Control system and method for mitigating driveline torque spikes in an electric vehicle

Abstract

A control system and method for mitigating driveline torque spikes in an electric vehicle are contemplated. These driveline torque spikes can be mitigated with a motor spike torque command that is generated in response to a wheel acceleration of a wheel of the vehicle exceeding a spike threshold. The motor spike torque command can be structured for controlling an electric motor of the vehicle to mitigate a driveline torque spike in a driveline structured to connect the motor to the wheel.

Description

Technical Field

[0001] introduction

[0002] This disclosure relates to control systems and methods for mitigating transmission torque spikes when an electric vehicle experiences relatively sudden changes in operating conditions, such as in response to the vehicle traveling between surfaces with different coefficients of friction. Background Technology

[0003] Electric vehicles typically rely on some type of drivetrain to transfer rotational force from an electric motor to one or more wheels. Electric vehicles travel across a variety of surfaces and periodically experience drivetrain torque spikes when crossing boundaries between surfaces with different coefficients of friction (e.g., when crossing between a low-friction surface and a high-friction surface, or vice versa). Torque spikes associated with crossing boundaries between different surfaces can originate from wheel slippage, inducing a sudden imbalance in the relative relationship of rotational forces acting on each of the motor and wheels. When crossing a boundary from a low-friction surface to a high-friction surface, such a torque spike can be caused by a rapid decrease in wheel speed, and vice versa, when crossing a boundary from a high-friction surface to a low-friction surface, such a torque spike can be caused by a rapid increase in wheel speed. Similar torque spikes can be associated with panic break events, which occur when a vehicle operator engages the braking system in such a manner that the wheel speed drops abruptly and drastically. Summary of the Invention

[0004] This paper discloses a control system and method for mitigating drivetrain torque spikes in electric vehicles. The ability to mitigate drivetrain torque spikes can be beneficial in limiting undesirable strains in the drivetrain and other mechanisms when the vehicle traverses a boundary between surfaces with different coefficients of friction, experiences panic damage, and / or otherwise undergoes events that cause wheel slippage or other rapid changes in wheel speed.

[0005] One aspect of this disclosure relates to a control system for an electric vehicle. The system may include: a motor controller configured to control a motor of the vehicle according to one or more of a plurality of torque commands; and a motor spike controller configured to generate a motor spike torque command as one of the plurality of torque commands. The motor spike torque command may be configured to mitigate transmission torque spikes in a drivetrain configured to connect the motor to the wheels of the vehicle.

[0006] The system may include a motor spike controller configured to generate motor spike torque commands based on a torque spike equation. The torque spike equation can be expressed as:

[0007]

[0008] Among them, T m It is the motor peak torque command, J m It is the motor inertia. Ratio is the wheel acceleration of the wheel, and Ratio is a constant representing the speed ratio between the motor and the one or more driven wheels.

[0009] The system may include a motor spike controller configured to generate a motor spike torque command in response to an ice clunk event occurring as a vehicle crosses from a first surface to a second surface. The first surface may have a first frictional force and the second surface may have a second frictional force, which differs from the first frictional force by a predetermined amount.

[0010] The system may include a motor spike controller configured to generate a motor spike torque command in response to a panic braking event that occurs due to wheel deceleration caused by brakes on the vehicle exceeding a predetermined rate.

[0011] The system may include a motor spike controller configured to generate motor spike torque commands as feedforward control.

[0012] One aspect of this disclosure relates to a control method for mitigating transmission torque spikes in an electric vehicle. The method may include generating a motor spike torque command in response to a wheel acceleration exceeding a spike threshold. The motor spike torque command may be configured to control the vehicle's electric motor to mitigate transmission torque spikes in the transmission system, which is configured to connect the motor to the wheel.

[0013] This method may include: generating a motor peak torque command based on a torque peak equation. The torque peak equation can be expressed as:

[0014]

[0015] Among them, T m It is the motor peak torque command, J m It is the motor inertia. Ratio is the wheel acceleration of the wheel, and Ratio is a constant representing the speed ratio between the motor and the one or more driven wheels.

[0016] The method may include generating a wheel slip torque command based on the wheel speed measured at the wheel. The wheel slip torque command may be configured to control the motor to mitigate wheel slip.

