Drive torque demand for achieving coordination between vehicle torque sources

Abstract

A control system for a vehicle having a vehicle drive system and a plurality of torque sources connected to the vehicle drive system, the control system instructing a first torque source of the plurality of torque sources to provide an instantaneous torque to the vehicle drive system. The data processing hardware also receives a torque output requested by a driver of the vehicle and obtains a first available torque source output of the first torque source. The data processing hardware calculates a first torque error based on the requested torque output and a first available torque source output of the first torque source. The data processing hardware determines whether the first torque error exceeds a torque error threshold and activates a first supplemental torque source of the plurality of torque sources to provide a first supplemental torque output to the vehicle drive system when the first torque error exceeds the torque error threshold.

Description

Technical Field

[0001] The present invention generally relates to systems and methods for sensing torque to achieve coordination between vehicle torque sources. Background Art

[0002] The information provided in this section is for the purpose of generally presenting the background of the present disclosure. To the extent described in this section, the work of the presently named inventors, as well as aspects of the description that may not qualify as prior art at the time of filing, are neither explicitly nor implicitly admitted to be prior art with respect to the present disclosure.

[0003] Passenger comfort and fuel efficiency place increasing demands on motor vehicle design. A primary goal of most vehicle designs is to provide a more efficient vehicle without sacrificing vehicle performance. Furthermore, with the implementation of alternative vehicle propulsion systems, vehicle performance and fuel efficiency are sometimes in opposition to each other.

[0004] A hybrid vehicle is a vehicle that has two sources of propulsion. A hybrid electric vehicle (HEV) is a vehicle where one of the propulsion sources is electric and the other propulsion source can come from a fuel cell or an internal combustion engine (ICE) burning diesel, gasoline or any other fuel source. Typically, a hybrid vehicle utilizes one or two drive trains, where the internal combustion engine (ICE) provides torque to one of the drive trains and the electric drive force is applied to either of the two drive trains.

[0005] In order to operate the internal combustion engine (ICE) of a hybrid vehicle, a fuel source must be consumed. This causes the engine to produce emissions, and reducing such emissions is a primary goal of any hybrid vehicle design. Electric drive systems, on the other hand, produce little or no emissions. However, the operation of such systems draws energy from one or more batteries, which must eventually be recharged.

[0006] Therefore, in order to operate in the most efficient manner, one or both energy sources of a hybrid vehicle should be operated according to the most efficient use of energy. Summary of the invention

[0007] In one configuration, a computer-implemented method that, when executed by data processing hardware of a vehicle having a vehicle drive system and a plurality of torque sources connected to the vehicle drive system, causes data processing hardware to perform operations. One operation includes instructing a first torque source among the plurality of torque sources to provide instantaneous torque to the vehicle drive system. Another operation of the method includes receiving a requested torque output of the vehicle drive system. Another operation of the method includes obtaining a first available torque source output of the first torque source. Yet another operation includes calculating a first torque error based on the requested torque output and the first available torque source output of the first torque source. Another operation includes determining whether the first torque error exceeds a torque error threshold. When the first torque error exceeds the torque error threshold, the method includes starting a first supplemental torque source among the plurality of torque sources to provide a first supplemental torque output to the vehicle drive system.

[0008] The method may include one or more of the following optional features. In some examples, the operations further include obtaining a supplemental available torque source output of a first supplemental torque source, calculating a total torque error based on the requested torque output and the supplemental available torque source output, determining whether the total torque error exceeds a torque error threshold, and when the total torque error exceeds the torque error threshold, instructing a second supplemental torque source of the plurality of torque sources to provide a second supplemental additional torque output to the vehicle drive system.

[0009] In some examples, the operation further includes determining a requested torque output based on the measured vehicle speed and the requested vehicle speed. In some configurations, the first available torque source output includes at least one of an instantaneous current torque source output component and a maximum current torque source output component. In some embodiments, starting a first supplemental torque source among the plurality of torque sources includes starting an available torque source with a highest efficiency score. In some examples, the plurality of torque sources include one or more electric motors. In these examples, the plurality of torque sources may include an internal combustion engine.

[0010] In some configurations, the operations further include instructing the first supplemental torque source to perform a ramp-up period prior to providing the first supplemental torque output. In these configurations, the ramp-up period may include operating the first supplemental torque source in a no-load state prior to providing the first supplemental torque output.

