Electric drive system operation control method and device, electric vehicle and storage medium

Abstract

The invention discloses an electric driving system operation control method and device, an electric vehicle and a storage medium, and the method comprises the steps: obtaining a feature value of a key feature causing failure of parts in an electric driving system in the electric driving system in real time, and judging whether the feature value is greater than a preset feature value threshold value or not; when the characteristic value is greater than the characteristic value threshold value, starting to count the running time of the part when the characteristic value exceeds the characteristic value threshold value; obtaining a maximum duration preset value allowed by the current working condition according to the key features; calculating and counting the ratio of the time to the maximum duration preset value, and judging whether the ratio is greater than a ratio threshold value or not; and when the specific value is larger than or equal to a specific value threshold value, early warning is sent to the vehicle control unit, so that the vehicle control unit controls the electric driving system to exit from the operation interval where failure is likely to happen. According to the scheme, the electric driving system can obtain higher rotating speed capability on the premise of safe use, or cost reduction is realized by using parts with higher cost performance under the same output capability.

Description

Technical Field

[0001] The present invention relates to the technical field of electric vehicle control, and in particular to an electric drive system operation control method, device, electric vehicle and storage medium. Background Art

[0002] At present, the main contradiction that limits the continuous high-speed operation of the electric drive system is that the motor will generate too much heat when it continues to have high torque and high speed, causing overheating and failure of the motor, reducer or its related components such as bearings, power devices, etc. For the control and prevention of overheating and failure of components of the electric drive system of electric vehicles, the several solutions existing in the existing technology have their own shortcomings.

[0003] For example, some literature proposes to add temperature sensors or oil pumps to the reducer or motor to monitor temperature and efficiently cool and dissipate heat, but this method requires redesigning and adding sensors to the product, which has low feasibility; some literature proposes to increase the heat dissipation area of ​​the bearing and the heat exchange efficiency during cooling by optimizing the distribution position and structure of the mechanical components of the motor or electric drive reducer, but this method also requires redesigning the product and cannot be optimized on existing products, and has poor flexibility; some literature proposes to estimate the bearing temperature through the thermal model of the motor bearing or the motor rotor temperature through the thermal model, which can then be limited according to the temperature, but today's thermal models are difficult to cover all operating conditions, and the accuracy of temperature estimation under complex vehicle operating conditions is questionable, and there is still a risk of overheating and failure of the motor or other components. Summary of the invention

[0004] In view of the above problems, the present invention is proposed to provide an electric drive system operation control method, device, electric vehicle and storage medium that overcome the above problems or at least partially solve the above problems.

[0005] According to one aspect of the present invention, a method for controlling operation of an electric drive system is provided, the method comprising:

[0006] Acquire in real time a characteristic value of a key characteristic of an electric drive system that causes a component failure in the electric drive system, and determine whether the characteristic value is greater than a preset characteristic value threshold;

[0007] When the characteristic value is greater than the characteristic value threshold, start counting the time for which the component runs when the characteristic value exceeds the characteristic value threshold;

[0008] According to the key feature, a predetermined maximum duration allowed by the current working condition is obtained;

[0009] Calculate and count the ratio of the time to the predetermined maximum duration value, and determine whether the ratio is greater than a ratio threshold;

[0010] When the ratio is equal to or greater than a ratio threshold, an early warning is issued to the vehicle controller so that the vehicle controller controls the electric drive system to exit an operating range prone to failure.

[0011] In some embodiments, obtaining the characteristic value of the key characteristic that causes each component failure in the electric drive system includes:

[0012] Acquire the speed and torque signal values ​​of the electric drive system in real time;

[0013] According to the speed and the torque signal value, determining whether the current operating condition is in an operating range prone to failure;

[0014] If the current operating condition is in an operating range prone to failure, the method is executed.

[0015] In some implementations, obtaining a predetermined maximum duration value allowed by the current operating condition according to the key feature includes:

[0016] According to the characteristic value of the key characteristic, a table is consulted to obtain a predetermined maximum duration time that the component can maintain operation under the current working condition;

[0017] The table is pre-drawn based on the mechanical properties of the components, thermal simulation results of the electric drive system, two-wheel drive bench endurance test results and / or vehicle test results.

