Method and system for determining driver demand

Abstract

This disclosure provides a method and system for operating a powertrain of a hybrid vehicle comprising an internal combustion engine, an electric motor, and a described transmission. In one example, the accelerator pedal position provides a basis for requesting vehicle acceleration, and the vehicle wheel torque is determined based on the requested vehicle acceleration.

Description

Technical Field

[0001] This invention generally relates to methods and systems for controlling the torque of a hybrid vehicle's powertrain. These methods and systems may be particularly suitable for hybrid vehicles that include an engine and a rear-wheel drive motor. Background Technology

[0002] A driver can request torque from the vehicle via the accelerator pedal. The position of the accelerator pedal directly translates into the requested engine torque. The requested engine torque can be provided by opening or closing the throttle, adjusting spark timing, and adjusting the amount of fuel injected into the engine. The engine torque can be output to the input of the transmission. The transmission can transmit torque from the engine to the axles, and the axles can transmit torque from the engine to the vehicle wheels. However, hybrid vehicles may include both an electric motor and an engine for providing the requested torque. The requested torque can be provided partly by the engine and partly by the electric motor. The torque distribution provided via the engine and electric motor can be responsive to battery operating conditions, the level of torque requested by the driver, and other parameters. Furthermore, the driver's requested torque can be provided by a simple sum of the engine torque and the electric motor torque when both engine and electric motor torques are provided to the transmission input shaft. However, for hybrid vehicles with an electric motor located downstream of the transmission in the positive torque flow direction from the powertrain or drivetrain to the vehicle wheels, the driver's demand may not be a simple sum of the engine output torque and the electric motor torque due to the gears and clutches in the drivetrain. Therefore, it may be desirable to provide a method for determining the desired engine torque output and desired electric motor output that meet the driver's needs, even when the drivetrain torque source is separated by drivetrain components including gears and clutches. Summary of the Invention

[0003] The inventors of this paper have recognized the above-mentioned problems and have developed a method for operating a powertrain, which includes providing wheel torque in response to a desired vehicle acceleration, the desired vehicle acceleration being responsive to the accelerator pedal position and the current vehicle speed.

[0004] By determining the desired vehicle acceleration in response to accelerator pedal position and vehicle speed, the desired wheel torque for providing that desired vehicle acceleration can be determined. The desired wheel torque can then be divided into large or small portions and distributed to various torque sources in the drivetrain. The torque of the torque sources can be adjusted based on the components between the wheels and the torque sources, thereby providing the desired wheel torque and vehicle acceleration. For example, if the desired wheel torque is 300 N-m and 100 N-m is allocated to or provided by the electric motor, then the electric motor torque can be adjusted such that the electric motor torque multiplied by the final drive ratio equals 100 N-m. If the remaining 200 N-m of the wheel torque is allocated to or provided by the engine, then the engine torque can be adjusted such that the engine output torque multiplied by the transmission gear ratio and the final drive ratio equals 200 N-m. In this way, even for a hybrid drivetrain with distributed torque sources, the torque provided by the torque sources can be adjusted to provide the requested driver demand.

[0005] According to the present invention, a method for operating a transmission system is provided, the method comprising:

[0006] Wheel torque is provided in response to desired vehicle acceleration, which is determined by the accelerator pedal position and the current vehicle speed.

[0007] According to one embodiment of the invention, wheel torque is provided via an engine and an electric motor in this method.

[0008] According to one embodiment of the invention, the method further includes outputting the desired vehicle acceleration from a lookup table referenced via the accelerator pedal position and the current vehicle speed.

[0009] According to one embodiment of the invention, the method further includes converting the desired vehicle acceleration into wheel torque.

[0010] According to one embodiment of the invention, the method of converting desired vehicle acceleration into wheel torque includes adjusting an estimated value of the wheel torque in response to the drivetrain moment of inertia, wherein the drivetrain moment of inertia changes with the vehicle operating mode.

[0011] According to one embodiment of the invention, the method of converting the desired vehicle acceleration into wheel torque includes adjusting the estimated value of the wheel torque in response to the vehicle's frontal area and the vehicle's mass.

[0012] According to one embodiment of the invention, the method of converting the desired vehicle acceleration into wheel torque includes adjusting the estimated value of the wheel torque in response to the rolling resistance coefficient of the wheel.

[0013] According to the present invention, a method for operating a transmission system is provided, comprising:

[0014] Wheel torque is provided in response to desired vehicle acceleration, which is responsive to accelerator pedal position, current vehicle speed, and currently engaged transmission gear.

[0015] According to one embodiment of the present invention, the desired vehicle acceleration in the method is a portion of the vehicle acceleration rate under the first gear and a portion of the vehicle acceleration under the second gear.

[0016] According to one embodiment of the present invention, in the method, a portion of the vehicle acceleration rate under the first gear and a portion of the vehicle acceleration under the second gear respond to the tuning ratio.

[0017] According to one embodiment of the present invention, the blending ratio in this method is based on the transmission ratio.

[0018] According to one embodiment of the invention, the desired vehicle acceleration in the method also responds to the transmission gear ratio.

[0019] According to one embodiment of the invention, the method further includes referencing a lookup table via the accelerator pedal position, the current vehicle speed, and the currently engaged transmission gear.

[0020] According to one embodiment of the present invention, the method outputs the vehicle acceleration under the desired transmission gear by a lookup table.

[0021] According to the present invention, a system is provided, the system comprising:

[0022] engine;

[0023] An integrated starter / generator connected to the engine;

[0024] The transmission includes a first input clutch, a second input clutch, a first input shaft and a second input shaft, a first countershaft selectively connected to the first input shaft, a second countershaft selectively connected to the second input shaft, a plurality of gears, and an output shaft connected to the first countershaft and the second countershaft;

[0025] A rear-wheel drive system, comprising a rear axle and an electric motor connected to a transmission via a drive shaft; and

[0026] The controller includes executable instructions stored in a non-transitory memory, which are used to provide wheel torque in response to desired vehicle acceleration, which is responsive to accelerator pedal position, current vehicle speed, and currently engaged transmission gear.

[0027] According to one embodiment of the invention, the system further includes additional instructions for providing wheel torque via a motor included in the rear-wheel drive unit.

[0028] According to one embodiment of the invention, the system further includes additional instructions for adjusting to provide wheel torque via the engine.

[0029] According to one embodiment of the present invention, the desired vehicle acceleration in the system is a portion of the vehicle acceleration rate under the first gear and a portion of the vehicle acceleration under the second gear.

[0030] According to one embodiment of the invention, the system further includes additional instructions for referencing a lookup table via accelerator pedal position, current vehicle speed, and currently engaged transmission gear.

[0031] According to one embodiment of the invention, the system further includes additional instructions for converting the desired vehicle acceleration into wheel torque.

[0032] This specification offers several advantages. Specifically, the method consistently responds to driver demands even under different hybrid vehicle operating modes. Furthermore, the method allows for consistent torque delivery to the driver's desired torque, even with varying drivetrain configurations. Additionally, the method reduces drivetrain torque disturbances because it takes into account drivetrain inertia in response to hybrid vehicle operating modes.

[0033] It should be understood that the above description of the invention is provided to present, in a simplified form, the selected concepts further described in the detailed embodiments. This does not imply identification of the key or essential features of the claimed subject matter, the scope of which is uniquely defined by the claims following the detailed embodiments. Furthermore, the claimed subject matter is not limited to embodiments that address any of the shortcomings mentioned above or in any part of this disclosure. Attached Figure Description

[0034] Figure 1A This is a schematic diagram of the powertrain of a hybrid vehicle;

[0035] Figure 1B This is a simplified diagram of the engine in the powertrain of a hybrid vehicle;

[0036] Figure 2 This is a schematic diagram of the powertrain of a hybrid vehicle, which includes controllers for various powertrain components.

[0037] Figure 3 This is a schematic diagram of a dual-clutch transmission located in the powertrain of a hybrid vehicle;

[0038] Figure 4 This is a flowchart of a method for determining the desired wheel torque;

[0039] Figure 5 It is based on Figure 4The method provides a predictive curve of the transmission system's operating sequence; and

[0040] Figure 6 This is a flowchart of a method for determining the desired vehicle acceleration; and

[0041] Figure 7 It is based on Figure 6 The method is a predictive curve of the transmission system's operating sequence. Detailed Implementation

[0042] The following embodiments relate to systems and methods for operating the powertrain of a hybrid vehicle. Figure 1A-3 An exemplary hybrid vehicle system is shown, which includes a drivetrain having a motor, an integrated starter / generator, a dual-clutch transmission, and a rear-wheel drive unit having an electric motor disposed downstream of the dual-clutch transmission. Figure 4 The diagram illustrates a method for determining the desired wheel torque, which is not limited to a specific drivetrain configuration. Figure 5 The text shows the data based on... Figure 4 The method provides a predictive transmission system operating sequence. Figure 6 The diagram shows a flowchart of a method for determining the desired vehicle acceleration. Figure 7 The text shows the data based on... Figure 6 The method of transmission system operation sequence.

[0043] Figure 1A An exemplary vehicle propulsion system 100 for vehicle 121 is shown. The vehicle propulsion system 100 includes at least two power sources, including an internal combustion engine 110 and an electric motor 120. The electric motor 120 can be configured to utilize or consume energy different from that of the engine 110. For example, the engine 110 can consume liquid fuel (e.g., gasoline) to produce engine output, while the electric motor 120 can consume electrical energy to produce motor output. Therefore, a vehicle having the propulsion system 100 can be referred to as a hybrid electric vehicle (HEV). Throughout... Figure 1A The description uses solid lines to show the mechanical connections between the components and dashed lines to show the electrical connections between the components.