[0017] The method may include generating a wheelflare torque command based on the transmission output speed of the transmission, which is included as part of the drivetrain. The wheelflare torque command may be configured to control a motor to mitigate wheel flare.

[0018] The method may include: the motor controller being configured to arbitrate between commanding the motor according to one of a motor peak torque command, a wheel slip torque command, and a wheel spread torque.

[0019] The method may include: a wheel slip controller configured to generate a wheel slip torque command, a wheel spread controller configured to generate a wheel spread torque command, and a motor spike controller configured to generate a motor spike torque command.

[0020] The method may include: the motor spike controller generating a motor spike torque command in response to a wheel speed greater than a wheel speed threshold or a transmission output greater than a predetermined output acceleration threshold.

[0021] The method may include: generating a motor peak torque command as a feedforward control.

[0022] The method may include generating each of a wheel slip torque command and a wheel spread torque command as feedback control.

[0023] The method may include: generating a motor peak torque command that matches the motor inertia with the wheel inertia in terms of speed.

[0024] The method may include: generating a motor peak torque command to control the motor speed to be close to the wheel speed.

[0025] One aspect of this disclosure relates to a control system for an electric vehicle. The system may include: a wheel slip controller configured to control wheel slip based on wheel speeds measured at the wheels of the vehicle; a wheel flare controller configured to control wheel flare based on a transmission output speed, the transmission being included as part of the vehicle's drivetrain; and a motor spike controller configured to control drivetrain torque spikes based on wheel acceleration and motor inertia of a motor connected to the wheel via the drivetrain.

[0026] The system may include a motor spike controller configured to generate motor spike torque commands for controlling the motor to mitigate transmission torque spikes.

[0027] The system may include a motor spike controller configured to generate motor spike torque commands based on a torque spike equation. The torque spike equation can be expressed as:

[0028]

[0029] Among them, T m It is the motor peak torque command, J m It is the motor inertia. Ratio is the wheel acceleration of the wheel, and Ratio is a constant representing the speed ratio between the motor and the one or more driven wheels.

[0030] The system may include a motor controller configured to arbitrate between motors using a wheel slip controller, a wheel spread controller, and a motor spike controller.

[0031] The present invention also discloses the following technical solutions:

[0032] 1. A control system for an electric vehicle, the system comprising:

[0033] A motor controller configured to control the vehicle's motor according to one or more of a plurality of torque commands; and

[0034] A motor spike controller is configured to generate a motor spike torque command as one of the plurality of torque commands, the motor spike torque command being configured to mitigate transmission torque spikes in the transmission system, the transmission system being configured to connect the motor to the wheels of the vehicle.

[0035] 2. The system according to technical solution 1, wherein the motor spike controller is configured to generate the motor spike torque command according to the torque spike equation, the torque spike equation being expressed as:

[0036]

[0037] Among them, T m It is the peak torque command of the motor, J m It is the motor inertia of the motor. Ratio is the wheel acceleration of the wheel, and Ratio is a constant representing the speed ratio between the motor and the wheel.

[0038] 3. The system according to technical solution 2, wherein the motor spike controller is configured to generate the motor spike torque command in response to an ice impact event caused by the vehicle crossing from a first surface to a second surface, the first surface having a first frictional force and the second surface having a second frictional force, the second frictional force differing from the first frictional force by a predetermined amount.

[0039] 4. The system according to technical solution 2, wherein the motor spike controller is configured to generate the motor spike torque command in response to a panic braking event caused by the brakes on the vehicle causing the wheel speed to decelerate faster than a predetermined rate.

[0040] 5. The system according to technical solution 2, wherein the motor spike controller is configured to generate the motor spike torque command as feedforward control.

[0041] 6. A control method for mitigating torque spikes in the drivetrain of an electric vehicle, the method comprising:

[0042] A motor peak torque command is generated in response to a wheel acceleration exceeding a peak threshold of the vehicle's wheels. The motor peak torque command is configured to control the vehicle's electric motor to mitigate the drivetrain torque peak in the drivetrain, which is configured to connect the motor to the wheels.

