System and method for freewheeling traction

Abstract

This disclosure relates to systems and methods for freewheel traction. Various disclosed embodiments include illustrative drive unit controllers, drive units, and vehicles. In an illustrative embodiment, the drive unit controller includes a processor having a computer-readable medium configured to store computer-executable instructions configured to cause the processor to receive freewheel traction mode activation information, activate a holding mode based on the received freewheel traction mode activation information, generate a zero-speed command in response to the activation of the holding mode, and send the generated zero-speed command to the stability system of the associated vehicle.

Description

Background Technology

[0001] This disclosure relates to electric vehicle traction. The statements in this section are provided only as background information in connection with this disclosure and may not constitute prior art.

[0002] like Figure 1 As shown, when an electric vehicle is to be towed by another vehicle (e.g., a motorhome (RV)), the towed electric vehicle is placed in neutral. After the vehicle is placed in neutral, wedges are used to secure the vehicle to ensure that it does not roll when the user attaches to the towing vehicle. Summary of the Invention

[0003] Various disclosed embodiments include illustrative drive unit controllers, drive units, and vehicles.

[0004] In an illustrative embodiment, the drive unit controller includes a processor having a computer-readable medium configured to store computer-executable instructions configured to cause the processor to receive freewheel traction mode activation information, activate a hold mode based on the received freewheel traction mode activation information, generate a zero-speed command in response to the activation of the hold mode, and send the generated zero-speed command to the stability system of the associated vehicle.

[0005] In another illustrative embodiment, the drive unit includes an electric motor, an encoder configured to generate motor speed information of the electric motor, an inverter configured to control the operation of the electric motor, and a drive unit controller. The drive unit controller includes a processor having a computer-readable medium configured to store computer-executable instructions configured to cause the processor to receive freewheel traction mode activation information, activate a hold mode based on the received freewheel traction mode activation information, generate a zero-speed command in response to the activation of the hold mode, and send the generated zero-speed command to the stability system of the associated vehicle.

[0006] In another illustrative embodiment, the vehicle includes a human-machine interface unit configured to generate a traction mode activation signal, a vehicle status unit configured to generate slope information, and a drive unit. The drive unit includes an electric motor, an encoder configured to generate motor speed information of the electric motor, an inverter configured to control the operation of the electric motor, and a drive unit controller. The drive unit controller includes a processor having a computer-readable medium configured to store computer-executable instructions configured to cause the processor to receive freewheel traction mode activation information, activate a hold mode based on the received freewheel traction mode activation information, generate a zero-speed command in response to the activation of the hold mode, and send the generated zero-speed command to the stability system of the associated vehicle.

[0007] The foregoing description of the invention is illustrative only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments, and features described above, other aspects, embodiments, and features will become apparent from the accompanying drawings and the following detailed description. Attached Figure Description

[0008] Illustrative embodiments are shown in the accompanying drawings. The embodiments and drawings disclosed herein are intended to be illustrative and not restrictive.

[0009] Figure 1 This is a diagram of a vehicle in traction operation.

[0010] Figure 2 This is a block diagram illustrating an electric vehicle.

[0011] Figure 3 It is by Figure 2 The flowchart illustrates the illustrative method performed by the ramp start assist system shown.

[0012] Similar reference numerals in the various figures typically indicate similar elements. Detailed Implementation

[0013] In the following detailed description, reference is made to the accompanying drawings, which form a part thereof. In the drawings, similar symbols generally identify similar parts unless the context otherwise indicates. The illustrative embodiments described in the detailed description, drawings, and claims are not intended to be limiting. Other embodiments and changes may be utilized without departing from the spirit or scope of the subject matter presented herein.

[0014] Various disclosed embodiments include illustrative drive unit controllers, drive units, and vehicles. In such embodiments, illustrative systems and methods can control vehicle traction operations on a slope.

[0015] Now for reference Figure 2 In various embodiments, the illustrative vehicle 20 includes components for using electric motor speed or torque control to provide assistance during vehicle traction situations. The illustrative vehicle 20 includes an electronic control unit (ECU) 30 that controls the operation of numerous components via a controller local area network (CAN) bus 28. Other point-to-point network buses, such as local area networks (LANs), wide area networks (WANs), or value-added networks (VANs), may also be used to enable communication between the ECU 30 and other components connected to the point-to-point network.