[0044] The vehicle propulsion system 100 has a front axle (not shown) and a rear axle 122. In some examples, the rear axle may include two half-shafts, such as a first half-shaft 122a and a second half-shaft 122b. The vehicle propulsion system 100 also has front wheels 130 and rear wheels 131. The rear axle 122 is connected to an electric motor 120 and a transmission 125 via a driveshaft 129. The rear axle 122 can be driven purely electrically and solely by the electric motor 120 (e.g., electric drive or propulsion mode where the engine does not burn air and fuel or rotate), by the electric motor 120 and the engine 110 (e.g., parallel mode) in a hybrid manner, or solely by the engine 100 (e.g., engine propulsion mode) in a purely internal combustion engine mode. A rear-wheel drive unit 136 can transmit power from the engine 110 or the electric motor 120 to the axle 122, causing the drive wheels 131 to rotate. The rear-wheel drive unit 136 may include a gear set and one or more clutches for disengaging the transmission 125 and the electric motor 120 from the wheels 131. The rear-wheel drive unit 136 may include a motor 120 and a shaft 122.

[0045] Transmission 125 Figure 1A The transmission 125 is shown as connected between the engine 110 and the electric motor 120, which is distributed to the rear axle 122. In one example, the transmission 125 is a dual-clutch transmission (DCT). In the example where the transmission 125 is a DCT, the DCT may include a first clutch 126, a second clutch 127, and a gearbox 128. The DCT 125 outputs torque to the drive shaft 129, thereby providing torque to the wheels 131. Reference will be made below. Figure 3 In further detail, the transmission 125 can shift gears by selectively disengaging and engaging the first clutch 126 and the second clutch 127.

[0046] The motor 120 can receive power from the on-board energy storage device 132. Furthermore, the motor 120 can provide a generator function for converting engine output or the vehicle's kinetic energy into electrical energy, which can be stored in the energy storage device 132 for subsequent use by the motor 120, the integrated starter / generator 142, or optionally the integrated starter / generator 171. The first inverter system controller (ISC1) 134 can convert the alternating current generated by the motor 120 into direct current for storage in the energy storage device 132, and vice versa.

[0047] In some examples, energy storage device 132 may be configured to store electrical energy that can be supplied to other electrical loads (other than the motor) residing on the vehicle, including cabin heating and air conditioning systems, engine starting systems, headlights, cabin audio and video systems, etc. As a non-limiting example, energy storage device 132 may include one or more batteries and / or capacitors.

[0048] The control system 14 can communicate with one or more of the following: engine 110, electric motor 120, energy storage device 132, integrated starter / generator 142, optional integrated starter / generator 171, transmission 125, etc. The control system 14 can receive sensor feedback information from one or more of the following: engine 110, electric motor 120, energy storage device 132, integrated starter / generator 142, optional integrated starter / generator 171, transmission 125, etc. Furthermore, the control system 14 can send control signals to one or more of the following in response to this sensor feedback: engine 110, electric motor 120, energy storage device 132, transmission 125, etc. The control system 14 can receive instructions from the operator 102 or the autonomous controller regarding the output of the vehicle propulsion system. For example, the control system 14 can receive sensor feedback from a pedal position sensor 194 that communicates with pedal 192. Pedal 192 can schematically refer to the accelerator pedal. Similarly, control system 14 can receive instructions for vehicle braking requested by the operator 102 or an autonomous controller. For example, control system 14 can receive sensing feedback from pedal position sensor 157, which communicates with brake pedal 156.

[0049] As indicated by arrow 184, the energy storage device 132 can periodically receive electrical energy from a power source 180 (e.g., a stationary power grid) located outside the vehicle (e.g., not part of the vehicle). As a non-limiting example, the vehicle propulsion system 100 can be configured for a plug-in hybrid electric vehicle (PHEV), whereby electrical energy can be supplied from the power source 180 to the energy storage device 132 via the electric transmission cable 182. During recharging operation of the energy storage device 132 by the power source 180, the electric transmission cable 182 can electrically connect the energy storage device 132 and the power source 180. In some examples, the power source 180 can be connected at an input port 150. Furthermore, in some examples, a charging status indicator 151 can display the charging status of the energy storage device 132.

[0050] In some examples, electrical energy from power source 180 can be received by charger 152. For example, charger 152 can convert alternating current (AC) from power source 180 into direct current (DC) for storage in energy storage device 132. Furthermore, DC / DC converter 153 can convert the DC source from charger 152 from one voltage to another. In other words, DC / DC converter 153 can act as a type of power converter.

[0051] When the vehicle propulsion system is operating to propel the vehicle, the electric transmission cable 182 can be disconnected between the power source 180 and the energy storage device 132. The control system 14 can identify and / or control the amount of electrical energy stored in the energy storage device, which can be referred to as the state of charge (SOC).

[0052] In other examples, where electrical energy can be wirelessly received from power source 180 at energy storage device 132, the electric transmission cable 182 may be omitted. For example, energy storage device 132 may receive electrical energy from power source 180 via one or more of electromagnetic induction, radio waves, and electromagnetic resonance. Therefore, it should be understood that any suitable method can be used to recharge energy storage device 132 from a power source not part of the vehicle. In this way, motor 120 can propel the vehicle by utilizing energy other than the fuel used by engine 110.

[0053] The energy storage device 132 includes an energy storage device controller 139 and a power distribution module 138. The energy storage device controller 139 can provide balanced charge among energy storage elements (e.g., battery cells) and communicate with other vehicle controllers (e.g., controller 12). The power distribution module 138 controls the flow of power into and out of the energy storage device 132.

[0054] The vehicle propulsion system 100 may also include an ambient temperature / humidity sensor 198, and sensors specifically designed to indicate the vehicle's occupancy status, such as an onboard camera 105, a seat load sensor 107, and a door sensing technology device 108. The vehicle system 100 may also include an inertial sensor 199. The inertial sensor 199 may include one or more of the following sensors: a longitudinal sensor, a lateral sensor, a vertical sensor, a yaw sensor, a roll sensor, and a pitch sensor (e.g., an accelerometer). The axes of yaw, pitch, roll, lateral acceleration, and longitudinal acceleration are shown in the figure. As an example, the inertial sensor 199 may be connected to the vehicle's constraint control module (RCM) (not shown), which contains subsystems of the control system 14. The control system may adjust engine output and / or wheel brakes in response to the sensor 199 to increase vehicle stability. In another example, the control system may adjust the active suspension system 111 in response to input from the inertial sensor 199. The active suspension system 111 may include an active suspension system with hydraulic, electrical, and / or mechanical components, and an active suspension system that controls vehicle height based on a single angle (e.g., vehicle height controlled at each of the four corners), vehicle height based on individual axles (e.g., front and rear axle vehicle heights), or a uniform vehicle height for the entire vehicle. Data from the inertial sensor 199 may also be transmitted to the controller 12, or alternatively, the sensor 199 may be electrically connected to the controller 12.

[0055] One or more tire pressure monitoring sensors (TPMS) can be attached to the tires of one or more wheels in a vehicle. For example, Figure 1A A tire pressure sensor 197 is shown, which is connected to wheel 131 and configured to monitor the pressure in the tire of wheel 131. Although not explicitly shown, it should be understood that... Figure 1A Each of the four tires indicated may include one or more tire pressure sensors 197. Furthermore, in some examples, the vehicle propulsion system 100 may include a pneumatic control unit 123. The pneumatic control unit may receive information about tire pressure from the tire pressure sensors 197 and transmit the tire pressure information to the control system 14. Based on the tire pressure information, the control system 14 may command the pneumatic control unit 123 to inflate or deflate the tires of the wheels. Although not explicitly shown, it should be understood that the pneumatic control unit 123 can be used to... Figure 1AThe system inflates or deflates any of the associated tires on the four wheels shown. For example, in response to an indication of decreased tire pressure, the control system 14 can command the pneumatic control system unit 123 to inflate one or more tires. Alternatively, in response to an indication of increased tire pressure, the control system 14 can command the pneumatic control system unit 123 to deflate one or more tires. In both examples, the pneumatic control system unit 123 can be used to inflate or deflate tires to their optimal tire pressure rating, which can extend tire life.

[0056] One or more wheel speed sensors (WSS) 195 may be connected to one or more wheels of the vehicle propulsion system 100. The wheel speed sensors can detect the rotational speed of each wheel. Such an example of a WSS may include a permanent magnet type sensor.

[0057] The vehicle propulsion system 100 may also include an accelerometer 20. The vehicle propulsion system 100 may also include an inclinometer 21.

[0058] The vehicle propulsion system 100 may also include a starter 140. The starter 140 may include an electric motor, a hydraulic motor, etc., and may be used to rotate the engine 110 so as to start the engine 110 under its own power.

[0059] The vehicle propulsion system 100 may also include a brake system control module (BSCM) 141. In some examples, the BSCM 141 may include an anti-lock braking system or an anti-skid braking system, such that the wheels (e.g., 130, 131) can maintain traction contact with the road surface during braking based on driver input. Maintaining traction contact with the road surface during braking can thus prevent wheel lock-up and thereby prevent slippage. In some examples, the BSCM may receive input from a wheel speed sensor 195.