[0043] 7. The method according to technical solution 6 further includes: generating the motor peak torque command based on a torque peak equation, wherein the torque peak equation is expressed as:

[0044]

[0045] Among them, T m It is the peak torque command of the motor, J m It is the motor inertia of the motor. Ratio is the wheel acceleration of the wheel, and Ratio is a constant representing the speed ratio between the motor and the wheel.

[0046] 8. The method according to technical solution 7, further comprising: generating a wheel slip torque command based on a wheel speed measured at the wheel, the wheel slip torque command being configured to control the motor to alleviate wheel slip.

[0047] 9. The method according to technical solution 8, further comprising: generating a wheel flare torque command based on a transmission output speed of a transmission, the transmission being included as part of the drivetrain, the wheel flare torque command being configured to control the motor to mitigate wheel flare.

[0048] 10. The method according to technical solution 9, further comprising: the motor controller being configured to arbitrate between commanding the motor according to one of the motor peak torque command, the wheel slip torque command, and the wheel spread torque.

[0049] 11. The method according to technical solution 10, further comprising: a wheel slip controller configured to generate a wheel slip torque command, a wheel spread controller configured to generate a wheel spread torque command, and a motor spike controller configured to generate the motor spike torque command.

[0050] 12. The method according to technical solution 11 further includes: the motor peak controller generating the motor peak torque command in response to the wheel speed being greater than a wheel speed threshold or the output of the transmission being greater than a predetermined output acceleration threshold.

[0051] 13. The method according to technical solution 12 further includes: generating the motor peak torque command as feedforward control.

[0052] 14. The method according to technical solution 13 further includes: generating each of the wheel slip torque command and the wheel spread torque command as feedback control.

[0053] 15. The method according to technical solution 6 further includes: generating the motor peak torque command such that the motor inertia of the motor matches the wheel inertia in speed.

[0054] 16. The method according to technical solution 6 further includes: generating a peak torque command for the motor to control the motor speed to be close to the wheel speed of the wheel.

[0055] 17. A control system for an electric vehicle, the system comprising:

[0056] A wheel slip controller is configured to control wheel slip based on the wheel speed measured at the wheels of the vehicle.

[0057] A wheel flare controller configured to control wheel flare based on the output speed of a transmission, the transmission being included as part of the vehicle's drivetrain; and

[0058] A motor spike controller is configured to control transmission torque spikes based on the wheel acceleration of the wheel and the motor inertia of the motor connected to the wheel via the transmission system.

[0059] 18. The system according to technical solution 17, wherein the motor spike controller is configured to generate motor spike torque commands for controlling the motor to mitigate torque spikes in the transmission system.

[0060] 19. The system according to technical solution 18, wherein the motor spike controller is configured to generate the motor spike torque command according to the torque spike equation, the torque spike equation being expressed as:

[0061]

[0062] Among them, T m It is the peak torque command of the motor, J m It is the motor inertia of the motor. It is the wheel acceleration, and Ratio is a constant representing the speed ratio between the motor and the wheel.

[0063] 20. The system according to claim 19 further includes a motor controller configured to arbitrate between the motors using the wheel slip controller, the wheel spread controller, and the motor spike controller. Attached Figure Description

[0064] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0065] Figure 1 The illustration shows a schematic diagram of a hybrid electric vehicle according to a non-limiting aspect of the present disclosure, the hybrid electric vehicle having a control system for mitigating torque spikes in the drivetrain.

[0066] Figure 2 The diagram illustrates a flowchart of a control method for mitigating torque spikes in a powertrain of an electric vehicle, according to a non-limiting aspect of this disclosure.

[0067] The above-described features and advantages of this teaching, as well as other features and advantages, will readily become apparent from the following detailed description of the modes of implementation of this teaching when understood in conjunction with the accompanying drawings. It should be understood that even though embodiments may be described individually in the following drawings, their individual features may be combined into additional embodiments. Detailed Implementation

[0068] Detailed embodiments of the present disclosure are disclosed herein as needed; however, it will be understood that the disclosed embodiments are merely exemplary embodiments of the present disclosure and may be embodied in various and alternative forms. The drawings are not necessarily drawn to scale; some features may be exaggerated or minimized to show detail of particular components. Therefore, the specific structural and functional details disclosed herein are not to be construed as limiting, but merely as an illustrative basis for teaching those skilled in the art to employ the present disclosure in various ways.

