Regenerative hybrid vehicle braking system and method

Abstract

This invention provides a method and system for operating a hybrid vehicle during conditions requiring vehicle braking. In one example, regenerative braking is distributed to the axle in response to the activation of the anti-lock braking system (ABS) and the wheel torque of the corresponding axle. Additionally, frictional braking torque is distributed to the axle in response to the activation of the ABS.

Description

Technical Field

[0001] This invention generally relates to methods and systems for controlling regenerative braking in hybrid vehicles. These methods and systems are particularly useful for four-wheel drive hybrid vehicles.

[0002] Background Art / Summary of the Invention

[0003] The kinetic energy of a hybrid vehicle can be converted into electrical energy via an electric motor in the vehicle's drivetrain. Specifically, wheel torque can be converted into electrical energy via the motor, a process known as regenerative braking. This electrical energy can be stored in an energy storage device until it is subsequently used to propel the vehicle. The electric motor can have significant inertia if it provides a large amount of torque to propel the vehicle. This significant inertia can be related to the number of windings in the motor and the mass of the motor's armature. A motor with significant inertia can be used to provide the desired rate of vehicle acceleration. However, the significant inertia and / or magnetic field strength of the motor can make it more difficult to mitigate the possibility of wheel lock-up during wheel braking while the motor is providing regenerative braking. It is desirable to provide regenerative braking during vehicle braking while simultaneously providing anti-lock wheel control, allowing the vehicle to decelerate at a desired rate and enabling the capture of at least a portion of the vehicle's kinetic energy.

[0004] The inventors have recognized the aforementioned problems herein and have developed a vehicle operation method comprising: adjusting the regenerative torque of the main shaft to the lower of the low-pass filtered main shaft adjustment torque of the right wheel and the low-pass filtered main shaft adjustment torque of the left wheel in response to activation of the anti-lock braking system.

[0005] By adjusting the main shaft's regulating torque in response to the activation of the anti-lock braking system (ABS) and in response to the lower of the low-pass filtered main shaft regulating torques of the right and left wheels, it is possible to provide regenerative vehicle braking while simultaneously regulating wheel speed, even if the drivetrain motors have significant inertia. In one example, the wheel regulating torque can be decomposed into regenerative braking torque and friction braking torque. The regenerative braking torque of the wheels may include a lower braking regulating torque frequency, and the friction braking torque of the wheels may include a higher regulating torque frequency, so that the motor torque does not need to respond to the higher wheel regulating torque frequency. On the other hand, the friction brake can respond to the higher wheel regulating torque frequency, thereby reducing the likelihood of wheel lock-up during regenerative braking. Additionally, the regenerative braking torque and friction braking torque of the secondary shaft can respond to other regulating torque frequencies to compensate for the inertia of other motors providing regenerative braking to the secondary shaft and the vehicle weight distribution.

[0006] This invention offers several advantages. For example, the method can improve the storage of a vehicle's kinetic energy into electrical energy. Additionally, the method can reduce the likelihood of wheel lock-up, even if the vehicle includes motors with significant inertia and / or magnetic fields. Furthermore, the method compensates for wheel torque control during conditions where regenerative braking may be limited due to abnormal vehicle operating conditions.

[0007] It should be understood that the above summary is provided to introduce a series of concepts in a simplified form, and these concepts are further described in the detailed embodiments. The above summary is not intended to identify 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 addressing any of the shortcomings mentioned above or any implementation thereof in any part of this disclosure. Attached Figure Description

[0008] Figure 1A This is a schematic diagram of the powertrain of a hybrid vehicle.

[0009] Figure 1B This is a sketch of the engine in the powertrain of a hybrid vehicle.

[0010] Figure 1C A schematic diagram of an alternative hybrid vehicle powertrain.

[0011] Figure 2 This is a schematic diagram of a hybrid vehicle powertrain that includes controllers for various powertrain components.

[0012] Figure 3 This is a schematic diagram of a dual-clutch transmission located in the powertrain of a hybrid vehicle.

[0013] Figure 4 A flowchart illustrating a method for controlling the braking of a hybrid vehicle is shown.

[0014] Figure 5 Showing according to Figure 4 The predictive vehicle operation sequence of the method. Detailed Implementation

[0015] The following description relates to systems and methods for operating the powertrain of a hybrid vehicle. Figures 1A to 3 An example hybrid vehicle system is shown, which includes a drivetrain with an internal combustion engine, an integrated starter / generator, a dual-clutch transmission, and an electric motor, the electric motor being operable in regenerative mode to store the vehicle's power as electrical energy. Figure 4 A method for controlling braking in a hybrid vehicle is shown, and the method includes compensating for wheel slippage. Figure 5 Showing according to Figure 4 The method is an example of vehicle operation sequence.

[0016] Figure 1A This describes an example vehicle propulsion system 100 for vehicle 121. 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 an energy source 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. Thus, a vehicle having propulsion system 100 can be referred to as a hybrid electric vehicle (HEV). Figure 1A The description uses solid lines to represent mechanical connections between various components and dashed lines to represent electrical connections between various components.

[0017] The vehicle propulsion system 100 has a front axle (not shown) and a rear axle 122. In some instances, 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 130a (left) and 130b (right) and rear wheels 131a (left) and 131b (right). In this example, the front wheels 130a (left) and 130b (right) are not driven, and the rear wheels 131a (left) and 131b (right) are driven electrically or via an engine 110. The rear axle 122 is coupled to a motor 120 and connected to a transmission 125 via a driveshaft 129. The rear axle 122 can be driven electrically and exclusively via the motor 120 (e.g., in an electric drive or propulsion mode where the engine is not burning air and fuel or rotating), in a hybrid mode via the motor 120 and the engine 110 (e.g., in a parallel mode), or exclusively via the engine 110 (e.g., in an engine-only propulsion mode) in a mode where only the engine is burning fuel. The rear drive unit 136 can transmit power from the engine 110 or the motor 120 to the axle 122, causing rotation of the drive wheels 131a (left) and 131b (right). The rear drive unit 136 may include a gear set, i.e., a differential 193, and an electronically controlled differential clutch 191 that adjusts the torque transmission to and from the axle 122a and the axle 122b. In some instances, the electronically controlled differential clutch 191 may transmit the clutch torque capacity (e.g., the amount of torque the clutch can transmit, and said amount may increase in response to an increased force applied to close the clutch) via a Controller Area Network (CAN) bus 299. When the electronically controlled differential clutch is open, the torque transmission to shafts 122a and 122b may be the same. When the electronically controlled differential clutch 191 is partially closed (e.g., slipping, such that the speed input to the clutch is different from the speed output of the clutch) or closed, the torque transmission to shaft 122a may be different from the torque transmitted to shaft 122b. The rear drive unit 136 may also include one or more clutches (not shown) for disengaging the transmission 125 and the motor 120 from wheels 131a (left) and 131b (right). The rear drive unit 136 may be directly coupled to the motor 120 and shaft 122. In some instances, a motor positioned directly downstream of the transmission 125 in the direction of the positive torque flow from the engine 110 can replace the rear drive unit 136.

[0018] Transmission 125 Figure 1AThe description indicates that the transmission 125 is connected between the engine 110 and the motor 120 assigned 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 driveshaft 129 to supply torque to the wheels 131a (left) and 131b (right). The following will discuss... Figure 2 In more detail, the transmission 125 can shift gears by selectively opening and closing the first clutch 126 and the second clutch 127.

[0019] The motor 120 can receive electrical power from the on-board energy storage device 132. Furthermore, the motor 120 can function as a generator to convert engine output or the vehicle's kinetic energy into electrical energy, which can be stored in the energy storage device 132 for later use by the motor 120 or the integrated starter / generator 142. A 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. The energy storage device 132 can be a battery, capacitor, inductor, or other energy storage device.

[0020] In some instances, the energy storage device 132 may be configured to store electrical energy that can be supplied to other electrical loads residing on the vehicle (other than the motor), including cabin heating and air conditioning, engine starting, headlights, cabin audio and video systems, etc.

[0021] 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, transmission 125, etc. The control system 14 can receive sensory feedback information from one or more of the following: engine 110, electric motor 120, energy storage device 132, integrated starter / generator 142, transmission 125, etc. Furthermore, the control system 14 can send control signals to one or more of the following in response to this sensory feedback: engine 110, electric motor 120, energy storage device 132, transmission 125, etc. The control system 14 can receive instructions from the human driver 102 or the autonomous controller regarding the output of the vehicle propulsion system. For example, the control system 14 can receive sensory feedback from a pedal position sensor 194, which communicates with pedal 192. Pedal 192 can schematically refer to the accelerator pedal. Similarly, the control system 14 can receive instructions from the human driver 102 or the autonomous controller regarding vehicle braking. For example, the control system 14 may receive sensory feedback from a pedal position sensor 157, which communicates with the brake pedal 156.

[0022] Energy storage device 132 can periodically receive electrical energy from a power source 180 (e.g., a static electrical grid) residing outside the vehicle (e.g., not part of the vehicle), as indicated by arrow 184. As a non-limiting example, vehicle propulsion system 100 can be configured as a plug-in hybrid electric vehicle (HEV), whereby electrical energy can be supplied from power source 180 to energy storage device 132 via power transmission cable 182. During recharging operations of energy storage device 132 from power source 180, power transmission cable 182 can electrically couple energy storage device 132 and power source 180. In some instances, power source 180 can be connected at air intake 150. Furthermore, in some instances, charging status indicator 151 can display the charging status of energy storage device 132.

[0023] In some instances, 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 function as an electrical power converter.

[0024] When the vehicle propulsion system is operated to propel the vehicle, the power transmission cable 182 may be disconnected between the power source 180 and the energy storage device 132. The control system 14 may identify and / or control the amount of electrical energy stored in the energy storage device, which may be referred to as the state of charge (SOC).