[0016] The ECU 30 communicates directly or via the CAN bus 28 with the accelerator 38, drive selector 42, braking system 56, and / or electronic power steering (EPS) 48. The ECU 30 also communicates via the CAN bus 28 with the human-machine interface (HMI) 40, a number of sensors 50, environmental control unit (EnvCU) 60, battery management unit (BMU) 32, on-board charger 44, and multiple drive units 36.

[0017] The drive unit 36 ​​may include an inverter 82, an encoder (e.g., a resolver) 84, and a motor 86, such as, but not limited to, a brushless DC (BLDC) motor, an AC induction motor (ACIM), a permanent magnet synchronous motor (PMSM), an internal PM motor (IPMM), a PM switched reluctance motor (PMSRM), or a similar battery-powered motor.

[0018] ECU 30 may include a data processor having a computer-readable medium configured to store computer-executable instructions configured to cause the data processor to perform certain functions. The computer-executable instructions are configured to cause the data processor to generate vehicle status information via a wireless communication device from data received from sensors 50, HMI 40, braking system 56, drive selector 42, accelerator 38, drive unit 36, EnvCU 60, BMU 32, on-board charger 44, or external devices. In response to generating the vehicle status information, the computer-executable instructions are configured to cause the data processor of ECU 30 to generate control signals for various other vehicle components, such as BMU 32, on-board charger 44, drive unit 36, EPS 48, EnvCU 60, HMI 40, sensors 50, suspension control unit (not shown), and / or other devices (e.g., window motors, rearview mirror motors, door motors, door lock motors, or airbag systems). The functions for controlling drive unit 36 ​​can be performed by a controller having a processor directly connected to inverter 82 and encoder 84. The processor has a computer-readable medium configured to store computer-executable instructions configured to cause the processor to perform some or all of the functions described herein. The drive unit controller can communicate with ECU 30 and other components via CAN bus 28.

[0019] In various embodiments, and given by way of example only and not limitation, various sensors 50 may include wheel speed sensors, gyroscopes, accelerometers, global positioning systems (GPS), light detection and ranging devices (LIDAR), cameras, or similar devices.

[0020] In various embodiments, and given by way of example only and not limitation, the HMI 40 may include mechanical buttons or switches, or may include optional graphical user interface features presented on a vehicle display device.

[0021] In various embodiments, and given by way of example only and not limitation, braking system 56 may include a foot pedal, brake solenoid or pressure sensor, handbrake, steering wheel-mounted brake plate, or similar braking component. In various embodiments, accelerator 38 may include a foot pedal, accelerator solenoid or pressure sensor, steering wheel-mounted accelerator plate, or similar accelerator component. In various embodiments, drive selector 42 may include a lever, switch, button, or similar device for selecting vehicle motion states (e.g., forward, reverse, tank drive, low gear, neutral). In various embodiments, EPS 48 may include a steering angle sensor, torque sensor, electric motor, and a pinion coupler connecting the motor and rack to the wheels.

[0022] In various embodiments, and given by way of example only and not limitation, the BMU 32 communicates with the battery pack 34 to generate battery status information, which is transmitted to the ECU 30 and EnvCU 60 via the CAN bus 28. The BMU 32 receives battery information from the battery pack 34 and / or from sensors associated with or included in the battery pack. Battery information may include state of charge (SOC), temperature, cell voltage, input / output current, coolant flow, or other values ​​important for battery operation. The BMU 32 uses the battery information to control battery charging and battery thermal management, and communicates with other vehicle components or external components such as fast-charging units, other vehicles, diagnostic computers, or other similar devices via the CAN bus 28.

[0023] In various embodiments, and given by way of example only and not limitation, vehicle 20 includes a standard AC charging connector 46 and / or a DC fast charging connector 54. The standard AC charging connector 46 supplies power to an on-board charger 44 according to instructions from an ECU 30. This on-board charger generates charging DC power, which is delivered to the battery pack 34 via a DC / DC converter 52. In response to communication with the BMU 32 and / or the ECU 30, the DC fast charging connector 54 can directly apply DC power from an external DC fast charging unit to the battery pack 34. The on-board charger 44 and / or the DC / DC converter 52 also generate DC voltage for other vehicle equipment, such as a 12V battery and other 12V compatible devices.