[0069] Figure 1A schematic diagram of a hybrid electric vehicle 10 according to a non-limiting aspect of the present disclosure is illustrated, the hybrid electric vehicle having a control system 12 for mitigating torque spikes in the drivetrain. For illustrative and non-limiting purposes, vehicle 10 is illustrated as a hybrid of an internal combustion engine (ICE) 14 and an electric motor 16 to cooperatively provide rotational force / torque to one or more of a plurality of wheels 20, 22, 24, 26. Vehicle 10 is shown to include a drivetrain 30 configured to connect the ICE 14 and the motor 16 to the front wheels 20, 24. Drivetrain 30 may include a transmission 34, a driveshaft 36, a differential 38, axles 40, 42 and / or other components to facilitate the transmission of rotational force from the ICE 14 and / or the motor 16 to the wheels 20, 22, 24, 26. For illustrative and non-limiting purposes, vehicle 10 is primarily described as a two-wheel drive vehicle, as the present disclosure fully contemplates its use and application with four-wheel drive vehicles and other non-automotive types of vehicles.

[0070] Motor controller 46 may be configured to generate control signals associated with and to direct, and otherwise implement, desired control of ICE 14 and / or motor 16. One or more battery packs 50 may be configured to supply DC power to a DC-AC inverter 52, which then supplies AC power to electric motor 16 as directed by motor controller 46. For illustrative purposes, vehicle 10 is shown as including ICE 14, as this disclosure fully contemplates its use and application with battery-only vehicles (i.e., vehicles that rely solely on motor 16 for propulsion). Motor controller 46 may be considered as a motor controller unit (MCU), a main controller, an engine control unit (ECU), and / or other types of controllers configured to facilitate the control of several vehicle operations according to the processes contemplated herein.

[0071] The motor controller 46 may be configured to interact directly and / or via a vehicle network or bus with vehicle components to facilitate the exchange of information, data, commands, etc., with systems, sensors, and other elements within the vehicle 10. One non-limiting aspect of this disclosure contemplates that the motor controller 46 is configured to interact with or include, additional controllers 56, 58, 60. Controllers 46, 56, 58, 60 may be functional constructs associated with activities resulting from the execution of multiple non-transitory instructions stored on a computer-readable storage medium by one or more processors. For example, the operation, process, command, function, etc., of each controller 46, 56, 58, 60 may be defined according to individual non-transitory instructions associated with it. Therefore, for non-limiting purposes, controllers 46, 56, 58, 60 are presented separately to characterize the contemplated control functions.

[0072] Motor controller 46 may be the final arbiter of torque commands for controlling ICE 14 and / or motor 16. These torque commands may be instructions or other information provided by motor controller 46 to guide the propulsion of vehicle 10. While the contemplated control may be implemented in conjunction with the use of ICE 14, this disclosure is primarily described as follows: motor controller 46 arbitrates various torque commands among controllers 56, 58, 60 to select one or more torque commands to control the operation of motor 16, which may occur independently of or in cooperation with ICE 14. In this exemplary case, controller 56 may be a wheel slip controller configured to generate wheel slip torque commands, controller 58 may be a wheel spreader controller configured to generate wheel spread torque commands, and controller 60 may be a motor spike controller configured to generate motor spike torque commands. The motor controller 46 may be assigned the following tasks: to arbitrate one or more of the wheel slip torque command, the wheel outward torque command, and the motor peak torque command, in order to guide the operation of the motor 16 and / or other components associated therewith, such as the battery 50, the inverter 52, etc.

[0073] The wheel slip controller 56 and wheel flare controller 58 can be closed-loop controllers configured to facilitate the generation of corresponding torque commands. The wheel slip controller 56 and wheel flare controller 58 can generally be characterized as control functions focused on preventing slippage of wheels 20, 22, 24, and 26, i.e., maximizing the traction between wheels 20, 22, 24, and 26 and the travel surface. The wheel slip torque command generated by the wheel slip controller 56 can be based on wheel speeds measured at one or more of wheels 20, 22, 24, and 26, and is configured to control motor 16 to mitigate wheel slippage. The wheel flare torque command generated by the wheel flare controller 58 can be based on the transmission output speed of transmission 34, and is configured to control motor 16 to mitigate wheel flare of wheels 20, 22, 24, and 26.