[0025] In other instances, the power transmission cable 182 may be omitted, where electrical energy can be received wirelessly from the power source 180 at the energy storage device 132. For example, the energy storage device 132 may receive electrical energy from the power source 180 via one or more of electromagnetic induction, radio waves, and electromagnetic resonance. Thus, it should be understood that any suitable method can be used to recharge the energy storage device 132 from a power source that does not constitute part of the vehicle. In this way, the motor 120 can propel the vehicle by utilizing energy other than the fuel used by the engine 110.

[0026] The energy storage device 132 includes an energy storage device controller 139 and a power distribution module 138. The energy storage device controller 139 provides charge balancing between energy storage elements (e.g., battery cells) and communication with other vehicle controllers (e.g., controller 12). The power distribution module 138 controls the inflow and outflow of electricity in the energy storage device 132.

[0027] 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 unit 107, and door sensing technology 108. The vehicle system 100 may also include an inertial sensor 199. The inertial sensor 199 may include one or more of the following: longitudinal, latitude, vertical, yaw, roll, and pitch sensors (e.g., accelerometers). The axes for yaw, pitch, roll, lateral acceleration, and longitudinal acceleration are as indicated. As an example, the inertial sensor 199 may be coupled to a vehicle constraint control module (RCM) (not shown), which includes a subsystem of the control system 14. The control system may adjust outputs and / or wheel braking in response to the sensor 199 to increase vehicle stability. In another example, the control system may adjust an 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, as well as an active suspension system that controls vehicle height on an individual corner basis (e.g., vehicle height independently controlled at each of the four corners), on an axle basis (e.g., front and rear axle vehicle heights), or controls a single 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 coupled to the controller 12.

[0028] One or more tire pressure monitoring sensors (TPMS) can be attached to one or more tires on the wheels of a vehicle. For example, Figure 1A A tire pressure sensor 197 is shown, which is coupled to and configured to monitor the pressure in the tires of wheels 131a (left) and 131b (right). Although not explicitly stated, it is understood that... Figure 1A Each of the four tires indicated may include one or more tire pressure sensors 197. Additionally, in some instances, 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 stated, it is understood that the pneumatic control unit 123 can be used to control the tires of the wheels. Figure 1AThe control system 14 may inflate or deflate the tires associated with any of the four wheels described herein. For example, in response to an indication of decreased tire pressure, the control system 14 may 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 may command the pneumatic control system unit 123 to deflate one or more tires. In both instances, the pneumatic control system unit 123 may be used to inflate or deflate tires to their optimal tire pressure rating, thereby extending tire life.

[0029] One or more tire speed sensors (WSS) 195 may be coupled to one or more wheels of the vehicle propulsion system 100. The tire speed sensors detect the rotational speed of each wheel. This example of a WSS may include a permanent magnet type sensor.

[0030] The vehicle propulsion system 100 may additionally include an accelerometer 20. The vehicle propulsion system 100 may additionally include an inclinometer 21.

[0031] The vehicle propulsion system 100 may additionally 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 operation by its own power.

[0032] The vehicle propulsion system 100 may additionally include a brake system control module (BSCM) 141. In some instances, the BSCM 141 may include an anti-lock braking system (ABS) such that the wheels (e.g., 130a (left) and 130b (right), 131a (left) and 131b (right)) can maintain traction contact with the road surface during braking based on driver input, thereby preventing wheel lock-up and thus preventing skidding. In some instances, the BSCM may receive input from wheel speed sensors 195. The BSCM may selectively monitor and activate ABS regulating valves 168a to 169b. ABS regulating valves 168a to 168b adjust the hydraulic pressure applied to the brakes 196 of the front wheels 130a (left) and 130b (right). ABS regulating valves 169a to 169b adjust the hydraulic pressure applied to the brakes 196 of the rear wheels 131a (left) and 131b (right).

[0033] The vehicle propulsion system 100 may additionally include a belt-driven starter / generator (BISG) 142. The BISG generates electrical power when the engine 110 is in operation, and this generated electrical power can be used to power electrical devices and / or to charge the onboard storage device 132. For example... Figure 1AThe instructions state that the second inverter system controller (ISC2) 143 can receive AC power from the BISG 142 and can convert the AC power generated by the BISG 142 into DC power for storage in the energy storage device 132. The integrated starter / generator 142 can also provide torque to the engine 110 to supplement engine torque during engine start-up or other conditions.

[0034] In some instances, the vehicle propulsion system 100 may include one or more motors 135a and 135b to propel the vehicle 121 or to provide regenerative braking via the front wheels 130a (left) and 130b (right). Friction brakes 196 may be applied to decelerate the front wheels 130a (left) and 130b (right). A third inverter (ISC3) 147a may convert AC power generated by motor 135a into DC power for storage in energy storage device 132, or supply AC power to motor 135a to propel the vehicle 121. Similarly, a fourth inverter (ISC4) 147a may convert AC power generated by motor 135b into DC power for storage in energy storage device 132, or supply AC power to motor 135b to propel the vehicle 121. Motors 135a and 135b may be collectively referred to as the front wheel motors. Alternatively, a single front wheel motor can provide regenerative braking drive and / or supply power to both front wheels 130a (left) and 130b (right), such as Figure 1C As shown in the image.

[0035] The vehicle propulsion system 100 may additionally include a power distribution box (PDB) 144. The PDB 144 can be used to deliver electrical power to various circuits and accessories throughout the vehicle's electrical system.

[0036] The vehicle propulsion system 100 may additionally include a high-current fuse box (HCFB) 145 and may include a variety of fuses (not shown) for protecting the wiring and electrical components of the vehicle propulsion system 100.

[0037] The vehicle propulsion system 100 may additionally include a motor electronics coolant pump (MECP) 146. The MECP 146 is used to circulate coolant to dissipate heat generated by at least the motor 120 and electronic systems of the vehicle propulsion system 100. As an example, the MECP may receive electrical power from an onboard energy storage device 132.

[0038] Controller 12 may include part of control system 14. In some instances, 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, onboard camera 105, seat load unit 107, door sensing technology 108, inertial sensor 199, etc. In some instances, 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, such as information about... Figure 1B , Figure 2 as well as Figure 3 A more detailed discussion follows.

[0039] The vehicle propulsion system 100 may additionally include a positive temperature coefficient (PTC) heater 148. As an 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, when the element heats up and reaches a threshold temperature, the resistance can become very high, and thus, a large amount of heat can no longer be generated. Therefore, the PTC heater 148 can be self-regulating and has a good degree of protection against overheating.

[0040] The vehicle propulsion system 100 may additionally include an air conditioning compressor module 149, which is used to control an electrical air conditioning compressor (not shown).

[0041] The vehicle propulsion system 100 may additionally include a vehicle audible speaker (VASP) 154 for pedestrians. For example, the VASP 154 may be configured to generate an audible sound via a speaker 155. In some instances, the audible sound generated via the VASP 154, which communicates with the speaker 155, may be activated in response to a sound triggered by the vehicle driver, or automatically in response to an engine speed below a threshold or the detection of a pedestrian.

[0042] The vehicle propulsion system 100 may also include an in-vehicle navigation system 17 (e.g., a Global Positioning System) on the dashboard 19, with which the vehicle's driver can interact. 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 from the signals. In some instances, the geographic coordinates may be transmitted to the controller 12.

[0043] The instrument panel 19 may additionally include a display system 18 configured to display information to the vehicle driver. As a non-limiting example, the display system 18 may include a touchscreen or a human-machine interface (HMI), enabling the vehicle driver to view graphical information and input commands. In some instances, the display system 18 may be wirelessly connected to the Internet (not shown) via a controller (e.g., 12). Thus, in some instances, the vehicle driver may communicate with Internet websites or software applications (apps) via the display system 18.

[0044] The instrument panel 19 may additionally include a driver interface 15, through which the vehicle driver can adjust the vehicle's operating status. Specifically, the driver 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, and electric motor 120) based on driver input. Various examples of the driver ignition interface 15 may include an interface requiring a physical device, such as an active key, which may be inserted into the driver ignition interface 15 to start the engine 110 and start the vehicle, or may be removed to turn off the engine 110 and shut down the vehicle. Other examples may include a passive key communicatively coupled to the driver ignition interface 15. The passive key may be configured as an electronic key card or smart key that does not need to be inserted into or removed from the ignition interface 15 to operate the vehicle engine 110. Instead, the passive key may need to be located inside or near the vehicle (e.g., within a threshold distance of the vehicle). Other instances may additionally or optionally use a start / stop button, which is manually pressed by the driver to start or stop engine 110 and switch the vehicle on or off. In other instances, remote engine start may be initiated by a remote computing device (not shown), such as a cellular phone or smartphone-based system, where the user's cellular phone sends data to a server and the server communicates with vehicle controller 12 to start the engine. The controller (e.g., 12, 111b, 139, etc.) receives data from... Figures 1A to 3 Various sensors receive signals, and based on the received signals and instructions stored in the controller's memory, they employ... Figures 1A to 3 Various actuators are used to adjust vehicle operation.

[0045] refer to Figure 1B A detailed view of an internal combustion engine 110 comprising multiple cylinders is shown, wherein one of the multiple cylinders is in Figure 1BAs shown in the diagram. Engine 110 is controlled by an electronic engine controller 111B. Engine 110 includes a combustion chamber 30B and a cylinder wall 32B, the cylinder wall having a piston 36B positioned therein and connected to a 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 and exhaust valve can be operated by an intake cam 51B and an exhaust cam 53B. The position of intake cam 51B can be determined by an intake cam sensor 55B. The position of exhaust cam 53B can be determined by an exhaust cam sensor 57B. Intake cam 51B and exhaust cam 53B are movable relative to crankshaft 40B. Intake valves can be deactivated and held in a closed state via intake valve deactivation mechanism 59B. Exhaust valves can be deactivated and held in a closed state via exhaust valve deactivation mechanism 58B.