[0024] In various embodiments, and given by way of example only and not limitation, the EnvCU 60, powered by the battery pack 34 or by power generated by the DC / DC converter 52, maintains the environmental conditions of the vehicle 20's cabin, drive unit 36, and / or battery pack 34 in response to commands from the ECU 30, BMU 32, and / or HMI 40.

[0025] Inverter 82 provides motor drive signals to AC motor 86. Encoder 84 is attached to AC motor 86. Encoder 84 generates motor speed value signals for the corresponding AC motor 86 and provides these motor speed value signals to ECU 30. Inverter 82 generates motor drive signals in response to commands from ECU 30.

[0026] In various embodiments, the additional drive unit 36 ​​is used in multi-wheel drive vehicles. The following operational description applies to vehicles that include one or more drive units 36.

[0027] HMI 40 allows the vehicle operator to select from a variety of pre-programmed vehicle operating modes. One of the pre-programmed vehicle operating modes includes a free-wheel traction mode. In various embodiments, after vehicle 20 is placed in free-wheel traction mode, one of the drive units 36 is disconnected from the associated axle / wheel. Vehicle 20 includes a disconnect module that physically disconnects the rear wheels from the gearbox attached to the associated motor. However, the other drive unit 36 ​​remains connected to the associated axle / wheel and is instructed by ECU 30 to perform a hold (speed / torque control) function. The hold function causes ECU 30 to control motor 86 to prevent vehicle movement. The hold function is disabled when the traction exceeds a predefined threshold amount.

[0028] In various embodiments, ECU 30 may generate an initial motor control signal based on slope information received from sensor 50. If the slope information is zero or insufficient to cause vehicle 20 to roll, ECU 30 does not generate a motor control signal. If the slope information is greater than a predefined threshold amount, ECU 30 generates an initial motor speed signal or an initial motor torque signal. The generated initial motor speed signal or motor torque signal instructs inverter 82 / motor 86 to counteract any gravity related to the slope. After ECU 30 generates the initial motor control signal, ECU 30 receives motor speed information from encoder 84 and generates subsequent motor speed signals or motor torque signals in response to the received motor speed information. The newly generated motor speed signal or motor torque signal is compared with a predefined threshold. The predefined threshold instructs the motor control signal to increase in response to external forces (e.g., traction) on vehicle 20. Once the motor speed signal or motor control signal meets or exceeds the predefined threshold, ECU 30 stops generating motor speed signals or motor control signals. Vehicle 20 is now in an actively traction state.

[0029] For further reference Figure 3 In various embodiments, the vehicle 20 performs an illustrative process 50 for traction mode operation. At decision block 52, process 50 determines whether the user has activated freewheel traction mode via HMI 40. Once freewheel traction mode is activated, at block 54, the vehicle status system 34 or ECU 30 receives gradient information. The gradient information may be generated by one or more gyroscopes located at various locations on the vehicle 20, or it may be determined via GPS data. At block 56, ECU 30 applies a zero-speed command and calculates an initial torque (speed control or braking) value in response to the received gradient and vehicle weight information. The initial torque value is designed to prevent the vehicle 20 from rolling (at zero speed) if the gradient information indicates that the vehicle 20 may roll. At block 58, ECU 30 receives motor position information from encoder 84. At block 60, the controller adjusts the torque value in response to the received motor position information. At decision block 62, ECU 30 determines whether the adjusted torque value is greater than a predefined threshold amount. Inverter 82 converts the torque value into a voltage value, which is sent to motor 86. A predefined threshold amount indicates that the traction vehicle is attached to vehicle 20 and is applying traction to it. A higher torque value indicates that ECU 30 is attempting to counteract the motion detected by encoder 84, thus indicating that an external force is being applied to vehicle 20. If the torque value is greater than the predefined threshold amount, at box 64, the zero-speed command is disabled, and vehicle 20 continues to operate in freewheel traction mode until the user deselects it. In other words, the torque command is no longer adjusted to keep the vehicle speed at zero.

[0030] It should be understood that the above process 50 can also be applied to braking systems. The braking value can replace the torque value.

