Method and device for evaluating motor controller, electronic device and storage medium

Abstract

The application discloses an evaluation method and device of a motor controller, electronic equipment and a storage medium. The method comprises the following steps: determining a scene working condition and a safety target of the motor controller; determining parameter values of related factors influencing the safety target; constructing a function block diagram of the motor controller under the scene working condition based on a task profile; constructing a fault tree model with a safety target violation as a top event based on the function block diagram; and performing quantitative analysis on the top event according to the parameter values and the fault tree model to obtain an analysis result of the top event, so as to optimize the motor controller according to the analysis result. Thus, the safety target is modeled by a fault tree, the weak link of the motor controller system is found out according to the quantitative analysis result of the fault tree, and design optimization and improvement are performed, so that the safety and reliability of the motor controller are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of motor controller, and particularly relates to a motor controller evaluation method, an evaluation device, an electronic device and a storage medium. BACKGROUND

[0002] Electronic and intelligent is the mainstream development trend of new energy vehicles, and many key device functions in vehicles will rely on vehicle electronic technology to realize. With the continuous improvement of the intelligentization and networking of autonomous vehicles, the variability of vehicle working environment, the complexity of traffic environment and the diversity of driving tasks all force vehicle electronic products to complete the specified functions within the specified time, which puts forward extremely high requirements.

[0003] The motor controller, as a power conversion unit connecting the high-voltage battery and the motor in the new energy vehicle, is the core of the motor drive and control system, mainly composed of IGBT power semiconductor modules, control circuits and drive circuits and other hardware. The motor controller will be affected by environmental factors such as high temperature, high humidity, low temperature, temperature rapid change and severe vibration during operation. When the motor controller fails, it will cause serious harm to the driver, passengers and pedestrians. Therefore, how to improve the high safety and high reliability of the motor controller becomes particularly important. SUMMARY

[0004] The present application aims to at least solve one of the technical problems in the related art. To this end, the first object of the present application is to provide a motor controller evaluation method, which finds out the weak links of the motor controller system by quantitative analysis of the fault tree according to the fault tree modeling of the safety target, and optimizes the design for improvement, thereby improving the safety and reliability of the motor controller.

[0005] The second object of the present application is to provide a computer readable storage medium.

[0006] The third object of the present application is to provide an electronic device.

[0007] The fourth object of the present application is to provide a motor controller evaluation device.

[0008] To achieve the above-mentioned objects, the first aspect of the present application provides a motor controller evaluation method, comprising: determining the scene working condition and safety target of the motor controller; determining the parameter value of the related factor affecting the safety target; constructing a function block diagram of the motor controller under the scene working condition based on the task profile; constructing a fault tree model with the violation of the safety target as the top event based on the function block diagram; and performing quantitative analysis on the top event according to the parameter value and the fault tree model to obtain the analysis result of the top event, so as to optimize the motor controller according to the analysis result.

[0009] According to the evaluation method for a motor controller based on embodiments of the present invention, the operating scenarios and safety objectives of the motor controller are determined, and the parameter values ​​of relevant factors affecting the safety objectives are identified. Based on the task profile, a functional block diagram of the motor controller under the operating scenarios is constructed. Then, based on the functional block diagram, a fault tree model with a violation of the safety objective as the top event is constructed. Quantitative analysis of the top event is then performed based on the parameter values ​​and the fault tree model to obtain the analysis results, which are used to optimize the motor controller. Thus, by modeling the safety objectives using a fault tree and identifying the weak points of the motor controller system based on the quantitative analysis results of the fault tree, design optimization and improvement are carried out, thereby continuously improving the safety and reliability of the motor controller.

[0010] According to one embodiment of the present invention, the evaluation method for a motor controller further includes: performing functional failure analysis on the motor controller to determine the failure mode of the motor controller under the scenario conditions, and determining the safety mechanism corresponding to the failure mode; and constructing a fault tree model with the violation of the safety objective as the top event based on the functional block diagram, failure mode and safety mechanism.

[0011] According to one embodiment of the present invention, determining the parameter values ​​of relevant factors affecting safety objectives includes: classifying relevant factors based on failure modes; when the relevant factor is a critical factor, determining the parameter values ​​of the relevant factor based on the scenario conditions; when the relevant factor is a non-critical factor, determining the parameter values ​​of the relevant factor based on design values.

[0012] According to one embodiment of the present invention, quantitative analysis of the top event is performed based on parameter values ​​and a fault tree model to obtain the analysis result of the top event, including: calculating the failure rate of the bottom events in the fault tree model based on parameter values; calculating the failure rate of the top event based on the failure rate of the bottom events and the event timing of the fault tree model; and using the failure rate of the top event as the analysis result of the top event.