[0011] In another aspect of the present disclosure, a control system for a vehicle is provided, the vehicle having a vehicle drive system and a plurality of torque sources connected to the vehicle drive system. The control system includes data processing hardware and memory hardware in communication with the data processing hardware, the memory hardware storing instructions that, when executed on the data processing hardware, cause the data processing hardware to perform operations. One operation includes instructing a first torque source among a plurality of torque sources to provide instantaneous torque to the vehicle drive system. Another operation includes receiving a requested torque output of the vehicle drive system. Yet another operation includes obtaining a first available torque source output of the first torque source. Yet another operation includes calculating a first torque error based on the requested torque output and the first available torque source output of the first torque source. Another operation includes determining whether the first torque error exceeds a torque error threshold. When the first torque error exceeds the torque error threshold, the operation includes starting a first supplemental torque source among a plurality of torque sources to provide a first supplemental torque output to the vehicle drive system.

[0012] This aspect of the disclosure may include one or more of the following optional features. In some examples, the operations further include obtaining a supplemental available torque source output of a first supplemental torque source, calculating a total torque error based on the requested torque output and the supplemental available torque source output, determining whether the total torque error exceeds a torque error threshold, and when the total torque error exceeds the torque error threshold, instructing a second supplemental torque source among the plurality of torque sources to provide a second supplemental additional torque output to the vehicle drive system.

[0013] In some examples, the operation further comprises determining a requested torque output based on a measured vehicle speed and a requested vehicle speed. In some configurations, the first available torque source output comprises at least one of an instantaneous current torque source output component and a maximum current torque source output component. In some embodiments, starting a first supplemental torque source among the plurality of torque sources comprises starting an available torque source having a highest efficiency score. In some examples, the plurality of torque sources comprises one or more electric motors. In some embodiments, the plurality of torque sources comprises an internal combustion engine.

[0014] In some examples, the operations further include instructing the first supplemental torque source to perform a ramp-up period prior to providing the first supplemental torque output. In these examples, the ramp-up period includes operating the first supplemental torque source at a no-load condition prior to providing the first supplemental torque output.

[0015] Another aspect of the present disclosure provides a computer-implemented method that, when executed by data processing hardware of a vehicle having a vehicle drive system and a plurality of torque sources connected to the vehicle drive system, causes data processing hardware to perform operations. The operations include: instructing a first torque source among the plurality of torque sources to provide instantaneous torque to the vehicle drive system; receiving a requested torque output of the vehicle drive system; obtaining a first available torque source output of the first torque source; calculating a first torque error based on the requested torque output and the first available torque source output of the first torque source; and determining whether the first torque error exceeds a torque error threshold. When the first torque error exceeds the torque error threshold, the operations include obtaining efficiency scores of one or more supplemental torque sources; and selecting a first supplemental torque source having a highest efficiency score from the plurality of supplemental torque sources to provide a first supplemental torque output to the vehicle drive system.

[0016] In some examples, the operations further include selecting an internal combustion engine as a first supplemental torque source and instructing the internal combustion engine to perform a ramp-up routine to warm up the internal combustion engine in an unloaded state before providing the first supplemental torque output to the vehicle drive system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings described herein are for illustrative purposes only of selected configurations and are not intended to limit the scope of the present disclosure.

[0018] Figure 1 is a schematic diagram of an example arrangement of a vehicle control system according to the principles of the present disclosure; and

[0019] Figure 2 is used Figure 1 An example arrangement of vehicle operations implemented by a control system.

[0020] Corresponding reference characters indicate corresponding parts throughout the several views. DETAILED DESCRIPTION

[0021] Example configurations will now be described more fully with reference to the accompanying drawings. Example configurations are provided so that the present disclosure will be thorough and will fully convey the scope of the present disclosure to those of ordinary skill in the art. Specific details, such as examples of specific components, devices, and methods, are set forth to provide a thorough understanding of the configurations of the present disclosure. It will be apparent to those of ordinary skill in the art that specific details need not be employed, that example configurations may be implemented in many different forms, and that the specific details and exemplary configurations should not be construed as limiting the scope of the present disclosure.

[0022] The terms used herein are only for describing specific exemplary configurations, not for limiting. As used herein, the singular articles "a", "an" and "the" may also be intended to include plural forms, unless the context clearly indicates otherwise. The terms "comprise", "include", "contain" and "have" are inclusive, thus specifying the presence of features, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, steps, operations, elements, parts and / or groups thereof. The method steps, processes and operations described herein should not be interpreted as necessarily requiring them to be performed in the specific order discussed or shown, unless specifically identified as an execution order. Additional or alternative steps may be adopted.