[0018] In some implementations, calculating and counting the ratio of the time to the predetermined maximum duration, and determining whether the ratio is greater than a ratio threshold comprises:

[0019] There are multiple components, and each component is assigned a weight value, and the sum of the weight values ​​is 1;

[0020] Calculating the product of the ratio of each component and the weight value of the component respectively;

[0021] Calculate the sum of the products, and determine whether the sum is greater than 1;

[0022] The components include bearings, motor shafts, gears, stator windings, rotor magnets or electronic devices.

[0023] In some embodiments, the method further comprises:

[0024] The timing starts from when it is determined that the electric drive system exits the operating range prone to failure. When the exit time is greater than a preset time, the ratio is reset to zero and the method is executed again.

[0025] In some implementations, enabling the vehicle controller to control the electric drive system to exit the operation range prone to failure includes:

[0026] According to the current actual working conditions and the whole vehicle operating environment, the output torque of the electric drive system is appropriately reduced, and the speed of the electric vehicle is reduced under the premise of ensuring safety, so that the electric drive system exits the operating range prone to failure.

[0027] In some implementations, enabling the vehicle controller to control the electric drive system to exit the operating range prone to failure includes:

[0028] For electric vehicles with dual electric drives, part of the torque to be output is proportionally distributed to the other electric drive system according to the current working conditions and the vehicle operating environment, and the electric vehicle is controlled to decelerate under the premise of ensuring safety; for electric vehicles with single electric drive, the electric vehicle is controlled to decelerate under the premise of ensuring safety, so that the electric drive system exits the operating range prone to failure;

[0029] The deceleration rate of the electric vehicle is determined by taking into account actual testing and calibration experience at high speeds, and is determined under the standard of not causing large fluctuations in physical sensation and ensuring that components do not suffer thermal damage.

[0030] According to another aspect of the present invention, there is provided an electric drive system operation control device, the device comprising:

[0031] a feature judgment module, adapted to obtain in real time a feature value of a key feature of an electric drive system that causes a component failure in the electric drive system, and to judge whether the feature value is greater than a preset feature value threshold;

[0032] A time statistics module, adapted to start counting the time during which the component runs when the characteristic value exceeds the characteristic value threshold when the characteristic value is greater than the characteristic value threshold;

[0033] A predetermined value determination module, adapted to obtain a maximum duration predetermined value allowed by the current working condition according to the key feature;

[0034] a ratio comparison module, adapted to calculate and count the ratio of the time to the predetermined value of the maximum duration, and determine whether the ratio is greater than a ratio threshold;

[0035] The warning issuing module is adapted to issue a warning to the vehicle controller when the ratio is equal to or greater than the ratio threshold, so that the vehicle controller controls the electric drive system to exit an operating range prone to failure.

[0036] According to another aspect of the present invention, an electric vehicle is provided, comprising: a processor and a memory arranged to store computer executable instructions, wherein when the executable instructions are executed, the processor executes the electric drive system operation control method according to any one of the above embodiments.

[0037] According to another aspect of the present invention, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores one or more programs, and when the one or more programs are executed by a processor, the electric drive system operation control method according to any one of the above-mentioned methods is implemented.

[0038] From the above, it can be seen that according to the electric drive system operation control method disclosed in the present invention, when the electric vehicle is running at high speed, the torque and speed output of the electric drive system are staged and controlled according to the allowable capacity of the thermally weak components of the electric drive system. Without changing the existing hardware mechanical structure, the maximum output speed capacity of the electric drive system is directly and effectively improved, and the failure prevention and protection of various components in the electric drive system are played. Or, under the premise of equal output capacity, more cost-effective components can be allowed to be used to achieve the purpose of reducing costs and increasing efficiency.

[0039] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0041] Figure 1 A schematic diagram showing a flow chart of an electric drive system operation control method according to some embodiments of the present invention;

[0042] Figure 2 The overall flow chart of the electric drive system operation control method according to some embodiments of the present invention (taking bearings as an example) is shown;

[0043] Figure 3 A schematic diagram showing the structure of an electric drive system operation control device according to some embodiments of the present invention is shown;

[0044] Figure 4 A schematic structural diagram of an electric vehicle (electric drive system controller part) according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0045] The exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to enable the scope of the present invention to be fully communicated to those skilled in the art.