[0031] Those skilled in the art will recognize that at least a portion of the ECU 30, BMU 36, on-board charger 44, HMI 40, controller, components, devices, and / or processes described herein can be integrated into a data processing system. Those skilled in the art will recognize that a data processing system typically includes one or more of the following: a system unit housing, a video display device, memory such as volatile or non-volatile memory, a processor such as a microprocessor or digital signal processor, computing entities such as an operating system, drivers, graphical user interfaces, and applications, one or more interactive devices (e.g., touchpad, touchscreen, antenna, etc.), and / or a control system, including feedback loops and control motors (e.g., feedback for sensing position and / or speed; control motors for moving and / or adjusting components and / or quantities). The data processing system can be implemented using suitable commercially available components, such as those commonly found in data computing / communication and / or network computing / communication systems.

[0032] As used in the foregoing / subsequent disclosures, the term "unit / module / controller" can refer to a collection of one or more components arranged in a particular manner, or a collection of one or more general-purpose components that can be configured to operate in a particular manner at one or more specific points in time and / or also configured to operate in one or more other manners at one or more additional times. For example, the same hardware or the same portion of hardware can be configured / reconfigured in consecutive / parallel time as a first type of component (e.g., at a first time), a second type of component (e.g., at a second time, in some cases, the second time may coincide with, overlap with, or succeed the first time), and / or a third type of component (e.g., at a third time, in some cases, the third time may coincide with, overlap with, or succeed the first and / or second times). Reconfigurable and / or controllable components (e.g., general-purpose processors, digital signal processors, field-programmable gate arrays, etc.) can be configured as a first module with a first purpose, then as a second module with a second purpose, then as a third module with a third purpose, and so on. Transformation of reconfigurable and / or controllable components can occur in as little as a few nanoseconds, or over time periods of minutes, hours, or days.

[0033] In some such examples, when a component is configured to perform a secondary purpose, it may no longer be able to perform that primary purpose until it is reconfigured. A component can switch between configurations as different components in as few nanoseconds. A component can be reconfigured in operation; for example, reconfiguring a component from a first component to a second component can occur precisely when the second component is needed. A component can be reconfigured in stages; for example, a portion of the first component that is no longer needed can be reconfigured to the second component even before the first component has completed its operation. Such reconfiguration can occur automatically or be prompted by an external source, whether that source is another component, instruction, signal, condition, external stimulus, or the like.

[0034] For example, the central processing unit of a personal computer can be configured according to its instructions to use its logic gates at different times as a component for displaying graphics on a screen, a component for writing data to a storage medium, a component for receiving user input, and a component for multiplying two large prime numbers. Such reconfiguration may be invisible to the naked eye, and in some embodiments, may include the activation, deactivation, and / or rerouting of portions of the components (e.g., switches, logic gates, inputs, and / or outputs). Therefore, in the examples seen in the foregoing / subsequent disclosures, if the example includes or enumerates multiple components, the example includes the possibility that the same hardware may be implemented with more than one of the enumerated components simultaneously or at discrete times or junctures. The implementation of multiple components, whether using more components, fewer components, or the same number of components as the number of components, is merely an implementation choice and generally does not affect the operation of the components themselves. Therefore, it should be understood that any description of multiple discrete components in this disclosure includes implementing these components as any number of underlying components, including but not limited to a single component that reconfigures itself over time to perform the functions of multiple components, and / or multiple components that are similarly reconfigured, and / or dedicated reconfigurable components.

[0035] In some cases, one or more components may be referred to herein as “configured to,” “configured by,” “configurable to,” “operable / operable to,” “suitable / adaptable to,” “capable of,” “compliant / compliant,” etc. Those skilled in the art will recognize that, unless the context otherwise requires, such terms (e.g., “configured to”) generally cover active state components and / or inactive state components and / or standby state components.