[0023] When an element or layer is referred to as being "on another element or layer," "engaged to," "connected to," "attached to," or "coupled to" another element or layer, it may be directly on, engaged, connected, attached to, or coupled to another element or layer, or there may be intermediate elements or layers. Conversely, when an element is referred to as being "directly on another element or layer," "directly engaged to," "directly connected to," "directly attached to," or "directly coupled to" another element or layer, there may be no intermediate elements or layers. Other words used to describe the relationship between elements should be interpreted in a similar manner (e.g., "between" versus "directly between," "adjacent" versus "directly adjacent," etc.). As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0024] The terms first, second, third, etc. can be used here to describe various elements, components, regions, layers and / or parts. These elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish each element, component, region, layer or part. Terms such as "first", "second" and other numerical terms do not imply order or sequence unless the context clearly indicates. Therefore, the first element, component, region, layer or part discussed below can be referred to as the second element, component, region, layer or part, without departing from the teaching of the example configuration.

[0025] In this application, including the definitions below, the term module may be replaced by the term circuit. The term "module" may refer to or be part of an application specific integrated circuit (ASIC), or include an application specific integrated circuit (ASIC); a digital, analog, or mixed analog / digital discrete circuit; a digital, analog, or mixed analog / digital integrated circuit; a combinational logic circuit; a field programmable gate array (FPGA); a processor (shared, dedicated, or group) that executes code; a memory (shared, dedicated, or group) that stores code executed by the processor; other suitable hardware components that provide the functionality; or a combination of some or all of the above, such as in a system on a chip.

[0026] The term code used above may include software, firmware and / or microcode, and may refer to a program, a routine, a function, a class and / or an object. The term shared processor includes a single processor that executes some or all of the code from multiple modules. The term group processor includes a processor that executes some or all of the code from one or more modules in combination with an additional processor. The term shared memory includes a single memory that stores some or all of the code from multiple modules. The term group memory includes a memory that stores some or all of the code from one or more modules in combination with an additional memory. The term memory may be a subset of the term computer-readable medium. The term computer-readable medium does not include transient electrical signals and electromagnetic signals propagated through the medium and can therefore be considered to be tangible non-transitory memory. Non-limiting examples of non-transitory memory include tangible computer-readable media, including non-volatile memory, magnetic memory, and optical memory.

[0027] The apparatus and methods described in this application may be implemented in part or in whole by one or more computer programs executed by one or more processors. The computer program includes processor executable instructions stored on at least one non-transitory tangible computer readable medium. The computer program may also include and / or rely on stored data.

[0028] Software applications (i.e., software resources) may refer to computer software that enables a computing device to perform tasks. In some examples, software applications may be referred to as "applications," "apps," or "programs." Example applications include, but are not limited to, system diagnostic applications, system management applications, system maintenance applications, word processing applications, spreadsheet applications, messaging applications, media streaming applications, social networking applications, and gaming applications.

[0029] Non-transitory memory can be a physical device used to temporarily or permanently store programs (e.g., instruction sequences) or data (e.g., program state information) for use by a computing device. Non-transitory memory can be volatile and / or non-volatile addressable semiconductor memory. Examples of non-volatile memory include, but are not limited to, flash memory and read-only memory (ROM) / programmable read-only memory (PROM) / erasable programmable read-only memory (EPROM) / electrically erasable programmable read-only memory (EEPROM) (e.g., commonly used for firmware, such as bootloaders). Examples of volatile memory include, but are not limited to, random access memory (RAM), dynamic random access memory (DRAM), static random access memory (SRAM), phase change memory (PCM), and disk or tape.

[0030] These computer programs (also referred to as programs, software, software applications, or code) include machine instructions for a programmable processor and may be implemented in high-level procedural and / or object-oriented programming languages ​​and / or assembly / machine languages. As used herein, the terms "machine-readable medium" and "computer-readable medium" refer to any computer program product, non-transitory computer-readable medium, apparatus, and / or device (e.g., disk, optical disk, memory, programmable logic device (PLD)) for providing machine instructions and / or data to a programmable processor, including a machine-readable medium that receives machine instructions as a machine-readable signal. The term "machine-readable signal" refers to any signal for providing machine instructions and / or data to a programmable processor.

[0031] Various implementations of the systems and techniques described herein can be realized in digital electronic and / or optical circuits, integrated circuits, specially designed ASICs (application specific integrated circuits), computer hardware, firmware, software, and / or combinations thereof. These various implementations may include implementations in one or more computer programs executable and / or interpretable on a programmable system comprising at least one programmable processor, which may be special purpose or general purpose, coupled to receive data and instructions from a storage system, and to send data and instructions to the storage system.