[0046] Figure 1 The flowchart of the electric drive system operation control method according to one embodiment of the present invention is shown. The method can be implemented by a controller software program in the electric drive system of an electric vehicle. The method comprises the following steps:

[0047] Step S110, acquiring in real time a characteristic value of a key characteristic of the electric drive system that causes a component failure in the electric drive system, and determining whether the characteristic value is greater than a preset characteristic value threshold;

[0048] Among them, the components and key features can be analyzed and extracted according to the user's vehicle operation road spectrum, the components that are prone to failure in the high speed range during the full cycle of the electric drive system, which can be one or more components, and the key features that cause the failure of each component, the key features are not limited to speed, torque, high pressure, coolant flow, coolant temperature, component temperature, etc. Specifically, thermal simulation tests and two-wheel drive bench durability tests of various components of the electric drive system can be carried out according to the acquired road spectrum information to obtain the weak feature points in the electric drive system components that are most prone to thermal failure at high speeds;

[0049] Step S120, when the characteristic value is greater than the characteristic value threshold, start counting the time for which the component runs when the characteristic value exceeds the characteristic value threshold;

[0050] According to the control requirements, the running time is generally calculated when the characteristic value of the key characteristic is higher than a threshold, such as the rotation speed is higher than a certain threshold, or the temperature is higher than a certain temperature value, so as to improve the pertinence of the software program analysis control;

[0051] Step S130, obtaining a predetermined maximum duration allowed by the current working condition according to the key feature;

[0052] The maximum duration preset value may be determined based on prior knowledge or based on test conditions of each electric drive system;

[0053] Step S140, calculating and counting the ratio of the time to the predetermined maximum duration, and determining whether the ratio is greater than a ratio threshold;

[0054] The above ratio threshold may be 1 (100%) or a value around 1, or any positive number determined according to actual conditions. A ratio greater than the preset ratio threshold indicates that the component has been operating for a period exceeding the maximum allowed duration in a situation that is unfavorable to the component and prone to failure.

[0055] Step S150, when the ratio is equal to or greater than the ratio threshold, a warning is issued to the vehicle controller so that the vehicle controller controls the electric drive system to exit the operating range where failure is prone to occur.

[0056] Specifically, the software program can send a warning and a vehicle speed control request to the vehicle controller, so that after receiving the warning, the vehicle controller can appropriately reduce the output torque to the electric drive system according to the current actual working conditions and the vehicle operating environment, and decelerate the vehicle at a specific deceleration while ensuring safety, so that the electric drive system can exit the operating range where high-speed and high-torque components are prone to thermal damage.

[0057] The embodiments of the present invention can perform phased control of the torque and speed output of the electric drive system according to the allowable capacity of the thermally weak components of the electric drive system when the electric vehicle is running at high speed, directly and effectively improve the maximum output speed capacity of the electric drive system without changing the existing hardware mechanical structure, and play a role in preventing and protecting the failure of various components in the electric drive system. Or, under the premise of equal output capacity, it can allow the use of more cost-effective components to achieve the purpose of reducing costs and increasing efficiency.

[0058] In some embodiments, in combination Figure 2 As shown, before obtaining the characteristic values ​​of the key characteristics that cause the failure of each component in the electric drive system in step S110, the following steps are included:

[0059] Acquire the speed and torque signal values ​​of the electric drive system in real time;

[0060] According to the speed and the torque signal value, determining whether the current operating condition is in an operating range prone to failure;

[0061] If the current operating condition is in an operating range prone to failure, the method is executed.

[0062] It should be pointed out that, according to tests, in actual operation, the operating range where failure is prone to occur is concentrated in high speed and relatively large torque conditions. Therefore, when the speed of the electric drive system is higher than the speed threshold (for example, the high speed range can be considered as a speed >18000rpm) and the torque is greater than the torque threshold or is at a certain torque level, it can be determined that the electric drive system or the vehicle has entered an operating range where failure is prone to occur.

[0063] In some embodiments, obtaining the predetermined maximum duration allowed by the current working condition according to the key feature in step S130 includes:

[0064] According to the characteristic value of the key characteristic, a table is consulted to obtain a predetermined maximum duration time that the component can maintain operation under the current working condition;

[0065] The table is pre-drawn based on the mechanical properties of the components, the thermal simulation results of the electric drive system, the two-wheel drive bench endurance test results and the whole vehicle test results.