[0074] The motor spike controller 60 can be an open-loop controller configured to generate a motor spike torque command as a feedforward type command. The feedforward nature of the motor spike controller 60 can be advantageous in providing a faster response to wheel slip and / or a response independent of feedback-type loops than the wheel slip controller 56 and wheel flare controller 58, allowing for rapid implementation. A non-limiting aspect of this disclosure envisions the motor spike controller 60 being configured to mitigate transmission torque spikes within the transmission system 30. Transmission torque spikes can occur under various conditions and are generally considered temporary or transient events, thereby enabling a rapid response that can benefit the limitation of strain on the transmission system 30 or other systems of the vehicle 10.

[0075] Drivetrain torque spikes can occur, for example, in response to an ice impact event or when the vehicle 10 crosses a boundary between surfaces with a predetermined difference in friction coefficients. When crossing a boundary from a low-friction surface to a high-friction surface, a drivetrain torque spike can be caused by a rapid decrease in wheel speed, and vice versa; when crossing a boundary from a high-friction surface to a low-friction surface, a drivetrain torque spike can be caused by a rapid increase in wheel speed. Drivetrain torque spikes can also occur due to panic-induced disruption events (when a vehicle operator engages the braking system in such a manner that wheel speed suddenly and abruptly decreases faster than a predetermined rate). Drivetrain torque spikes can be considered as an imbalance between the motor 16 and the driven wheels 20, 24 associated with the motor 16 and / or as the driven wheels 20, 24 operating in a manner that violates the speed ratios, gear ratios, and / or other design ratios desired for typical operation of the drivetrain 30.

[0076] To limit the effects of imbalance and / or mitigate the amount of torque spikes, a non-limiting aspect of this disclosure envisions a motor spike controller 60 generating a motor spike torque command in a manner sufficient to use the motor 16 as an actuator, thereby enabling the actuator to effectively impart energy / force to or expend energy / force from the drivetrain 30 to mitigate torque spikes. Optionally, the motor spike torque command can be used in such a manner that the inertia of the motor 16 is matched with the inertia of the driven wheels 20, 24, and / or the speed of the motor 16 is matched with the speed of the driven wheels 20, 24, such that both (motor and wheels) rotate at substantially the same pace. Matching can take into account component portions of the drivetrain 30, i.e., the ratios and gear drives associated with the transmission 34, driveshaft 36, differential 38, etc. A motor peak torque command can be generated to attempt to quickly counteract or limit shaft torsion of drive shaft 36 and axles 40, 42, so that those and other components of drivetrain 30 can be rebalanced to a state prior to the torque peak event.

[0077] A motor peak torque command can be implemented to better balance torsional forces, thereby attempting to rapidly improve the differences between the driven wheels 20, 24 and the motor 16 caused by torque peak events. One non-limiting aspect of this disclosure contemplates generating a motor peak torque command based on a torque peak equation. The torque peak equation can be expressed as:

[0078]

[0079] Among them, T m It is the motor peak torque command, J m It is the motor inertia. This refers to the wheel acceleration, and Ratio is a constant representing the speed ratio between the motor 16 and the one or more driven wheels 20, 24. Motor inertia (J) m The wheel acceleration () can be a physical value or constant associated with the material properties, sizing, and other design characteristics of the motor 16. The speed ratio can be a calculated value based on a wheel speed sensor that assesses the rate of change at one of the driven wheels 20, 24, such as a rate of change associated with a sudden increase or decrease in wheel speed due to ice impact, panic braking, different friction surfaces, etc. The speed ratio can be a physical value or constant associated with the material properties, dimensional determination, and other design characteristics of the transmission system 30, such as a value derived from gear transmission, step-down, mechanical advantages, etc., associated with interconnecting the wheels 20, 24 with the motor 16.