[0060] The vehicle propulsion system 100 may also include a belt-driven integrated starter / generator (BISG) 142 or an optional integrated starter / generator. The BISG and / or the optional integrated starter / generator can generate electricity while the engine 110 is running, wherein the generated electricity can be used to power electrical devices and / or charge the on-board storage device 132. Figure 1AAs shown, the second inverter system controller (ISC2) 143 can receive AC power from the BISG 142 or optional integrated starter / generator 171, and can convert the AC power generated by the BISG 142 or optional integrated starter / generator 171 into DC power for storage in the energy storage device 132. The integrated starter / generator 142 or optional integrated starter / generator 171 can also provide torque to the engine 110 during engine start-up or other conditions to supplement engine torque. The optional integrated starter / generator 171 can be directly connected to the engine 110 via the engine crankshaft 40B.

[0061] The vehicle propulsion system 100 may also include a power distribution box (PDB) 144. The PDB 144 can be used to route power supplies throughout the various circuits and accessories in the vehicle's electrical system.

[0062] The vehicle propulsion system 100 may also include a high current fuse box (HCFB) 145, and may contain various fuses (not shown) for protecting the wiring and electrical components of the vehicle propulsion system 100.

[0063] The vehicle propulsion system 100 may also include a motor electronics coolant pump (MECP) 146. The MECP 146 can be used to circulate coolant to dissipate heat generated by at least the motor 120 and electronic systems of the vehicle propulsion system 100. For example, the MECP may receive electricity from an onboard energy storage device 132.

[0064] Controller 12 may form part of control system 14. In some examples, controller 12 may be a single controller for the vehicle. Control system 14 is shown receiving information from multiple sensors 16 (various examples of which are described herein) and sending control signals to multiple actuators 81 (various examples of which are described herein). As an example, sensors 16 may include tire pressure sensor 197, wheel speed sensor 195, ambient temperature / humidity sensor 198, vehicle camera 105, seat load sensor 107, door sensing technology device 108, inertial sensor 199, etc. In some examples, sensors associated with engine 110, transmission 125, motor 120, etc., may transmit information about various states of engine, transmission, and motor operation to controller 12, as shown in reference [reference needed]. Figure 1B , Figure 2 ,as well as Figure 3 We will discuss this in more detail later.

[0065] The vehicle propulsion system 100 may also include a positive temperature coefficient (PTC) heater 148. For example, the PTC heater 148 may comprise a ceramic material such that when the resistance is low, the ceramic material can accept a large current, which can cause the ceramic element to heat up rapidly. However, as the element heats up and reaches a threshold temperature, the resistance can become very high, and therefore it may not continue to generate much heat. For this reason, the PTC heater 148 can be self-adjusting and can have a good overheat protection rating.

[0066] The vehicle propulsion system 100 may also include an air conditioning compressor module 149 for controlling an electric air conditioning compressor (not shown).

[0067] The vehicle propulsion system 100 may also include a vehicle auditory sound emitter (VASP) 154 for pedestrians. For example, the VASP 154 may be configured to generate an audible sound via a sound emitter 155. In some examples, the audible sound generated by the VASP 154, which communicates with the sound emitter 155, may be activated in response to a vehicle operator triggering the sound, or automatically activated in response to an engine speed below a threshold or the detection of a pedestrian.

[0068] The vehicle propulsion system 100 may also include an in-vehicle navigation system 17 (e.g., a Global Positioning System) located on the dashboard 19, which the vehicle operator can interact with. The navigation system 17 may include one or more position sensors for assisting in estimating the vehicle's location (e.g., geographic coordinates). For example, the in-vehicle navigation system 17 may receive signals from GPS satellites (not shown) and identify the vehicle's geographic location using these signals. In some examples, the geographic coordinates may be transmitted to the controller 12.

[0069] The dashboard 19 may also include a display system 18 configured to display information to a vehicle operator. As a non-limiting example, the display system 18 may include a touchscreen, a human-machine interface (HMI), or a display that allows the vehicle operator to view graphical information and input commands. In some examples, the display system 18 may be wirelessly connected to the Internet (not shown) via a controller (e.g., 12). Therefore, in some examples, the vehicle operator may be able to communicate with websites or software applications (apps) via the display system 18.

[0070] The dashboard 19 may also include an operator interface 15 through which a vehicle operator can adjust the vehicle's operating status. Specifically, the operator interface 15 may be configured to start and / or terminate the operation of the vehicle's drivetrain (e.g., engine 110, BISG 142, DCT 125, electric motor 120) based on operator input. Various exemplary operator ignition interfaces 15 may include interfaces such as active keys that require insertion into the operator ignition interface 15 to start the engine 110 and start the vehicle, or can be removed to turn off the engine 110 and shut down the vehicle. Other examples may include passive keys communicatively connected to the operator ignition interface 15. Passive keys may be configured as electronic keycards or smart keys that operate the vehicle engine 110 without needing to be inserted into or removed from the ignition interface 15. Of course, the passive key may need to be located inside or near the vehicle (e.g., within a threshold distance of the vehicle). Another example may additionally or optionally use a start / stop button that is manually pressed by the operator to start or stop the engine 110 and to start or stop the vehicle. In other examples, a remote computing device (not shown) may initiate remote engine start; the remote computing device may be a cellular phone or a smartphone-based system, wherein the user's cellular phone sends data to a server, and the server communicates with the vehicle controller 12 to start the engine.

[0071] refer to Figure 1B The diagram shows a detailed view of an internal combustion engine 110, which includes multiple cylinders, one of which... Figure 1B As shown in the diagram, engine 110 is controlled by an electronic engine controller 111B. Engine 110 includes a combustion chamber 30B and cylinder walls 32B, in which piston 36B is disposed and connected to crankshaft 40B. Combustion chamber 30B is shown as communicating with intake manifold 44B and exhaust manifold 48B via corresponding intake valve 52B and exhaust valve 54B. Each intake valve and exhaust valve can be operated by intake cam 51B and exhaust cam 53B. The position of intake cam 51B can be determined by intake cam sensor 55B. The position of exhaust cam 53B can be determined by exhaust cam sensor 57B. Intake cam 51B and exhaust cam 53B can move relative to crankshaft 40B. Intake valves can be deactivated and held closed by intake valve deactivation mechanism 59B. Exhaust valves can be deactivated and held closed by exhaust valve deactivation mechanism 58B.

[0072] Fuel injector 66B is shown configured to inject fuel directly into cylinder 30B, which is direct injection known to those skilled in the art. Alternatively, fuel can be injected into the intake port, which is intake port injection known to those skilled in the art. Fuel injector 66B delivers liquid fuel in proportion to the pulse width of a signal from engine controller 111B. Fuel is delivered to fuel injector 66B via fuel system 175B, which includes a canister and a pump. Additionally, intake manifold 44B is shown in communication with an optional electronic throttle valve 62B (e.g., a butterfly valve), which adjusts the position of throttle plate 64B to control airflow from air filter 43B and intake port 42B to intake manifold 44B. Throttle valve 62B adjusts airflow from air filter 43B in engine intake port 42B to intake manifold 44B. In some examples, the throttle valve 62B and the throttle plate 64B can be positioned between the intake valve 52B and the intake manifold 44B, such that the throttle valve 62B is a port throttle valve.

[0073] Distributorless ignition system 88B responds to engine controller 111B by providing an ignition spark to combustion chamber 30B via spark plug 92B. Wide-range exhaust oxygen (UEGO) sensor 126B is shown connected to exhaust manifold 48B upstream of catalytic converter 70B along the direction of exhaust flow. Alternatively, dual-state exhaust oxygen sensor may replace UEGO sensor 126B.

[0074] In one example, converter 70B may include multiple catalyst bricks. In another example, multiple emission control devices may be used, each having multiple bricks. In one example, converter 70B may be a ternary catalyst.

[0075] exist Figure 1BThe engine controller 111B shown is a typical microcomputer, which includes: a microprocessor unit (CPU) 102B, input / output ports (I / O) 104B, read-only memory (ROM) 106B (e.g., non-transitory memory), random access memory (RAM) 108B, keep-alive memory (KAM) 110B, and a conventional data bus. Other controllers mentioned herein may have similar processor and memory configurations. The engine controller 111B is shown to receive various signals from sensors connected to the engine 110, including, in addition to those previously discussed, the following: engine coolant temperature (ECT) from temperature sensor 112B connected to cooling manifold 114B; engine manifold pressure (MAP) measurement from pressure sensor 122B connected to intake manifold 44B; engine position from Hall effect sensor 118B sensing crankshaft 40B position; mass of air entering the engine from sensor 120B; and throttle position measurement from sensor 58B. The air pressure processed by the engine controller 111B can also be sensed (sensor not shown). In a preferred aspect of this specification, the engine position sensor 118B generates a predetermined number of equidistant pulses for each revolution of the crankshaft, through which the engine speed (RPM) can be determined. The engine controller 111B can receive input from the human / machine interface 115B (e.g., a button or touchscreen display).