[0032] The processes and logic flows described in this specification can be performed by one or more programmable processors, also known as data processing hardware, executing one or more computer programs to perform functions by operating on input data and generating outputs. These processes and logic flows can also be performed by dedicated logic circuits, such as FPGAs (field programmable gate arrays) or ASICs (application-specific integrated circuits). For example, processors suitable for executing computer programs include general-purpose and special-purpose microprocessors, and any one or more processors of any kind of digital computer. Typically, the processor will receive instructions and data from a read-only memory or a random access memory or both. The basic elements of a computer are a processor for executing instructions and one or more storage devices for storing instructions and data. Typically, a computer will also include or be operably connected to one or more large-capacity storage devices for storing data, such as magnetic disks, magneto-optical disks, or optical disks, to receive data from the large-capacity storage device or to transmit data to it, or both. However, a computer does not need to have such a device. Computer-readable media suitable for storing computer program instructions and data include all forms of non-volatile memory, media and storage devices, including, for example, semiconductor memory devices, such as EPROM, EEPROM and flash memory devices; magnetic disks, such as internal hard disks or removable disks; magneto-optical disks; and CD ROM and DVD-ROM disks. The processor and memory may be supplemented by or incorporated in special purpose logic circuitry.

[0033] To provide interaction with a user, one or more aspects of the present disclosure may be implemented on a computer having a display device for displaying information to the user, such as a CRT (cathode ray tube), LCD (liquid crystal display) monitor, or touch screen, and an optional keyboard and pointing device, such as a mouse or trackball, through which the user can provide input to the computer. Other types of devices may also be used to provide interaction with the user; for example, the feedback provided to the user may be any form of sensory feedback, such as visual feedback, auditory feedback, or tactile feedback; and input from the user may be received in any form, including sound, voice, or tactile input. In addition, the computer may interact with the user by sending documents to and receiving documents from a device used by the user; for example, by sending a web page to a web browser on a user's client device in response to a request received from the web browser.

[0034] Referring now to the drawings, which are intended only to illustrate aspects of the present disclosure and not to limit the present disclosure, Figure 1A vehicle 10 is shown including a vehicle drive system 100 and a system controller 130 configured according to an example of the present disclosure. In the illustrated example, the vehicle drive system 100 includes a hybrid vehicle drive system 100 having a plurality of torque sources 102, 104 operable to provide drive torque to a transmission 106, which provides drive torque to a driveline 108. The torque sources may include an internal combustion engine 102 and one or more electric motors 104 operable to convert electrical energy supplied from an energy storage device 110 to produce drive torque.

[0035] In the illustrated example, the transmission 106 may include a two-mode, compound-split, electromechanical transmission 106 having fixed gear ratios and including a plurality of gears operable to transfer drive torque to a driveline 108 through a plurality of torque-transmitting devices contained therein. While the illustrated example shows the torque sources 102, 104 providing torque to a single transmission 106 (illustrated by a composite connecting line), it should be appreciated that the torque sources 102, 104 may provide torque to one or more independent transmissions 106 coupled to one or more drivelines 108. For example, the internal combustion engine 102 (where included) may be coupled to a first transmission 106, while the electric motor 104 may be coupled to a second transmission 106. Alternatively, the electric motor 104 may be coupled directly to an independent driveline at one or more wheels 12 of the vehicle 10.

[0036] The illustrated vehicle drive system 100 is configured according to one aspect of the present disclosure. The transmission 106 receives input torque from torque sources 102, 104, which include internal combustion engines 102 and electric motors 104, which are the result of energy conversion of fuel or electric potential stored in an electric energy storage device (ESD) 110. ESD110 generally includes one or more batteries. Without changing the concept of the present disclosure, other electric energy storage devices with the ability to store and distribute electricity can be used instead of batteries. The size of ESD110 is based on factors including regeneration requirements, application issues related to typical road slopes and temperatures, and propulsion requirements (such as emissions, power assist, and electric range). ESD110 is DC-coupled to a transmission power inverter module (TPIM) 112 by a DC line called an ESD transmission conductor 114 at a high voltage. TPIM112 transmits electrical energy to one or more electric motors 104 through an electric motor transmission conductor 116. Depending on whether ESD110 is charged or discharged, current can be transmitted between the electric motor 104 and ESD110. The TPIM 112 includes a power inverter and a corresponding motor control module configured to receive motor control commands and control inverter states accordingly to provide motor drive or regeneration functionality.

[0037] The electric motor 104 comprises a motor / generator device. In motor control, the corresponding inverter receives current from the ESD 110 and provides AC current to the corresponding motor 104 through the motor transfer conductor 116. In regenerative control, the corresponding inverter receives AC current from the electric motor 104 through the corresponding motor transfer conductor 116 and provides current to the ESD transfer conductor 114. The net DC current provided to or from the inverter determines the charging or discharging operating mode of the ESD 110.