[0080] Figure 2 A flowchart 70 of a control method for mitigating drivetrain torque spikes in an electric vehicle, according to a non-limiting aspect of this disclosure, is illustrated. This method can improve the operation of an electric vehicle by mitigating drivetrain torque spikes and thereby reducing undesirable strains in the drivetrain and other mechanisms, such as when the vehicle traverses a boundary between surfaces with different coefficients of friction, experiences panic attacks, and / or otherwise undergoes events that cause wheel slippage or other rapid changes in wheel speed. A controller can be used to facilitate this method, as well as associated operations, processes, functions, commands, etc., having a corresponding set of non-transitory instructions stored on a computer-readable storage medium, such that, when executed using a processor, these non-transitory instructions are sufficient to facilitate mitigation of drivetrain torque spikes in the manner contemplated herein, i.e., by generating motor spike torque commands for use by a motor controller to control the motor to mitigate drivetrain torque spikes.

[0081] Block 72 relates to initiating the contemplated control strategy and method. This may include: a motor controller or other vehicle controller initiating its operation or otherwise collecting data according to a process required to identify various vehicle operating states and associated operator needs. One non-limiting aspect of this disclosure contemplates implementing the method based on wheel slip control and wheel flare control, such that the initialization process may include: the motor controller initializing each of the wheel slip controller, wheel flare controller, and motor spike controller to generate a wheel slip torque command, a wheel flare torque command, and a motor spike torque command, respectively. The motor controller may be configured to receive each of these torque commands and arbitrate the corresponding control of the motor, i.e., select one or more of these torque commands for controlling the motor and / or associated components (e.g., battery, inverter, etc.).

[0082] Block 74 relates to determining whether either the wheel slip controller and / or the wheel spreader controller is actively involved in generating wheel slip torque commands and / or wheel spreader torque commands, respectively. This assessment can be useful for identifying conditions or events that cause the vehicle to begin experiencing wheel slip, or conditions that are likely or likely to occur in the near future (e.g., when wheel speed exceeds a wheel speed threshold or transmission output exceeds a predetermined output acceleration threshold). Integrating the generation of motor spike torque commands with the torque commands of the wheel slip controller and the wheel spreader controller can help limit the programming and other processing associated with their implementation. In other words, rather than programming or otherwise generating procedures for detecting events preceding torque spike events or performing independent measurements, the motor spike controller can more simply identify this need from the binary flags set for the wheel slip controller and the wheel spreader controller. Alternatively, the generation of motor spike torque commands can be permanently generated throughout vehicle operation and continuously provided to the motor controller. This can help improve the time delay associated with triggering the generation of motor spike torque commands and delivering them to the motor controller. The motor controller can be configured accordingly to ignore peak torque commands from the motor until conditions indicate that they need to be used.

[0083] Block 76 relates to calculating the wheel acceleration of one or more of the motor-driven wheels. The wheel acceleration may be based on the wheel speed measured using sensors located on the corresponding wheel, such as sensors associated with the anti-lock braking system (ABS).

[0084] Block 78 relates to determining whether the wheel acceleration exceeds a predefined motor peak threshold. The motor peak threshold may be a design parameter set based on the possible occurrence of drivetrain torque peaks. The wheel acceleration threshold may, for example, be specified with sufficient margin such that the motor peak threshold is less than the threshold that would actually induce a drivetrain torque peak. The motor peak threshold may be calculated as an absolute value such that it can be exceeded given a sufficient amount of acceleration or deceleration. The use of the wheel acceleration threshold can be beneficial for comparison with wheel speed thresholds or transmission speed thresholds (i.e., thresholds utilized by the wheel slip controller and wheel spread controller), as acceleration is a more accurate representation of drivetrain torque peaks or conditions that are likely to cause axle twist.

[0085] Block 80 involves generating a motor peak torque command based on the torque peak equation. The torque peak equation can be expressed as:

[0086]

[0087] Among them, T m It is the motor peak torque command, J m It is the motor inertia. This refers to the wheel acceleration, and Ratio is a constant representing the speed ratio between the motor and the one or more driven wheels. Motor inertia (J) m Wheel acceleration () can be a physical value or constant associated with the material properties, dimensional determination, and other design characteristics of the motor. The speed ratio can be a calculated value from a wheel speed sensor based on the rate of change at one of the driven wheels, such as a rate of change associated with a sudden increase or decrease in wheel speed due to ice impact, panic braking, different friction surfaces, etc. The speed ratio can be a physical value or constant associated with the material properties, dimensional determination, and other design characteristics of the drivetrain.

