System and method for controlling a traction motor

Abstract

The present disclosure provides "systems and methods for controlling a traction motor". Systems and methods are presented for managing power consumption and operation of an electric machine configured to provide propulsion for a hybrid vehicle. In one example, a steering angle of the hybrid vehicle is a basis for managing power consumption and operation of the electric machine such that an amount of electrical power stored in an electrical power storage device can be conserved.

Description

Technical Field

[0001] This specification relates to methods and systems for providing smooth drivetrain operation during transmission downshifting and engine starting. Background Technology

[0002] Hybrid vehicles may include an internal combustion engine and an electric motor (e.g., a traction motor) for propelling the hybrid vehicle. The internal combustion engine can operate under medium to high driver demand and when the traction battery's state of charge (SOC) is low. The electric motor can assist the internal combustion engine under higher driver demand, and when the SOC is high, the electric motor may be the sole power source propelling the hybrid vehicle under low driver demand. However, the vehicle can operate under conditions that cause the SOC to drop and then remain low over time. During such conditions, the electric motor may not be able to assist the internal combustion engine under higher driver demand or propel the vehicle under light driver demand. This may reduce vehicle handling. Summary of the Invention

[0003] According to the present invention, a method for operating a vehicle includes: adjusting the output of a motor that propels the vehicle in response to the vehicle's steering angle via a controller.

[0004] In one aspect of the invention, the method includes filtering a steering angle signal via a first filter and a second filter, the first filter including a first filter factor, the second filter including a second filter factor, and a first time constant being smaller than a second time constant.

[0005] In one aspect of the invention, the method includes subtracting the output of the first filter from the output of the second filter to generate a first result.

[0006] In one aspect of the invention, the method includes selecting a motor gain value in response to the first result.

[0007] In one aspect of the invention, the method includes constraining the rate of increase of the first result to a first rate.

[0008] In one aspect of the invention, the method includes constraining the rate of decrease of the first result to a second rate.

[0009] In one aspect of the invention, adjusting the output of the motor propelling the vehicle in response to the vehicle's steering angle includes adjusting the output of the motor in response to the first result.

[0010] In one aspect of the invention, adjusting the output of the motor includes increasing the torque output of the motor in response to an increase in the steering angle.

[0011] According to the present invention, a system is provided comprising: an internal combustion engine; an electric motor; and a controller, the controller including executable instructions stored in a non-transitory memory, the executable instructions causing the controller to assist the torque output of the internal combustion engine via the electric motor in response to an indication that a vehicle including the internal combustion engine is leaving a turn on the road.

[0012] According to an embodiment, the instruction is based on a first result of the difference between the output of the first filter and the output of the second filter, and also includes additional executable instructions that cause the controller to input a steering angle to the first filter and the second filter.

[0013] According to an embodiment, the invention is further characterized in that it causes the controller to generate additional executable instructions for a gain value based on the first result.

[0014] According to an embodiment, the invention is further characterized by an additional executable instruction that causes the controller to multiply the maximum motor torque by the gain value to generate a second result.

[0015] According to an embodiment, the invention is further characterized by additional executable instructions that cause the controller to adjust the motor torque output in response to the second result.

[0016] According to an embodiment, the invention is further characterized by an additional instruction for constraining the rate of increase of the torque output of the motor in response to the time amount of the first result exceeding a threshold amount.

[0017] According to an embodiment, the invention is further characterized by an additional instruction for reducing the torque output of the motor in response to the first result being constant or decreasing.

[0018] According to the present invention, a method for operating a vehicle includes: adjusting the output of a motor propelling the vehicle via a controller in response to a rate-constrained motor torque gain value, the rate-constrained motor gain value being based on the vehicle's steering angle.

[0019] In one aspect of the invention, the rate-constrained motor torque gain value increases in response to the difference between the output of the first filter being greater than the output of the second filter within a predetermined time period.

[0020] In one aspect of the invention, the rate-constrained motor torque gain value decreases in response to the difference between the output of the first filter being less than or equal to the output of the second filter.

[0021] In one aspect of the invention, the output of the electric motor is adjusted while the internal combustion engine of the vehicle is operating.

[0022] In one aspect of the invention, the rate-constrained motor torque gain value is constrained to a value between zero and one. Attached Figure Description

[0023] The advantages described herein will be more fully understood when read, either alone or with reference to the accompanying drawings, by reading examples of embodiments referred to herein as specific implementations, in which:

[0024] Figure 1 This is a schematic diagram of the engine;

[0025] Figure 2 It includes Figure 1 A schematic diagram of the powertrain of a hybrid vehicle with an engine;

[0026] Figure 3 An example vehicle operating sequence is shown, in which the motor torque output can be adjusted according to the steering angle;

[0027] Figure 4 A block diagram of a method for adjusting the torque of a motor is shown; and

[0028] Figure 5A and Figure 5B This is a schematic diagram showing the vehicle's steering angle. Detailed Implementation

[0029] This specification relates to improving the handling of hybrid vehicles during sporty driving maneuvers. This improved handling may result from reduced motor operation and traction battery SOC, allowing the motor and battery SOC to be available for longer periods and when they can provide greater benefits. Hybrid vehicles may include... Figure 1 An internal combustion engine of the type shown. The engine can be, for example... Figure 2 The hybrid powertrain or part of the drivetrain shown. Figure 3 The text shows the data based on... Figure 4 The sequence of operations for the method. Figure 4 A block diagram of a method for operating a hybrid vehicle during sport driving maneuvers is shown. Figure 5A and Figure 5B The vehicle's steering angle is shown.

[0030] Hybrid vehicles can operate on roads or closed tracks, where they frequently stop and start moving depending on driving conditions. This frequent stopping and starting can tend to deplete the traction battery's charge. Over time, operating a hybrid vehicle under these conditions may deplete the traction battery, rendering the hybrid electric motor unable to propel the vehicle. While it may sometimes be desirable to propel the vehicle solely by the electric motor, there may be other times when propulsion via both the electric motor and the hybrid vehicle's internal combustion engine is considered a higher priority. Therefore, it may be desirable to provide a way to control the use of the electric motor and the traction battery, making it more likely that operation relying on both the electric motor and the traction battery can be performed during higher-priority conditions.