[0038] Figure 1 The elements shown in and described below provide a subset of the overall vehicle control architecture and are operable to provide coordinated system control of the vehicle drive system 100 described herein. The system controller 130 is operable to collect and synthesize relevant information and inputs and execute algorithms to control various actuators to achieve control objectives. Control objectives include parameters such as fuel economy, emissions, performance, drivability, and hardware protection, including the battery of the ESD 110 and one or more electric motors 104. The distributed control module architecture of the system controller 130 includes an engine control module (ECM) 134, a transmission control module (TCM) 136, a battery pack control module ("BPCM") 138, and a transmission power inverter module (TPIM) 112. A hybrid control module (HCM) 132 provides overall control and coordination of the aforementioned control modules. The vehicle may include a user interface (UI) 140 operably connected to a plurality of devices, through which the vehicle operator typically controls or directs the operation of the powertrain including the transmission 106. Example vehicle operator inputs to the UI 140 include an accelerator pedal input 142, a brake pedal input 144, a transmission gear selector input 146, and a vehicle speed cruise control input 148. Within the system controller 130 and the vehicle 10, each of the aforementioned control modules 132, 134, 136, 138 communicates with other control modules, sensors, and actuators via a local area network (LAN) communication bus 150. The LAN communication bus 150 allows structured communication of control parameters and commands between the various control modules and components of the vehicle drive system 100. The specific communication protocol used is application specific. For example, one communication protocol is the Society of Automotive Engineers standard J1939. The LAN bus and appropriate protocols provide reliable messaging and multi-control module interfaces between the aforementioned control modules and other control modules that provide functions such as anti-lock braking, traction control, and vehicle stability.

[0039] The HCM 132 provides overall control of the hybrid vehicle drive system, coordinating the operation of the ECM 134, TCM 136, TPIM 112, and BPCM 138. Based on various input signals from the UI 140 and the vehicle drive system 100, the HCM 132 generates various requests or commands, including: internal combustion engine torque commands, clutch torque commands for various clutches of the hybrid transmission 106, and electric motor torque commands for the electric motor 104, respectively.

[0040] The ECM 134 is operably connected to the internal combustion engine 102 and is used to obtain data from various sensors and control various actuators of the internal combustion engine 102 through multiple discrete lines, which are collectively shown as a collection line 118. The ECM 134 receives an axle torque request 133 from the HCM 132 and generates an internal combustion engine torque command 135. For simplicity, the ECM 134 is generally shown as having a bidirectional interface with the engine 102 via the collection line 118. Various parameters sensed by the ECM 134 include engine coolant temperature, engine input speed of the transmission, manifold pressure, ambient air temperature, and ambient pressure. Various actuators that can be controlled by the ECM 134 include fuel injectors, ignition modules, and throttle control modules.

[0041] The TCM 136 is operably connected to the transmission 106 and is used to acquire data from various sensors and provide command control signals (i.e., clutch torque commands) to the clutches of the transmission 106. The BPCM 138 interacts with various sensors associated with the ESD 110 to provide information about the state of the ESD 110 to the HCM 132. Such sensors include voltage and current sensors, as well as environmental sensors operable to measure operating conditions of the ESD 110, including, for example, temperature and internal resistance of the ESD 110. The sensed parameters may include the ESD voltage V BAT 、ESD current I BAT and ESD temperature T BAT The derived parameters can include the ESD internal resistance R BAT , ESD charge state SOC and other states of ESD, including available power P BAT-MIN and P BAT-MAX .

[0042] The transmission power inverter module (TPIM) 112 includes the aforementioned power inverter and a motor control module, which is configured to receive motor control commands and thereby control the inverter state to provide motor drive or regeneration functions. The TPIM 112 is operable to generate an electric motor torque command 113 for the electric motor 104 based on the axle torque request 133 from the HCM 132, which is driven by operator input and system operating parameters through the UI 140. The motor torque is executed by the system controller 130 including the TPIM 112 to control the electric motor 104. The various motor speed signals are derived by the TPIM 112 from motor phase information or conventional rotation sensors. The TPIM 112 determines the motor speed and transmits it to the HCM 132.

[0043] Any of the aforementioned control modules 134, 136, 138, 132 of the system controller 130 and / or control system 130 may be incorporated as a general purpose digital computer, which typically includes a microprocessor or central processing unit 130a and memory hardware 130b, including read-only memory (ROM), random access memory (RAM), electrically programmable read-only memory (EPROM), a high-speed clock, analog-to-digital (A / D) and digital-to-analog (D / A) circuits, input / output circuits and devices (I / O), and appropriate signal conditioning and buffering circuits. Each control module 134, 136, 138, 132 has a set of control algorithms, including resident program instructions and calibrations stored in the memory hardware and executed to provide the corresponding functions of each computer. Information transmission between the various computers can be accomplished using the aforementioned network 150.