[0066] The table in the embodiment of the present invention is a boundary feature table, which can be selected as the maximum continuous operating time (T1) allowed for different torques and speeds in the high speed range. According to the results of previous thermal simulations and various tests, a list or distribution diagram of the maximum allowable operating times corresponding to multiple operating points in the high speed range is formed.

[0067] Combination Figure 2 Taking the bearing shown in the figure as an example, its maximum duration preset value T1 can be determined based on the mechanical characteristics of the bearing itself, the thermal simulation test of the electric drive system components, the two-wheel drive bench endurance test, and the vehicle test results. At this time, the safe use boundary prone to overheating damage can be expressed as the maximum time boundary value allowed for the bearing to operate at different speeds and torques in the high speed range, as shown in Table 1 below.

[0068] In some embodiments, calculating and counting the ratio of the time to the predetermined maximum duration value, and determining whether the ratio is greater than a ratio threshold value includes:

[0069] There are multiple components, and each component is assigned a weight value, and the sum of the weight values ​​is 1;

[0070] Calculating the product of the ratio of each component and the weight value of the component respectively;

[0071] Calculate the sum of the products, and determine whether the sum is greater than 1;

[0072] The components include bearings, motor shafts, gears, stator windings, rotor magnets or electronic devices.

[0073] This embodiment shows that when there are multiple components, the key features of multiple components can be considered and selected at the same time, and then integrated by setting their weights to obtain the ratio under the comprehensive working condition. For example, the key features may include the speed of the bearing, the speed, temperature or coolant temperature of the motor shaft and gear, the temperature of the stator winding and rotor magnet, the temperature or current of electronic devices, especially power devices, etc. It should be pointed out that when there is only one component, the weight value of the component is 1.

[0074] Specifically, when the components and key features of the components are selected, according to the above steps of the present invention, when the electric drive system enters the operating range where failure is prone to occur at high speed, the software program will obtain the current actual output speed, torque, temperature and other characteristics in real time, and obtain the maximum duration preset value T1 corresponding to each component and key feature of the current call cycle T of the software program by querying the respective maximum duration preset value table corresponding to different working conditions predefined in advance. Optionally, the unit of the call cycle T of the above software program can be selected as millisecond level, for example, the value range of T is 10-100 milliseconds, and T1 generally takes a value of hundreds to thousands of seconds. The value of T1 is specifically shown in Table 1 below. Since T is much smaller than T1, a single software module call cycle T can be used as a statistical unit for judgment, and T / T1 is the unit statistic of the time ratio that is prone to thermal damage under actual working conditions within the call cycle. It should be noted that when there are multiple key features, there may be multiple unit statistics in one call cycle. When running continuously in the high-speed range, the software program continuously performs cumulative calculations of the ratios of various actual operating conditions. When the ratio ∑T / T1 corresponding to the cumulative operating time under different operating conditions in the high-speed operating range where failure is prone to occur exceeds the ratio threshold (for example, 100%), it indicates that the risk of overheating failure is greatly increased. In order to ensure the service life and safety of the components, corresponding deceleration measures such as needing to be taken to limit it.

[0075] In some embodiments, the method further comprises:

[0076] After step S150, the timing starts from when it is determined that the electric drive system exits the operating range prone to failure. When the exit time is greater than a preset time T2, the ratio is cleared and the method is executed again.

[0077] Specifically, when the vehicle runs in a high-speed range and a range prone to thermal failure for a period of time and then exits, if the time of exiting the high-speed range is greater than T2, that is, after the risk of component overheating is eliminated, the accumulated previous thermal damage weight ratio value is cleared, and the weight ratio is recalculated when entering the high-speed range and a range prone to thermal failure again.

[0078] In some embodiments, enabling the vehicle controller to control the electric drive system to exit the operating range prone to failure includes:

[0079] According to the current actual working conditions and the whole vehicle operating environment, the output torque of the electric drive system is appropriately reduced, and the speed of the electric vehicle is reduced under the premise of ensuring safety, so that the electric drive system exits the operating range prone to failure.