[0046] Fuel injector 66B is shown positioned to inject fuel directly into cylinder 30B, which is referred to by those skilled in the art as direct injection. Alternatively, fuel may be injected into the intake port, which is referred to by those skilled in the art as port injection. 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 tank 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 air intake port 42B to intake manifold 44B. Throttle valve 62B regulates airflow from air filter 43B in engine intake port 42B to intake manifold 44B. In some instances, the throttle body 62B and the throttle plate 64B may be positioned between the intake valve 52B and the intake manifold 44B, such that the throttle body 62B is a port throttle body.

[0047] The distributorless ignition system 88B, in response to the engine controller 111B, supplies an ignition spark to the combustion chamber 30B via the spark plug 92B. A universal exhaust oxygen sensor (UEGO) 126B is shown coupled to the exhaust manifold 48B upstream of the catalytic converter 70B in the direction of exhaust flow. Alternatively, a dual-state exhaust oxygen sensor may replace the UEGO sensor 126B.

[0048] 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 three-way catalyst.

[0049] Engine controller 111B in Figure 1BThe microcomputer shown herein is a conventional microcomputer, including: a microprocessor unit 102B, an input / output port 104B, a read-only memory 106B (e.g., non-transitory memory), a random access memory 108B, a keep-alive memory 110B, and a conventional data bus. Other controllers mentioned herein may have similar processor and memory configurations. The engine controller 111B is shown receiving various signals from sensors coupled to the engine 110, in addition to those previously discussed, including: engine coolant temperature (ECT) from a temperature sensor 112B coupled to a cooling sleeve 114B; a measurement of engine manifold pressure (MAP) from a pressure sensor 122B coupled to an intake manifold 44B; an engine position sensor from a Hall effect sensor 118B sensing the position of the crankshaft 40B; a measurement of the mass of air entering the engine from a sensor 120B; and a measurement of the throttle position from a sensor 58B. Atmospheric pressure may also be sensed (sensor not shown) for processing by the engine controller 111B. In a preferred aspect of this specification, the engine position sensor 118B generates a predetermined number of equidistant pulses at each revolution of the crankshaft, from which the engine speed (RPM) can be determined. The engine controller 111B can receive input from a human / machine interface 115B (e.g., a button or touchscreen display).

[0050] During operation, each cylinder in engine 110 typically undergoes a four-stroke cycle: the cycle includes an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke. During the intake stroke, generally, the exhaust valve 54B is closed and the intake valve 52B is open. Air is introduced into combustion chamber 30B via 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 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 point at the end of its stroke where piston 36B is 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, thereby initiating combustion. During the expansion stroke, the expanding gas pushes piston 36B back to the BDC. Crankshaft 40B converts the piston movement into rotational torque of the rotating shaft. Finally, during the exhaust stroke, exhaust valve 54B opens to release the combusted air-fuel mixture into exhaust manifold 48B and piston returns to the TDC. Note that the above is only shown as an example, and the opening and / or closing timing of the intake and exhaust valves can vary, for example, to provide positive or negative valve overlap, late intake valve closing, or various other instances.

[0051] Figure 1C A schematic diagram of an alternative hybrid vehicle powertrain. Figure 1C The hybrid vehicle powertrain shown in the figure is related to Figure 1A The same parts shown in the figure are used for the same parts. Figure 1A The same number is used for identification. For Figure 1C The configuration identifies each component with a new part number. In this configuration, the hybrid vehicle drivetrain includes a front axle 133. An electric motor 135c can provide positive or negative torque to the front wheels 130a (left) and 130b (right) via a front drive unit 137, which may include a differential. Alternatively, positive or negative torque can be provided to the front wheels 130a (left) and 130b (right) via an all-wheel drive transfer case 177, which may be coupled to a transmission 125. In some instances, the electric motor 135c and the front drive unit 137 are considered part of the front axle 133. Thus, the front axle 133 can provide regenerative braking or torque to propel the vehicle 121. Additionally, the electric motor 135c can receive electrical power from or provide electrical power to an energy storage device 132. The front axle 133 may be referred to as a separate drive axle. Figure 1CThe other components shown can operate as previously described.

[0052] Figure 2 A block diagram of a vehicle 121 including a powertrain or transmission system 200. Figure 2 The power transmission system includes Figures 1A to 1C Engine 110 is shown in the image. Figure 2 and Figure 1A and Figure 1C Other common components are indicated by the same numbers 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., the torque output of the controlled device or component that cannot be exceeded), torque input limits (e.g., the torque input of the controlled device or component that cannot be exceeded), torque output of the controlled device, sensor actuator data, and diagnostic information (e.g., information about a degraded transmission, information about a degraded engine, information about a degraded electric motor, and information about a degraded brake). Additionally, 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.

[0053] For example, in response to the driver releasing the accelerator pedal and the vehicle speed decreasing, the vehicle system controller 12 may request a desired wheel torque or wheel power level to provide a desired wheel deceleration rate. The desired wheel torque may be provided by the vehicle system controller 12 requesting a first braking torque from the motor controller 252 and a second braking torque from the brake controller 141, the first torque and the second torque providing braking regulation torque at wheels 131a (left) and 131b (right).

[0054] In other examples, the partitions controlling the powertrain system can be related to... Figure 2 The different partitioning methods described herein. For example, a single controller can replace vehicle system controller 12, engine controller 111B, motor controller 252, transmission controller 254, and brake controller 141. Alternatively, vehicle system controller 12 and engine controller 111B can be a single unit, while motor controller 252, transmission controller 254, and brake controller 141 can be independent controllers.

[0055] In this example, the powertrain 200 can be powered by an engine 110 and an electric motor 120. In other examples, the engine 110 may be omitted. The engine 110 can be started via a belt-driven starter / generator (BISG) 142 or via an engine starter (e.g., 140) via the electric motor 120. In some examples, the BISG 142 can be directly coupled to the engine crankshaft at either end (e.g., front or rear). 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. Additionally, the torque of the engine 110 can be adjusted via a torque actuator 204, such as a fuel injector, throttle valve, etc.

[0056] BISG 142 is mechanically connected to engine 110 via belt 231. BISG 142 may be connected to a crankshaft (not shown) or a camshaft (not shown). When electrical power is supplied via energy storage device 132, which is also referred to herein as on-board energy storage device 132, BISG 142 may function as a motor. BISG 142 may also function as a generator supplying electrical power to energy storage device 132.

[0057] The drivetrain 200 includes an engine 110, which is 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 supply torque to wheels 131a (left) and 131b (right). A transmission controller 254 selectively engages and disengages the first clutch 126 and the second clutch 127 to shift gears in the DCT 125.

[0058] The transmission 128 may include multiple gears. One clutch, such as a first clutch 126, controls odd-numbered gears 261 (e.g., first, third, fifth, and reverse), while another clutch, such as a second clutch 127, controls even-numbered gears 262 (e.g., second, fourth, and sixth). By utilizing this arrangement, gears can be changed without interrupting the power flow from the engine 110 to the dual-clutch transmission 125.

[0059] The motor 120 can be operated to provide torque to the powertrain 200, or in regenerative mode to convert 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 motor (e.g., 140) or BISG 142 depicted in the diagram has a higher output torque capacity. Additionally, the motor 120 directly drives the powertrain 200 or is driven directly through the powertrain 200.

[0060] 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 via a gear set in the rear drive unit 136. Figure 1A (As shown in the image) It is mechanically connected to wheels 131a (left) and 131b (right) and a dual-clutch transmission. The motor 120 can provide positive or negative torque to the powertrain 200 via acting as a motor or generator as instructed by the motor controller 252.

[0061] Additionally, friction can be applied to wheels 131a (left) and 131b (right) by engaging friction wheel brakes 218. In one example, friction wheel brakes 218 may be engaged in response to the driver pressing their foot on the brake pedal (e.g., 192) and / or in response to a command within the brake controller 141. Furthermore, the brake controller 141 may apply brakes 218 in response to information and / or requests made by the vehicle system controller 12. Similarly, friction on wheels 131a (left) and 131b (right) can be reduced by disengaging wheel brakes 218 in response to the driver releasing their foot from the brake pedal, brake controller commands, and / or vehicle system controller commands and / or information. For example, vehicle brakes may apply friction to wheels 131a (left) and 131b (right) via controller 141 as part of an automated engine stop process.

[0062] The vehicle system controller 12 can also transmit vehicle suspension settings to the suspension controller 280. The suspension of vehicle 121 (e.g., 111) can be adjusted to precisely dampen, over-damp, or under-damp the vehicle suspension via the variable damper 281.

[0063] Therefore, torque control of various powertrain components can be monitored by the vehicle system controller 12, wherein local torque control for the engine 110, transmission 125, motor 120 and brake 218 is provided via the engine controller 111B, motor controller 252, transmission controller 254 and brake controller 141.

[0064] As an example, engine torque output can be controlled by adjusting a combination of spark timing, fuel pulse width, fuel pulse timing, and / or air charging; controlling throttle opening (e.g., 62B) and / or valve timing, valve lift, and boost for turbocharged or supercharged engines. 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 air charging. In various cases, engine control can be performed on a cylinder-by-cylinder basis to control engine torque output.

[0065] The motor controller 252 can control the torque output and electrical energy generation from the motor 120 by adjusting the current flowing to and / or from the armature windings of the motor 120 and the current flowing out therefrom, as is known in the art.

[0066] The transmission controller 254 may receive transmission output shaft torque from torque sensor 272. Alternatively, sensor 272 may be a position sensor or a torque and position sensor. If sensor 272 is a position sensor, then transmission controller 254 may count shaft position pulses at predetermined time intervals to determine transmission output shaft speed. Transmission controller 254 may also differentiate the transmission output shaft speed to determine transmission output shaft acceleration. Transmission controller 254, engine controller 111B, and vehicle system controller 12 may also receive additional transmission information from sensor 277, which may include, but is not limited to, pump output line pressure sensor, transmission hydraulic pressure sensor (e.g., gear clutch fluid pressure sensor), motor temperature sensor, BISG temperature, shift selector position sensor, synchronizer position sensor, and ambient temperature sensor. The transmission controller may also receive requested transmission status (e.g., requested gear or parking mode) from shift selector 279, which may be a lever, switch, or other device.