[0044] The control and state estimation algorithms in each control module 134, 136, 138, 132 are typically executed in preset loop cycles, such that each algorithm is executed at least once in each loop cycle. Algorithms stored in the non-volatile memory devices are executed by one of the central processing units and are operable to monitor inputs from the sensing devices and execute control and diagnostic routines to control the operation of the respective devices using preset calibrations. Loop cycles are typically executed at regular intervals, for example each 3.125, 6.25, 12.5, 25 and 100 milliseconds during engine and vehicle operation. Alternatively, algorithms may be executed in response to the occurrence of an event.

[0045] The actions described below occur during active operation of the vehicle, which includes periods of time when operation of the engine and electric motor is enabled by the vehicle operator, typically through an "on" action. Static periods include periods of time when operation of the engine and electric motor is disabled by the vehicle operator, typically through an "off" action. In response to operator actions captured by the UI 140, the monitoring HCM 132 and one or more other control modules 136 determine the desired transmission output torque To The selectively operable components of the vehicle drive system 100 are appropriately controlled and manipulated in response to operator demands. For example, in Figure 1 In the example shown, when the operator selects the forward drive range and manipulates the accelerator pedal or the brake pedal, the HCM 132 determines how and when the vehicle accelerates or decelerates. The HCM 132 also monitors the parametric states of the torque sources 102, 104 and determines the output of the transmission 106 required to achieve the desired acceleration or deceleration rate. Under the direction of the HCM 132, the vehicle drive system 100 operates within a range of output speeds from slow to fast to meet the operator demand.

[0046] Reference now Figure 2 , providing a coordinated torque output T of the vehicle torque sources 102 , 104 o A computer-implemented method 200 is provided. The method 200 may be provided as a set of instructions executed by one or more of the aforementioned control modules 132, 134, 136, 138 of the system controller 130 in response to one or more inputs 142, 144, 146, 148 received from the UI 140. In general, the method 200 provides a measure of receiving a driver input (e.g., an accelerator input 142) and evaluating the input to control the torque output at the torque source 102, 104, such as the electric motor 104 alone or the electric motor 104 in combination with the internal combustion engine 102. The method ensures that the higher efficiency torque source (e.g., the electric motor 104) is maximized before and during the start of the lower efficiency torque source (e.g., the internal combustion engine 102) to provide additional torque and meet the driver input. The method 200 allows for coordinated torque distribution between the two (or more) torque sources 102, 104 and optimizes catalyst light-off performance in the most efficient manner. Furthermore, the new method 200 allows for more efficient use of the torque sources 102 , 104 and results in improved emissions performance in applications with hybrid (electric plus ICE) torque sources.

[0047] In a first operation 204 , the system controller 130 outputs the torque T based on the requested torque. req and the available current torque source output torque T cur-avail Calculate the current torque source error T err For example, the vehicle drive system 100 may initially be operated in a steady state (eg, without acceleration) whereby the first electric motor 104 provides the full torque input T to the transmission 106. trans When the driver presses the accelerator, the system controller 130 receives or obtains the current torque source output T cur (Operation 206) and the requested torque output T req (Operation 208), and calculate the available current torque source output T cur-avail Relative to the requested torque output T reqerrors or deficiencies.

[0048] In operation 206 , the system controller 130 determines the available current torque source output T cur-avail , which corresponds to the total available torque output of the first electric motor 104. The available current torque source output T cur-avail It can include the instantaneous current torque source output T cur-inst Component 210 (which corresponds to the current torque output from the first electric motor 104) and the maximum current torque source output T cur-max Component 212 (which corresponds to the maximum available torque output that can be transmitted by the first electric motor 104 to the transmission 106 ).

[0049] In operation 204 , the system controller 130 also receives the requested driver torque T req , which corresponds to the calculated torque value required to satisfy one or more driver inputs 142 , 144 , 146 , 148 received from the UI 140 . For example, in operation 208 , the system controller 130 calculates the requested torque T associated with the accelerator pedal input 142 req , whereby the driver depresses the accelerator pedal to increase the power output (ie, speed) of the vehicle 10 . Requested torque T req Can be used as the requested vehicle speed S req and the requested acceleration A req The function is used to calculate the requested vehicle speed Sreq and the requested acceleration A req Based on the accelerator pedal input 142 and the current vehicle speed 214 (S) obtained from one or more vehicle speed sensors cur ) is determined. Using the requested torque T req and the available current torque source output T cur-avail , the system controller 130 calculates the current torque source error T err The magnitude of the torque T req and the available current torque source output T cur-avail In some examples, this calculation corresponds to the requested torque T req and the available current torque source output T cur-avail In other words, the calculation can be determined as the total calculated error measured or estimated over a period of time, rather than the instantaneous error at a given point in time.