[0031] The inventors of this paper have recognized the above-mentioned problems and have developed a method for operating a vehicle, the method comprising: adjusting the output of a motor that propels the vehicle in response to the vehicle's steering angle via a controller.

[0032] By controlling the output of the electric motor that provides propulsion to the vehicle based on the vehicle's steering angle, energy savings can be achieved in situations where electricity can increase vehicle handling and extend the time during which electric assistance can be provided (e.g., where the motor increases the torque of the internal combustion engine to meet the driver's torque demands). Specifically, the steering angle can be manipulated to determine whether the vehicle is exiting a turn. At the exit of a road curve, improving vehicle handling by providing electric assistance to meet the driver's torque demands may be more beneficial than propelling the vehicle via the motor solely based on the driver's torque demands. For example, when high driver demands can be fully met at the exit of a road curve by both engine torque and motor torque, the driver can perceive increased handling compared to applying only the motor to meet lower driver demands. This allows for saving motor torque in situations where the driver desires increased vehicle responsiveness and eliminating motor torque in situations where the driver's torque demands can be met solely by the engine. Therefore, if the vehicle is operating on tracks or roads with relatively high turning frequencies, electric assistance can be made available for a longer period of time.

[0033] This specification offers several advantages. In particular, the method can improve the handling of hybrid vehicles. Furthermore, the method can be selectively activated according to specific vehicle operating modes, allowing for a closer fulfillment of driver expectations. Additionally, the method can improve the efficiency of torque transmission in the powertrain.

[0034] The above and other advantages and features of this specification will become readily apparent when understood alone or in conjunction with the accompanying drawings, based on the following detailed description.

[0035] It is understood that the above description of the invention is provided to present a series of concepts further described in the detailed embodiments in a simplified form. This is not intended to identify key features of the claimed subject matter, the scope of which is defined by the claims following the detailed description. Furthermore, the claimed subject matter is not limited to embodiments that address any shortcomings mentioned above or in any part of this disclosure.

[0036] refer to Figure 1 The internal combustion engine 10, comprising multiple cylinders, is controlled by an electronic controller 12 (e.g., an engine controller). Figure 1 One of the plurality of cylinders is shown. Engine 10 comprises a cylinder head 35 and a cylinder block 33, the cylinder head and cylinder block including a combustion chamber 30 and cylinder walls 32. A piston 36 is positioned therein and reciprocates via a connection to a crankshaft 40. A flywheel 97 and a ring gear 99 are coupled to the crankshaft 40. A flywheel starter 96 (e.g., a low-voltage (operating at less than 30 volts) motor) includes a pinion shaft 98 and a pinion 95. The pinion shaft 98 can selectively advance the pinion 95 to engage the ring gear 99. The flywheel starter 96 can be directly mounted to the front or rear of the engine. In some examples, the flywheel starter 96 can selectively supply torque to the crankshaft 40 via a connecting device. In one example, the flywheel starter 96 is in a basic state when not engaged with the engine crankshaft 40. The combustion chamber 30 is shown communicating with the intake manifold 44 and exhaust manifold 48 via corresponding intake valves 52 and exhaust valves 54. Each intake and exhaust valve can be operated by an intake cam 51 and an exhaust cam 53. The position of the intake cam 51 can be determined by an intake cam sensor 55. The position of the exhaust cam 53 can be determined by an exhaust cam sensor 57. The intake valve 52 can be selectively activated and deactivated by a valve actuation device 59. The exhaust valve 54 can be selectively activated and deactivated by a valve actuation device 58. The valve actuation devices 58 and 59 can be hydraulic and / or electromechanical devices.

[0037] Fuel injector 66 is shown positioned to inject fuel directly into cylinder 34, which is referred to as direct injection by those skilled in the art. Fuel injector 66 delivers liquid fuel in proportion to the pulse width from controller 12. Fuel is delivered to fuel injector 66 via a fuel system (not shown), which includes a fuel tank, a fuel pump, and a fuel rail (not shown). In one example, a high-pressure two-stage fuel system may be used to generate higher fuel pressures.

[0038] Additionally, the intake manifold 44 is shown communicating with the engine intake port 42. An optional electronic throttle valve 62 adjusts the position of the throttle plate 64 to control airflow from the engine intake port 42 to the intake manifold 44. In some examples, the throttle valve 62 and the throttle plate 64 may be positioned between the intake valve 52 and the intake manifold 44, such that the throttle valve 62 is an intake manifold throttle valve. An air filter 43 cleans the air entering the engine intake port 42.

[0039] Distributorless ignition system 88 provides an ignition spark to combustion chamber 30 via spark plug 92 in response to controller 12. Universal exhaust oxygen (UEGO) sensor 126 is shown coupled to exhaust manifold 48 upstream of catalytic converter 70. Alternatively, dual-state exhaust oxygen sensor 126 can be used instead of UEGO sensor 126.

[0040] In one example, the catalytic converter 70 may include multiple catalyst bricks. In another example, multiple emission control devices, each having multiple bricks, may be used. In one example, the catalytic converter 70 may be a three-way catalytic converter. The temperature of the catalytic converter 70 (e.g., the catalytic converter) may be monitored via a temperature sensor 72.

[0041] The controller 12 can receive input data from the human-machine interface 160 and provide output data to the human-machine interface. The human-machine interface 160 may be a touch screen display, a keyboard, or other known interface. The controller 12 can provide and display system status information via the human-machine interface 160. Human users can input requests for powertrain and passenger cabin climate control into the human-machine interface 160.

[0042] Controller 12 in Figure 1The controller 12 is shown as a conventional microcomputer, which includes a microprocessor unit 102, an input / output port 104, a read-only memory 106 (e.g., non-transitory memory), a random access memory 108, a keep-alive memory 110, and a conventional data bus. In addition to the signals previously discussed, the controller 12 is shown to also receive various signals from sensors coupled to the engine 10, including: engine coolant temperature (ECT) from a temperature sensor 112 coupled to a cooling sleeve 114; a position sensor 134 coupled to a driver demand pedal 130 for sensing the force applied by the foot 132; a position sensor 154 coupled to a brake caliper control pedal 150 for sensing the force applied by the foot 152; a measurement of engine manifold pressure (MAP) from a pressure sensor 122 coupled to an intake manifold 44; an engine position sensor from a position sensor 118 for sensing the position of the crankshaft 40; a measurement of the air mass entering the engine from a sensor 120; and a measurement of the throttle position from a sensor 68. Atmospheric pressure (sensor not shown) can also be sensed for processing by controller 12. In a preferred aspect of this specification, position sensor 118 generates a predetermined number of equally spaced pulses for each revolution of the crankshaft, thereby determining the engine speed (RPM).