[0013] According to one embodiment of the present invention, the evaluation method for a motor controller further includes: determining the minimum cut set of the bottom events in the fault tree model that affect the occurrence of the top event, so as to optimize the motor controller based on the minimum cut set.

[0014] According to one embodiment of the present invention, the evaluation method for the motor controller further includes: performing uncertainty and sensitivity analysis on key factors among the relevant factors based on the analysis results of the top event and the minimum cut set of the bottom event, obtaining uncertainty and sensitivity analysis results, so as to optimize the motor controller according to the uncertainty and sensitivity analysis results.

[0015] According to one embodiment of the present invention, sensitivity analysis includes local sensitivity analysis and global sensitivity analysis.

[0016] To achieve the above objectives, a second aspect of the present invention provides a computer-readable storage medium having a program stored thereon that, when executed by a processor, implements the evaluation method of the motor controller of any of the above embodiments.

[0017] According to the computer-readable storage medium of the present invention, the above-described evaluation method for motor controllers is used to continuously improve the safety and reliability of motor controllers by performing fault tree modeling on safety targets, identifying weak links in the motor controller system based on the quantitative analysis results of the fault tree, and optimizing and improving the design.

[0018] To achieve the above objectives, a third aspect of the present invention provides an electronic device. It includes: a memory, a processor, and a program stored in the memory and executable on the processor. When the processor executes the program, it implements an evaluation method for a motor controller according to any of the above embodiments.

[0019] According to the electronic device of the present invention, the above-described evaluation method for motor controllers is used to continuously improve the safety and reliability of the motor controller by performing fault tree modeling on the safety target, identifying the weak links of the motor controller system based on the quantitative analysis results of the fault tree, and optimizing and improving the design.

[0020] To achieve the above objectives, a fourth aspect of the present invention provides an evaluation device for a motor controller. The device includes: a first determining module for determining the operating scenario and safety objectives of the motor controller; a second determining module for determining the parameter values ​​of relevant factors affecting the safety objectives; a first constructing module for constructing a functional block diagram of the motor controller under the operating scenario based on a task profile; a second constructing module for constructing a fault tree model with a violation of the safety objectives as the top event based on the functional block diagram; and a first analysis module for quantitatively analyzing the top event based on the parameter values ​​and the fault tree model to obtain the analysis results of the top event, so as to optimize the motor controller based on the analysis results.

[0021] According to an embodiment of the present invention, the evaluation device for a motor controller determines the operating scenario and safety objectives of the motor controller through a first determining module, and determines the parameter values ​​of relevant factors affecting the safety objectives through a second determining module. A first construction module then constructs a functional block diagram of the motor controller under the operating scenario based on a task profile. The second construction module constructs a fault tree model with a violation of the safety objective as the top event based on the functional block diagram. Finally, a first analysis module performs quantitative analysis on the top event based on the parameter values ​​and the fault tree model to obtain the analysis results. This allows for optimization of the motor controller based on the analysis results. Thus, by modeling the safety objectives using a fault tree and identifying the weak points in the motor controller system based on the quantitative analysis results, design optimization and improvement are performed, thereby continuously improving the safety and reliability of the motor controller.

[0022] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0023] Figure 1 This is a schematic diagram illustrating the working principle of a motor controller according to an embodiment of the present invention;

[0024] Figure 2 This is a flowchart illustrating an evaluation method for a motor controller according to an embodiment of the present invention;

[0025] Figure 3 This is a structural schematic diagram of a construction function block diagram according to a specific embodiment of the present invention;

[0026] Figure 4 This is a flowchart illustrating an evaluation method for a motor controller according to another embodiment of the present invention;

[0027] Figure 5 This is a schematic diagram of the structure for constructing a fault tree model according to a specific embodiment of the present invention;

[0028] Figure 6 This is a flowchart illustrating an evaluation method for a motor controller according to a specific embodiment of the present invention;

[0029] Figure 7 This is a schematic diagram of the structure of an electronic device according to an embodiment of the present invention;

[0030] Figure 8 This is a schematic diagram of the structure of an evaluation device for a motor controller according to an embodiment of the present invention. Detailed Implementation

[0031] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0032] The motor controller, as the power conversion unit connecting the high-voltage battery and the motor in new energy vehicles, is the core of the motor drive and control system. The working principle of the motor controller is as follows: Figure 1As shown, the motor controller is mainly divided into two parts: a high-voltage section, which converts the high-voltage DC power from the power battery into three-phase AC power to drive the motor; and a low-voltage control section, which includes communication with the vehicle controller and internal communication within the controller, current detection circuits, temperature detection circuits, battery voltage detection circuits, rotor position detection circuits, short-circuit detection circuits, and protection circuits (not shown in the figure). A failure in any module of the motor controller will cause the electric drive system to malfunction, and may even pose a serious threat to personal safety. Therefore, quickly and accurately diagnosing faults in the motor controller and optimizing its design are crucial to ensuring its stable operation.