[0036] While specific aspects of the subject matter of the invention described herein have been shown and described, it will be apparent to those skilled in the art that changes and modifications can be made based on the teachings herein without departing from the subject matter and its broader aspects. Therefore, the appended claims are intended to cover within their scope all such changes and modifications that fall within the true spirit and scope of the subject matter described herein. Those skilled in the art will understand that, generally, the terms used herein, particularly in the appended claims (e.g., the body of the appended claims), are generally intended to be “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “at least having,” the term “includes” should be interpreted as “including but not limited to,” etc.). Those skilled in the art will further understand that if the intention is to include a specific number of introductory claim enumerations, such an intention will be explicitly stated in the claims; if such a statement is not present, such an intention is not present. For example, as an aid to understanding, the appended claims may contain the use of the introductory phrases “at least one” and “one or more” to introduce claim enumerations. However, the use of such phrases should not be construed as implying that the introduction of a claim enumeration by the indefinite article “a” (“a” or “an”) limits any particular claim containing such an introductory claim enumeration to a claim containing only one such enumeration, even when the same claim includes the introductory phrase “one or more” or “at least one” and an indefinite article such as “a” (e.g., “a” should generally be interpreted as meaning “at least one” or “one or more”); the same applies to the use of definite articles used to introduce claim enumerations. Furthermore, even when a specific number of introductory claim enumerations is explicitly stated, those skilled in the art will recognize that such a statement should generally be interpreted as indicating at least the number stated (e.g., in the absence of other modifiers, the bare statement “two enumerations” generally means at least two enumerations, or two or more enumerations). Furthermore, in cases where conventional usages such as "at least one of A, B, and C" are applied, this construction is generally intended for use by those skilled in the art to understand the meaning of the conventional usage (e.g., "a system having at least one of A, B, and C" will include, but is not limited to, systems having only A, only B, only C, A and B, A and C, B and C, and / or A, B, and C, etc.). Those skilled in the art will further understand that, unless the context otherwise indicates, alternative terms and / or phrases that typically give two or more alternative terms, whether in the specification, claims, or drawings, should be understood to cover the possibility of including one, any one, or both of the terms. For example, the phrase "A or B" should generally be understood to include the possibility of "A" or "B" or "A and B".

[0037] The foregoing detailed embodiments have illustrated various embodiments of the apparatus and / or processes using block diagrams, flowcharts, and / or examples. Those skilled in the art will understand that, with regard to the inclusion of one or more functions and / or operations in these block diagrams, flowcharts, and / or examples, each function and / or operation can be implemented individually and / or collectively by a wide range of hardware, software (e.g., high-level computer programs acting as hardware specifications), firmware, or virtually any combination thereof, but limited to the patentable subject matter under 35U.SC101. In embodiments, certain portions of the subject matter described herein can be implemented via application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), digital signal processors (DSPs), or other integration formats. However, those skilled in the art will recognize that some aspects of the embodiments disclosed herein can be equivalently implemented in an integrated circuit, as one or more computer programs running on one or more computers (e.g., one or more programs running on one or more computer systems), as one or more programs running on one or more processors (e.g., one or more programs running on one or more microprocessors), as firmware, or virtually any combination thereof, but limited to the patentable subject matter under 35U.SC101, and will recognize that, in consideration of this disclosure, designing circuits and / or writing software code (e.g., high-level computer programs that act as hardware specifications) and / or firmware will be entirely within the skill of those skilled in the art. Furthermore, those skilled in the art will understand that the mechanisms of the subject matter described herein can be distributed as program products in various forms, and exemplary embodiments of the subject matter described herein apply regardless of the specific type of signal-bearing medium used for the actual execution of the distribution. Examples of signal-bearing media include, but are not limited to: recordable media such as floppy disks, hard disks, compact discs (CDs), digital video discs (DVDs), digital magnetic tapes, computer memory, etc.; and transmission media such as digital and / or analog communication media (e.g., optical fiber, waveguides, wired communication links, wireless communication links (e.g., transmitters, receivers, transmission logic, receiving logic, etc.) etc.).

[0038] Regarding the appended claims, those skilled in the art will understand that the operations described herein can generally be performed in any order. Furthermore, although various flows of operations are presented in one or more sequences, it should be understood that the various operations can be performed in orders other than those illustrated, or can be performed simultaneously. Examples of such alternative orders may include overlapping, interleaving, interrupted, reordered, ascending, preparatory, supplementary, simultaneous, reverse, or other variant orders, unless the context otherwise requires. Moreover, unless the context otherwise requires, terms such as “in response to,” “related to,” or other past tense adjectives are generally not intended to exclude such variants.