[0076] During operation, each cylinder in engine 110 typically undergoes a four-stroke cycle: this cycle includes an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke. Generally, during the intake stroke, the exhaust valve 54B is closed, and the intake valve 52B is open. Air is introduced into combustion chamber 30B through intake manifold 44B, and piston 36B moves to the bottom of the cylinder to increase the volume within combustion chamber 30B. The position of piston 36B near the bottom of the cylinder and at the end of its stroke (e.g., when combustion chamber 30B is at its maximum volume) is generally referred to by those skilled in the art as bottom dead center (BDC). During the compression stroke, intake valve 52B and exhaust valve 54B are closed. Piston 36B moves toward the cylinder head to compress the air within combustion chamber 30B. The position of piston 36B at the end of its stroke and closest to the cylinder head (e.g., when combustion chamber 30B is at its minimum volume) is generally referred to by those skilled in the art as top dead center (TDC). In the process referred to below as injection, fuel is introduced into the combustion chamber. In the process referred to below as ignition, the injected fuel is ignited by a known ignition device such as spark plug 92B, resulting in combustion. During the expansion stroke, the expanding gas pushes piston 36B back to BDC. Crankshaft 40B converts the piston motion into rotational torque of the crankshaft. Finally, during the exhaust stroke, exhaust valve 54B opens to release the combusted air-fuel mixture into exhaust manifold 48B, and piston returns to TDC. It should be noted that the above is only illustrated by way of example, and the opening and / or closing timing of the intake and exhaust valves can be varied, for example, to provide positive or negative valve overlap, delay intake valve closing, or various other examples.

[0077] Figure 2 It is a block diagram of a vehicle 121 including a powertrain or transmission system 200. Figure 2 The power transmission system includes Figure 1A-1B The engine 110 shown. Figure 2 and Figure 1AOther components are indicated by the same reference numerals and will be discussed in detail below. The powertrain 200 is shown as including a vehicle system controller 12, an engine controller 111B, an electric motor controller 252, a transmission controller 254, an energy storage device controller 253, and a brake controller 141 (also referred to herein as the brake system control module). The controllers can communicate via a controller area network (CAN) 299. Each controller can provide information to the other controllers, such as torque output limits (e.g., not exceeding the torque output of the controlled device or component), torque input limits (e.g., not exceeding the torque input of the controlled device or component), torque output of the controlled device, sensor and actuator data, and diagnostic information (e.g., information about a deteriorated transmission, information about a deteriorated engine, information about a deteriorated electric motor, and information about a deteriorated brake). Furthermore, the vehicle system controller 12 can provide commands to the engine controller 111B, the electric motor controller 252, the transmission controller 254, and the brake controller 141 to fulfill driver input requests and other requests based on vehicle operating conditions.

[0078] For example, the vehicle system controller 12 may request a desired wheel torque or wheel power level in response to the driver releasing the accelerator pedal and the vehicle speed decreasing, in order to provide the desired vehicle deceleration rate. The vehicle system controller 12 requests a first braking torque from the motor controller 252 and a second braking torque from the brake controller 141 to provide the desired wheel torque, which provides the desired braking torque at the vehicle wheels 131.

[0079] In other examples, the division of the control powertrain system may differ. Figure 2 The division is shown. For example, a single controller can replace the vehicle system controller 12, engine controller 111B, motor controller 252, transmission controller 254, and brake controller 141. Alternatively, the vehicle system controller 12 and engine controller 111B can be a single device, while the motor controller 252, transmission controller 254, and brake controller 141 can be separate controllers.

[0080] In this example, the powertrain 200 may be powered by an engine 110, and / or an electric motor 120, and optionally an integrated starter / generator 171. In other examples, the engine 110 may be omitted. The engine 110 may be started using an engine starter (e.g., starter 140), via a belt-driven integrated starter / generator (BISG) 142 or optionally an integrated starter / generator 171, or via the electric motor 120. The electric motor 120 (e.g., a high-voltage motor operating at greater than 30 volts) is also referred to herein as an electric motor, generator, and / or generator. Furthermore, the torque of the engine 110 may be adjusted by a torque actuator 204, such as a fuel injector, throttle valve, etc.

[0081] BISG142 is mechanically connected to engine 110 via belt 231. BISG142 can be connected to either crankshaft (not shown) or camshaft (not shown). BISG142 can operate as a motor when powered by an energy storage device 132 (also referred to herein as on-board energy storage device 132). Alternatively, BISG142 can also operate as a generator supplying power to the energy storage device 132.

[0082] The drivetrain 200 includes an engine 110 mechanically connected to a dual-clutch transmission (DCT) 125 via a crankshaft 40B. The DCT 125 includes a first clutch 126, a second clutch 127, and a gearbox 128. The DCT 125 outputs torque to a shaft 129 to provide torque to wheels 131. A transmission controller 254 selectively disengages and engages the first clutch 126 and the second clutch 127 to shift gears in the DCT 125.

[0083] The gearbox 128 may include multiple gears. For example, one clutch of the first clutch 126 may control odd-numbered gears 261 (e.g., the first gear, the third gear, the fifth gear, and the reverse gear), while another clutch, such as the second clutch 127, may control even-numbered gears 262 (e.g., the second gear, the fourth gear, and the sixth gear). By utilizing such an arrangement, gears can be changed without interrupting the power flow from the engine 110 to the dual-clutch transmission 125.

[0084] The motor 120 can operate in regenerative mode to provide torque to the powertrain 200 or convert the powertrain torque into electrical energy for storage in the energy storage device 132. Additionally, the motor 120 can convert the vehicle's kinetic energy into electrical energy for storage in the energy storage device 132. The motor 120 communicates electrically with the energy storage device 132. The motor 120 has a higher... Figure 1AThe starter shown (e.g., 140) or BISG142 has a higher output torque capacity. Furthermore, the motor 120 directly drives the powertrain 200, or is directly driven by the powertrain 200.

[0085] The energy storage device 132 (e.g., a high-voltage battery or power source) can be a battery, capacitor, or inductor. The motor 120 is driven by the rear-wheel drive device 136. Figure 1A The gear set (shown in the diagram) is mechanically connected to the wheel 131 and the dual-clutch transmission. The motor 120 can supply positive or negative torque to the power transmission system 200 by operating as a motor or generator according to the instructions of the motor controller 252.

[0086] Furthermore, friction can be applied to wheel 131 by engaging friction wheel brake 218. In one example, friction wheel brake 218 can be engaged in response to a driver pressing their foot on the brake pedal (e.g., pedal 192) and / or in response to a command within brake controller 141. Additionally, brake controller 141 can apply brake 218 in response to information and / or requests from vehicle system controller 12. Similarly, friction applied to wheel 131 can be reduced by disengaging wheel brake 218 in response to a driver releasing their foot from the brake pedal, a brake controller command, and / or a vehicle system controller command and / or information. For example, as part of an automatic engine stop process, vehicle brakes can apply friction to wheel 131 via controller 141.

[0087] The vehicle system controller 12 can also transmit vehicle suspension system settings to the suspension controller 280. The suspension system (e.g., 111) of vehicle 121 can be adjusted to a critically damped, over-damped, or under-damped vehicle suspension system via the variable damper 281.

[0088] Therefore, the torque control of various powertrain components can be monitored by the vehicle system controller 12, wherein local torque control of the engine 110, transmission 125, motor 120 and brake 218 is provided by the engine controller 111B, the motor controller 252, the transmission controller 254 and the brake controller 141.

[0089] As an example, engine torque output can be controlled by adjusting a combination of ignition timing, fuel pulse width, fuel pulse timing, and / or intake manifold, by controlling the throttle opening (e.g., 62B), and / or the valve timing, valve lift, and boost pressure of a turbocharged or supercharged engine. In the case of a diesel engine, controller 12 can control engine torque output by controlling a combination of fuel pulse width, fuel pulse timing, and intake manifold. In all cases, engine control can be performed on a cylinder-by-cylinder basis to control engine torque output.

[0090] As is known in the prior art, motor controller 252 can control the torque output and electrical energy generated by motor 120 by adjusting the current flowing into and out of the excitation winding and / or armature winding of motor 120.

[0091] The transmission controller 254 may receive the transmission output shaft torque from the torque sensor 272. Alternatively, the sensor 272 may be a position sensor or a torque and position sensor. If the sensor 272 is a position sensor, the transmission controller 254 may count shaft position pulses at predetermined time intervals to determine the transmission output shaft speed. The transmission controller 254 may also distinguish the transmission output shaft speed to determine the transmission output shaft acceleration. The transmission controller 254, engine controller 111B, and vehicle system controller 12 may also receive additional transmission information from sensors 277, which may include, but are not limited to, pump output line pressure sensors, transmission hydraulic sensors (e.g., gear clutch fluid pressure sensors), motor temperature sensors, BISG temperature sensors, shift selector position sensors, synchronizer position sensors, and ambient temperature sensors. The transmission controller may also receive a requested transmission state (e.g., a requested gear or parking mode) from a shift selector 279, which may be a lever, switch, or other device.

[0092] The brake controller 141 receives wheel speed information from the wheel speed sensor 195 and receives braking requests from the vehicle system controller 12. The brake controller 141 can also receive braking requests directly or via CAN 299 from... Figure 1AThe brake pedal sensor (e.g., 157) shown receives brake pedal position information. The brake controller 141 can provide braking in response to wheel torque commands from the vehicle system controller 12. The brake controller 141 can also provide anti-lock braking and vehicle stability braking to improve vehicle braking and stability. Therefore, the brake controller 141 can provide wheel torque limits (e.g., not exceeding a threshold negative wheel torque) to the vehicle system controller 12, ensuring that negative motor torque does not exceed the wheel torque limits. For example, if the controller 12 issues a negative wheel torque limit of 50 N-m, the motor torque can be adjusted to provide less than 50 N-m (e.g., 49 N-m) of negative torque at the wheels, including for transmission shifting.