[0033] To address this, embodiments of the present invention provide an evaluation method, evaluation device, electronic device, and storage medium for a motor controller. Fault tree analysis is used to model the fault logic of the motor controller, diagnose the fault, identify key influencing factors, perform uncertainty sensitivity analysis, optimize the design, and ensure that the motor controller system can operate stably and safely under different operating conditions.

[0034] The following description, with reference to the accompanying drawings, outlines the evaluation method, evaluation apparatus, electronic device, and storage medium for a motor controller according to embodiments of the present invention.

[0035] Figure 2 This is a schematic flowchart illustrating an evaluation method for a motor controller according to an embodiment of the present invention. (Reference) Figure 2 As shown, the evaluation method for this motor controller may include the following steps:

[0036] S101, determine the operating conditions and safety objectives of the motor controller.

[0037] In the operation of an electric vehicle, the motor controller controls the motor to operate according to a set direction, angle, and response time. In the event of a malfunction in the motor controller, it must be brought into a safe state to ensure vehicle control and prevent personal injury to the driver, passengers, and pedestrians.

[0038] When evaluating a motor controller, the first step is to identify the hazards caused by the motor controller failure based on hazard analysis and risk assessment, classify the hazards, determine the corresponding safety objectives, and avoid unacceptable risks.

[0039] Since the safety objectives that violate the operation of the motor controller may differ under different driving scenarios, it is necessary to model and analyze the motor controller's violation of safety objectives in conjunction with the driving scenario.

[0040] Based on the function of the motor controller, there are various driving scenarios related to motor controller failure. For example, according to the type of road, it can include national highway driving scenarios and expressway driving scenarios; according to the road surface conditions, it can include wet and slippery road driving scenarios and icy and snowy road driving scenarios; according to the vehicle status, it can include driving scenarios such as steering, overtaking, braking and acceleration; according to the vehicle's environmental conditions, it can include driving scenarios such as wind, snow, rain, dust, night, and tunnels; according to the personnel, it can include driving environments such as passengers and pedestrians.

[0041] It should be noted that the motor controller can include multiple operating conditions in different driving scenarios, and each operating condition can include multiple safety objectives.

[0042] In this embodiment of the invention, an example is taken of a scenario in which the motor controller operates and the most important safety objective corresponding to that scenario.

[0043] As a concrete example, consider the scenario of an electric vehicle unexpectedly accelerating during normal driving on an urban road. Unexpected acceleration can prevent the driver from quickly assessing the situation and taking appropriate safety measures, potentially endangering pedestrians or other vehicle occupants. Therefore, identifying the key factors causing abnormal acceleration in electric vehicles is crucial. It's understandable that the acceleration value of an electric vehicle is directly related to the wheel input torque. Therefore, one of the most important safety objectives for the motor controller in unexpected acceleration scenarios is the amplitude of the torque estimate monitored each cycle. In practical applications, a safety response is triggered and a safe state is entered when any of the following conditions are met: 1) When the actual torque direction is consistent with the torque request direction, |actual torque value - torque request value| ≥ given value 1; 2) When the actual torque direction is inconsistent with the torque request direction, |actual torque value| ≥ given value 2; 3) The requested torque is zero, |actual torque value| ≥ given value 3.

[0044] S102, Determine the parameter values ​​of relevant factors affecting safety objectives.

[0045] Understandably, after determining the operating scenario and safety objectives of the motor controller according to S101, it is also necessary to determine the parameter values ​​of the relevant factors affecting the safety objectives. It should be noted that the parameter values ​​of these factors can be used for subsequent quantitative evaluation of the motor controller; different parameter values ​​will lead to different results in the subsequent quantitative evaluation of the motor controller.

[0046] S103, based on the task profile, construct the functional block diagram of the motor controller under the scenario conditions.