[0067] The brake controller 141 receives wheel speed information via wheel speed sensor 195 and brake requests from vehicle system controller 12. The brake controller 141 can also receive information directly or via CAN 299 from... Figure 1AThe brake pedal sensor (e.g., 157) shown receives brake pedal position information. Brake controller 141 can provide braking in response to wheel torque commands from vehicle system controller 12. Brake controller 141 can also provide anti-lock braking and vehicle stability braking to improve vehicle braking and stability. Thus, brake controller 141 can provide wheel torque limits (e.g., a threshold negative wheel torque not to be exceeded) to vehicle system controller 12 such that negative motor torque does not cause the wheel torque limit to be exceeded. For example, if controller 12 issues a negative wheel torque limit of 50 N-m, then the motor torque can be adjusted to provide a negative torque of less than 50 N-m (e.g., 49 N-m) at the wheels, including causing transmission gearing.

[0068] Positive torque can be delivered to wheels 131a (left) and 131b (right) in a direction that begins at engine 110 and ends at wheels 131a (left) and 131b (right). Therefore, depending on the direction of the positive torque flow in the drivetrain 200, engine 110 is positioned upstream of transmission 125. Transmission 125 is positioned upstream of motor 120, and BISG 142 can be positioned upstream of engine 110, or downstream of engine 110 and upstream of transmission 125.

[0069] Figure 3 A detailed description of a dual-clutch transmission (DCT) 125 is shown. An engine crankshaft 40B is illustrated as being connected to a clutch housing 393. Alternatively, a shaft may be used to connect the crankshaft 40B to the clutch housing 393. The clutch housing 393 is rotatable in response 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 correspondingly associated first clutch plates 390 and second clutch plates 391. In some instances, the clutch may include a wet clutch immersed in oil (for cooling) or a dry-plate clutch. Engine torque may be transmitted from the clutch housing 393 to either the first clutch 126 or the second clutch 127. The first transmission clutch 126 transmits torque between the engine 110 (shown in 1A) and the first transmission input shaft 302. Thus, the clutch housing 393 may be referred to as the input side of the first transmission clutch 126, and 126A may be referred to as the output side of the first transmission clutch 126. The second transmission clutch 127 transmits torque between the engine 110 (shown in 1A) and the second transmission input shaft 304. Thus, 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.

[0070] The transmission 128 may include multiple gears, as discussed above. There are two transmission input shafts, 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 instance, 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 position 308 for receiving a second gear position 322 or a reverse gear position 328, and may additionally include a fourth fixed gear position 316 for receiving a fourth gear position 326 or a sixth gear position 330. It is understood that the first transmission input shaft 302 and the second transmission input shaft 304 may be correspondingly connected to each of the first clutch 126 and the second clutch 127 via a spine (not shown) on the outer side of each shaft. In a normal resting state, each of the first clutch 302 and the second clutch 304 remains open, for example via a spring (not shown), such that when each of the respective clutches is open, no torque from the engine (e.g., 110) can be delivered to the first transmission input shaft 302 or the second transmission input shaft 304. In response to disengaging the first clutch 126, engine torque can be delivered to the first transmission input shaft 302, and in response to disengaging the second clutch 127, engine torque can be delivered to the second transmission input shaft 304. During normal operation, the transmission electronics ensure that only one clutch is engaged at any given time.

[0071] The transmission 128 may further 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 example 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 respectively transmit torque to the gear 353 via a first output pinion 350 and a second output pinion 352. In this way, the two countershafts can transmit torque to the 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 drive unit 136 (…). Figure 1A(as shown in the diagram), the rear drive unit can cause the drive wheels (e.g., Figure 1A Each of 131a (left) and 131b (right) rotates at a different speed, for example, when performing steering maneuvers.

[0072] As discussed above, each of the following gears—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 freely rotatable. Thus, the synchronizer can be used to match the speed of each gear to the countershaft and can also be used to lock the gears. In example DCT 125, four synchronizers are described, such as first synchronizer 370, second synchronizer 374, third synchronizer 380, and fourth synchronizer 382. First synchronizer 370 includes a corresponding first selector fork 372, second synchronizer 374 includes a corresponding selector fork 376, third synchronizer 380 includes a corresponding third selector fork 378, and fourth synchronizer 384 includes a corresponding fourth selector fork 382. Each of the selector forks allows the movement of each corresponding synchronizer to lock or 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 fifth gear 326 or reverse gear 328. In each case, the movement of the synchronizer can be achieved via selector forks (e.g., 372, 376, 378, and 382) that move each of the corresponding synchronizers to the desired position.

[0073] The movement of the synchronizer via the selector fork can be implemented via the transmission control module (TCM) 254 and the shift fork actuator 388, wherein the TCM 254 may include the components described above. Figure 2The TCM 254 is discussed. The shift fork actuator can be operated electrically, hydraulically, or in a combination of both. Hydraulic power can be provided via pump 312 and / or pump 367. The TCM 254 can collect input signals from various sensors, access inputs, and control various actuators accordingly. Inputs utilized by the TCM 254 may include, but are not limited to, transmission range (P / R / N / D / S / L, etc.), vehicle speed, engine speed and torque, throttle position, engine temperature, ambient temperature, steering angle, brake input, transmission input shaft speed (both the first transmission input shaft 302 and the second transmission input shaft 304), and vehicle posture (tilt). The TCM can control the actuators via open-loop control to allow adaptive control. For example, adaptive control allows the TCM 254 to identify and adapt to clutch engagement points, clutch friction coefficients, and synchronizer assembly positions. The TCM 254 can also adjust the first clutch actuator 389 and the second clutch actuator 387 to open and close 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 in a combination of electrical and hydraulic means. Hydraulic power can be provided via pump 312 and / or pump 367.

[0074] Therefore, TCM 254 is described as receiving input from various sensors 277. (As mentioned above...) Figure 2 The various sensors discussed may include pump output line pressure sensors, transmission hydraulic pressure sensors (e.g., gear clutch fluid pressure sensors), motor temperature sensors, shifter position sensors, synchronizer position sensors, and ambient temperature sensors. Various sensors 277 may further include wheel speed sensors (e.g., 195), engine speed sensors, engine torque sensors, throttle position sensors, engine temperature sensors, steering angle sensors, transmission shift fork position sensors for detecting the position of selector forks (e.g., 372, 376, 378, 382), and inertial sensors (e.g., 199). Inertial sensors may include one or more of the following: longitudinal, latitude, vertical, yaw, roll, and pitch sensors, as described above regarding... Figure 1A The discussion.

[0075] Sensor 277 may additionally include an input shaft speed (ISS) sensor, which may include a magnetoresistive sensor, and wherein each transmission input shaft may include one ISS sensor (e.g., one for the first transmission input shaft 302 and one for the second transmission input shaft 304). Sensor 277 may additionally 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 additionally include a transmission range (TR) sensor.

[0076] DCT 125 can be understood to function as described herein. For example, when the first clutch 126 is engaged, engine torque can be supplied to the first transmission input shaft 302. When the first clutch 126 is engaged, it is understood that the second clutch 127 is engaged, and vice versa. Depending on which gear is locked when the first clutch 126 is engaged, power can be delivered via the first transmission input shaft 302 to the first countershaft 340 or the second countershaft 342, and additionally via the first pinion 350 or the second pinion 352 to the output shaft 362. Alternatively, when the second clutch 127 is engaged, depending on which gear is locked, power can be delivered via the second transmission input shaft 304 to the first countershaft 340 or the second countershaft 342, and additionally via the first pinion 350 or the second pinion 352 to the output shaft 362. Understandably, when torque is transmitted to one secondary shaft (e.g., the first output shaft 340), another secondary shaft (e.g., the second output shaft 342) can continue to rotate, even if only one shaft is directly driven by the input. More specifically, the non-engaged shaft (e.g., the second secondary shaft 342) can continue to rotate because it is indirectly driven via output shaft 362 and a corresponding pinion (e.g., 352).

[0077] The DCT 125 allows for gear pre-selection, thus enabling rapid gear shifting with minimal torque loss during gear changes. As an example, when the first gear 320 is locked via the first synchronizer 340, and the first clutch 126 is closed (and the second clutch 127 is open), power can be delivered 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 be simultaneously locked via the second synchronizer 374. Because the second gear 322 is locked, this allows the second input shaft 304 to rotate, whereby the second input shaft 304 is speed-matched to the vehicle speed in the second gear. In the alternative scenario where a gear is pre-selected on another countershaft (e.g., the second countershaft 342), the countershaft will also rotate, as it is driven by the output shaft 362 and pinion 352.

[0078] When shifting gears via TCM 254, only the clutches need to be engaged to disengage the first clutch 126 and disengage the second clutch 127. Additionally, outside the TCM, the engine speed can be reduced to match the upshift. With the second clutch 127 disengaged, power can be delivered to the engine, to the input shaft 304 and to the first countershaft 340, and additionally to the output shaft 362 via pinion 350. After the gear shift is complete, TCM 254 can pre-select the next gear appropriately. For example, TCM 254 can pre-select a higher or lower gear based on inputs received from various sensors 277. In this way, gear changes can be achieved quickly with minimal loss of engine torque to the output shaft 362.

[0079] In some instances, the dual-clutch transmission 300 may include a parking gear position 360. A parking pawl 363 may face the parking gear position 360. When the shift lever is set to park, the parking pawl 363 may engage the parking gear position 360. Engagement of the parking pawl 363 with the parking gear position 360 may be achieved via a parking pawl spring 364, or via a cable (not shown), a hydraulic piston (not shown), or a motor (not shown), etc. When the parking pawl 363 is engaged with the parking gear position 360, the drive wheels of the vehicle (e.g., 130a (left) and 130b (right), 131a (left) and 131b (right)) may be locked. On the other hand, in response to the shift lever moving from park to another selection (e.g., drive), the parking pawl 363 may move such that the parking pawl 363 may disengage from the parking gear position 360.