[0043] During operation, each cylinder within engine 10 typically undergoes a four-stroke cycle: this cycle includes an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke. During the intake stroke, generally, the exhaust valve 54 is closed and the intake valve 52 is open. Air is introduced into combustion chamber 30 via intake manifold 44, and piston 36 moves to the bottom of the cylinder to increase the volume within combustion chamber 30. The position of piston 36 near the bottom of the cylinder and at the end of its stroke (e.g., when combustion chamber 30 is at its maximum volume) is generally referred to by those skilled in the art as bottom dead center (BDC).

[0044] During the compression stroke, both intake valve 52 and exhaust valve 54 are closed. Piston 36 moves toward the cylinder head to compress the air within combustion chamber 30. The point where piston 36 is located at the end of its stroke and closest to the cylinder head (e.g., when combustion chamber 30 is at its minimum volume) is generally referred to by those skilled in the art as top dead center (TDC). Fuel is introduced into the combustion chamber during what is hereinafter referred to as injection. The injected fuel is ignited by a known ignition device, such as spark plug 92, resulting in combustion.

[0045] During the expansion stroke, the expanding gas pushes piston 36 back to the BDC. Crankshaft 40 converts the piston movement into rotational torque on the rotating shaft. Finally, during the exhaust stroke, exhaust valve 54 opens to release the combusted air-fuel mixture into exhaust manifold 48, and piston returns to the TDC. It should be noted that the above is merely illustrative, and the opening and / or closing timing of the intake and exhaust valves can vary, such as to provide positive or negative valve overlap, delayed intake valve closing, or various other examples.

[0046] Figure 2 It is a block diagram of a vehicle 225 including a powertrain or transmission system 200. Figure 2 The power transmission system includes Figure 1 The engine 10 is shown in the diagram. The drivetrain 200 is shown as including a vehicle system controller 255, a controller 12, an electric motor controller 252, a transmission controller 254, an energy storage device controller 253, and a brake caliper controller 250. The controllers can communicate via a controller area network (CAN) 299. Additionally, the vehicle system controller 255 can communicate with a communication system 256 (e.g., a transceiver) to enable the vehicle 225 to communicate with a remote server (not shown) via a cellular network, satellite, vehicle-to-vehicle communication network, or other radio frequency communication system. Each of the controllers can provide information to the other controllers, such as power output constraints (e.g., power output of devices or components that are controlled to be exceeded), power input constraints (e.g., power input of devices or components that are controlled to be exceeded), power output of controlled devices, sensor and actuator data, and diagnostic information (e.g., information about a deteriorated transmission, information about a deteriorated engine, information about a deteriorated electric motor, and information about a deteriorated brake caliper). In addition, the vehicle system controller 255 can provide commands to the controller 12, the motor controller 252, the transmission controller 254, and the brake caliper controller 250 to fulfill driver input requests and other requests based on vehicle operating conditions.

[0047] For example, in response to a driver (human driver or autonomous driver) releasing the driver demand pedal and the vehicle speed, the vehicle system controller 255 can request desired wheel power or wheel power levels to provide a desired rate of vehicle speed reduction. The requested desired wheel power can be provided by the vehicle system controller 255 requesting first wheel brake caliper power from the motor controller 252 and second wheel brake caliper power from the controller 12, the first and second powers providing the desired drivetrain deceleration power at wheel 216. The vehicle system controller 255 can also request friction brake caliper power via brake caliper controller 250. Brake caliper power can be referred to as negative power because it decelerates the drivetrain and wheel rotation. Positive power can maintain or increase the speed of drivetrain and wheel rotation.

[0048] In other examples, the division of the control power transmission system device can be compared with... Figure 2 The different methods of division shown are illustrated. For example, a single controller can replace vehicle system controller 255, controller 12, motor controller 252, transmission controller 254, and brake caliper controller 250. Alternatively, vehicle system controller 255 and controller 12 can be a single unit, while motor controller 252, transmission controller 254, and brake caliper controller 250 are independent controllers.

[0049] In this example, the drivetrain 200 can be powered by the engine 10 and the electric motor 240. In other examples, the engine 10 can be omitted. Figure 1 The engine 10 is started by the engine starting system shown or via an electric motor 240, also known as an integrated starter / generator (ISG). Furthermore, the power of the engine 10 can be adjusted via power actuators 204, such as fuel injectors and throttle valves.

[0050] The drivetrain 200 is shown to include an energy storage device 262. The energy storage device 262 can output a higher voltage (e.g., 48 volts) than the energy storage device 263 (e.g., 12 volts). A DC / DC converter 245 allows the exchange of electrical energy between a high-voltage bus 291 and a low-voltage bus 292. The high-voltage bus 291 is electrically connected to the higher-voltage energy storage device 262. The low-voltage bus 292 is electrically connected to the lower-voltage energy storage device 263 and a sensor / actuator / accessory 279. The sensor / actuator / accessory 279 may include, but is not limited to, windshield and rear windshield resistance heaters, a vacuum pump, a climate control fan, and lights. An inverter 247 converts DC power to AC power and vice versa, enabling power transfer between the motor 240 and the energy storage device 262.

[0051] Engine output power can be transmitted via dual-mass flywheel 215 to the input or first side of drivetrain release clutch 235. Drivetrain release clutch 236 can be hydraulically actuated via fluid (e.g., oil) pressurized by pump 283. The position of valve 282 (e.g., line pressure control valve) can be adjusted to control the pressure (e.g., line pressure) of fluid that can be supplied to drivetrain release clutch pressure control valve 281. The position of valve 281 can be adjusted to control the pressure of fluid supplied to drivetrain release clutch 235. The downstream or second side 234 of drivetrain release clutch 236 is shown as mechanically coupled to motor input shaft 237.