[0047] It is important to understand that a task profile refers to the temporal description of events and the environment experienced by the motor controller during the specified task completion period. In this embodiment, the task profile may include the operating state of the motor controller, the time and sequence of the environment in which the motor controller is located, and the definition of task completion or fatal failure of the motor controller. The environment includes temperature, humidity, pressure, smoke, radiation, dust, etc. A functional block diagram can be used to describe the functions of the system and the interrelationships between its sub-functions, as well as the system's data flow and internal interfaces. It is a static description of the various functional relationships of the system and can be refined level by level until all functions and sub-functions and their interrelationships can be identified.

[0048] In this embodiment of the invention, after determining the operating scenario and safety objectives of the motor controller, as well as the relevant factors affecting the safety objectives, a functional block diagram of the motor controller under the determined operating scenario can be constructed based on the task profile. The task profile includes the relevant factors affecting the safety objectives.

[0049] As an example, Figure 3 This is a functional block diagram constructed based on a task profile for the motor controller in a scenario where an electric vehicle experiences unexpected acceleration during normal driving on urban roads. The diagram reflects the functions affecting the motor controller's operation and the interrelationships between its sub-functions.

[0050] S104. Based on the functional block diagram, construct a fault tree model with the violation of the safety objective as the top event.

[0051] Specifically, after constructing the functional block diagram, fault tree modeling can be performed based on the diagram to identify the causal events and combinations thereof that cause the violation of the safety objective as the top event. The probability of these events occurring is then calculated, and measures such as design improvements and fault detection are used to reduce the probability of failure. The selection of the top event depends on the specific modeling analysis and can consider fault events that have a significant impact on the system's technical performance, reliability, and security.

[0052] As an example, if a vehicle experiences unexpected acceleration while driving, it will directly endanger the vehicle's driving safety and the driver's personal safety. In this scenario, the top event violating the safety objective is "unexpected acceleration of the vehicle while driving." Therefore, "unexpected acceleration of the vehicle while driving" can be selected as the top event for fault tree analysis. A fault tree is a logical cause-and-effect diagram, whose elements are events and logic gates. Figure 5 Events in a fault tree are used to describe the state of system and component failures. Logic gates link events together, representing the logical relationships between them. Commonly used event symbols in a fault tree are shown in Table 1, and logic gates and symbols are shown in Table 2.

[0053] Table 1 Common event symbols in fault trees

[0054]

[0055] Table 2 Logic gates and their symbols

[0056]

[0057] S105, quantitative analysis of the top event is performed based on parameter values ​​and fault tree model to obtain the analysis results of the top event, so as to optimize the motor controller based on the analysis results.

[0058] Specifically, after determining the parameter values ​​of the relevant factors affecting the safety objective and constructing a fault tree model with the violation of the safety objective as the top event based on the functional block diagram, the probability of the top event failure can be calculated based on the parameter values ​​and the fault tree model to obtain the analysis results of the top event. Then, based on the analysis results, the probability of failure can be reduced by taking measures such as design improvement and effective fault monitoring, thereby achieving the purpose of optimizing the motor controller.

[0059] In the above embodiments, by performing fault tree modeling on the safety objectives, identifying the weak links in the motor controller system based on the quantitative analysis results, and optimizing and improving the design of the weak links, the safety and reliability of the motor controller are improved.

[0060] Figure 4 This is a schematic flowchart illustrating an evaluation method for a motor controller according to another embodiment of the present invention. (Reference) Figure 4 As shown, the evaluation method for this motor controller may include the following steps:

[0061] S201, determine the operating conditions and safety objectives of the motor controller.

[0062] S202, Determine the parameter values ​​of relevant factors affecting safety objectives.

[0063] S203, based on the task profile, construct the functional block diagram of the motor controller under the scenario conditions.

[0064] S204. Perform functional failure analysis on the motor controller to determine the failure mode of the motor controller under the scenario conditions and determine the corresponding safety mechanism for the failure mode.

[0065] S205, based on functional block diagrams, failure modes, and safety mechanisms, constructs a fault tree model with the violation of safety objectives as the top event.

[0066] S206, quantitative analysis of the top event is performed based on parameter values ​​and fault tree model to obtain the analysis results of the top event, so as to optimize the motor controller based on the analysis results.

[0067] It should be noted that, in this embodiment, the descriptions of S201-S203 and S206 can be referred to the descriptions of S101-S103 and S105. To avoid redundancy, they will not be repeated here.

[0068] The following provides a detailed explanation of S204 and S205.