[0080] In some instances, the electric transmission pump 312 supplies hydraulic fluid from the transmission oil pan 311 to a compression spring 364 to release the parking pawl 363 from the parking position 360. The electric transmission pump 312 may be powered, for example, by an onboard energy storage device (e.g., 132). In some instances, a mechanical pump 367 may additionally or alternatively supply hydraulic fluid from the transmission oil pan 311 to a compression spring 364 to release the parking pawl 363 from the parking position 360. Although not explicitly stated, the mechanical pump may be driven by an engine (e.g., 110) and may be mechanically connected to the clutch housing 393. In some instances, a parking pawl valve 361 regulates the flow of hydraulic fluid to the spring 364.

[0081] therefore, Figures 1A to 3The system provides a vehicle system including: an anti-lock braking system (ABS) including four friction brakes; a first motor; a second motor; and a controller including executable instructions stored in a non-transitory memory, the executable instructions causing the controller to filter wheel torque of a first axle via a first low-pass filter having a first cutoff frequency, and to filter wheel torque of a second axle via a second low-pass filter having a second cutoff frequency. The vehicle system further includes additional instructions for adjusting the regenerative torque of the main axle to a lower value than the low-pass filtered main axle-adjusted torque of the right wheel and the low-pass filtered main axle-adjusted torque of the left wheel. The vehicle system further includes additional instructions for adjusting the regenerative torque of the secondary axle to a lower value than the low-pass filtered secondary axle-adjusted torque of the right wheel and the low-pass filtered secondary axle-adjusted torque of the left wheel. The vehicle system further includes additional instructions for applying at least one of the four friction brakes in response to activation of the ABS. The vehicle system includes a first cutoff frequency lower than the second cutoff frequency. The vehicle system includes a first cutoff frequency based on both the inertia of a first motor and the smoothness of its powertrain, a second cutoff frequency based on both the inertia of a second motor and the smoothness of its powertrain, and wherein the first and second motors provide torque to the vehicle drivetrain.

[0082] Now for reference Figure 4 This illustrates an example method for operating a hybrid powertrain to improve powertrain efficiency via regeneration. Figure 4 The method can be incorporated into Figures 1A to 3 And in the system and collaborate with the system. Additionally, Figure 4 At least a portion of the method can be incorporated as executable instructions stored in non-transitory memory, while other portions of the method can be executed via a controller that transforms the operational state of real-world devices and actuators. Figure 4 The frictional braking torque and regenerative braking torque described in the method can be applied to reduce wheel speed. Instructions for implementing method 400 can be executed by a controller based on instructions stored in the controller's memory and in conjunction with signals received from sensors of the engine system, such as those referenced above. Figures 1A to 3 The sensor described. According to the method described below, the controller can employ the engine actuators of the engine system to adjust engine operation.

[0083] At 402, method 400 determines whether the vehicle brake pedal is applied. Method 400 may determine that the brake pedal is applied in response to the position of the brake pedal, as determined by a brake pedal position sensor. If method 400 determines that the brake pedal is applied, then the answer is yes and method 400 proceeds to 404. Otherwise, the answer is no and method 400 proceeds to exit.

[0084] At 404, method 400 monitors the operational status of the anti-lock braking system (ABS) control valve for each wheel. Specifically, method 400 determines whether one of the ABS control valves is active or deactivated. An ABS control valve may be activated if wheel lock-up is detected during braking. An ABS control valve may be deactivated if wheel lock-up is not detected during braking. Method 400 proceeds to 406.

[0085] At 406, method 400 determines whether at least one anti-lock braking system (ABS) control valve is active. Method 400 may determine whether one or more ABS control valves are active based on the amount of current supplied to the ABS control valve, brake line pressure, or other known methods. If method 400 determines that at least one ABS control valve is active, then the answer is yes and method 400 proceeds to 408. Otherwise, the answer is no and method 400 proceeds to 440.

[0086] At 440, method 400 determines the regenerative braking torque of the vehicle's main axle. In one example, the vehicle's main axle is the axle of the vehicle that receives all drivetrain power when no wheel slippage is detected. Figures 1A to 1C In this system, the vehicle's main axle is the rear axle, or the axle that drives the rear wheels. The secondary axle is the front axle, or the axle that drives the front wheels. In one example, the larger of the following is determined: the requested braking torque (e.g., the braking torque requested by a human driver), the motor torque limit (e.g., the maximum negative motor torque), the battery torque charging limit (e.g., the maximum torque provided by the motor when the motor torque is limited to the maximum current that the vehicle's traction battery can receive), and the main axle's vehicle stability torque limit (e.g., the maximum wheel torque for stable vehicle operation). The requested braking torque, motor torque limit, battery torque charging limit, and main axle's vehicle stability torque limit are all negative. Therefore, the maximum value of the parameter is the value closest to zero. For example, if the requested braking torque is -400 N-m, the motor torque limit is -600 N-m, the battery charging torque limit is -550 N-m, and the main shaft vehicle stability torque limit is -500 N-m, then method 400 selects the requested braking torque because the value of the requested braking torque, -400 N-m, is greater than the values ​​-600, -550, and -500. The regenerative braking torque of the main shaft can be determined by the following equation:

[0087] Tq_regen_PDAxle=max(Tq_brakeReq,Tq_mtrLim,Tq_battChrgLim,

[0088] Tq_vehStabLim_PDAxle)

[0089] Where Tq_regen_PDAxle is the regenerative braking torque of the main shaft, Tq_brakeReq is the braking torque requested by a human or autonomous driver, Tq_mtrLim is the motor torque limit, which may include the RDU motor and ISG / BISG, Tq_battChrgLim is the battery charging torque limit (e.g., the regenerative braking torque at which the battery cannot accept a higher charging rate), and Tq_vehStabLim_PDAxle is the main shaft torque limit used to maintain vehicle stability. Method 400 proceeds to 442.

[0090] At 442, method 400 determines the regenerative braking torque of the vehicle's secondary axle. In one example, the vehicle's secondary axle is the axle that can receive power from the drivetrain when positive drivetrain torque causes wheel slippage, but the secondary axle may not receive positive power from the drivetrain when wheel slippage is not detected. Figures 1A to 1C In this system, the vehicle's sub-axle is the front axle, or the axle that drives the front wheels.

[0091] Method 400 determines the possible regenerative braking torque of a vehicle including a main axle and a secondary axle. In one example, the possible regenerative braking torque is determined to be the larger of the requested braking torque, the motor torque limit, and the battery torque charging limit. The requested braking torque, the motor torque limit, and the battery torque charging limit are all negative values. The possible vehicle regenerative braking torque can be determined via the following equation:

[0092] Tq_regen_Pot=max(Tq_brakeReq,Tq_mtrLim,Tq_battChrgLim)

[0093] Where Tq_regen_Pot is the vehicle's possible regenerative braking torque, Tq_brakeReq is the braking torque requested by a human or autonomous driver, Tq_mtrLim is the motor torque limit, which may include the RDU motor and ISG / BISG, and Tq_battChrgLim is the battery charging torque limit (e.g., the battery cannot accept regenerative braking torque at a higher charging rate at this location). Method 400 also determines whether the absolute value of the vehicle's possible regenerative braking torque (Tq_regen_Pot) is greater than the absolute value of the main shaft's regenerative braking torque (Tq_regen_PDAxle). If not, then the secondary shaft's regenerative braking torque is zero. If yes, then the secondary shaft's regenerative braking torque is determined by the following formula:

[0094] Tq_regen_SDAxle=max(Tq_vehStabLim_SDAxle,

[0095] Tq_regen_Pot-Tq_regen_PD_Axle,Tq_AWDtrasfCap)

[0096] Where Tq_regen_SDAxle is the regenerative braking torque of the vehicle's secondary axle, Tq_vehStabLim_SDAxle is the secondary axle torque limit used to maintain vehicle stability, Tq_regen_Pot is the vehicle's possible regenerative braking torque, Tq_regen_PDAxle is the regenerative braking torque of the primary axle, and Tq_AWDtrasfCap is the torque transmission capacity of the all-wheel drive transfer case. Method 400 proceeds to 444.

[0097] At position 444, method 400 determines the friction braking torque. In one example, the friction braking torque is determined via the following equation:

[0098] Tq_fric=Tq_brakeReq-(Tq_regen_PDAxle+Tq_regen_SD_Axle)

[0099] Where Tq_fric is the vehicle's friction braking torque, Tq_brakeReq is the braking torque requested by a human or autonomous driver, Tq_regen_PDAxle is the regenerative braking torque of the main axle, and Tq_regen_SDAxle is the regenerative braking torque of the vehicle's secondary axle. The friction braking torque can be distributed between the front and rear axles of the left and right wheels via a hydraulic adjustment circuit or via a graph or function stored in the vehicle's brake controller memory. Method 400 proceeds to exit.

[0100] At point 408, method 400 determines the braking adjustment torque of the spindle. In one example, the braking adjustment torques of the left and right wheels of the spindle can be determined via the following equation:

[0101] T wheelBrk_i =T regen_i +T frcBrk_i

[0102]

[0103] Where T wheelBrk_i T is the braking torque for wheel i, where i can be left front (fl), right front (fr), left rear (rl), or right rear (rr). regen_i To apply the regenerative torque to wheel i, T frcBrk_i Let ω be the frictional braking torque of wheel i. i Let v be the speed of the i-th wheel, R be the wheel radius, and v ref Let dω be the vehicle reference speed (e.g., the vehicle's speed). i / dt represents the acceleration of the i-th wheel. The braking adjustment torque of each wheel is the sum of the wheel's regenerative braking torque and its frictional braking torque. The wheel's regenerative braking torque can be determined from the motor torque and the gear ratio between the motor and the corresponding wheel. Wheel speed can be determined via a wheel speed sensor, road angle via an inclinometer, and wheel inertia can be determined empirically. The braking adjustment torque of the right wheel of the main axle can be abbrake_brakeRequ_PDAxle_L. The braking adjustment torque of the right wheel of the main axle can be abbrake_brakeRequ_PDAxle_R. Proceed from method 400 to 410.