[0052] Motor 240 can be operated to provide power to drivetrain 200, or in regenerative mode to convert drivetrain power into electrical energy for storage in energy storage device 262. Motor 240 is electrically connected to energy storage device 262. Motor 240 has a ratio of Figure 1 The flywheel starter 96 shown has a higher output power capacity. Furthermore, the motor 240 directly drives the drivetrain 200 or is directly driven by the drivetrain 200. There are no gears or chains connecting the motor 240 to the drivetrain 200. Instead, the motor 240 rotates at the same rate as the drivetrain 200. The energy storage device 262 (e.g., a high-voltage battery or power source, which may be referred to as a traction battery) may be a battery, capacitor, or inductor. The downstream side of the motor 240 is mechanically coupled to the torque converter pump wheel 285 of the torque converter 206 via shaft 241. The upstream side of the motor 240 is mechanically coupled to the disengagement clutch 236. The motor 240 can provide positive or negative power to the drivetrain 200 by acting as a motor or generator as instructed by the motor controller 252.

[0053] Torque converter 206 includes a torque converter turbine 286 to output power to an input shaft 270. The input shaft 270 mechanically connects torque converter 206 to an automatic transmission 208. Torque converter 206 also includes a torque converter lock-up clutch 212 (TCC). When the TCC is locked, power is transmitted directly from the torque converter impeller 285 to the torque converter turbine 286. The TCC is electrically operated via a transmission controller 254. Alternatively, the TCC may be hydraulically locked. In one example, the torque converter may be referred to as a component of the transmission.

[0054] When the torque converter lock-up clutch 212 is fully disengaged, the torque converter 206 transmits engine power to the automatic transmission 208 via fluid transfer between the torque converter turbine 286 and the torque converter pump impeller 285, thereby doubling the torque. In contrast, when the torque converter lock-up clutch 212 is fully engaged, engine output power is transmitted directly to the input shaft 270 of the automatic transmission 208 via the torque converter clutch. Alternatively, the torque converter lock-up clutch 212 can be partially engaged, thereby supporting adjustment of the amount of power transmitted directly to the transmission. The transmission controller 254 can be configured to adjust the amount of power transmitted by the torque converter lock-up clutch 212 in response to various engine operating conditions or based on driver-based engine operation requests.

[0055] The torque converter 206 also includes a pump 283 that pressurizes transmission fluid 295 to operate the drivetrain disengagement clutch 236, the forward clutch 210, and the gear clutch 211. The pump 283 is driven via a torque converter pump impeller 285, which rotates at the same speed as the motor 240.

[0056] Automatic transmission 208 includes a gear clutch 211 (e.g., gears 1 to 10) and a forward clutch 210 actuated via transmission fluid 295. Automatic transmission 208 is a fixed gear ratio transmission. Alternatively, automatic transmission 208 may be a continuously variable transmission (CVT) with the ability to simulate both a fixed gear ratio transmission and a fixed gear ratio. Gear clutch 211 and forward clutch 210 can be selectively engaged to change the ratio of the actual total revolutions of the input shaft 270 to the actual total revolutions of the wheels 216. Gear clutch 211 can be engaged or disengaged by adjusting the fluid supplied to the clutches via shift control solenoid valve 209. Power output from automatic transmission 208 can also be relayed to wheels 216 via output shaft 260 to propel the vehicle. Specifically, automatic transmission 208 may transmit input drive power at input shaft 270 in response to vehicle driving conditions before transmitting output drive power to wheels 216. When automatic transmission 208 is in park, parking pawl 296 can be engaged to prevent movement of output shaft 260. The transmission controller 254 selectively engages or disengages the TCC 212, gear clutch 211, and forward clutch 210. The transmission controller also selectively disengages or deactivates the TCC 212, gear clutch 211, and forward clutch 210.

[0057] Friction can be applied to wheel 216 by engaging friction brake caliper 218. In one example, friction brake caliper 218 of wheel 216 can engage in response to a human driver pressing their foot on brake caliper control pedal (not shown) and / or in response to a command within brake caliper controller 250. Furthermore, brake caliper controller 250 can engage friction brake caliper 218 in response to information and / or requests from vehicle system controller 255. Similarly, friction on wheel 216 can be reduced by disengaging friction brake caliper 218 in response to a human driver releasing their foot from brake caliper control pedal, brake caliper controller command and / or vehicle system controller command and / or information. For example, as part of an automated vehicle stopping procedure, vehicle brake calipers can apply friction to wheel 216 via brake caliper controller 250. The deceleration torque can be determined based on the position of brake caliper control pedal.

[0058] In response to a request to increase the speed of vehicle 225, the vehicle system controller 255 may obtain a driver-demanded power or power request from the driver demand pedal or other device. Vehicle system controller 255 then allocates a portion of the requested driver-demanded power to the engine and the remainder to the electric motor. Vehicle system controller 255 requests engine power from controller 12 and electric motor power from electric motor controller 252. If the electric motor power plus the engine power is less than a transmission input power threshold (e.g., a threshold that must not be exceeded), power is delivered to torque converter 206, which then relays at least a portion of the requested power to transmission input shaft 270. Transmission controller 254 may selectively lock the torque converter lock-up clutch 212 and engage a gear via gear clutch 211 in response to a shift schedule and TCC lock-up schedule that can be based on input shaft power and vehicle speed. In some situations, when it may be desirable to charge the energy storage device 262, charging power (e.g., negative electric motor power) may be requested when a non-zero driver-demanded power is present. Vehicle system controller 255 may request increased engine power to overcome the charging power and meet the driver-demanded power.

[0059] In response to a request to reduce the speed of vehicle 225 and provide regenerative vehicle deceleration, the vehicle system controller can provide negative desired wheel power (e.g., desired or requested powertrain wheel power) based on vehicle speed and brake caliper control pedal position. The vehicle system controller 255 then allocates a portion of the negative desired wheel power to motor 240 and engine 10. The vehicle system controller can also allocate a portion of the requested deceleration power to friction brake caliper 218 (e.g., desired friction brake caliper wheel power). Furthermore, the vehicle system controller can notify transmission controller 254 that the vehicle is in regenerative deceleration mode, causing transmission controller 254 to shift gears based on a specific shift schedule to improve regenerative efficiency. Engine 10 and motor 240 can supply negative power to transmission input shaft 270, but the negative power provided by motor 240 and engine 10 can be constrained by transmission controller 254, which outputs a transmission input shaft negative power threshold (e.g., a threshold that must not be exceeded). Furthermore, the vehicle system controller 255 or the motor controller 252 can constrain the negative power of the motor 240 based on the operating conditions of the energy storage device 262 (e.g., constrained to less than a threshold negative power). Any portion of the desired negative wheel power that may not be provided by the motor 240 due to transmission or motor thresholds can be allocated to the engine 10 and / or the friction brake caliper 218, such that the desired wheel power is provided through a combination of the negative power (e.g., absorbed power) of the friction brake caliper 218, the engine 10, and the motor 240.