[0069] Specifically, after constructing the functional block diagram of the motor controller under different scenario conditions based on the task profile, it is also necessary to perform functional failure mode analysis (FMD) on the motor controller. This involves identifying all potentially failing functional modules (i.e., modules that malfunction) during the motor controller's operation. Since the failure criteria for the motor controller differ under different scenario conditions, FMD analysis needs to be performed on the motor controller under specific scenario conditions to determine the failure modes and corresponding safety mechanisms. Safety mechanisms are detection measures taken against failure modes to detect faults in advance and bring the motor controller into a safe state, ensuring vehicle control and preventing personal injury to drivers, passengers, and pedestrians. For example, safety mechanisms may include range checks on bus signals, redundancy verification, and monitoring of the controller's underlying hardware and software.

[0070] After determining the failure modes of the motor controller under the specified operating conditions and the corresponding safety mechanisms, a fault tree model can be constructed based on the functional block diagram, failure modes, and safety mechanisms, with the violation of the safety objective as the top event. The fault tree model constructed in this way can more accurately reflect the relevant factors of the violation of the safety objective as the top event and the relationships between these factors. This allows for faster and more accurate fault analysis of the motor controller, facilitating rapid design optimization and improvement, and ultimately enhancing the safety and reliability of the motor controller.

[0071] Figure 5 This is a schematic diagram illustrating the structure of a fault tree model according to a specific embodiment of the present invention. This embodiment uses unexpected acceleration during vehicle operation as the apex event to construct the fault tree model. The construction process of this fault tree model is described in detail below:

[0072] Specifically, constructing a fault tree model requires a thorough understanding of the motor controller and its components, unfolding hierarchically according to system levels. For example, the most likely cause of unexpected acceleration during vehicle operation is excessive inverter torque. This excessive torque could be due to an error in the L1 torque controller output, or the L2 torque monitoring failing to trigger a safe state. The L1 torque controller output error could be caused by a PWM output error or a hardware fault in the drive execution circuit. The L2 torque monitoring failure to trigger a safe state could be due to the L2 layer not detecting an excessive torque signal, detecting an excessive torque signal but failing to trigger a safe state, or a fault in the L3 torque monitoring layer. These faults could also be caused by a malfunction in the U-phase current sensor, V-phase current sensor, W-phase current sensor, etc. It is evident that it is necessary to search layer by layer for all events that affect the top event until the bottom event that affects the top event is found. Based on the causes of each event and their interrelationships, a fault tree model is constructed. Then, based on the qualitative analysis results of the fault tree model, the weak links affecting the system design are identified, and the weak links are optimized and improved, thereby improving the reliability and safety of the motor controller.

[0073] As one possible approach, the parameter values ​​of relevant factors affecting safety objectives can be determined as follows: classifying relevant factors based on failure modes; determining the parameter values ​​of relevant factors based on scenario conditions when the relevant factors are critical; and determining the parameter values ​​of relevant factors based on design values ​​when the relevant factors are non-critical.

[0074] Specifically, after performing functional failure mode analysis on the motor controller, the failure analysis results are obtained. Then, based on these results, relevant factors affecting safety objectives are identified. When a relevant factor is a critical factor, its parameter values ​​are determined based on actual operating conditions. The figures from actual operating conditions are more realistic and better reflect the true dynamic requirements of the motor controller. When a relevant factor is not a critical factor, its parameter values ​​are determined based on design values, thereby reducing workload and achieving the goal of quickly determining parameter values. The design values ​​can be determined by designers based on experience.

[0075] In some embodiments, the quantitative analysis of the top event based on parameter values ​​and the fault tree model can be performed to obtain the analysis results of the top event. This can be done by: calculating the failure rate of the bottom events in the fault tree model based on the parameter values; calculating the failure rate of the top event based on the failure rate of the bottom events and the event time sequence of the fault tree model; and using the failure rate of the top event as the analysis result of the top event.

[0076] Specifically, it involves calculating the probability of top event failure based on the probability of bottom event failure (bottom event failure rate).

[0077] First, the failure rate of the bottom events in the fault tree model can be calculated based on the parameter values. Since the fault tree model reflects the causal events (i.e., bottom events) and combinations of causal events that lead to the failure of the top event, the failure rate of the top event can be calculated based on the failure rate and the event sequence in the fault tree model (i.e., the combination relationships of bottom events affecting the occurrence of the top event). Finally, the failure rate of the top event is used as the analysis result of the top event. Finally, the motor controller can be improved based on the analysis result of the top event, i.e., the failure rate of the top event. For example, a target failure rate can be predetermined; if the calculated failure rate of the top event is greater than the target failure rate, the motor controller can be improved.