[0104] At 410, method 400 determines the regenerative braking torque of the spindle. In one example, the regenerative braking torque of the spindle is determined via the following equation:

[0105] Tq_regen_PDAxle=max(lowPassFilter(Tq_brakeRequ_PDAxle_L)*rt_1,lowPassFilter(Tq_brakeRequ_PDAxle_R)*rt_2,Tq_mtrLim,Tq_battChrgLim,Tq_vehStabLim_PDAxle)

[0106] Where Tq_regen_PDAxle is the regenerative braking torque of the main shaft, max is a function that returns the larger value of the parameters input to the function max, lowPassFilter(arg1) is a function that provides the low-pass filtered value of the input y(i)=∝1·x(i)+(1-∝1)·y(i-1)arg1 (e.g., the low-pass filter can be represented as a discrete value of , where y is the low-pass filter output, i is the number of samples, x is the low-pass filter input, and α is the filter factor), and rt_1 is an empirically determined percentage (e.g., 0. 1 or 10%, the percentage can vary from 0 to 100%, rt_2 is an empirically determined percentage (e.g., 0.1 or 10%, the percentage can vary from 0 to 100%), Tq_mtrLim is the motor torque limit that may include the RDU motor and ISG / BISG, Tq_battChrgLim is the battery torque charging limit (e.g., the regenerative braking torque at which the battery cannot accept a higher charging rate), and Tq_vehStabLim_PDAxle is the main shaft torque limit used to maintain vehicle stability. All torque parameters input to the function max are negative torques (e.g., Tq_mtrLim = -500 N-m).

[0107] Therefore, when the values ​​of each variable Tq_mtrLim, Tq_battChrgLim, and Tq_vehStabLim_PDAxle are greater than the values ​​of Tq_brakeRequ_PDAxle_L or Tq_brakeRequ_PDAxle_R, Tq_regen_PDAxle is a low-pass filtered portion of Tq_brakeRequ_PDAxle_L or Tq_brakeRequ_PDAxle_R. By determining Tq_regen_PDAxle as a low-pass filtered portion of the variables Tq_brakeRequ_PDAxle_L or Tq_brakeRequ_PDAxle_R, high frequencies can be eliminated from the spindle regenerative torque, thereby reducing drivetrain noise and vibration. Additionally, empirically determined multipliers rt_1 and rt_2 reduce the regenerative braking torque to ensure that a portion of the braking torque is provided via a highly dynamic friction braking system, thus maintaining braking effectiveness. Method 400 proceeds to 412.

[0108] At position 412, method 400 determines the friction braking torque of the spindle. In one example, method 400 can determine the friction braking torque of the spindle via the following equation:

[0109] Tq_fric_PDAxle_L=Tq_brakeRegu_PDAxle_L-Tq_regen_PDAxle*0.5

[0110] Tq_fric_PDAxle_R=Tq_brakeRegu_PDAxle_R-Tq_regen_PDAxle*0.5

[0111] Where Tq_fric_PDAxle_L is the friction torque of the left wheel of the main shaft, Tq_fric_PDAxle_R is the friction torque of the right wheel of the main shaft, Tq_brakeRegu_PDAxle_L is the regenerative braking torque of the left wheel of the main shaft, Tq_brakeRegu_PDAxle_R is the regenerative braking torque of the right wheel of the main shaft, and Tq_regen_PDAxle is the regenerative braking torque of the main shaft.

[0112] Therefore, the friction torque of the left spindle is the braking adjustment torque of the left spindle minus half of the regenerative braking torque of the left spindle. Similarly, the friction torque of the right spindle is the braking adjustment torque of the right spindle minus half of the regenerative braking torque of the right spindle. Method 400 proceeds to 414.

[0113] At point 414, method 400 determines the braking adjustment torque of the countershaft. In one example, the braking adjustment torques of the left and right wheels of the countershaft can be determined via the following equation:

[0114] T wheelBrk_i =T regen_i +T frcBrk_i

[0115]

[0116] Where T wheelBrk_i T is the braking torque for wheel i, where i can be left front (fl), right front (fr), left rear (rl), or right rear (rr). regen_i To apply the regenerative torque to wheel i, T frcBrk_i Let ω be the frictional braking torque of wheel I. i Let v be the speed of the i-th wheel, R be the wheel radius, and v ref Let dω be the vehicle reference speed (e.g., the vehicle's speed). i / dt represents the acceleration of the i-th wheel. The braking adjustment torque of each wheel is the sum of the wheel's regenerative braking torque and its frictional braking torque. The wheel's regenerative braking torque can be determined from the motor torque and the gear ratio between the motor and the corresponding wheel. Wheel speed can be determined via a wheel speed sensor, road angle via an inclinometer, and wheel inertia can be determined empirically. The braking adjustment torque of the right wheel on the secondary axle can be abbrake_brakeRequ_SDAxle_L. The braking adjustment torque of the right wheel on the secondary axle can be abbrake_brakeRequ_SDAxle_R. Proceed from method 400 to 416.

[0117] At 416, method 400 determines the regenerative braking torque of the secondary shaft. Here, two all-wheel drive (AWD) configurations are discussed: a mechanical AWD using a transfer case, and an AWD implemented via an independent electric motor on each axle (e.g., the primary axle is determined by an engine and electric motor 1, and the secondary axle is driven by electric motor 2). In these two configurations, the determination of the regenerative braking torque of the secondary shaft can be different, as described herein.

[0118] In one instance, method 400 determines the possible regenerative braking torque for an AWD vehicle with a transfer case, including the main axle and the sub-axle, as described herein. In a first configuration, the possible regenerative braking torque is the larger of the motor torque limit (Tq_mtrLim) and the battery torque charging limit (Tq_battChrgLim). The possible vehicle regenerative braking torque can be determined via the following equation:

[0119] Tq_regen_Pot=max(Tq_mtrLim,Tq_battChrgLim)

[0120] Where Tq_regen_Pot is the vehicle’s possible regenerative braking torque, Tq_mtrLim is the motor torque limit that may include the RDU motor and ISG / BISG, and Tq_battChrgLim is the battery charging torque limit (e.g., the battery cannot accept regenerative braking torque at a higher charging rate at this location).

[0121] Method 400 further determines whether the absolute value of the vehicle's possible regenerative braking torque (Tq_regen_Pot) is greater than the absolute value of the main axle's regenerative braking torque (Tq_regen_PDAxle), and whether the front axle is connected to the transmission and rear axle via a transfer case. If not, then the secondary axle's regenerative braking torque is zero. If yes, then the secondary axle's regenerative braking torque is determined by the following equation:

[0122] Tq_regen_SDAxle=max(lowPassFilter(Tq_brakeRequ_SDAxle_L)*rt_3,lowPassFilter1(Tq_brakeRequ_SDAxle_R)*rt_4,Tq_regen_Pot-Tq_regen_PDAxle,Tq_vehStabLim_SDAxle,Tq_AWDtransfCap)

[0123] Where Tq_regen_SDAxle is the regenerative braking torque of the secondary shaft, max is a function that returns the larger value of the parameters input to the function max, lowPassFilter1(arg1) is a function that provides the low-pass filtered value of the input y(i) = ∝1·x(i) + (1-∝1)·y(i-1)arg1 (e.g., y is the filter output, i is the number of samples, x is the filter input, and α is the filter factor, which is the same for the primary and secondary shafts), rt_3 is an empirically determined percentage (e.g., 0.1 or 10%, which can vary from 0 to 100%), and rt_4 is a low-pass filtered value of the input y(i) = ∝1·x(i) + (1-∝1)·y(i-1)arg1. The percentage determined by verification (e.g., 0.1% or 10%, which can vary from 0 to 100%), Tq_brakeRequ_SDAxle_L is the braking adjustment torque of the left wheel of the sub-axle, Tq_brakeRequ_SDAxle_R is the braking adjustment torque of the right wheel of the sub-axle, Tq_regen_Pot is the possible regenerative braking torque of the vehicle, Tq_regen_PDAxle is the regenerative braking torque of the main axle, Tq_vehStabLim_SDAxle is the sub-axle torque limit used to maintain vehicle stability, and Tq_AWDtransfCap is the torque transmission capacity of the transfer case.

[0124] Therefore, when the values ​​of each variable Tq_regen_Pot-Tq_regen_PDAxle, Tq_vehStabLim_SDAxle, and Tq_AWDtransfCap are greater than the values ​​of Tq_brakeRequ_SDAxle_L or Tq_brakeRequ_SDAxle_R, Tq_regen_SDAxle is the low-pass filtered portion of Tq_brakeRequ_SDAxle_L or Tq_brakeRequ_SDAxle_R. By determining Tq_regen_SDAxle as the low-pass filtered portion of the variables Tq_brakeRequ_SDAxle_L or Tq_brakeRequ_SDAxle_R, high frequencies can be eliminated from the regenerated torque of the subshaft, thereby reducing transmission noise and vibration. Furthermore, empirically determined multipliers rt_3 and rt_4 reduce the regenerated braking torque to ensure that a portion of the braking torque is provided via a highly dynamic friction braking system, thus maintaining braking effectiveness.