[0060] Therefore, power control of various powertrain components can be supervised by vehicle system controller 255, which provides partial power control of engine 10, automatic transmission 208, motor 240 and friction brake caliper 218 via controller 12, motor controller 252, transmission controller 254 and brake caliper controller 250.

[0061] As an example, engine power output can be controlled by controlling the throttle opening and / or valve timing, valve lift, and boost adjustment spark timing, fuel pulse width, fuel pulse timing, and / or air charging combination of a turbocharged or supercharged engine. In the case of a diesel engine, controller 12 can control engine power output by controlling a combination of fuel pulse width, fuel pulse timing, and air charging. Engine deceleration power or negative engine power can be provided by rotating the engine when the power generated is insufficient to rotate it. Therefore, the engine can generate deceleration power by operating at low power while burning fuel, where one or more cylinders are deactivated (e.g., no fuel is burned), or where all cylinders are deactivated and the engine is rotated simultaneously. The amount of engine deceleration power can be adjusted by adjusting the engine valve timing. Engine valve timing can be adjusted to increase or decrease engine compression work. Furthermore, engine valve timing can be adjusted to increase or decrease engine expansion work. In all cases, engine control can be performed cylinder-by-cylinder to control engine power output.

[0062] The motor controller 252 can control the power output and electrical energy generation from the motor 240 by adjusting the current flowing into and out of the rotor and / or armature windings of the motor, as is known in the art.

[0063] The transmission controller 254 receives the transmission input shaft position via position sensor 271. The transmission controller 254 can convert the transmission input shaft position into an input shaft speed by differentiating the signal from position sensor 271 or by counting a number of known angular distance pulses within a predetermined time interval. The transmission controller 254 can receive the transmission output shaft torque from torque sensor 272. Alternatively, sensor 272 can be a position sensor or a torque and position sensor. If sensor 272 is a position sensor, the transmission controller 254 can count shaft position pulses within a predetermined time interval to determine the transmission output shaft speed. The transmission controller 254 can also differentiate the transmission output shaft speed to determine the rate of change of the transmission output shaft speed. The transmission controller 254, controller 12, and vehicle system controller 255 can also receive additional transmission information from sensor 277, which may include, but is not limited to, a pump output line pressure sensor, a transmission hydraulic sensor (e.g., a gear clutch fluid pressure sensor), a transmission fluid temperature sensor, a motor temperature sensor, a gear selector position sensor, and an ambient temperature sensor. The transmission controller 254 can also receive requested gear input from the gear selector 290 (e.g., a human / machine interface device). The gear selector 290 may include positions for gears 1 to N (where N is the number of higher gears), D (drive), R (reverse), and P (park), as indicated at 293.

[0064] The brake caliper controller 250 receives wheel speed information via wheel speed sensor 221 and receives deceleration requests from vehicle system controller 255. The brake caliper controller 250 can also receive information directly or via CAN 299 from... Figure 1 The position sensor 154 shown receives brake caliper pedal position information. The brake caliper controller 250 can provide deceleration in response to wheel power commands from the vehicle system controller 255. The brake caliper controller 250 can also provide anti-lock braking and vehicle stability to improve vehicle deceleration and stability. To this end, the brake caliper controller 250 can provide the vehicle system controller 255 with wheel power thresholds (e.g., a threshold of negative wheel power that must not be exceeded) such that negative motor power does not cause the wheel power threshold to be exceeded. For example, if the brake caliper controller 250 issues a negative wheel power threshold of 50 Nm, the motor power is adjusted to provide less than 50 Nm (e.g., 49 Nm) of negative power at the wheel, taking into account transmission gearing.

[0065] Vehicle 225 may also include a steering wheel 213. A human driver can rotate the steering wheel 213 to generate a steering angle of the vehicle's front wheels (not shown), thereby causing the vehicle to travel straight or turn. A steering angle sensor 214 may be coupled to the steering wheel 213 or a steering linkage (not shown) to determine the vehicle's steering angle. The steering angle sensor 214 can generate a steering angle signal 219 indicating the steering angle and can be input to one or more controllers (e.g., vehicle system controller 255 or motor controller 252). When the vehicle is traveling in a straight line and the steering wheel is in its centered position, the steering angle determined by the steering wheel sensor can be zero. Alternatively, the vehicle's steering angle can be determined via a sensor that monitors the angle of the vehicle's steering pinion or a sensor that monitors the caster angle of the vehicle's wheels, such as... Figure 5A and Figure 5B As shown.

[0066] therefore, Figure 1 and Figure 2 The system provides a system comprising: an internal combustion engine; an electric motor; and a controller, the controller including executable instructions stored in a non-transitory memory, the executable instructions causing the controller to assist the torque output of the internal combustion engine via the electric motor in response to an indication that a vehicle including the internal combustion engine is leaving a turn. In a first example, the system includes: wherein the indication is a first result based on the difference between the output of a first filter and the output of a second filter, and further includes additional executable instructions causing the controller to input a steering angle to the first filter and the second filter. In a second example that may include the first example, the system further includes additional executable instructions causing the controller to generate a gain value based on the first result. In a third example that may include one or both of the first and second examples, the system further includes additional executable instructions causing the controller to multiply the maximum motor torque by the gain value to generate a second result. In a fourth example that may include one or more of the first to third examples, the system further includes additional executable instructions causing the controller to adjust the torque output of the electric motor in response to the second result. In a fifth example, which may include one or more of the first to fourth examples, the system further includes additional executable instructions for constraining the rate of increase of the torque output of the motor in response to the first result exceeding a threshold amount. In a sixth example, which may include one or more of the first to fifth examples, the system further includes additional instructions for reducing the torque output of the motor in response to the first result being constant or decreasing.