[0080] Specifically, when the software program determines that ∑(T / T1)>the ratio threshold, that is, when the electric drive system continues to operate in the high-speed range and the operating conditions and time exceed the predetermined threshold for thermal damage to components, an early warning and a vehicle speed control request are issued to the vehicle controller.

[0081] In some embodiments, enabling the vehicle controller to control the electric drive system to exit the operating range prone to failure includes:

[0082] For electric vehicles with dual electric drives, part of the torque to be output is proportionally distributed to the other electric drive system according to the current working conditions and the vehicle operating environment, and the electric vehicle is controlled to decelerate under the premise of ensuring safety; for electric vehicles with single electric drive, the electric vehicle is controlled to decelerate under the premise of ensuring safety, so that the electric drive system exits the operating range prone to failure;

[0083] The deceleration rate of the electric vehicle is determined by taking into account actual testing and calibration experience at high speeds, and is determined under the standard of not causing large fluctuations in physical sensation and ensuring that components do not suffer thermal damage.

[0084] Combination Figure 3 As shown, another embodiment of the present invention further protects an electric drive system operation control device 300, and the electric drive system operation control device 300 includes:

[0085] The feature judgment module 310 is adapted to obtain in real time a feature value of a key feature of the electric drive system that causes a component failure in the electric drive system, and judge whether the feature value is greater than a preset feature value threshold;

[0086] A time statistics module 320, adapted to start counting the time during which the component operates when the characteristic value exceeds the characteristic value threshold when the characteristic value is greater than the characteristic value threshold;

[0087] A predetermined value determination module 330, adapted to obtain a maximum duration predetermined value allowed by the current operating condition according to the key feature;

[0088] a ratio comparison module 340, adapted to calculate and count the ratio of the time to the predetermined maximum duration, and determine whether the ratio is greater than a ratio threshold;

[0089] The warning issuing module 350 is adapted to issue a warning to the vehicle controller when the ratio is equal to or greater than a ratio threshold, so that the vehicle controller controls the electric drive system to exit an operating range prone to failure.

[0090] According to the electric drive system operation control device disclosed in this embodiment, when the electric vehicle is running at high speed, the torque and speed output of the electric drive system are staged and controlled according to the allowable capacity of the thermally weak components of the electric drive system. The maximum output speed capacity of the electric drive system is directly and effectively improved without changing the existing hardware mechanical structure, and the failure prevention and protection of various components in the electric drive system are played. Alternatively, under the premise of equal output capacity, more cost-effective components can be used to achieve the purpose of reducing costs and increasing efficiency.

[0091] In some embodiments, the feature determination module 310 is further adapted to:

[0092] Acquire the speed and torque signal values ​​of the electric drive system in real time;

[0093] According to the speed and the torque signal value, determining whether the current operating condition is in an operating range prone to failure;

[0094] If the current operating condition is in an operating range prone to failure, the method corresponding to the device is executed.

[0095] In some embodiments, the predetermined value acquisition module 330 is further adapted to:

[0096] According to the characteristic value of the key characteristic, a table is consulted to obtain a predetermined maximum duration time that the component can maintain operation under the current working condition;

[0097] The table is pre-drawn based on the mechanical properties of the components, the thermal simulation results of the electric drive system, the two-wheel drive bench endurance test results and the whole vehicle test results.

[0098] In some embodiments, the ratio comparison module 340 is further adapted to:

[0099] There are multiple components, and each component is assigned a weight value, and the sum of the weight values ​​is 1;

[0100] Calculating the product of the ratio of each component and the weight value of the component respectively;

[0101] Calculate the sum of the products, and determine whether the sum is greater than 1;

[0102] The components include bearings, motor shafts, gears, stator windings, rotor magnets or electronic devices.

[0103] In some embodiments, the device is further adapted to:

[0104] The timing starts from when it is determined that the electric drive system exits the operating range prone to failure. When the exit time is greater than a preset time, the ratio is reset to zero and the method is executed again.

[0105] In some embodiments, the warning issuing module 350 is adapted to:

[0106] According to the current actual working conditions and the whole vehicle operating environment, the output torque of the electric drive system is appropriately reduced, and the speed of the electric vehicle is reduced under the premise of ensuring safety, so that the electric drive system exits the operating range prone to failure.