[0125] In a second AWD configuration with independent motors for the main and secondary shafts, the possible regenerative braking torque (Tq_regen_Pot_SDAxle) of the secondary shaft is the larger of the motor torque limit (Tq_mtrLim_SDAxle) of the secondary shaft and the battery torque charging limit (Tq_battChrgLim) subtracted from the regenerative braking torque (Tq_regen_PDAxle) of the main shaft. The possible regenerative braking torque of the secondary shaft can be determined via the following equation:

[0126] Tq_regen_Pot_SDAxle=max(Tq_mtrLim_SDAxle,Tq_battChrgLim-Tq_regen_PDAxle)

[0127] The regenerative braking torque of the secondary shaft is determined by the following equation:

[0128] Tq_regen_SDAxle=max(lowPassFilter2(Tq_brakeRequ_SDAxle_L)*rt_3,lowPassFilter2(Tq_brakeRequ_SDAxle_R)*rt_4,Tq_vehStabLim_SDAxle,Tq_regen_Pot_SDAxle)

[0129] Where Tq_regen_SDAxle is the regenerative braking torque of the sub-shaft, max is a function that returns the larger value of the parameters input to the function max, lowPassFilter2(arg1) is a function that provides the low-pass filtered value of the input y(i) = ∝2·x(i) + (1-∝2)·y(i-1)arg1 (e.g., y is the filter output, i is the number of samples, x is the filter input, and α2 is the filter factor unique for the sub-shaft), rt_3 is an empirically determined percentage (e.g., 0.1 or 10%, which can vary from 0 to 100%), rt _4 represents an empirically determined percentage (e.g., 0.1% or 10%, which can vary from 0 to 100%), Tq_brakeRequ_SDAxle_L is the braking adjustment torque of the left wheel of the sub-shaft, Tq_brakeRequ_SDAxle_R is the braking adjustment torque of the right wheel of the sub-shaft, Tq_regen_PDAxle is the regenerative braking torque of the main shaft, Tq_vehStabLim_SDAxle is the sub-shaft torque limit used to maintain vehicle stability, and Tq_regen_Pot_SDAxle is the possible regenerative braking torque of the sub-shaft. The low-pass filter factor α2 can be a different value than the low-pass filter α1, allowing the regenerative braking provided by the motor or the machine associated with the main and sub-shafts to be unique for different desired regenerative braking responses. For example, a faster regenerative braking response from the sub-shaft than from the main shaft can be expected. This results in a higher filter cutoff frequency, and therefore a larger value for α2. Note that the cutoff frequency can be chosen as high as the natural frequency of the mechanical system (e.g., the drive shaft); and the natural frequency is determined by its physical system characteristics, such as the inertia of the motor and the smoothness of the powertrain. If the fastest regenerative braking response is guaranteed for both shafts, then the filter factors can be different. For example, assuming the same powertrain smoothness between the main shaft and the secondary shaft, the filter factor α2 for the secondary shaft will be larger due to the smaller motor (or lower inertia). Method 400 proceeds to 418.

[0130] At point 418, method 400 determines the frictional braking torque of the spindle. In one example, method 400 can determine the frictional braking torque of the spindle via the following equation:

[0131] Tq_fric_SDAxle_L=Tq_brakeRegu_SDAxle_L-Tq_regen_SDAxle*0.5

[0132] Tq_fric_SDAxle_R=Tq_brakeRegu_SDAxle_R-Tq_regen_SDAxle*0.5

[0133] Where Tq_fric_SDAxle_L is the friction torque of the left wheel of the secondary axle, Tq_fric_SDAxle_R is the friction torque of the right wheel of the secondary axle, Tq_brakeRegu_SDAxle_L is the regenerative braking torque of the left wheel of the secondary axle, Tq_brakeRegu_SDAxle_R is the regenerative braking torque of the right wheel of the secondary axle, and Tq_regen_SDAxle is the regenerative braking torque of the secondary axle.

[0134] Therefore, the friction torque of the left wheel on the countershaft is the braking adjustment torque of the left wheel on the countershaft minus half of the regenerative braking torque of the left wheel on the countershaft. Similarly, the friction torque of the right wheel on the countershaft is the braking adjustment torque of the right wheel on the countershaft minus half of the regenerative braking torque of the right wheel on the countershaft. Method 400 proceeds to exit.

[0135] therefore, Figure 4 A method provides a vehicle operation method, the method comprising: adjusting the regenerative torque of the main shaft to a lower value between the low-pass filtered main shaft regulating torque of the right wheel and the low-pass filtered main shaft regulating torque of the left wheel in response to activation of the anti-lock braking system. The method further comprises applying a friction brake in response to activation of the anti-lock braking system. The method includes wherein the anti-lock braking system is activated via an activation brake line pressure regulating valve. The method includes wherein the regenerative braking torque of the main shaft is provided via a motor of the rear drive unit. The method further includes adjusting the regenerative torque of the main shaft in response to a requested braking torque provided by a human driver when the anti-lock braking system is not activated. The method includes wherein torque is provided to the main shaft via an engine and a motor. The method further includes adjusting the friction brake of the main shaft to a torque determined by subtracting the regenerative torque of the main shaft from the braking regulating torque of the main shaft.

[0136] Figure 4The method also provides a vehicle operation method, the method comprising: adjusting the regenerative torque of the main shaft to the lower of the low-pass filtered main shaft regulating torque of the right wheel and the low-pass filtered main shaft regulating torque of the left wheel; and adjusting the regenerative torque of the secondary shaft to the lower of the low-pass filtered secondary shaft regulating torque of the right wheel and the low-pass filtered secondary shaft regulating torque of the left wheel. The method includes wherein the regulating torque of the secondary shaft is further adjusted in response to a possible regenerative braking torque. The method further includes adjusting the friction brake of the secondary shaft to a torque determined by subtracting the regenerative torque of the secondary shaft from the braking regulating torque of the secondary shaft, and wherein the cutoff frequency of the low-pass filtered main shaft regulating torque is equal to the cutoff frequency of the low-pass filtered secondary shaft regulating torque. The method includes wherein the cutoff frequency of the low-pass filtered main shaft regulating torque is different from the cutoff frequency of the low-pass filtered secondary shaft regulating torque. The method includes performing the adjustment of the regenerative torque of the main shaft and the regenerative torque of the secondary shaft in response to activation of an anti-lock braking system. The method includes wherein the anti-lock braking system is activated via activation of a brake line pressure regulating valve. The method further includes adjusting the regenerative torque of the spindle in response to a requested braking torque provided by a human driver when the anti-lock braking system is not activated.

[0137] Now for reference Figure 5 , showing according to Figure 4 The predictive vehicle operation sequence of the method. Figure 5 The vehicle operation sequence shown can be accessed via Figure 4 Methods and Figures 1A to 3 The system collaboration shown in the figure is provided. Figure 5 The curves shown appear simultaneously and are aligned in time.

[0138] from Figure 5 The first graph observed at the top is a graph of vehicle speed versus time. The vertical axis represents vehicle speed, and vehicle speed 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.

[0139] from Figure 5 The second graph, viewed from the top, shows the status of the anti-lock braking system (ABS). When the trajectory is at a higher level, closer to the arrow on the vertical axis, the ABS is active and adjusting braking torque. When the trajectory is at a lower level, closer to the horizontal axis, the ABS is inactive and not adjusting braking torque. The horizontal axis represents time, and time increases from the left to the right of the graph.

[0140] from Figure 5The third graph, viewed from the top, is a graph of the vehicle's braking torque request. The braking torque request can be provided by a human driver or an autonomous driver, and it represents the braking torque applied to all four wheels. The braking torque is negative, and its magnitude 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.

[0141] from Figure 5 The fourth graph observed at the top is a graph of the transmitted vehicle braking torque. In this example, the transmitted vehicle braking torque for adjustment is for the wheels on the main axle. The transmitted vehicle braking torque for adjustment is the braking torque applied to the wheels. The horizontal axis represents time, and time increases from the left side of the graph to the right side.

[0142] from Figure 5 The fifth curve observed from the top is a graph of the friction braking torque. The friction braking torque is shown as the sum of the friction braking torque of the main axle and the wheels. The horizontal axis represents time, and time increases from the left side of the graph to the right side.

[0143] from Figure 5 The sixth graph, viewed from the top, is a graph of the motor or regenerative braking torque. The motor braking torque shown is the sum of the frictional braking torques at all four wheels via the RDU motor and / or ISG and / or BISG. Alternatively, if the vehicle includes regenerative braking only at the main axle, then the regenerative braking torque is the regenerative braking torque applied to the wheels at the main axle. The horizontal axis represents time, and time increases from the left side of the graph to the right side. Figure 5 The horizontal axis of the third, fourth, fifth, and sixth curves observed from the top represents zero braking torque.

[0144] At time T0, the vehicle speed is low and vehicle braking is not applied, as indicated by the zero braking torque request. Additionally, the motor torque is zero and the anti-lock braking system (ABS) is not activated. Between time T0 and time T1, the vehicle accelerates while vehicle braking is not performed.

[0145] At time T1, the driver (not shown) applies the brake pedal (not shown) and requests an increase in braking torque in response to the brake pedal position (not shown). The friction brakes are not applied, but the motor begins to provide braking torque. The braking torque transmitted for adjustment follows the braking torque request. Between time T0 and time T1, the magnitude of the requested braking torque increases, and the magnitude of the braking torque transmitted for adjustment increases to follow the braking torque request. The vehicle decelerates, but the anti-lock braking system is not activated. The friction brakes are not applied.

[0146] At time T2, the anti-lock braking system (ABS) is activated in response to wheel speed, as indicated by the ABS state transition to a higher level. The friction brakes are activated and the friction braking torque increases. The electric motor torque or regenerative braking torque decreases in response to ABS activation. By reducing the electric motor torque and activating the friction brakes, wheel rotation can continue or resume, allowing braking efficiency to be maintained or improved. The braking torque request remains at its previous value because the driver input has not changed.