[0050] In operation 216 , the system controller 130 evaluates the current torque source error T err Whether the torque source error threshold T is exceeded thresh , to determine whether to engage an additional torque source of the torque sources 102 , 104 . When the system controller 130 determines the current torque source error T err The torque source error threshold T is not exceededthresh , the system controller 130 ends the current iteration of the method 200 and returns to the first operation 204 to start a subsequent iteration of the method 200.

[0051] Conversely, when the system controller 130 determines the current torque source error T err Exceeding the torque source error threshold T thresh , the system controller 130 proceeds to operation 218 to activate the supplemental torque sources 102, 104. In operation 218, the axle torque request 133 corresponds to the current torque source error T associated with the current torque source 102, 104. err Required supplementary torque T supp The system controller 130 may be configured to prioritize the activation of the supplemental torque sources 102, 104 of the vehicle 10 based on the weighted or scored efficiency values ​​219 of the supplemental torque sources 102, 104. For example, in a vehicle 10 having a primary electric motor 104a, one or more supplemental electric motors 104b, and an internal combustion engine 102, the system controller 130 may be configured such that the one or more supplemental electric motors 104b have a higher efficiency score than the internal combustion engine 102 and are assigned a greater weight. Thus, when the current torque source error T err Exceeding the torque source error threshold T of the main electric motor 104a thresh When the system controller 130 starts the one or more supplemental electric motors 104 b before starting the internal combustion engine 102 .

[0052] Depending on the configuration of the vehicle (e.g., electric vehicle, hybrid electric vehicle), the supplemental torque sources 102, 104 may include an additional one of the electric motor 104b (e.g., in an electric vehicle or a hybrid vehicle having multiple electric motors) or the internal combustion engine 102 (e.g., in a hybrid vehicle). The system controller 130 performs a sub-operation 220 to determine whether to transmit the axle torque request 133 as an electric motor torque command 113 to (i) the other electric motor 104b, or as an internal combustion engine torque command 135 to (ii) the internal combustion engine 102.

[0053] In the event that the supplemental torque source is one of the supplemental electric motors 104 b (answer “no” at operation 220 ), the system controller 130 transmits the axle torque request 133 to the TPIM 112 , which generates the electric motor torque command 113 and activates the supplemental electric motor 104 b to immediately provide the requested supplemental torque T to the transmission 106 . req-supp In other words, when providing the requested supplementary torque T req-supp Previously, the supplemental electric motor 104b may not have required a ramp-up period.

[0054] Conversely, in the event that the supplemental torque source is the ICE 102 (a YES response at operation 220), the system controller 130 proceeds to operation 222 to generate the ICE torque command 135. Here, the ICE torque command 135 may include a ramp-up command 135a for providing the requested supplemental torque T to the driveline 108. req-supp Typically, the ramp-up command 135a includes parameters for operating the internal combustion engine 102 in an idle or low-load state to allow the internal combustion engine 102 to warm up to an optimized operating temperature (eg, to provide the requested supplemental torque T ) before transitioning to a loaded state. req-supp The duration and rate of the ramp-up period is determined by the system controller 130 as the torque source error T err For example, when the torque source error T err When the torque source error T is relatively large, the ECM 134 will instruct the internal combustion engine 102 to perform a relatively aggressive ramp-up period with a relatively short duration and a high ramp-up rate. In other words, when supplemental torque is needed immediately, the ramp-up period may be the minimum ramp-up period sufficient to warm up the internal combustion engine 102 to the threshold minimum operating temperature. Conversely, when the torque source error T is relatively large, the ECM 134 will instruct the internal combustion engine 102 to perform a relatively aggressive ramp-up period with a relatively short duration and a high ramp-up rate. In other words, when supplemental torque is needed immediately, the ramp-up period may be the minimum ramp-up period sufficient to warm up the internal combustion engine 102 to the threshold minimum operating temperature. err Relatively small, but still exceeds the torque source error threshold T thresh , the ECM 134 will instruct the internal combustion engine 102 to perform a relatively long ramp-up period at a low ramp-up rate, thereby allowing the internal combustion engine 102 to provide the supplemental requested torque T req-supp By implementing a ramp-up period, the application requests supplemental torque T req-supp Before and during this time, the internal combustion engine 102 operates at maximum efficiency.