[0078] Therefore, based on the quantitative analysis results of the fault tree, the weak links affecting the design of the motor controller system are identified, and these weak links are optimized and improved. For example, higher quality components can be selected, and the reliability and safety of the motor controller can be improved by optimizing the architecture of the motor controller or increasing the diagnostic coverage.

[0079] In some embodiments, the evaluation method for the motor controller further includes: determining the minimum cut set of the bottom events in the fault tree model that affect the occurrence of the top event, so as to optimize the motor controller based on the minimum cut set.

[0080] It's important to note that a cut set is a combination of basic events in a fault tree; it's the set of fundamental events that lead to the top event. In other words, if the occurrence of a set of basic events (basic events) in a fault tree can cause the top event to occur, then this set of basic events (basic events) is called a cut set. A minimal cut set is the minimum set of basic events that can cause the top event to occur. That is, removing any one of the basic events from a cut set will result in it no longer being a cut set.

[0081] In this embodiment of the invention, by identifying the set of all fault modes (bottom events) that lead to the occurrence of the top event, the minimum cut set of the bottom events affecting the occurrence of the top event in the fault tree model is found. Based on this minimum cut set, the motor controller is redesigned, thereby optimizing the motor controller. Thus, based on the qualitative analysis results of the fault tree, weak links affecting the design of the motor controller system are identified, and these weak links are optimized and improved, thereby enhancing the reliability and safety of the motor controller.

[0082] In some embodiments, the evaluation method for the motor controller further includes: performing uncertainty and sensitivity analysis on key factors among the relevant factors based on the analysis results of the top event and the minimum cut set of the bottom event, obtaining uncertainty and sensitivity analysis results, so as to optimize the motor controller according to the uncertainty and sensitivity analysis results.

[0083] It should be noted that most current models assume the distribution parameters of basic random variables are deterministic. However, due to limitations in human understanding and measurement capabilities, this assumption is often unrealistic. Therefore, establishing a reliability analysis model with uncertain distribution parameters for random variables is more reasonable. Thus, in this embodiment of the invention, to ensure the analysis results are more realistic, an uncertainty analysis method is employed. Based on the analysis results of the top event and the minimum cut set of the bottom events, key factors among the relevant factors are analyzed. Furthermore, considering the uncertainty of the original reliability parameters, the task reliability index calculated based on this is also uncertain. In this embodiment of the invention, when performing uncertainty analysis on the bottom events, the bottom event failure modes generally follow an exponential distribution, and a stratified sampling method using Latin hypercube sampling can be used. If the bottom event failure modes do not follow an exponential distribution, Monte Carlo simulation can be used for estimation.

[0084] Furthermore, in order to identify sensitive factors that have a significant impact on key factors among the relevant factors from multiple uncertain factors, sensitivity analysis is also performed on key factors among the relevant factors based on the analysis results of the top event and the minimum cut set of the bottom event. The sensitivity analysis results are then obtained, and the motor controller can be optimized based on the uncertainty and sensitivity analysis results.

[0085] In some embodiments, sensitivity analysis may include local sensitivity analysis and global sensitivity analysis. Local sensitivity analysis reflects the impact of a change in a single input parameter on the output result, while global sensitivity analysis reflects the impact of simultaneous changes in multiple input parameters and the interactions between these parameters on the output result. Parameter selection in local analysis analyzes the impact of changes in a specific type of parameter, such as diagnostic coverage, on the probability of failure due to the top event. Parameter selection in global sensitivity analysis analyzes the impact of simultaneous changes in multiple input parameters, such as diagnostic coverage, failure rate, and the distribution of hazardous failure modes, on the probability of failure due to the top event. In this embodiment, Spearman's rank correlation coefficient and partial rank correlation coefficient can be used to reflect the nonlinear relationship between parameters for sensitivity analysis.

[0086] To enable those skilled in the art to better understand the present invention, a detailed description is provided below with reference to a specific example. Figure 6 As shown in Figure 6, the evaluation method for a motor controller according to a specific embodiment of the present invention may include:

[0087] The process involves: determining the operating scenarios and safety objectives of the motor controller; identifying relevant factors affecting the safety objectives and determining whether these factors are critical. If so, determining the parameter values ​​of these factors based on the actual operating scenarios; otherwise, determining the parameter values ​​based on the design values. Success / failure criteria are defined in conjunction with the operating scenarios, and safety mechanisms are defined. A functional block diagram of the task profile is established based on the specified operating scenarios. A fault tree model is built based on the top event that violates the safety objectives. The failure rate of the bottom events is determined based on the parameter values ​​and the fault tree model, and the failure rate of the top events is quantitatively calculated using the failure rate of the bottom events. The minimum cut set for the top event is determined. Based on the analysis results of the top events and the minimum cut set analysis of the bottom events, uncertainty and sensitivity analysis is performed on the critical influencing factors to identify system weaknesses and implement optimizations and improvements, thereby enhancing the safety and reliability of the motor controller.