[0147] Between time T2 and time T3, the motor torque or regenerative braking torque is adjusted to the low-pass filtered value of the braking adjustment torque of the right or left main shaft. The friction braking torque of the main left wheel is the adjustment torque of the main left wheel minus half of the regenerative torque of the main shaft. The friction braking torque of the main right wheel is the adjustment torque of the main right wheel minus half of the regenerative torque of the main shaft.

[0148] At time T3, the ABS is deactivated in response to a decrease in the magnitude of the requested braking torque or the end of wheel slippage. The magnitude of the electric braking torque or regenerative braking torque is increased to provide the requested braking torque. The braking torque transmitted for adjustment is equal to the requested braking torque, and the friction brakes are deactivated.

[0149] In this way, wheel braking torque can be distributed between regenerative braking and friction braking. If wheel lock-up is detected via activation of the ABS braking system, regenerative braking can be reduced while friction braking is activated.

[0150] Note that the example control and estimation routines included herein can be used in various engine and / or vehicle system configurations. The control methods and routines disclosed herein can be stored as executable instructions in non-transitory memory and can be implemented by a control system including a controller in conjunction with various sensors, actuators, and other engine hardware. Furthermore, portions of the methods can be physical actions taken in the real world to change the state of a device. The specific routines described herein can represent one or more of any number of processing strategies, such as event-driven, interrupt-driven, multitasking, multithreading, etc. Thus, the various actions, operations, and / or functions described can be executed sequentially, simultaneously, or omitted in some cases. Similarly, the order of processing is not necessary to achieve the features and advantages of the example instances described herein, but rather provides ease of explanation and description. Depending on the specific strategy used, one or more of the described actions, operations, and / or functions can be repeatedly performed. Additionally, the described actions, operations, and / or functions can be visually represented as code to be programmed into a non-transitory memory of a computer-readable storage medium in an engine control system, wherein the described actions are implemented by executing instructions in conjunction with an electronic controller in a system including various engine hardware components. One or more of the method steps described in this article may be omitted if necessary.

[0151] It should be understood that the configurations and routines disclosed herein are exemplary in nature, and these specific instances are not intended to be limiting, as numerous variations are possible. For example, the above techniques can be applied to V-6, I-4, I-6, V-12, opposed 4, and other engine types. The subject matter of this invention 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.

[0152] The following claims specifically point to particular combinations and sub-combinations that are considered novel and non-obvious. These claims may refer to "a" element or "first" element or its equivalent. Such claims should be understood to include a combination of 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 amendments to the present claims or by the presentation of new claims in this or related applications. Such claims, whether their scope is broader, narrower or different from that of the original claims, are also considered to be included within the subject matter of this invention.

[0153] According to the present invention, a vehicle operation method is provided, the method comprising: in response to activation of an anti-lock braking system, adjusting the regenerative torque of the main shaft to the lower of the low-pass filtered main shaft adjustment torque of the right wheel and the low-pass filtered main shaft adjustment torque of the left wheel.

[0154] According to one embodiment, the invention is further characterized by the application of a friction brake in response to activation of the anti-lock braking system.

[0155] According to one embodiment, the anti-lock braking system is activated by activating a brake line pressure regulating valve.

[0156] According to one embodiment, the regenerative braking torque of the spindle is provided via a motor in the rear drive unit.

[0157] According to one embodiment, the invention is further characterized in that, when the anti-lock braking system is not activated, the regenerative torque of the spindle is adjusted in response to a requested braking torque provided by a human driver.

[0158] According to one embodiment, torque is supplied to the spindle via an engine and an electric motor.

[0159] According to one embodiment, the invention is further characterized by adjusting the friction brake of the spindle to a torque determined by subtracting the regenerative torque of the spindle from the braking adjustment torque of the spindle.

[0160] According to the present invention, a vehicle operation method is provided, the method comprising: adjusting the regenerative torque of the main shaft to the lower of the low-pass filtered main shaft adjustment torque of the right wheel and the low-pass filtered main shaft adjustment torque of the left wheel; and adjusting the regenerative torque of the secondary shaft to the lower of the low-pass filtered secondary shaft adjustment torque of the right wheel and the low-pass filtered secondary shaft adjustment torque of the left wheel.

[0161] According to one embodiment, the regenerative torque of the secondary shaft is further adjusted in response to the difference between the possible regenerative braking torque of the vehicle and the regenerative torque of the main shaft.

[0162] According to one embodiment, the invention is further characterized in that the friction brake of the secondary shaft is adjusted to a torque determined by subtracting the regenerative torque of the secondary shaft from the braking adjustment torque of the secondary shaft, wherein the cutoff frequency of the low-pass filtered main shaft adjustment torque is equal to the cutoff frequency of the low-pass filtered secondary shaft adjustment torque.

[0163] According to one embodiment, the cutoff frequency for adjusting torque via a low-pass filtered main shaft is different from the cutoff frequency for adjusting torque via a low-pass filtered secondary shaft.

[0164] According to one embodiment, the invention is further characterized by adjusting the regenerative torque of the main shaft and the regenerative torque of the secondary shaft in response to activation of the anti-lock braking system.

[0165] According to one embodiment, the anti-lock braking system is activated by activating a brake line pressure regulating valve.

[0166] According to one embodiment, the invention is further characterized in that, when the anti-lock braking system is not activated, the regenerative torque of the spindle is adjusted in response to a requested braking torque provided by a human driver.

[0167] According to the present invention, a vehicle system is provided, the vehicle system comprising: an anti-lock braking system including four friction brakes; a first motor; a second motor; and a controller, the controller including executable instructions stored in a non-transitory memory, the executable instructions causing the controller to filter wheel torque of a first axle via a first low-pass filter having a first cutoff frequency, and to filter wheel torque of a second axle via a second low-pass filter having a second cutoff frequency.

[0168] According to one embodiment, the invention is further characterized by an additional instruction for adjusting the regenerative torque of the spindle to a lower value than the low-pass filtered spindle adjustment torque of the right wheel and the low-pass filtered spindle adjustment torque of the left wheel.

[0169] According to one embodiment, the invention is further characterized by an additional instruction for adjusting the regenerative torque of the subshaft to a lower value than the low-pass filtered subshaft adjustment torque of the right wheel and the low-pass filtered subshaft adjustment torque of the left wheel.

[0170] According to one embodiment, the invention is further characterized by an additional command for applying at least one of four friction brakes in response to activating the anti-lock friction braking system.

[0171] According to one embodiment, the first cutoff frequency is lower than the second cutoff frequency.

[0172] According to one embodiment, the first cutoff frequency is based on both the inertia of the first motor and the smoothness of its power transmission system, while the second cutoff frequency is based on both the inertia of the second motor and the smoothness of its power transmission system, and wherein the first motor and

[0173] The second motor provides torque to the vehicle's drivetrain.

Claims

1. A vehicle operation method, the vehicle operation method comprising: In response to the activation of the anti-lock braking system, the regenerative torque of the main shaft is adjusted to the lower of the low-pass filtered main shaft adjustment torque of the right wheel and the low-pass filtered main shaft adjustment torque of the left wheel; The method further includes adjusting the regenerative torque of the subshaft to the lower of the low-pass filtered subshaft adjustment torque of the right wheel and the low-pass filtered subshaft adjustment torque of the left wheel.

2. The method of claim 1, further comprising applying a friction brake in response to activation of the anti-lock braking system.

3. The method according to claim 2, wherein the anti-lock braking system is activated by activating a brake line pressure regulating valve.

4. The method of claim 1, wherein the regenerative torque of the spindle is provided via a motor of the rear drive unit.

5. The method of claim 1, further comprising adjusting the regenerative torque of the spindle in response to a requested braking torque provided by a human driver when the anti-lock braking system is not activated.

6. The method of claim 1, wherein torque is provided to the spindle via an engine and a motor.

7. The method of claim 1, further comprising adjusting the friction brake of the spindle to a torque determined by subtracting the regenerative torque of the spindle from the braking adjustment torque of the spindle.

8. The method according to claim 1, wherein the method further comprises: Additionally, in response to the difference between the vehicle's possible regenerative braking torque and the regenerative torque of the main shaft, the regenerative torque of the secondary shaft is adjusted to the lower of the low-pass filtered secondary shaft adjustment torque of the right wheel and the low-pass filtered secondary shaft adjustment torque of the left wheel.

9. The method of claim 8, wherein the main shaft is a vehicle shaft that receives all drivetrain power when no wheel slippage is detected, and the secondary shaft is a vehicle shaft that can receive power from the drivetrain when positive drivetrain torque causes wheel slippage, but the secondary shaft does not receive positive power from the drivetrain when no wheel slippage is detected.

10. A vehicle system, the vehicle system comprising: An anti-lock braking system comprising four friction brakes; First motor; Second motor; as well as The controller includes executable instructions stored in a non-transitory memory, the executable instructions causing the controller to filter wheel torque of a first axle via a first low-pass filter having a first cutoff frequency, and to filter wheel torque of a second axle via a second low-pass filter having a second cutoff frequency. The vehicle system further includes additional instructions for adjusting the regenerative torque of the main axle to the lower of the low-pass filtered main axle adjustment torque of the right wheel and the low-pass filtered main axle adjustment torque of the left wheel. The vehicle system further includes additional instructions for adjusting the regenerative torque of the secondary axle to the lower of the low-pass filtered secondary axle adjustment torque of the right wheel and the low-pass filtered secondary axle adjustment torque of the left wheel.

11. The vehicle system according to claim 10, wherein, The main shaft is the axle of a vehicle that receives all power from the drivetrain when no wheel slippage is detected.

12. The vehicle system of claim 10, further comprising an additional command for applying at least one of the four friction brakes in response to activation of the anti-lock friction braking system.

13. The vehicle system of claim 10, wherein the first cutoff frequency is lower than the second cutoff frequency.

14. The vehicle system of claim 13, wherein the first cutoff frequency is based on the inertia of the first motor, wherein the second cutoff frequency is based on the inertia of the second motor, and wherein the first motor and the second motor provide torque to the vehicle drivetrain.

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