[0093] Positive torque can be transmitted to the wheels 131 in a direction that starts from the engine 110 and ends at the wheels 131. Therefore, depending on the direction of positive torque transmission in the drivetrain 200, the engine 110 is positioned upstream of the transmission 125. The transmission 125 is positioned upstream of the motor 120, and the BISG 142 can be positioned upstream of the engine 110, or downstream of the engine 110 and upstream of the transmission 125.

[0094] Figure 3 A detailed view of a dual-clutch transmission (DCT) 125 is shown. An engine crankshaft 40B is shown connected to a clutch housing 393. Alternatively, a shaft can be used to connect the crankshaft 40B to the clutch housing 393. The clutch housing 393 can rotate according to the rotation of the crankshaft 40B. The clutch housing 393 may include a first clutch 126 and a second clutch 127. Furthermore, each of the first clutch 126 and the second clutch 127 has an associated first clutch plate 390 and a second clutch plate 391, respectively. In some examples, the clutch may comprise a wet clutch immersed in oil (for cooling) or a dry clutch. Engine torque can be transmitted from the clutch housing 393 to either the first clutch 126 or the second clutch 127. The first transmission clutch 126 is connected to the engine 110 (e.g., Figure 1A Torque is transmitted between the engine 110 (as shown) and the first transmission input shaft 302. Therefore, the clutch housing 393 can be referred to as the input side of the first transmission clutch 126, and 126A can be referred to as the output side of the first transmission clutch 126. The second transmission clutch 127 transmits torque between the engine 110 (as shown) and the first transmission input shaft 302. Figure 1A Torque is transmitted between the second transmission input shaft 304 and the second transmission input shaft 307 (as shown). Therefore, the clutch housing 393 can be referred to as the input side of the second transmission clutch 127, and 127A can be referred to as the output side of the second transmission clutch 127.

[0095] As described above, the gearbox 128 may include multiple gears. Two transmission input shafts are present, including a first transmission input shaft 302 and a second transmission input shaft 304. The second transmission input shaft 304 is hollow, while the first transmission input shaft 302 is solid and coaxially located within the second transmission input shaft 304. As an example, the first transmission input shaft 302 may have multiple fixed gears. For example, the first transmission input shaft 302 may include a first fixed gear 306 for receiving a first gear 320, a third fixed gear 310 for receiving a third gear 324, a fifth fixed gear 314 for receiving a fifth gear 329, and a seventh fixed gear 318 for receiving a seventh gear 332. In other words, the first transmission input shaft 302 may be selectively connected to multiple odd-numbered gears. The second transmission input shaft 304 may include a second fixed gear 308 for receiving a second gear 322 or a reverse gear 328, and may also include a fourth fixed gear 316 for receiving a fourth gear 326 or a sixth gear 330. It should be understood that both the first transmission input shaft 302 and the second transmission input shaft 304 can be connected to each of the first clutch 126 and the second clutch 127 respectively via spines (not shown) on the outer side of each shaft. In a normal stationary state, each of the first clutch 126 and the second clutch 127 is held disengaged, for example by a spring (not shown), such that when each of the clutches is disengaged, no torque from the engine (e.g., 110) is transmitted to either the first transmission input shaft 302 or the second transmission input shaft 304. Engine torque can be transmitted to the first transmission input shaft 302 in response to engagement of the first clutch 126, and engine torque can be transmitted to the second transmission input shaft 304 in response to engagement of the second clutch 127. During normal operation, the transmission electronics ensure that only one clutch is engaged at any given time.

[0096] The gearbox 128 may also include a first countershaft 340 and a second countershaft 342. The gears on the first countershaft 340 and the second countershaft 342 are not fixed but are freely rotatable. In the exemplary DCT 125, the first countershaft 340 includes a first gear 320, a second gear 322, a sixth gear 330, and a seventh gear 332. The second countershaft 342 includes a third gear 324, a fourth gear 326, a fifth gear 329, and a reverse gear 328. Both the first countershaft 340 and the second countershaft 342 can transmit torque to gear 353 via a first output pinion 350 and a second output pinion 352, respectively. In this way, the two countershafts can transmit torque to an output shaft 362 via each of the first output pinion 350 and the second output pinion 352, wherein the output shaft can transmit torque to the rear wheel drive unit 136. Figure 1AAs shown), the rear-wheel drive unit 136 can drive the drive wheels (e.g., Figure 1A Each of the 131) can rotate at different speeds, for example, when performing steering maneuvers.

[0097] As described above, each of the first gear 320, second gear 322, third gear 324, fourth gear 326, fifth gear 329, sixth gear 330, seventh gear 332, and reverse gear 328 is not fixed to the countershaft (e.g., 340 and 342), but is free to rotate. Because of this, synchronizers can be used to match the rotational speed of each gear to the countershaft, and can also be used to lock the gears. In the exemplary DCT125, four synchronizers are shown, such as the first synchronizer 370, second synchronizer 374, third synchronizer 380, and fourth synchronizer 384. The first synchronizer 370 includes a corresponding first shift fork 372, the second synchronizer 374 includes a corresponding second shift fork 376, the third synchronizer 380 includes a corresponding third shift fork 378, and the fourth synchronizer 384 includes a corresponding fourth shift fork 382. Each of the shift forks allows each corresponding synchronizer to move to lock one or more gears, or to unlock one or more gears. For example, the first synchronizer 370 can be used to lock the first gear 320 or the seventh gear 332. The second synchronizer 374 can be used to lock the second gear 322 or the sixth gear 330. The third synchronizer 380 can be used to lock the third gear 324 or the fifth gear 329. The fourth synchronizer 384 can be used to lock the fourth gear 326 or the reverse gear 328. In each case, the movement of the synchronizers is accomplished by moving each of the corresponding synchronizers to the desired position using shift forks (e.g., 372, 376, 378, and 382).

[0098] The synchronizer movement via the shift fork can be performed via the transmission control module (TCM) 254 and the shift fork actuator 388, wherein the TCM 254 may contain the above-mentioned... Figure 2The TCM254 under discussion can operate the shift fork actuator electrically, hydraulically, or a combination of both. Hydraulic power can be provided via pump 312 and / or pump 367. The TCM254 can acquire input signals from various sensors, evaluate the inputs, and control the various actuators accordingly. The inputs used by the TCM254 may include, but are not limited to, transmission gear position (P / R / N / D / S / L, etc.), vehicle speed, engine speed and torque, throttle position, engine temperature, ambient temperature, steering angle, brake input, gearbox input shaft speed (for the first transmission input shaft 302 and the second transmission input shaft 304), and vehicle attitude (tilt). The TCM can control the actuators via open-loop control to achieve adaptive control. For example, adaptive control can enable the TCM254 to identify and adapt to the clutch engagement point, clutch friction coefficient, and synchronizer assembly position. The TCM254 can also adjust the first clutch actuator 389 and the second clutch actuator 387 to disengage and engage the first clutch 126 and the second clutch 127. The first clutch actuator 389 and the second clutch actuator 387 can be operated electrically, hydraulically, or a combination of electrically and hydraulically. Hydraulic power can be provided by pump 312 and / or pump 367.

[0099] Therefore, the TCM254 is shown as receiving input from various sensors 277. (As mentioned above...) Figure 2 The various sensors may include pump output line pressure sensors, transmission hydraulic sensors (e.g., gear clutch fluid pressure sensors), motor temperature sensors, shifter position sensors, synchronizer position sensors, and ambient temperature sensors. The various sensors 277 may also include wheel speed sensors (e.g., 195), engine speed sensors, engine torque sensors, throttle position sensors, engine temperature sensors, steering angle sensors, and inertial sensors (e.g., 199). (See above regarding...) Figure 1A The inertial sensor may include one or more of the following sensors: longitudinal sensor, lateral sensor, vertical sensor, yaw sensor, tilt sensor, and pitch sensor.

[0100] Sensor 277 may also include an input shaft speed (ISS) sensor, which may include a magnetoresistive sensor, and wherein each gearbox input shaft may include one ISS sensor (e.g., one ISS sensor for the first transmission input shaft 302 and one ISS sensor for the second transmission input shaft 304). Sensor 277 may also include an output shaft speed (OSS) sensor, which may include a magnetoresistive sensor and may be attached to the output shaft 362. Sensor 277 may also include a transmission gear (TR) sensor that can be used by the TCM to detect the position of shift forks (e.g., 372, 376, 378, 382).

[0101] DCT125 can be understood to function as described herein. For example, when the first clutch 126 is actuated and engaged, engine torque can be supplied to the first transmission input shaft 302. When the first clutch 126 is engaged, it should be understood that the second clutch 127 is disengaged, and vice versa. Based on which gear is locked when the first clutch 126 is engaged, power can be transmitted through the first transmission input shaft 302 to the first countershaft 340 or the second countershaft 342, and also through the first pinion 350 or the second pinion 352 to the output shaft 362. Alternatively, when the second clutch 127 is engaged, based on which gear is locked, power can be transmitted through the second transmission input shaft 304 to the first countershaft 340 or the second countershaft 342, and also through the first pinion 350 or the second pinion 352 to the output shaft 362. It should be understood that when torque is transmitted to a secondary shaft (e.g., the first output shaft 340), the other secondary shaft (e.g., the second output shaft 342) can continue to rotate even if only one shaft is directly driven by that input. More specifically, since the unengaged shaft (e.g., the second secondary shaft 342) is indirectly driven by the output shaft 362 and the corresponding pinion (e.g., the second pinion 352), the unengaged shaft (e.g., the second secondary shaft 342) can continue to rotate.