[0067] Now for reference Figure 3 This shows a predictive vehicle operation sequence. Figure 3 The operation sequence can be via Figure 1 and Figure 2 The system and Figure 4 The method is provided collaboratively. The vertical lines at times t0 to t3 represent the times of interest during the operation sequence. The graph is time-aligned, and the vehicles (not shown) in the vehicle operation sequence are traveling on the road.

[0068] from Figure 3 The first curve at the top is a graph of the unfiltered vehicle steering angle relative to time. The vertical axis represents the unfiltered vehicle steering angle in degrees. The horizontal axis represents time, and time increases from the left to the right of the curve. Trace 302 represents the unfiltered vehicle steering angle.

[0069] from Figure 3 The second graph from the top is a graph of the fast-filtered vehicle steering angle versus time. The vertical axis represents the fast-filtered vehicle steering angle in degrees. The horizontal axis represents time, and time increases from the left to the right of the graph. Trace 304 represents the fast-filtered vehicle steering angle. In one example, the steering angle can be filtered via a low-pass digital filter of the form Y(k) = α1U(k) + (1-α1)Y(k-1), where k is the number of signal samples, Y is the filter output value, U is the filter input value, and α1 is the fast filtering factor. A low-pass filter can be described as fast filtering the vehicle steering angle signal when the cutoff frequency of the low-pass filter (e.g., the frequency at which the steering angle signal attenuates by -3 dB) is greater than a threshold frequency (e.g., 20 Hz). The fast filtering factor α1 is expressed by the following equation: α1 = 1 - Related to the cutoff frequency, where It is the cutoff frequency of the low-pass filter. It is the Euler number, and T s This is the sampling time of the low-pass filter. The low-pass filter can be implemented via a controller that receives the unfiltered steering angle signal.

[0070] from Figure 3The third curve from the top is a graph of the vehicle steering angle as a function of time after slow filtering. The vertical axis represents the vehicle steering angle after fast filtering, in degrees. The horizontal axis represents time, increasing from the left to the right of the curve. Trace 306 represents the vehicle steering angle after slow filtering. In one example, the vehicle steering angle can be filtered via a low-pass digital filter of the form Y(k) = α²U(k) + (1-α²)Y(k-1), where k is the number of signal samples, Y is the filter output value, U is the filter input value, and α² is the slow filtering factor. A low-pass filter can be described as slow filtering of the vehicle steering angle signal when the cutoff frequency of the low-pass filter (e.g., the frequency at which the steering angle signal attenuates by -3 dB) is less than a threshold frequency (e.g., 10 Hz).

[0071] from Figure 3 The fourth curve from the top is a graph of the torque gain of the traction motor or motor (e.g., a real number in the range of 0 to 1) versus time. The vertical axis represents the traction motor or motor gain. The horizontal axis represents time, and time increases from the left to the right of the curve. Trace 308 represents the traction motor or motor gain.

[0072] At time t0, the unfiltered vehicle steering angle is zero (e.g., the front wheels of the vehicle are facing forward, causing the vehicle to travel in a straight line), the fast-filtered vehicle steering angle is zero, the slow-filtered vehicle steering angle is zero, and the traction motor gain is approximately 0.2. The traction motor gain of 0.2 can be multiplied by the maximum traction motor torque value to determine the amount of torque that the traction motor can provide to the drivetrain.

[0073] At time t1, the steering angle of the unfiltered vehicle begins to increase. The steering angle of the fast-filtered vehicle begins to increase shortly after time t1. The steering angle of the slow-filtered vehicle also begins to increase after time t1, but at a lower rate compared to the fast-filtered vehicle. The traction motor gain remains at approximately 0.2.

[0074] Between time t1 and time t2, the unfiltered vehicle steering angle reaches a threshold angle and remains at that angle. The fast-filtered vehicle steering angle has reached the same threshold angle as the unfiltered vehicle steering angle and remains at that angle. Similarly, the slow-filtered vehicle steering angle has also reached the same threshold angle as the unfiltered vehicle steering angle and remains at that angle. The traction motor gain remains at approximately 0.2.

[0075] At time t2, the unfiltered vehicle steering angle begins to decrease. The fast-filtered vehicle steering angle begins to decrease shortly after time t2. The slow-filtered vehicle steering angle also begins to decrease after time t2, but at a lower rate of increase compared to the fast-filtered steering angle. The traction motor gain begins to increase in response to the angular difference between the slow-filtered and fast-filtered vehicle steering angles. Therefore, the motor gain now begins to increase based on the vehicle steering angle.

[0076] At time t3, the unfiltered vehicle steering angle has returned to zero degrees, and both the fast-filtered and slow-filtered vehicle steering angles continue to decrease towards zero. The traction motor gain continues to increase with the difference between the slow-filtered and fast-filtered vehicle steering angles.

[0077] Between time t3 and time t4, the traction motor gain reaches its highest level during the sequence and then begins to decline. The fast-filtered and slow-filtered vehicle steering angles continue to decrease. The unfiltered vehicle steering angle remains zero.

[0078] At time t4, the vehicle steering angle after fast filtering reaches zero, and the vehicle steering angle after slow filtering continues to decrease. The traction motor gain also continues to decrease, and since the vehicle steering angle after fast filtering is zero, the traction motor gain trajectory is similar to that after slow filtering. The unfiltered vehicle steering angle remains zero.

[0079] At time t5, the vehicle steering angle after slow filtering reaches zero, and the traction motor gain reaches the level it exhibited before time t1. Therefore, the motor gain does not increase or decrease based on the vehicle steering angle.

[0080] In this way, the traction motor gain and torque can be adjusted based on the vehicle's steering angle. When the vehicle begins to enter the turn as shown at time t1, the traction motor gain and torque are not adjusted based on the unfiltered vehicle steering angle or the slowly and quickly filtered vehicle steering angles. Conversely, when the vehicle begins to leave the turn at time t2, the traction motor gain and torque can be adjusted based on the unfiltered vehicle steering angle, the slowly filtered vehicle steering angle, and the quickly filtered vehicle steering angle. This allows for battery conservation in times and conditions where improving vehicle handling by enhancing vehicle performance at the exit of a turn can be highly beneficial. This approach may be desirable when the vehicle is operating in Sport mode or on roads that include a relatively large number of turns within a relatively short travel distance.

