnormality determination method according to claim 1, characterized in that: The step of calculating the estimated current according to the input voltage and the feedback speed further comprises: The input voltage and the feedback speed are input into an estimation model so that the estimation model outputs an estimated current; wherein the estimation model is a spatial state model of the electrical part of the motor obtained under Park transformation.

3. The abnormality determination method according to claim 2, characterized in that: The abnormality determination method further includes: According to the space state value, the first matrix and the second matrix, the differential equation of the space state model for time is constructed; wherein the first matrix is ​​a matrix related to the feedback speed; the space state value ; The first matrix , , , , ; represents the stator resistance of the motor winding, represents the rotor resistance of the motor winding, represents the common inductance on the motor windings, represents the stator self-inductance on the motor winding, represents the rotor self-inductance on the motor winding, Indicates the number of pole pairs of the motor, Represents the feedback speed of the motor output; the second matrix , ; The current estimation equation is constructed based on the third matrix and the spatial state value. ; The estimation model is constructed based on the differential equation and the current estimation equation.

4. The abnormality determination method according to claim 1, characterized in that: The step of determining whether the driving current of the motor is abnormal according to the estimated current and the feedback current output by the motor further comprises: If a fault code of the motor encoder is detected, the estimated current is subtracted from the feedback current output by the motor to calculate the difference; If it is detected that the difference is greater than a preset difference, it is determined that the driving current of the motor is abnormal.

5. The abnormality determination method according to claim 1, characterized in that: The input voltage and the feedback speed of the motor are multiple data collected in multiple collection cycles; The step of determining whether the driving current of the motor is abnormal according to the estimated current and the feedback current output by the motor further comprises: According to the input voltage and feedback speed corresponding to each moment in each acquisition cycle, the variance corresponding to each acquisition cycle is calculated; Check whether the variances corresponding to each acquisition period show an increasing trend; If it is detected that the variances corresponding to the various acquisition cycles show an increasing trend, it is determined that the driving current of the motor is abnormal.

6. The abnormality determination method according to claim 5, characterized in that: The collection cycle is divided into the first collection cycle, the second collection cycle and the third collection cycle according to the positive time sequence; The detecting whether the variances corresponding to each acquisition cycle show an increasing trend further includes: Detecting whether the variance corresponding to the third acquisition period is greater than the variance corresponding to the second acquisition period, and whether the variance corresponding to the second acquisition period is greater than the variance corresponding to the first acquisition period; If all are yes, it is determined that the variances corresponding to each collection period are increasing.

7. The abnormality determination method according to any one of claims 1 to 6, characterized in that: The motor is a three-phase asynchronous motor; the abnormality determination method further includes: When it is determined that the driving current of the motor is abnormal, the estimated current of the target phase is added to the actual currents of the other two phases; If the sum value obtained by adding is close to zero, it is determined that the actual current of the target phase is abnormal.

8. A device for determining abnormality of motor drive current, characterized in that: The abnormality determination device comprises: An acquisition module, used for acquiring an input voltage of a motor and a feedback speed of the motor; wherein the feedback speed is the speed of the motor fed back to a speed control loop; A calculation module, used for calculating an estimated current according to the input voltage and the feedback speed; A determination module is used to determine whether the driving current of the motor is abnormal according to the estimated current and the feedback current output by the motor; wherein the feedback current is the current fed back by the motor to the current control loop.

9. An electronic device, characterized in that: include: Controller; A memory for storing one or more programs, which, when executed by the controller, enables the controller to implement the abnormality determination method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: Computer-readable instructions are stored thereon, and when the computer-readable instructions are executed by a processor of a computer, the computer is caused to execute the abnormality determination method according to any one of claims 1 to 7.

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