[0102] The DCT125 can preselect gears, allowing for rapid gear shifting with minimal torque loss during gear changes. As an example, when the first gear 320 is locked via the first synchronizer 370, and the first clutch 126 is engaged (and the second clutch 127 is disengaged), power can be transmitted from the engine to the first input shaft 302 and then to the first countershaft 340. While the first gear 320 is engaged, the second gear 322 can simultaneously be locked via the second synchronizer 374. Because the second gear 322 is locked, this allows the second input shaft 304 to rotate, with its rotational speed matching the vehicle speed under the second gear. Alternatively, if the preselected gear is located on another countershaft (e.g., the second countershaft 342), the countershaft will also rotate due to its being driven by the output shaft 362 and the pinion 352.

[0103] When shifting is initiated via TCM254, only the clutch needs to be actuated to disengage the first clutch 126 and engage the second clutch 127. Furthermore, outside the TCM control range, the engine speed can be reduced to match the upshift. With the second clutch 127 engaged, power can be transmitted from the engine to the second input shaft 304, to the first countershaft 340, and also to the output shaft 362 via pinion 350. After the shift is complete, TCM254 can appropriately pre-select the next gear. For example, TCM254 can pre-select a higher or lower gear based on inputs received from various sensors 277. In this way, shifting can be achieved quickly with minimal loss of engine torque supplied to the output shaft 362.

[0104] In some examples, the dual-clutch transmission 125 may include a parking gear 360. A parking pawl 363 may be oriented toward the parking gear 360. When the shift control lever is set to park, the parking pawl 363 may engage the parking gear 360. Engagement of the parking pawl 363 with the parking gear 360 may be achieved by a parking pawl spring 364, or by, for example, a cable (not shown), a hydraulic piston (not shown), or a motor (not shown). When the parking pawl 363 is engaged with the parking gear 360, the vehicle's drive wheels (e.g., front wheels 130, rear wheels 131) may be locked. Alternatively, in response to the shift control lever moving from park to another selection (e.g., drive), the parking pawl 363 may move such that it can disengage from the parking gear 360.

[0105] In some examples, the electric transmission pump 312 may supply hydraulic fluid from the transmission oil reservoir 311 to compress the spring 364 in order to release the parking pawl 363 from the parking gear 360. For example, the electric transmission pump 312 may be powered by an onboard energy storage device (e.g., 132). In some examples, a mechanical pump 367 may additionally or alternatively supply hydraulic fluid from the transmission oil reservoir 311 to compress the spring 364 in order to release the parking pawl 363 from the parking gear 360. Although not explicitly shown, the mechanical pump may be driven by an engine (e.g., 110) and may be mechanically connected to the clutch housing 393. In some examples, the parking pawl valve 361 may adjust the flow rate of hydraulic fluid reaching the spring 364.

[0106] therefore, Figure 1A-3 The system provides a system comprising: an engine; an integrated starter / generator connected to the engine; a transmission including a first input clutch, a second input clutch, a first input shaft and a second input shaft, a first countershaft selectively connected to the first input shaft, a second countershaft selectively connected to the second input shaft, a plurality of gears, and an output shaft connected to the first and second countershafts; a rear-wheel drive unit including a rear axle and an electric motor connected to the dual-clutch transmission via a drive shaft; and a controller including executable instructions stored in a non-transitory memory, the executable instructions providing wheel torque in response to a desired vehicle acceleration, the desired vehicle acceleration being responsive to an accelerator pedal position, a current vehicle speed, and a currently engaged transmission gear. The system also includes additional instructions for providing wheel torque via the electric motor included in the rear-wheel drive unit. The system further includes additional instructions for adjusting to provide wheel torque via the engine. The system includes a component wherein the desired vehicle acceleration is a portion of the vehicle acceleration rate under the first gear and a portion of the vehicle acceleration under the second gear. The system also includes additional instructions for referencing a lookup table via the accelerator pedal position, the current vehicle speed, and the currently engaged transmission gear. The system also includes additional instructions to convert the desired vehicle acceleration into wheel torque.

[0107] Now for reference Figure 4 The flowchart shows a method for controlling a vehicle's drivetrain. Figure 4 The method can be merged into Figure 1A-3 In the system, and can be with Figure 1A-3 System collaboration. Furthermore... Figure 4 At least some parts of the method can be merged into executable instructions stored in non-transitory memory, while other parts of the method can be executed by a controller changing the operating state of the device and actuator in the physical world.

[0108] At point 402, method 400 determines the vehicle's operating status. The vehicle's operating status can be determined via... Figure 1A-3 The various sensors described herein, or inferences based on sensor outputs, determine the vehicle's operating conditions. These conditions may include, but are not limited to, vehicle speed, accelerator pedal position, transmission ratio, currently engaged transmission gear, desired transmission gear, vehicle operating mode, road conditions, and vehicle load. The transmission ratio can be determined by dividing the transmission input speed by the transmission output speed. Road conditions may include road gradient, which can be determined via a map stored in the controller's memory or a global positioning system. Methods 400 through 404 are then performed.

[0109] At 404, method 400 determines the requested vehicle acceleration. In one example, a map or value table is indexed or referenced by the accelerator pedal position and vehicle speed. The map or table outputs an empirically determined vehicle acceleration value. For example, if the accelerator pedal is applied at 10% of full scale and the vehicle speed is 20 km / h (kPH), the table or map may output a vehicle acceleration of 2.5 km / h / s (kPH / s). Method 400 proceeds to 406.

[0110] At position 406, method 400 determines the wheel torque based on the desired vehicle acceleration rate. In one example, method 400 determines the wheel torque using the following equation:

[0111] Tq whl =F·R

[0112]

[0113]

[0114] Where Tq whl F is the wheel torque, R is the force applied to the wheel, and J is the tire radius. eqv It is the equivalent inertia of the rotating components of the transmission system, m veh It's about the quality of the vehicle, Acc des It is the expected vehicle acceleration from step 404, where g is the gravitational constant, θ is the road angle, and c is the gravitational constant. rr Here, ρ is the rolling resistance coefficient, ρ is the air density, Vehspd is the vehicle speed, and c is the rolling resistance coefficient. d Rt is the vehicle drag coefficient, A is the vehicle's frontal area, and Rt is the vehicle's drag coefficient. trn Rt is the transmission ratio under the currently engaged transmission gear. fd It is the final drive ratio (e.g., axle ratio), J is1 It is the inertia of the first transmission input shaft, R is1 J is the transmission ratio of the engagement or pre-selected gear connected to the first input shaft. is2It is the inertia of the second transmission input shaft, R is2 It is the transmission ratio of the engagement or pre-selected gear connected to the second input shaft, and J wh1 It includes the effective wheel inertia, output shaft inertia, and RDU motor inertia. J eqv The first term can be ignored or set to zero if the vehicle is not operating in hybrid mode where the engine is connected to the transmission. In some examples, J eng This can be focused on the ISG inertia. Method 400 proceeds to 408.

[0115] At 408, method 400 provides the desired wheel torque. The desired wheel torque can be provided via a rear-wheel drive unit (RDU) motor, engine, ISG, or BISG. The desired wheel torque can be provided by a combination of an RDU motor and engine, an RDU motor and ISG, an RDU motor and BISG, an engine and ISG, or an engine and BISG. In one example, a portion of the desired wheel torque is allocated to each torque source (e.g., engine, ISG, BISG, RDU motor). The portion allocated to each torque source can be a function of battery state of charge, the desired wheel torque amount, battery temperature, RDU temperature, and other parameters. The torque sources then provide the desired wheel torque to compensate for the gear ratio and clutch torque capacity. For example, if the desired wheel torque is 500 N-m and the engine and RDU motor are each required to provide 250 N-m of wheel torque, then the RDU motor provides 250 / R... fd_rdu The torque in Nm, where R fd_rdu This is the final drive ratio of the RDU. The engine provides 250 / (R fd ·R trn Torque in Nm. Method 400 continues until exit.

[0116] In this way, the accelerator pedal position can be converted into a desired vehicle acceleration, and the desired vehicle acceleration can be converted into a desired wheel torque that can be provided via the drivetrain torque source. This method can be applied to drivetrain configurations different from those disclosed herein. Thus, the currently disclosed drivetrain configurations do not limit the scope of this disclosure.

[0117] Go to Figure 5 This illustrates the predictive powertrain operating sequence of a hybrid vehicle. It can be achieved through... Figure 1A-3 The system and Figure 4 To provide Figure 5 The runtime sequence. Figure 5 The curves shown occur simultaneously and are aligned in time. The vertical line T0-T1 represents the time of interest during the transmission system's operation sequence. Figure 5The timing diagram illustrates how to maintain the desired vehicle acceleration in response to changes in the operating mode of a hybrid vehicle.

[0118] from Figure 5 The first graph at the top is the desired vehicle acceleration versus time. The vertical axis represents the desired vehicle acceleration, and the desired vehicle acceleration increases in the direction of the arrow on the vertical axis. The horizontal axis represents time, and time increases from the left side of the graph to the right side.