[0039] Although the disclosed subject matter has been described with reference to exemplary embodiments, those skilled in the art will understand that various modifications may be made thereto without departing from the scope of the claimed subject matter set forth in the claims.

Claims

1. A controller, comprising: A processor having a computer-readable medium configured to store computer-executable instructions configured to cause the processor to: Receive freewheel traction mode activation information from the associated vehicle; Receive slope information; The hold mode is activated based on the received freewheel traction mode activation information and slope information; A zero-speed command is generated in response to the activation of the holding mode. The zero-speed command calculates an initial torque value in response to received slope information and vehicle weight information. The initial torque value is designed to prevent the associated vehicle from rolling if the slope information indicates that the associated vehicle may roll. Send the generated zero-speed command to the stability system of the associated vehicle; The generated zero-speed command is compared with a threshold indicating that the tractor vehicle has been attached to the associated vehicle and is applying traction to the associated vehicle; as well as In response to the generated zero-speed command being greater than the threshold, the hold mode is deactivated, causing the processor to stop generating the zero-speed command, and the associated vehicle continues to operate in freewheel traction mode until the freewheel traction mode is deselected by the user.

2. The controller of claim 1, wherein the computer-executable instructions are further configured to cause the processor to adjust the zero-speed command in response to motor position information.

3. The controller of claim 2, wherein the stabilization system includes an inverter and a motor of a drive unit, the inverter being configured to receive the zero-speed command and to direct the motor operation in response to the zero-speed command.

4. The controller of claim 1, wherein the stabilization system includes an inverter and a motor of a drive unit, the inverter being configured to receive the zero-speed command and, in response to the zero-speed command, to direct the operation of the motor.

5. The controller of claim 1, wherein the zero speed command includes a braking command.

6. The controller of claim 5, wherein the stabilization system includes a braking system configured to receive the braking command and apply an associated braking action in response to the braking command.

7. A driving unit, comprising: Electric motor; An encoder configured to generate motor speed information of the electric motor; An inverter configured to control the operation of the motor; as well as Controller, the controller includes: A processor having a computer-readable medium configured to store computer-executable instructions configured to cause the processor to: Receive freewheel traction mode activation information from the associated vehicle; Receive slope information; The hold mode is activated based on the received freewheel traction mode activation information and slope information; A zero-speed command is generated in response to the activation of the holding mode. The zero-speed command calculates an initial torque value in response to received slope information and vehicle weight information. The initial torque value is designed to prevent the associated vehicle from rolling if the slope information indicates that the associated vehicle may roll. Send the generated zero-speed command to the inverter; The generated zero-speed command is compared with a threshold indicating that the tractor vehicle is attached to the associated vehicle and is applying traction to the associated vehicle; and In response to the generated zero-speed command being greater than the threshold, the hold mode is deactivated, causing the processor to stop generating the zero-speed command, and the associated vehicle continues to operate in freewheel traction mode until the freewheel traction mode is deselected by the user.

8. The drive unit of claim 7, wherein the computer-executable instructions are further configured to cause the processor to generate the zero-speed command in response to the motor speed information.

9. A vehicle comprising: A human-machine interface unit, configured to generate a freewheel traction mode activation signal; A vehicle status unit, configured to generate slope information; as well as The drive unit includes: Electric motor; An encoder, configured to generate motor speed information for the electric motor; and An inverter configured to control the operation of the motor; and The controller includes a processor having a computer-readable medium configured to store computer-executable instructions, the computer-executable instructions being configured to cause the processor to: Receive the generated freewheel traction mode activation signal from the human-machine interface unit; Receive the generated slope information from the vehicle status unit; The hold mode is activated in response to the received freewheel traction mode activation signal and slope information; A zero-speed command is generated in response to the activation of the holding mode. The zero-speed command calculates an initial torque value in response to received slope information and vehicle weight information. The initial torque value is designed to prevent the vehicle from rolling if the slope information indicates that the vehicle may roll. Send the generated zero-speed command to the inverter; The generated zero-speed command is compared with a threshold indicating that the traction vehicle is attached to the vehicle and is applying traction to the vehicle; and In response to the generated zero-speed command being greater than the threshold, the hold mode is deactivated, causing the processor to stop generating the zero-speed command, and the vehicle continues to operate in freewheel traction mode until the freewheel traction mode is deselected by the user.

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