[0088] This disclosure may be embodied in many different forms. Indicative examples are shown in the various figures and described in detail herein as non-limiting representations of the disclosed principles. For that purpose, elements and limitations not expressly set forth in the foregoing but in the appended claims should not be incorporated into the claims individually or collectively by implication, inference, or otherwise. Furthermore, unless expressly waived, the use of the singular includes the plural, and vice versa; the terms “and” and “or” should both be connected and separate; “any” and “all” should both mean “any and all”; and the words “comprising,” “containing,” “including,” “having,” etc., should mean “including, but not limited to.” The terms “comprising,” “including,” and “having” are inclusive and therefore specify the presence of the stated features, steps, operations, elements, or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, or components. The order of steps, processes, and operations may be changed where possible, and additional or alternative steps may be employed. As used herein, the term “or” includes any and all combinations of the associated listed items. The term “any one of” is understood to include any possible combination of the referenced items, including “any one of” the referenced items.

[0089] The terms “a,” “an,” “the,” “at least one,” and “one or more” are used interchangeably to indicate the presence of at least one of the items. Multiple such items may be present unless the context explicitly indicates otherwise. Unless otherwise explicitly or clearly indicated by the context, all numerical values ​​of parameters (e.g., quantities or conditions) in this specification, including the appended claims, will be understood to be modified in all cases by the term “about,” regardless of whether “about” actually precedes the numerical value. “About” indicates that the stated numerical value allows for a certain degree of slight imprecision (a degree of approximation to the value; approximately or reasonably close to the value; almost). If the imprecision provided by “about” is not otherwise understood in the art in that ordinary sense, then “about” as used herein at least indicates a variation that can be produced by ordinary methods of measuring and using such a parameter. Furthermore, a disclosure of a range will be understood to specifically disclose all values ​​and ranges further subdivided within that range.

[0090] Roughly estimated terms (such as “about,” “almost,” “basically,” “generally,” “approximately,” etc.) may be used herein in the sense of “for,” “close to,” or “nearly for,” or “within 0-5% of,” or “within acceptable manufacturing tolerances,” or logical combinations thereof. Moreover, as used herein, components “constructed” to perform a specified function are capable of performing that specified function without alteration, and not merely have the potential to perform that specified function after further modification. In other words, when explicitly constructed to perform a specified function, the described hardware is specifically selected, created, implemented, utilized, programmed, and / or designed for the purpose of performing that specified function. For consistency and convenience, directional adjectives corresponding to the illustrated embodiments may be used throughout this detailed description. Those skilled in the art will recognize that terms such as “above,” “below,” “upward,” “downward,” “top,” “bottom,” etc., are used descriptively with respect to the drawings and do not imply limitation of the scope of this disclosure as defined by the appended claims. For ease of description, spatial relative terms such as “inner,” “outer,” “below,” “below,” “down,” “above,” “upper,” etc., may be used in this document to describe the relationship of one element or feature to another or more elements or features, as illustrated in the figures. In addition to the orientations depicted in the figures, spatial relative terms may also be intended to cover different orientations of the apparatus or system in use or operation.

[0091] While various embodiments have been described, the description is intended to be illustrative and not restrictive, and it will be apparent to those skilled in the art that many other embodiments and implementations are possible within the scope of these embodiments. Unless specifically limited, any feature of any embodiment may be used in combination with or in lieu of any other feature or element in any other embodiment. Therefore, these embodiments are not limited except as limited by the appended claims and their equivalents. Moreover, various modifications and variations are possible within the scope of the appended claims. Although several modes for implementing many aspects of this teaching have been described in detail, those skilled in the art to which this teaching relates will recognize various alternative aspects within the scope of the appended claims for practicing this teaching. It is intended that all matters contained in the above description or illustrated in the drawings be construed as illustrating and illustrating the full range of alternative embodiments that will be recognized by those skilled in the art (such as those implied by the included content, structurally and / or functionally equivalent to the included content, or otherwise apparent based on the included content), and not limited to the embodiments explicitly depicted and / or described.