[0088] In this process, based on the results of quantitative analysis, qualitative analysis, and uncertainty sensitivity analysis, weak links in the system can be identified and optimized, thereby improving the safety and reliability of the motor controller.

[0089] In summary, the evaluation method for motor controllers according to embodiments of the present invention continuously improves the safety and reliability of motor controllers by performing fault tree modeling on safety targets, identifying weak links in the motor controller system based on the quantitative and qualitative analysis results of the fault tree, and optimizing and improving the design.

[0090] Corresponding to the above embodiments, embodiments of the present invention also propose a computer-readable storage medium having a program stored thereon, which, when executed by a processor, implements the evaluation method of the motor controller of any of the above embodiments.

[0091] According to the computer-readable storage medium of the present invention, the above-described evaluation method for motor controllers is used to continuously improve the safety and reliability of motor controllers by performing fault tree modeling on safety targets, identifying weak links in the motor controller system based on the quantitative and qualitative analysis results of the fault tree, and optimizing and improving the design.

[0092] Corresponding to the above embodiments, the present invention also proposes an electronic device. Figure 7 This is a schematic diagram of the structure of an electronic device according to an embodiment of the present invention. Figure 7 As shown, the electronic device includes: a memory 702, a processor 704, and a program 706 stored in the memory 702 and executable on the processor 704. When the processor executes the program 706, it implements the evaluation method of the motor controller according to any of the above embodiments.

[0093] According to the electronic device of the present invention, the above-described evaluation method for motor controllers is used to continuously improve the safety and reliability of the motor controller by performing fault tree modeling on the safety target, identifying the weak links of the motor controller system based on the quantitative and qualitative analysis results of the fault tree, and optimizing and improving the design.

[0094] Figure 8 This is a schematic diagram of the structure of an evaluation device for a motor controller according to an embodiment of the present invention. (Reference) Figure 8 As shown, the evaluation device 800 for the motor controller includes: a first determination module 801, a second determination module 802, a first construction module 803, a second construction module 804, and a first analysis module 805.

[0095] The first determining module 801 is used to determine the operating scenario and safety objectives of the motor controller; the second determining module 802 is used to determine the parameter values ​​of relevant factors affecting the safety objectives; the first constructing module 803 is used to construct a functional block diagram of the motor controller under the operating scenario based on the task profile; the second constructing module 804 is used to construct a fault tree model with the violation of the safety objective as the top event based on the functional block diagram; and the first analysis module 805 is used to perform quantitative analysis on the top event based on the parameter values ​​and the fault tree model to obtain the analysis results of the top event, so as to optimize the motor controller based on the analysis results.

[0096] In some embodiments, the evaluation device 800 for the motor controller further includes a second analysis module (not shown in the figure), which is used to: perform functional failure analysis on the motor controller to determine the failure mode of the motor controller under the scenario conditions, and determine the safety mechanism corresponding to the failure mode; the second construction module 804 is also used to: construct a fault tree model with the violation of the safety target as the top event based on the functional block diagram, failure mode and safety mechanism.

[0097] In some embodiments, the second determining module 802 is specifically used to: classify relevant factors based on failure modes; when the relevant factor is a critical factor, determine the parameter value of the relevant factor based on the scenario conditions; when the relevant factor is a non-critical factor, determine the parameter value of the relevant factor based on the design value.

[0098] In some embodiments, the first analysis module 805 is specifically used to: calculate the failure rate of the bottom events in the fault tree model based on parameter values; calculate the failure rate of the top events based on the failure rate of the bottom events and the event timing of the fault tree model; and use the failure rate of the top events as the analysis result of the top events.

[0099] In some embodiments, the evaluation apparatus for the motor controller further includes a third determining module (not shown in the figure), which is used to determine the minimum cut set of the bottom events that affect the occurrence of the top event in the fault tree model, so as to optimize the motor controller based on the minimum cut set.

[0100] In some embodiments, the evaluation apparatus for the motor controller further includes a third analysis module (not shown in the figure). The third analysis module is used to perform uncertainty and sensitivity analysis on key factors among the relevant factors based on the analysis results of the top event and the minimum cut set of the bottom event, so as to obtain uncertainty and sensitivity analysis results and optimize the motor controller according to the uncertainty and sensitivity analysis results.