[0081] Now for reference Figure 4A block diagram 400 is shown for a method of operating a hybrid vehicle. Figure 4 The method can be implemented at least partially as stored in Figure 1 and Figure 2 The executable instructions in the controller memory of the system. Furthermore, Figure 4 The methods can include actions taken in the physical world to transform Figure 1 and Figure 2 The system's operational status. Additionally, Figure 4 The method can provide Figure 3 At least a portion of the operational sequence shown. Method 400 can be performed when the hybrid vehicle is operating in a sport mode (e.g., a mode in which vehicle performance may be higher than that of the base vehicle) and performing sport driving maneuvers (e.g., performing a greater number of turns in a relatively short period of time, such as making three or more vehicle turns in less than a minute, and the driver-demand torque at the exit of the turn exceeds a threshold driver-demand torque).

[0082] At box 402, an unfiltered or raw vehicle steering angle signal is received from sensor 214. Box 402 passes the positive angle from the unfiltered vehicle steering angle signal to boxes 404 and 406. Box 402 changes the sign of the negative steering angle received from sensor 214 while retaining its magnitude. Therefore, box 402 outputs only the positive steering angle with a magnitude that has not been modified from the raw steering angle value. This allows the traction motor gain to respond to both right and left angles in a similar manner.

[0083] At block 404, the raw or unfiltered steering angle is received and processed via a low-pass filter based on a fast filtering factor α1. The low-pass filter can have the form Y(k) = α1U(k) + (1-α1)Y(k-1) as previously described. Block 404 outputs the low-pass filtered vehicle steering angle (which can be referred to as the fast-filtered vehicle steering angle) to block 408 via the filter output.

[0084] At block 406, the raw or unfiltered steering angle is received and processed via a low-pass filter based on a slow filtering factor α2. The low-pass filter can have the form Y(k) = α2U(k) + (1-α2)Y(k-1) as previously described. Block 404 outputs the low-pass filtered vehicle steering angle (which can be referred to as the slow-filtered vehicle steering angle) to block 408 via the filter output.

[0085] At box 408, method 400 subtracts the fast-filtered vehicle steering angle output from box 404 from the slow-filtered vehicle steering angle output from box 404. The result of the subtraction is input to boxes 410, 412, and 414. A negative value output from box 408 indicates that the vehicle is entering a turn. A positive value output from box 408 indicates that the vehicle is leaving a turn.

[0086] At box 410, the output of box 408 (the difference between the low-pass filter output and the high-pass filter output) is used to reference or index a table or function that outputs the traction motor or motor gain values. The traction motor gain or motor gain increases as the output of box 408 increases. Box 410 outputs the traction motor gain or motor gain value to box 430.

[0087] At box 412, it is determined whether the output of box 408 is greater than the predetermined threshold used to set the timer. If yes, box 412 outputs a value of one or a true logic state to box 416. If no, box 412 outputs a value of zero or a false logic state to box 416.

[0088] At box 414, it is determined whether the output of box 408 is less than or equal to a predetermined threshold used to reset the timer. If yes, box 414 outputs a value of one or a true logic state to box 416. If no, box 412 outputs a value of zero or a false logic state to box 416.

[0089] At box 416, if the output of box 412 is true or one and the output of box 414 is false or zero, the timer is activated and counting begins. If the output of box 414 is true or one, the timer is reset to zero. Box 416 outputs the count value or time value to box 418.

[0090] At box 418, determine if the output (time value) of box 416 is greater than the predetermined verification time. If yes, box 418 outputs a true indicator. If no, box 418 outputs a false indicator. Input the output of box 418 into box 420.

[0091] At box 420, the output of box 418 is applied to determine whether to output the maximum increment value or the value of zero. Specifically, if the output of box 418 is true, then box 420 acts as a switch and outputs the maximum increment value. If the output of box 418 is false, then box 420 outputs the value of zero. The output of box 420 is then fed into box 430.

[0092] At box 430, a constraint on the rate of change of the traction motor gain or motor gain can be applied. Box 430 can be operated to constrain the rate of change of the traction gain, which can be determined as: Rate_Gain = u(i) - y(i-1) / t(i) - t(i-1), where u is the traction motor gain or motor gain output from box 410, y is the output of box 430, i is the current number of data samples, and t is time. If the value of Rate_Gain exceeds a threshold R, the output of box 430 is... , where y is the output of box 430, i is the current number of data samples, t is time, and R is the threshold rate of the traction motor gain. If the value of Rate_Gain is less than the threshold F, then the output of box 430 is Let y be the output of box 430, i be the current number of data samples, t be time, and F be the threshold rate of the traction motor gain. y(i) = u(i) if the value of Rate_Gain is not greater than R or if the value of Rate_Gain is not less than F. The output of box 430 can be described as a rate-constrained traction motor gain or a rate-constrained motor gain. In one example, the output of box 430 can be multiplied by the maximum traction motor torque or the maximum motor torque and stored as the variable Mtrgen2llw in the controller memory. If the torque requested by the vehicle's human driver is less than max_eng_tq (maximum engine torque) + MtrGEN2Alw, the engine and motor provide the requested torque. However, if the torque requested by the vehicle's human driver is greater than max_eng_tq + MtrGen2Allw torque, the torque delivered via the engine and motor is constrained to max_eng_tq + MtrGen2Allw torque.

[0093] In this way, Figure 4 This method allows for adjusting the motor torque gain or traction motor torque gain in response to the vehicle's steering angle. Specifically, Figure 4 The method adjusts the motor torque or traction motor torque based on the difference between the vehicle steering angle after slow filtering and the vehicle steering angle after fast filtering. This allows the controller to distinguish between vehicles entering and leaving a turn, enabling the controller to adjust the traction motor torque gain or motor torque gain when adjustments can improve vehicle handling in the desired manner.