[0107] In some embodiments, the warning issuing module 350 is specifically adapted to:

[0108] For electric vehicles with dual electric drives, part of the torque to be output is proportionally distributed to the other electric drive system according to the current working conditions and the vehicle operating environment, and the electric vehicle is controlled to decelerate under the premise of ensuring safety; for electric vehicles with single electric drive, the electric vehicle is controlled to decelerate under the premise of ensuring safety, so that the electric drive system exits the operating range prone to failure;

[0109] The deceleration rate of the electric vehicle is determined by taking into account actual testing and calibration experience at high speeds, and is determined under the standard of not causing large fluctuations in physical sensation and ensuring that components do not suffer thermal damage.

[0110] It should be noted that the specific implementation of the above-mentioned device embodiments can be carried out with reference to the specific implementation of the above-mentioned corresponding method embodiments, which will not be repeated here. Specific embodiments

[0112] The following schematic description is given using the bearing components in the electric drive system as an example:

[0113] Under specific working conditions, the continuous operation time boundaries T1 and T2 for bearings to be prone to overheating damage and eliminate overheating risks can be determined based on the results of the bearing's own mechanical characteristics, thermal simulation of electric drive system components, two-wheel drive bench endurance test, and vehicle test. The safe use boundary for overheating damage can be expressed as the maximum time boundary value allowed for the bearing to operate at different speeds and torques in the high speed range. The boundary value can be shown in the following schematic illustration table:

[0114] Table 1

[0115]

[0116] Combination Figure 2 As shown, the high speed software control strategy of the electric drive system is as follows:

[0117] Step 1: Receive the vehicle motor output speed and torque signal in real time.

[0118] Step 2: Determine whether the electric drive system is running in a high speed range (as shown in the table above, the high speed range can be considered as a speed > 18000rpm). If so, go to Step 3; if not, return to Step 1.

[0119] Step 3: When the operating point enters the high speed range, the operating condition information within the current software program call cycle is obtained in real time, and the corresponding maximum allowable running time under different operating conditions defined in the early stage is interpolated and looked up in the table to obtain the maximum duration predetermined value T1 allowed for the actual operating point within the current software program call cycle T.

[0120] Step 4: Calculate the weight of the actual working conditions in the current software module call cycle for the final thermal damage to the components based on the maximum allowable time obtained in Step 3. The calculation method can be, but is not limited to, the following method: software module call cycle / predetermined maximum safe time allowed for continuous operation, that is, T / T1.

[0121] Step 5: The weight ratio calculated in Step 4 is cumulatively calculated in each software module calling cycle, and the calculated value is ∑(T / T1).

[0122] Step 6: If the operating condition exits the high speed range and the operating range prone to thermal damage after a period of time T2 during the cumulative calculation of weights, it means that the risk of mechanical parts being easily damaged by overheating is eliminated, and the cumulatively calculated weight ratio ∑(T / T1) is cleared. If the continuously accumulated weight value is greater than the threshold, that is, ∑(T / T1)>1, the software sends component thermal damage warning information and vehicle speed torque control request to the vehicle controller.

[0123] Step 7: The vehicle controller responds to the speed limit and torque limit request, and controls the torque demand of the motor system and the speed of the vehicle. The specific method can be: For dual-electric drive vehicles, part of the torque to be output can be allocated to the other electric drive in a certain proportion according to the current actual working conditions and the vehicle operating environment, and the vehicle is decelerated at a specific deceleration under the premise of ensuring safety, so that the electric drive system exits the operating range where high-speed and high-torque components are prone to thermal damage. For single-electric drive vehicles, the vehicle speed is controlled at a specific deceleration under the premise of ensuring safety, so that the electric drive system exits the operating range where high-speed and high-torque components are prone to thermal damage. The specific deceleration when controlling the vehicle speed is obtained through actual testing and calibration experience at high speed of the vehicle, and is determined by comprehensive consideration under the standard of not generating large somatic fluctuations and ensuring that the electric drive components do not cause thermal damage.

[0124] Step 8: After the electric drive system exits the operating range prone to thermal damage for a period of time T2, the risk of mechanical parts being easily damaged by overheating is eliminated, and the cumulatively calculated weighted value ∑(T / T1) is reset to zero. The system can once again have the ability to operate at high speed and high torque, and the software re-accumulates and makes judgments.