Claims

1. A control system for an electric vehicle, the system comprising: A motor controller configured to control the vehicle's motor according to one or more of a plurality of torque commands; as well as A motor spike controller is configured to generate a motor spike torque command as one of the plurality of torque commands, the motor spike torque command being configured to mitigate transmission torque spikes in the drivetrain, the drivetrain being configured to connect the motor to the wheels of the vehicle. The motor spike controller is configured to generate the motor spike torque command based on the torque spike equation, which is expressed as: Among them, T m It is the peak torque command of the motor, J m It is the motor inertia of the motor. Ratio is the wheel acceleration of the wheel, and Ratio is a constant representing the speed ratio between the motor and the wheel.

2. The system according to claim 1, wherein, The motor spike controller is configured to generate a motor spike torque command in response to an ice impact event caused by the vehicle crossing from a first surface to a second surface, the first surface having a first frictional force and the second surface having a second frictional force, the second frictional force differing from the first frictional force by a predetermined amount.

3. The system according to claim 1, wherein, The motor spike controller is configured to generate the motor spike torque command in response to a panic braking event that occurs due to the brakes on the vehicle causing the wheel speed to decelerate faster than a predetermined rate.

4. The system according to claim 1, wherein, The motor spike controller is configured to generate the motor spike torque command as a feedforward control.

5. A control method for mitigating torque spikes in the transmission system of an electric vehicle, the method comprising: A motor peak torque command is generated in response to a wheel acceleration exceeding a peak threshold of the vehicle's wheels. This motor peak torque command is configured to control the vehicle's electric motor to mitigate the transmission torque peak in the drivetrain, which is configured to connect the motor to the wheels. The motor peak torque command is generated based on the torque peak equation, which is expressed as follows: Among them, T m It is the peak torque command of the motor, J m It is the motor inertia of the motor. Ratio is the wheel acceleration of the wheel, and Ratio is a constant representing the speed ratio between the motor and the wheel.

6. The method of claim 5, further comprising: A wheel slip torque command is generated based on the wheel speed measured at the wheel, and the wheel slip torque command is configured to control the motor to alleviate wheel slip.

7. The method of claim 6, further comprising: The wheel flare torque command is generated based on the output speed of the transmission, which is included as part of the drivetrain, and the wheel flare torque command is configured to control the motor to mitigate wheel flare.

8. The method of claim 7, further comprising: The motor controller is configured to arbitrate between commanding the motor according to one of the motor peak torque command, the wheel slip torque command, and the wheel spread torque.

9. The method of claim 8, further comprising: The wheel slip controller is configured to generate a wheel slip torque command, the wheel spread controller is configured to generate a wheel spread torque command, and the motor spike controller is configured to generate the motor spike torque command.

10. The method of claim 9, further comprising: The motor spike controller generates the motor spike torque command in response to the wheel speed being greater than a wheel speed threshold or the output of the transmission being greater than a predetermined output acceleration threshold.

11. The method of claim 10, further comprising: Generate the motor peak torque command as feedforward control.

12. The method of claim 11, further comprising: Generate each of the wheel slip torque command and the wheel spread torque command as feedback control.

13. The method of claim 5, further comprising: Generate the motor peak torque command so that the motor inertia matches the wheel inertia in speed.

14. The method of claim 5, further comprising: Generate the motor peak torque command to control the motor speed to be close to the wheel speed.

15. A control system for an electric vehicle, the system comprising: A wheel slip controller is configured to control wheel slip based on the wheel speed measured at the wheels of the vehicle. A wheel flare controller is configured to control wheel flare based on the output speed of a transmission, the transmission being included as part of the vehicle's drivetrain. as well as A motor spike controller is configured to control transmission torque spikes based on the wheel acceleration of the wheel and the motor inertia of the motor connected to the wheel via the transmission system. The motor spike controller is configured to generate a motor spike torque command to control the motor and mitigate torque spikes in the transmission system. The motor spike controller is configured to generate the motor spike torque command based on a torque spike equation, which is expressed as: Among them, T m It is the peak torque command of the motor, J m It is the motor inertia of the motor. It is the wheel acceleration, and Ratio is a constant representing the speed ratio between the motor and the wheel.

16. The system of claim 15, further comprising a motor controller configured to arbitrate among the motors using the wheel slip controller, the wheel spread controller, and the motor spike controller.

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