[0119] from Figure 5 The second graph starting from the top is a graph of the requested wheel torque versus time. The vertical axis represents the requested wheel torque, and the requested wheel torque increases in the direction of the arrow on the vertical axis. The horizontal axis represents time, and time increases from the left side of the graph to the right side.

[0120] from Figure 5 The third graph, starting from the top, is a graph of the powertrain's operating mode versus time. The vertical axis represents the powertrain's operating mode, and when the trajectory is at the Electric Vehicle (EV) level, the powertrain is in EV mode (e.g., operating without an engine). When the trajectory is at the HEV level, the powertrain is in Hybrid Vehicle mode (e.g., operating with an engine). The horizontal axis represents time, and time increases from the left side of the graph to the right side.

[0121] from Figure 5 The fourth graph starting from the top is a graph of the accelerator pedal position relative to time. The vertical axis represents the accelerator pedal position, and the accelerator pedal position increases along the direction of the arrow on the vertical axis. The horizontal axis represents time, and time increases from the left side of the graph to the right side.

[0122] At time T0, the accelerator pedal position is at a moderate level. The expected vehicle acceleration is also at a moderate level, and the powertrain operates in pure electric vehicle mode without the engine running. The engine is not connected to the transmission shaft when the engine is not running. Therefore, the engine's inertia is not part of the rotational drivetrain that propels the vehicle.

[0123] At time T1, the vehicle's operating mode changes from pure electric vehicle mode to hybrid vehicle mode with the engine running. This mode change can be facilitated by a low battery state of charge or other conditions (not shown). However, since the accelerator position has not changed since time T0, the mode change does not respond to a change in accelerator pedal position. The desired vehicle acceleration remains constant, and wheel torque increases to compensate for the engine inertia that increases in the drivetrain when the vehicle enters hybrid mode.

[0124] In this way, the desired wheel torque can be adjusted to compensate for changes in vehicle mode caused by increased or decreased inertia from the vehicle's drivetrain. Thus, wheel torque can be altered to maintain a desired level of vehicle acceleration.

[0125] Now for reference Figure 6 The flowchart shows a method for controlling a vehicle's drivetrain. Figure 6 The method can be merged into Figure 1A-3 In the system, and can be with Figure 1A-3 System collaboration. Furthermore... Figure 6 At least some parts of the method can be merged into executable instructions stored in non-transitory memory, while other parts of the method can be executed by changing the operating state of the devices and actuators in the physical world via a controller. The desired vehicle acceleration can be achieved by the vehicle operating in a hybrid mode where the engine burns air and fuel via... Figure 6 The method is used to determine this.

[0126] At point 602, method 600 determines the vehicle's operating status. The vehicle's operating status can be determined via... Figure 1A-3 The various sensors described herein, or inferences based on sensor outputs, determine the vehicle operating conditions. Vehicle operating conditions may include, but are not limited to, vehicle speed, accelerator pedal position, transmission ratio, currently engaged transmission gear, desired transmission gear, vehicle operating mode, road conditions, and vehicle load. The transmission ratio can be determined by dividing the transmission input speed by the transmission output speed. Road conditions may include road gradient, which can be determined using a map stored in the controller memory or a global positioning system. The desired gear is the gear the transmission may attempt to engage in response to the vehicle operating conditions. Methods 600 through 604 are performed.

[0127] At 604, method 600 determines two requested vehicle accelerations. In one example, the first vehicle acceleration (e.g., Acc_Gear) is determined via a first map or value table using the accelerator pedal position, vehicle speed, and the index or reference of the currently engaged transmission gear. The map or table outputs an empirically determined vehicle acceleration value. For example, if the accelerator pedal is applied at 10% of full scale, the vehicle speed is 20 kPH, and the transmission is engaged in the second gear, the table or map may output a vehicle acceleration rate of 2.5 kPH / s. The second vehicle acceleration (e.g., Acc_TrgGear) is determined via a second map or value table using the accelerator pedal position, vehicle speed, and the desired transmission gear index or reference. The map or table outputs an empirically determined vehicle acceleration value. For example, if the accelerator pedal is applied at 10% of full scale, the vehicle speed is 20 kPH, and the desired transmission gear is the third gear, the table or map may output a vehicle acceleration rate of 1.5 kPH / s. By including the gear ratio when determining the vehicle acceleration, the estimated value of the vehicle acceleration can be improved. Method 600 is followed up to 606.

[0128] At point 606, method 600 determines the vehicle acceleration blending ratio parameter. In one example, the vehicle acceleration blending ratio is determined using the following formula:

[0129]

[0130] Where Rt_Blend is the vehicle acceleration blending ratio parameter, Rt_TrnsSpd is the transmission gear ratio, Rt_CurGear is the gear ratio of the currently engaged transmission gear, and Rt_TrgGear is the desired transmission gear ratio. Methods 600 to 608 are then performed.

[0131] At point 608, method 600 determines the desired vehicle acceleration. In one example, method 600 determines the desired vehicle acceleration according to the following equation:

[0132] Acc_dsd = (1 - Rt_Blend)·Acc_Gear + Rt_Blend·Acc_TrgGear, where Acc_dsd is the desired vehicle acceleration, Rt_Blend is the blending ratio parameter, Acc_Gear is the first vehicle acceleration (e.g., vehicle acceleration under the first gear) as determined at 604, and Acc_TrgGear is the second vehicle acceleration (e.g., vehicle acceleration under the second gear) as determined at 604. By blending the two accelerations into a single acceleration, drivetrain torque disturbances can be reduced. Methods 600 proceed to 610.

[0133] At 610, method 600 determines and provides the desired wheel torque. The desired wheel torque can be determined as described at 406 of method 400.

[0134] The desired wheel torque can be provided by a rear-wheel drive unit (RDU) motor, engine, ISG, or BISG. The desired wheel torque can be provided by a combination of an RDU motor and engine, an RDU motor and ISG, an RDU motor and BISG, an engine and ISG, or an engine and BISG. In one example, a portion of the desired wheel torque is allocated to each torque source (e.g., engine, ISG, BISG, RDU motor). The portion allocated to each torque source can be a function of battery state of charge, the desired wheel torque amount, battery temperature, RDU temperature, and other parameters. The torque sources then provide the desired wheel torque to compensate for gear ratios and clutch torque capacity.

[0135] In this way, the desired vehicle acceleration can be determined using the accelerator pedal position, vehicle speed, and transmission gear ratio, and the desired vehicle acceleration can be converted into desired wheel torque that can be provided via the drivetrain torque source. This method can be applied to drivetrain configurations different from those disclosed herein. Accordingly, the currently disclosed drivetrain configurations do not limit the scope of this disclosure.

[0136] Now for reference Figure 7 This illustrates the predictive powertrain operating sequence of a hybrid vehicle. It can be achieved through... Figure 1A-3 The system and Figure 6 To provide Figure 7 The runtime sequence. Figure 7 The curves shown occur simultaneously and are aligned in time. The vertical line T0-T1 represents the time of interest during the transmission system's operation sequence. Figure 7 The timing diagram illustrates how the desired vehicle acceleration can develop during transmission gear upshifts when the gear is engaged (e.g., when the accelerator pedal is applied).

[0137] from Figure 7 The first graph, starting at the top, is a graph of the transmission gears relative to time. The vertical axis represents the transmission gears, and the transmission gear numbers are indicated along the vertical axis. The solid line 702 represents the currently engaged transmission gear, and the dashed line 704 represents the expected transmission gear. The expected transmission gear and the currently engaged transmission gear are the same gear when only the solid line trace 702 is visible. The expected transmission gear is the gear that the controller plans to engage at a later time. The horizontal axis represents time, and time increases from the left side of the graph to the right side.

[0138] from Figure 7The second graph starting from the top is a graph of the transmission gear ratio versus time. The vertical axis represents the transmission gear ratio, and the gear ratio increases in the direction of the arrow on the vertical axis. The horizontal axis represents time, and time increases from the left side of the graph to the right side. The solid line 708 represents the gear ratio of the currently engaged gear. The dashed line 706 represents the desired gear ratio. The desired transmission gear ratio and the currently engaged transmission gear ratio are the same when only the solid line trace 708 is visible. The desired transmission gear ratio is the gear ratio that the controller plans to engage at a later time.

[0139] from Figure 7 The third graph starting from the top is a graph of the transmission ratio versus time. The vertical axis represents the transmission ratio, and the transmission ratio increases in the direction of the arrow on the vertical axis. The horizontal axis represents time, and time increases from the left side of the graph to the right side.

[0140] from Figure 7 The fourth graph starting from the top is a graph of the vehicle acceleration engagement ratio versus time. The vertical axis represents the vehicle acceleration engagement ratio, and the vehicle acceleration engagement ratio value is set along the vertical axis. The horizontal axis represents time, and time increases from the left side of the graph to the right side.

[0141] At time T10, the second gear of the transmission is engaged, and the desired transmission gear is the second gear. The desired transmission gear ratio and the current transmission gear ratio are the same higher gear ratio, i.e., the gear ratio of the second gear. The transmission gear ratio is a higher value, and the vehicle acceleration engagement ratio is zero.

[0142] At time T11, the desired transmission gear changes from the second gear to the third gear, and the desired transmission gear ratio changes from a higher value to a lower value to indicate a difference in the gear ratio between the second and third gears. The desired gear ratio can change in response to an increase in vehicle speed and approaching the speed at which the second-to-third gear shift will occur. Since the gear shift has not yet begun, the transmission gear ratio remains at its previous value and the vehicle acceleration engagement value remains zero.