[0125] It should be noted that:

[0126] The algorithm and display provided herein are not inherently related to any particular computer, virtual device or other equipment. Various general-purpose devices can also be used together with the teachings based on this. According to the above description, it is obvious to construct the structure required for this type of device. In addition, the present invention is not directed to any specific programming language either. It should be understood that various programming languages ​​can be utilized to realize the content of the present invention described herein, and the description of the above specific language is for the purpose of disclosing the best mode of the present invention.

[0127] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0128] Similarly, it should be understood that in order to streamline the present invention and aid in understanding one or more of the various inventive aspects, in the above description of exemplary embodiments of the present invention, various features of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof. However, this method of disclosure should not be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim.

[0129] Those skilled in the art will appreciate that the modules in the devices in the embodiments may be adaptively changed and arranged in one or more devices different from the embodiments. The modules or units or components in the embodiments may be combined into one module or unit or component, and in addition they may be divided into a plurality of submodules or subunits or subcomponents. Except that at least some of such features and / or processes or units are mutually exclusive, all features disclosed in this specification (including the accompanying claims, abstracts and drawings) and all processes or units of any method or device disclosed in this manner may be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstracts and drawings) may be replaced by an alternative feature providing the same, equivalent or similar purpose.

[0130] Furthermore, those skilled in the art will appreciate that although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features from different embodiments is meant to be within the scope of the present invention and to form different embodiments.

[0131] The various component embodiments of the present invention may be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. It should be understood by those skilled in the art that a microprocessor or a digital signal processor (DSP) may be used in practice to implement some or all of the functions of some or all of the components in the electric drive system operation control device according to an embodiment of the present invention. The present invention may also be implemented as a device or device program (e.g., a computer program and a computer program product) for executing part or all of the methods described herein. Such a program for implementing the present invention may be stored on a computer-readable medium, or may be in the form of one or more signals. Such a signal may be downloaded from an Internet website, or provided on a carrier signal, or provided in any other form.

[0132] An embodiment of the present invention provides a non-volatile computer storage medium, wherein the computer storage medium stores at least one executable instruction, and the computer executable instruction can execute the above-mentioned electric drive system operation control method in any of the above-mentioned method embodiments.

[0133] Figure 4 The schematic diagram of the structure of an embodiment of an electric vehicle (electric drive controller) of the present invention is shown. The specific embodiment of the present invention does not limit the specific structure of the electric vehicle.

[0134] like Figure 4 As shown, the electric vehicle (electric drive controller) may include: a processor (processor) 402 , a communications interface (Communications Interface) 404 , a memory (memory) 406 , and a communication bus 408 .

[0135] Wherein: the processor 402, the communication interface 404, and the memory 406 communicate with each other through the communication bus 408. The communication interface 404 is used to communicate with other devices such as a client or other server network elements. The processor 402 is used to execute the program 410, which can specifically execute the relevant steps in the above-mentioned electric drive system operation control method embodiment for an electric vehicle.

[0136] Specifically, the program 410 may include program codes, which include computer operation instructions.

[0137] The processor 402 may be a central processing unit (CPU), or an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present invention. The one or more processors included in the electric vehicle may be processors of the same type, such as one or more CPUs; or processors of different types, such as one or more CPUs and one or more ASICs.

[0138] The memory 406 is used to store the program 410. The memory 406 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0139] The program 410 can be specifically used to enable the processor 402 to execute operations corresponding to the above-mentioned electric drive system operation control method embodiment.

[0140] It should be noted that the above embodiments illustrate the present invention rather than limit it, and that those skilled in the art may devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference symbol between brackets shall not be construed as a limitation on the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "one" or "an" preceding an element does not exclude the presence of a plurality of such elements. The present invention may be implemented by means of hardware comprising a number of different elements and by means of a suitably programmed computer. In a unit claim enumerating a number of devices, several of these devices may be embodied by the same hardware item. The use of the words first, second, and third, etc., does not indicate any order. These words may be interpreted as names.