[0055] In operation 224 , the system controller 130 calculates a total torque source error T for all starting torque sources 102 , 104 providing torque to the transmission. err-agg At operation 224 , the total torque source error T err-agg The calculation of the current torque source error T is similar to that performed in operation 204. err However, in operation 224, the system controller 130 calculates the supplemental torque T req-supp and the supplementary torque source output T supp-avail (which is the instantaneous torque T of the supplementary torque source provided by input 228 supp-inst and the maximum source torque T of the supplementary torque source supp-max The total torque source error T is calculated as a function of err-agg In other words, the total torque source error T err-agg Based on the total requested torque (T req +T req-supp ) and the total available torque provided by the starting torque source (T cur-avail +T supp-avail)

[0056] In operation 232 , the system controller 130 estimates the total torque source error T err-agg Whether the torque source error threshold T is exceeded thresh , if so, a subsequent torque evaluation 234 is performed with respect to a subsequent one of the supplemental torque sources 102, 104b. As indicated by the dashed lines, each torque evaluation 234 includes a respective iteration of operations 218, 220, 222, 224 associated with a subsequent one of the supplemental torque sources 102, 104b. Additional iterations of the torque evaluation 234 are performed for each available torque source 102, 104b until all supplemental torque sources 102, 104b are utilized.

[0057] The foregoing description has been provided for the purpose of illustration and description. It is not intended to be exhaustive or to limit the present disclosure. Individual elements or features of a particular configuration are generally not limited to that particular configuration, but where applicable, they are interchangeable and can be used in a selected configuration even if not specifically shown or described. This can also be varied in a variety of ways. Such variations should not be considered a departure from the present disclosure, and all such modifications are intended to be included within the scope of the present disclosure.

Claims

1. A computer-implemented method that, when executed by data processing hardware of a vehicle having a vehicle drive system and a plurality of torque sources connected to the vehicle drive system, causes the data processing hardware to perform operations comprising: instructing a first torque source of a plurality of torque sources to provide instantaneous torque to a vehicle drive system; receiving a requested torque output from a vehicle drive system; obtaining a first available torque source output of a first torque source; calculating a first torque error based on the requested torque output and a first available torque source output of the first torque source; determining whether the first torque error exceeds a torque error threshold; as well as When the first torque error exceeds a torque error threshold, a first supplemental torque source from among the plurality of torque sources is activated to provide a first supplemental torque output to the vehicle drive system.

2. The method according to claim 1, wherein: The operations also include: obtaining a supplemental available torque source output of the first supplemental torque source; calculating a total torque error based on the requested torque output and the supplemental available torque source output; determining whether the total torque error exceeds a torque error threshold; and When the total torque error exceeds a torque error threshold, a second supplemental torque source among the plurality of torque sources is instructed to provide a second supplemental additional torque output to the vehicle drive system.

3. The method according to claim 1, wherein: The operations also include determining the requested torque output based on a measured vehicle speed and a requested vehicle speed.

4. The method according to claim 1, wherein: The first available torque source output includes at least one of a momentary current torque source output component and a maximum current torque source output component.

5. The method according to claim 1, wherein: Activating a first supplemental torque source among the plurality of torque sources includes activating an available torque source having a highest efficiency score.

6. The method according to claim 1, wherein: The plurality of torque sources may include one or more electric motors or internal combustion engines.

7. The method according to claim 1, wherein: The operations further include instructing the first supplemental torque source to perform a ramp-up period prior to providing the first supplemental torque output.

8. The method according to claim 7, wherein: The ramp-up period includes operating the first supplemental torque source in a no-load state prior to providing the first supplemental torque output.

9. A control system for a vehicle having a vehicle drive system and a plurality of torque sources connected to the vehicle drive system, the control system comprising: Data processing hardware; and Memory hardware in communication with the data processing hardware, the memory hardware storing instructions that, when executed on the data processing hardware, cause the data processing hardware to perform operations including: instructing a first torque source of a plurality of torque sources to provide instantaneous torque to a vehicle drive system; receiving a requested torque output from a vehicle drive system; obtaining a first available torque source output of a first torque source; calculating a first torque error based on the requested torque output and a first available torque source output of the first torque source; determining whether the first torque error exceeds a torque error threshold; as well as When the first torque error exceeds a torque error threshold, a first supplemental torque source from among the plurality of torque sources is activated to provide a first supplemental torque output to the vehicle drive system.

10. A computer-implemented method that, when executed by data processing hardware of a vehicle having a vehicle drive system and a plurality of torque sources connected to the vehicle drive system, causes the data processing hardware to perform operations comprising: instructing a first torque source of a plurality of torque sources to provide instantaneous torque to a vehicle drive system; receiving a requested torque output from a vehicle drive system; obtaining a first available torque source output of a first torque source; calculating a first torque error based on the requested torque output and a first available torque source output of the first torque source; determining whether the first torque error exceeds a torque error threshold; When the first torque error exceeds a torque error threshold, obtaining an efficiency score for the one or more supplemental torque sources; as well as A first supplemental torque source having a highest efficiency score is selected from the plurality of supplemental torque sources to provide a first supplemental torque output to the vehicle drive system.

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