[0094] Therefore, method 400 provides a method for operating a vehicle, the method comprising: adjusting the output of a motor propelling the vehicle in response to a steering angle of the vehicle via a controller. In a first example, the method further comprises filtering a steering angle signal via a first filter and a second filter, the first filter including a first filter factor, the second filter including a second filter factor, and a first time constant being less than a second time constant. In a second example that may include the first example, the method further comprises subtracting the output of the first filter from the output of the second filter to generate a first result. In a third example that may include one or both of the first and second examples, the method further comprises selecting a motor gain value in response to the first result. In a fourth example that may include one or more of the first to third examples, the method further comprises constraining the rate of increase of the first result to a first rate. In a fifth example that may include one or more of the first to fourth examples, constraining the rate of decrease of the first result to a second rate. In a sixth example that may include one or more of the first to fifth examples, the method comprises: wherein adjusting the output of the motor propelling the vehicle in response to the steering angle of the vehicle includes adjusting the output of the motor in response to the first result. In a seventh example, which may include one or more of the first to sixth examples, the method includes: wherein adjusting the output of the motor includes increasing the torque output of the motor in response to an increase in the steering angle.

[0095] Method 400 also provides a method for operating a vehicle, the method comprising: adjusting the output of a motor propelling the vehicle via a controller in response to a rate-constrained motor torque gain value, the rate-constrained motor gain value being based on the vehicle's steering angle. In a first example, the method comprises: wherein the rate-constrained motor torque gain value increases in response to a difference between the output of a first filter and the output of a second filter over a predetermined time period. In a second example, which may include the first example, the method comprises: wherein the rate-constrained motor torque gain value decreases in response to a difference between the output of the first filter and the output of the second filter. In a third example, which may include one or both of the first and second examples, the method comprises: wherein adjusting the output of the motor is performed while the vehicle's internal combustion engine is operating. In a fourth example, which may include one or more of the first to third examples, the method comprises: wherein the rate-constrained motor torque gain is constrained to a value between zero and one.

[0096] Now for reference Figure 5AA schematic diagram of a vehicle 225 operating at a zero-degree steering angle is shown. The longitudinal axis 500 of the vehicle 225 is shown to bisect the vehicle 225 along its length. Each of the wheels 550a and 550b includes a longitudinal axis parallel to the vehicle's longitudinal axis 500. As wheels 550a and 550b rotate, their longitudinal axes 502 rotate. In this example, the angle between the wheel's longitudinal axis 502 and the vehicle's longitudinal axis 500 is the steering angle. In this example, the steering angle is zero because the wheel's longitudinal axis 502 is parallel to the vehicle's longitudinal axis 500. When the wheel's longitudinal axis 502 is parallel to the vehicle's longitudinal axis 500, the vehicle 225 travels along a straight path.

[0097] Now for reference Figure 5B A schematic diagram of vehicle 225 operating at a steering angle of θ degrees is shown. (As...) Figure 5A As shown, the longitudinal axis 500 of vehicle 225 bisects the vehicle 225 along its length. The longitudinal axis 502 of each of wheels 550a and 550b is not parallel to the longitudinal axis 500 of the vehicle. Instead, the wheel longitudinal axis 502 is oriented at an angle θ to the longitudinal axis 500 of the vehicle. The angle θ of each of wheels 550a and 550b is shown at 505. In this example, the angle θ between the wheel longitudinal axis 502 and the longitudinal axis 500 of the vehicle is the steering angle. The position where the wheel axis 502 is parallel to the longitudinal axis 500 of the vehicle, and the angle between the wheel axis 502 and the wheel axis 502 when wheels 550a and 550b rotate, can also be called the steering angle.

[0098] It should be noted that the example control and estimation routines included herein can be used with various engine and / or vehicle system configurations. Furthermore, the methods described herein can be combinations of actions taken by a controller in the physical world and instructions within the controller. At least portions of 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. 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.). Therefore, the various actions, operations, and / or functions shown may be performed in the order shown, in parallel, or in some cases omitted. Similarly, the processing order is not necessarily necessary to achieve the features and advantages of the example embodiments described herein, but is provided for ease of illustration and description. One or more of the shown actions, operations, and / or functions can be repeatedly performed depending on the specific strategy used. Furthermore, the actions, operations, and / or functions can be graphically represented by code programmed into a non-transitory memory of a computer-readable storage medium in the engine control system, wherein the described actions are implemented by executing instructions in conjunction with an electronic controller in a system comprising various engine hardware components.

[0099] This specification concludes here. Many variations and modifications will arise in those skilled in the art upon reading this specification without departing from its spirit and scope. For example, I3, I4, I5, V6, V8, V10, and V12 engines operating with natural gas, gasoline, diesel, or alternative fuels may benefit from this specification.

Claims

1. A method for operating a vehicle, the method comprising: The output of the motor that propels the vehicle is adjusted via the controller in response to the vehicle's steering angle.

2. The method of claim 1, further comprising filtering the steering angle signal via a first filter and a second filter, wherein the first filter includes a first filter factor, the second filter includes a second filter factor, and the first time constant is less than the second time constant.

3. The method of claim 2, further comprising subtracting the output of the first filter from the output of the second filter to generate a first result.

4. The method of claim 3, further comprising selecting a motor gain value in response to the first result.

5. The method of claim 4, further comprising constraining the rate of increase of the first result to a first rate.

6. The method of claim 4, further comprising constraining the rate of decrease of the first result to a second rate.

7. The method of claim 6, wherein adjusting the output of the motor propelling the vehicle in response to the steering angle of the vehicle includes adjusting the output of the motor in response to the first result.

8. The method of claim 7, wherein adjusting the output of the motor includes increasing the torque output of the motor in response to an increase in the steering angle.

9. A system comprising: Internal combustion engine; Electric motor; as well as The controller includes executable instructions stored in a non-transitory memory, the executable instructions causing the controller to assist the torque output of the internal combustion engine via the electric motor in response to an indication that the vehicle including the internal combustion engine is leaving a turn on the road.

10. The system of claim 9, wherein the indication is based on a first result of the difference between the output of the first filter and the output of the second filter, and the system further includes additional executable instructions that cause the controller to input a steering angle to the first filter and the second filter.

11. The system of claim 10, further comprising additional executable instructions that cause the controller to generate a gain value based on the first result.

12. The system of claim 11, further comprising additional executable instructions that cause the controller to multiply the maximum motor torque by the gain value to generate a second result.

13. The system of claim 12, further comprising additional executable instructions that cause the controller to adjust the motor torque output in response to the second result.

14. The system of claim 13, further comprising additional instructions for constraining the rate of increase of the torque output of the motor in response to the time amount of the first result exceeding a threshold amount.

15. The system of claim 14, further comprising additional instructions for reducing the torque output of the motor in response to the first result being constant or decreasing.

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