[0101] In some embodiments, sensitivity analysis includes local sensitivity analysis and global sensitivity analysis.

[0102] It should be noted that for details not disclosed in the evaluation device for motor controllers, please refer to the details disclosed in the evaluation method for motor controllers, which will not be repeated here.

[0103] According to an embodiment of the present invention, the evaluation device for a motor controller determines the operating scenario and safety objectives of the motor controller through a first determining module, and determines the parameter values ​​of relevant factors affecting the safety objectives through a second determining module. A first construction module then constructs a functional block diagram of the motor controller under the operating scenario based on a task profile. The second construction module constructs a fault tree model with a violation of the safety objective as the top event based on the functional block diagram. Finally, a first analysis module performs quantitative analysis on the top event based on the parameter values ​​and the fault tree model to obtain the analysis results. Based on the analysis results, the motor controller can be optimized. Thus, by modeling the safety objectives using a fault tree, and by identifying the weak points of the motor controller system based on the quantitative and qualitative analysis results of the fault tree, design optimization and improvement can be performed, thereby continuously improving the safety and reliability of the motor controller.

[0104] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, or in conjunction with, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0105] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0106] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0107] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for evaluating a motor controller, characterized in that, The method includes: Determine the operating conditions and safety objectives of the motor controller; Determine the parameter values ​​of the relevant factors affecting the security objective; Based on the task profile, a functional block diagram of the motor controller under the scenario conditions is constructed. Based on the aforementioned functional block diagram, a fault tree model is constructed with the violation of the aforementioned security objective as the top event. The top event is quantitatively analyzed based on the parameter values ​​and the fault tree model to obtain the analysis results of the top event, so as to optimize the motor controller based on the analysis results; Functional failure analysis is performed on the motor controller to determine the failure mode of the motor controller under the specified operating conditions. The parameter values ​​for determining the relevant factors affecting the security objective include: The relevant factors are classified based on the failure modes; When the relevant factors are key factors, the parameter values ​​of the relevant factors are determined based on the scenario conditions; When the relevant factors are non-critical factors, the parameter values ​​of the relevant factors are determined based on the design values; The quantitative analysis of the top event based on the parameter values ​​and the fault tree model to obtain the analysis results of the top event includes: The failure rate of the bottom event in the fault tree model is calculated based on the parameter values. The failure rate of the top event is calculated based on the failure rate of the bottom event and the event timing of the fault tree model, and the failure rate of the top event is used as the analysis result of the top event. The method further includes: Based on the analysis results of the top event and the minimum cut set of the bottom event, uncertainty and sensitivity analysis are performed on the key factors among the relevant factors to obtain uncertainty and sensitivity analysis results, so as to optimize the motor controller according to the uncertainty and sensitivity analysis results.

2. The evaluation method for a motor controller according to claim 1, characterized in that, The method further includes: Determine the security mechanism corresponding to the failure mode; Based on the functional block diagram, the failure modes, and the security mechanisms, a fault tree model is constructed with the violation of the security objective as the top event.

3. The evaluation method for a motor controller according to any one of claims 1 or 2, characterized in that, The method further includes: Determine the minimum cut set of the bottom events in the fault tree model that affect the occurrence of the top event, so as to optimize the motor controller based on the minimum cut set.

4. The evaluation method for a motor controller according to claim 1, characterized in that, The sensitivity analysis includes local sensitivity analysis and global sensitivity analysis.

5. A computer-readable storage medium, characterized in that, It stores a program that, when executed by a processor, implements the evaluation method for the motor controller according to any one of claims 1-4.

6. An electronic device, characterized in that, include: A memory, a processor, and a program stored in the memory and executable on the processor, wherein the processor, when executing the program, implements the evaluation method for a motor controller according to any one of claims 1-4.

7. An evaluation device for a motor controller, characterized in that, For implementing the evaluation method of the motor controller according to any one of claims 1-4, the apparatus comprises: The first determining module is used to determine the operating conditions and safety objectives of the motor controller. The second determining module is used to determine the parameter values ​​of relevant factors affecting the security objective; The first construction module is used to construct a functional block diagram of the motor controller under the scenario conditions based on the task profile. The second construction module is used to construct a fault tree model with the violation of the security objective as the top event based on the functional block diagram; The first analysis module is used to perform quantitative analysis on the top event based on the parameter values ​​and the fault tree model, and obtain the analysis results of the top event so as to optimize the motor controller based on the analysis results.

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