[0143] At time T12, a gear shift from the second to the third gear is underway, and the transmission ratio begins to decrease. The vehicle acceleration engagement ratio also begins to increase. The transmission remains on the second gear, and the transmission gear ratio remains constant. The desired transmission gear is the third gear, and the desired transmission gear ratio is the gear ratio of the third gear.

[0144] Between time T12 and time T13, the vehicle acceleration engagement ratio increases from a value of 0 to a value of 1. By changing the value of the acceleration engagement ratio, a larger portion of the vehicle acceleration requested at the start of a shift responds to the vehicle acceleration based on the engagement of the second gear. However, at the end of a shift, the requested vehicle acceleration responds only to the vehicle acceleration under the third gear.

[0145] At time T13, the shift from the second gear to the third gear is completed. The desired transmission gear and the currently engaged transmission gear are both the third gear. The desired transmission gear ratio and the current transmission gear ratio are the same value. The transmission gear ratio is the lower value corresponding to the third gear, and the vehicle acceleration engagement ratio is 1.

[0146] In this way, the desired vehicle acceleration can be adjusted in response to the engaged transmission gears. During gear shifts, the desired vehicle acceleration is adjusted in response to gear disengagement and engagement.

[0147] therefore, Figure 4 and 6 A method provides a drivetrain operation method comprising: providing wheel torque in response to a desired vehicle acceleration, the desired vehicle acceleration being responsive to accelerator pedal position and current vehicle speed. The method includes providing wheel torque via an engine and an electric motor. The method further includes outputting the desired vehicle acceleration from a lookup table referenced by the accelerator pedal position and current vehicle speed. The method further includes converting the desired vehicle acceleration into wheel torque. The method includes adjusting an estimated value of the wheel torque in response to the drivetrain moment of inertia, wherein the drivetrain moment of inertia varies with the vehicle operating mode. The method includes adjusting the estimated value of the wheel torque in response to the vehicle's frontal area and vehicle mass. The method includes adjusting the estimated value of the wheel torque in response to the wheel's rolling resistance coefficient.

[0148] Figure 4 and 6The method also provides a drivetrain operation method comprising: providing wheel torque in response to a desired vehicle acceleration, the desired vehicle acceleration being responsive to accelerator pedal position, current vehicle speed, and currently engaged transmission gear. The method includes wherein the desired vehicle acceleration is a portion of the vehicle acceleration rate under a first gear and a portion of the vehicle acceleration under a second gear. The method includes wherein the portion of the vehicle acceleration rate under the first gear and the portion of the vehicle acceleration under the second gear are responsive to a gear ratio. In some examples, the method further includes wherein the gear ratio is based on a transmission gear ratio. The method includes wherein the desired vehicle acceleration is also responsive to a transmission gear ratio. The method further includes referencing a lookup table via the accelerator pedal position, current vehicle speed, and currently engaged transmission gear. The method includes wherein the lookup table outputs the desired vehicle acceleration under the transmission gear.

[0149] It should be noted that the exemplary control and estimation procedures included herein can be used with various engine and / or vehicle system configurations. The control methods and procedures disclosed herein can be stored as executable instructions in non-transitory memory and can be executed by a control system including a controller in conjunction with various sensors, actuators, and other engine hardware. Furthermore, parts of the method can be physical actions taken in the real world to change the state of a device. The specific procedures described herein can represent one or more of any number of processing strategies, such as event-driven, interrupt-driven, multitasking, multithreading, etc. Therefore, the various actions, operations, and / or functions shown can be executed in the shown timing sequence, in parallel, or in some cases, omitted. Similarly, the timing of the process is not necessary to achieve the features and advantages of the exemplary embodiments described herein, but is set for ease of illustration and description. One or more of the shown actions, operations, and / or functions can be repeatedly executed according to the specific strategy used. Furthermore, the described actions, operations, and / or functions can be graphically represented as code programmed into a non-transitory memory of a computer-readable storage medium in an engine control system, wherein the described actions are performed by executing instructions in a system including various engine hardware components combined with an electronic controller. If necessary, one or more of the method steps described herein may be omitted.

[0150] It should be understood that the configurations and procedures disclosed herein are exemplary in nature, and because many variations are possible, these specific embodiments are not considered limiting. For example, the above-described techniques can be applied to V-6, I-4, I-6, V-12, opposed 4, and other engine types. The subject matter of this disclosure includes all novel and non-obvious combinations and sub-combinations of the various systems and configurations disclosed herein, as well as other features, functions, and / or characteristics.

[0151] The following claims specifically point to certain combinations and sub-combinations that are considered novel and non-obvious. These claims may refer to a “one” element or a “first” element or its equivalent. Such claims should be understood to include one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and sub-combinations of the disclosed features, functions, elements, and / or characteristics may be claimed by amending these claims or by filing new claims in this application or related applications. Such claims, whether broader, narrower, equal to, or different in scope from the original claims, are also considered to be included within the subject matter of this disclosure.

Claims

1. A method for operating a transmission system, comprising: Wheel torque is provided in response to desired vehicle acceleration, which is responsive to accelerator pedal position, transmission gear ratio, and current vehicle speed, wherein the motor is located downstream of the transmission. The desired vehicle acceleration is obtained by harmonic coupling of a first vehicle acceleration and a second vehicle acceleration according to a coupling ratio parameter determined based on changes in the transmission gear ratio. The first vehicle acceleration is determined by a first map or value table via the accelerator pedal position, vehicle speed, and the currently engaged transmission gear index or reference; and the second vehicle acceleration is determined by a second map or value table via the accelerator pedal position, vehicle speed, and the desired transmission gear index or reference.

2. The method of claim 1, wherein the wheel torque is provided via an engine and an electric motor.

3. The method of claim 2, further comprising outputting the desired vehicle acceleration from a lookup table referenced via the accelerator pedal position and the current vehicle speed.

4. The method of claim 3, further comprising converting the desired vehicle acceleration into the wheel torque.

5. The method of claim 4, wherein converting the desired vehicle acceleration into the wheel torque includes adjusting an estimated value of the wheel torque in response to the drivetrain moment of inertia, and wherein the drivetrain moment of inertia varies with the vehicle operating mode.

6. The method of claim 5, wherein converting the desired vehicle acceleration into the wheel torque includes adjusting an estimate of the wheel torque in response to the vehicle's frontal area and the vehicle's mass.

7. The method of claim 6, wherein converting the desired vehicle acceleration into the wheel torque includes adjusting an estimate of the wheel torque in response to the rolling resistance coefficient of the wheel.

8. The method of claim 1, further comprising providing the wheel torque in response to the currently engaged transmission gear.

9. The method of claim 8, wherein the desired vehicle acceleration is a portion of the vehicle acceleration rate under the first gear and a portion of the vehicle acceleration under the second gear.

10. A system comprising: engine; An integrated starter / generator connected to the engine; A transmission, the transmission including a first input clutch, a second input clutch, a first input shaft and a second input shaft, a first countershaft selectively connected to the first input shaft, a second countershaft selectively connected to the second input shaft, a plurality of gears, and an output shaft connected to the first countershaft and the second countershaft; A rear-wheel drive system, comprising a rear axle and a motor connected to the transmission via a drive shaft; and A controller includes executable instructions stored in a non-transitory memory for providing wheel torque in response to a desired vehicle acceleration, the desired vehicle acceleration being responsive to accelerator pedal position, current vehicle speed, and currently engaged transmission gear. The controller also includes obtaining the desired vehicle acceleration by adjusting a first vehicle acceleration and a second vehicle acceleration according to a engagement ratio parameter determined based on the change in the transmission gear ratio when the transmission gear ratio changes. The first vehicle acceleration is determined by a first map or value table via the accelerator pedal position, vehicle speed, and the currently engaged transmission gear index or reference; and the second vehicle acceleration is determined by a second map or value table via the accelerator pedal position, vehicle speed, and the desired transmission gear index or reference.

11. The system of claim 10, further comprising additional instructions for providing the wheel torque via the motor included in the rear wheel drive unit.

12. The system of claim 10, further comprising additional instructions for adjusting to provide the wheel torque via the engine.

13. The system of claim 10, wherein the desired vehicle acceleration is a portion of the vehicle acceleration rate under the first gear and a portion of the vehicle acceleration under the second gear.

14. The system of claim 10, further comprising additional instructions for referencing a lookup table via the accelerator pedal position, the current vehicle speed, and the currently engaged transmission gear.

15. The system of claim 14, further comprising additional instructions for converting the desired vehicle acceleration into the wheel torque.

16. A method for operating a transmission system, comprising: Wheel torque is provided in response to desired vehicle acceleration, which is responsive to accelerator pedal position, current vehicle speed, and currently engaged transmission gear; and The motor is located downstream of the transmission. When the gear ratio of the transmission gears changes, the desired vehicle acceleration is obtained by adjusting the first vehicle acceleration and the second vehicle acceleration according to the adjustment ratio parameter, which is determined according to the change of the gear ratio of the transmission gears. in, The first vehicle acceleration is determined by a first map or value table via the accelerator pedal position, vehicle speed, and the currently engaged transmission gear index or reference; and the second vehicle acceleration is determined by a second map or value table via the accelerator pedal position, vehicle speed, and the desired transmission gear index or reference.

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