Claims

1. A method for controlling the operation of an electric drive system, characterized in that: The method comprises: Acquire in real time a characteristic value of a key characteristic of an electric drive system that causes a component failure in the electric drive system, and determine whether the characteristic value is greater than a preset characteristic value threshold; When the characteristic value is greater than the characteristic value threshold, start counting the time for which the component runs when the characteristic value exceeds the characteristic value threshold; According to the key feature, a predetermined maximum duration allowed by the current working condition is obtained; Calculate and count the ratio of the time to the predetermined maximum duration value, and determine whether the ratio is greater than a ratio threshold; When the ratio is equal to or greater than the ratio threshold, an early warning is issued to the vehicle controller so that the vehicle controller controls the electric drive system to exit the operating range where failure is prone to occur.

2. The method according to claim 1, characterized in that The process of obtaining the characteristic values ​​of the key characteristics that cause the failure of each component in the electric drive system includes: Acquire the speed and torque signal values ​​of the electric drive system in real time; According to the speed and the torque signal value, determining whether the current operating condition is in an operating range prone to failure; If the current operating condition is in an operating range prone to failure, the method is executed.

3. The method according to claim 1, characterized in that: Acquiring a predetermined maximum duration value allowed by the current working condition according to the key features includes: According to the characteristic value of the key characteristic, a table is consulted to obtain a predetermined maximum duration time that the component can maintain operation under the current working condition; The table is pre-drawn based on the mechanical properties of the components, thermal simulation results of the electric drive system, two-wheel drive bench endurance test results and / or vehicle test results.

4. The method according to claim 1, characterized in that Calculating and counting the ratio of the time to the predetermined maximum duration value, and determining whether the ratio is greater than a ratio threshold value includes: There are multiple components, and each component is assigned a weight value, and the sum of the weight values ​​is 1; Calculating the product of the ratio of each component and the weight value of the component respectively; Calculate the sum of the products, and determine whether the sum is greater than 1; The components include bearings, motor shafts, gears, stator windings, rotor magnets or electronic devices.

5. The method according to any one of claims 1 to 4, characterized in that The method further comprises: The timing starts from when it is determined that the electric drive system exits the operating range prone to failure. When the exit time is greater than a preset time, the ratio is reset to zero and the method is executed again.

6. The method according to any one of claims 1 to 4, characterized in that The vehicle controller controls the electric drive system to exit the operation range prone to failure, including: According to the current actual working conditions and the whole vehicle operating environment, the output torque of the electric drive system is appropriately reduced, and the speed of the electric vehicle is reduced under the premise of ensuring safety, so that the electric drive system exits the operating range prone to failure.

7. The method according to claim 6, characterized in that The vehicle controller controls the electric drive system to exit the operation range prone to failure, including: For electric vehicles with dual electric drives, part of the torque to be output is proportionally distributed to the other electric drive system according to the current working conditions and the vehicle operating environment, and the electric vehicle is controlled to decelerate under the premise of ensuring safety; for electric vehicles with single electric drive, the electric vehicle is controlled to decelerate under the premise of ensuring safety, so that the electric drive system exits the operating range prone to failure; Among them, the deceleration rate of controlling the deceleration of the electric vehicle is comprehensively determined by considering the actual test and calibration experience of the whole vehicle at high speed, under the standard of not generating large fluctuations in physical sensation and ensuring that the components do not suffer thermal damage.

8. An electric drive system operation control device, characterized in that: The device comprises: a feature judgment module, adapted to obtain in real time a feature value of a key feature of an electric drive system that causes a component failure in the electric drive system, and to judge whether the feature value is greater than a preset feature value threshold; A time statistics module, adapted to start counting the time during which the component runs when the characteristic value exceeds the characteristic value threshold when the characteristic value is greater than the characteristic value threshold; A predetermined value determination module, adapted to obtain a maximum duration predetermined value allowed by the current working condition according to the key feature; a ratio comparison module, adapted to calculate and count the ratio of the time to the predetermined value of the maximum duration, and determine whether the ratio is greater than a ratio threshold; The warning issuing module is adapted to issue a warning to the vehicle controller when the ratio is equal to or greater than the ratio threshold, so that the vehicle controller controls the electric drive system to exit an operating range prone to failure.

9. An electric vehicle, characterized in that: The system comprises a processor and a memory arranged to store computer executable instructions, wherein when the executable instructions are executed, the processor executes the electric drive system operation control method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores one or more programs, and when the one or more programs are executed by the processor, the electric drive system operation control method according to any one of claims 1-7 is implemented.

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