Motor clutch actuator control system and method

Abstract

The invention relates to motor clutch actuator control systems and methods. A clutch control system for a vehicle includes a reset module configured to selectively initiate a reset operation of a clutch actuator of a clutch that engages an electric propulsion motor to a gear set and unengages the electric propulsion motor from the gear set; a target position module configured to perform a reset operation by setting a target position of the clutch actuator to follow a predetermined position profile of the reset operation, the reset operation including (a) opening an orifice between the hydraulic fluid reservoir and a pressure chamber of the clutch actuator (b) closing the orifice after opening; and a clutch control module configured to actuate a clutch actuator based on the target position, thereby performing a reset operation.

Description

TECHNICAL FIELD

[0001] The information provided in this section is intended for the purpose of presenting the context of the disclosure. The work of the inventors in the field to the extent described in this section and various aspects of the description that can not have been qualifying prior art at the time of submission are neither expressly nor impliedly admitted to be prior art against the disclosure.

[0002] The present disclosure relates to an electric motor torque transmission system, and more particularly to systems and methods for actuating a clutched clutch. BACKGROUND

[0003] Vehicles with engines include a battery for cranking the engine and supporting accessory loads. Electric vehicles (EVs), such as battery electric vehicles (BEVs), hybrid vehicles, and / or fuel cell vehicles, include one or more electric machines and a battery system including one or more battery cells, battery modules, and / or battery packs to provide propulsion power. A power control system is used to control power to / from the battery system during charging, propulsion, and / or regeneration.

[0004] Lithium-ion batteries (LIBs) have high power density and are used in EV and non-EV applications. LIBs include an anode electrode, a cathode electrode, and a separator. The anode electrode includes active material arranged on opposite sides of a current collector. The cathode electrode includes cathode active material arranged on opposite sides of a current collector. SUMMARY

[0005] In features, a clutch control system for a vehicle includes a reset module configured to selectively initiate a reset operation of a clutch actuator of a clutch that clutches an electric propulsion motor to a gear set and unclutches the electric propulsion motor from the gear set, a target position module configured to perform the reset operation by setting a target position of the clutch actuator to follow a predetermined position profile of the reset operation, the reset operation including (a) opening an orifice between a hydraulic fluid reservoir and a pressure chamber of the clutch actuator (b) closing the orifice after the opening; and a clutch control module configured to actuate the clutch actuator based on the target position, thereby performing the reset operation.

[0006] In further features, the reset module is configured to initiate the reset operation when the vehicle is in one of parked and neutral.

[0007] In further features, the reset module is configured to initiate the reset operation when a time period since a last reset operation is greater than a predetermined time period.

[0008] In further features, the reset module is configured to set the predetermined period based on a temperature of the clutch actuator.

[0009] In further features, the reset module is configured to initiate the reset operation when clutch performance degradation is detected.

[0010] In further features, the reset module is configured to detect clutch performance degradation based on at least one of (a) a pressure of hydraulic fluid of the clutch actuator and (b) a jerk of the vehicle.

[0011] In further features, the reset module is configured to selectively initiate the reset operation when the clutch is disengaged such that the electric propulsion motor is decoupled from the gear set.

[0012] In further features, the reset module is configured to initiate the reset operation when a period since a last reset operation is greater than a predetermined period.

[0013] In further features, the reset module is configured to set the predetermined period based on a temperature of the clutch actuator.

[0014] In further features, the reset module is configured to initiate the reset operation when clutch performance degradation is detected.

[0015] In further features, the target position module is configured to adjust the predetermined position profile based on a temperature of the clutch actuator.

[0016] In further features, the target position module is configured to adjust the target position according to the predetermined position profile at a first rate during a first period of the reset operation during opening of the aperture.

[0017] In further features, the target position module is configured to adjust the target position according to the predetermined position profile at a second rate during a second period of the reset operation during opening of the aperture, where the second period is after the first period and the second rate is less than the first rate.

[0018] In further features, the target position module is configured to adjust the target position according to the predetermined position profile at a third rate during a third period of the reset operation during opening of the aperture, where the third period is after the second period and the third rate is greater than the second rate.

[0019] In another feature, the target position module is configured to adjust the target position at a fourth rate during a fourth period of the reset operation according to the predetermined position profile during the opening of the orifice, wherein the fourth period is after the third period and the fourth rate is greater than the third rate.

[0020] In another feature, the target position module is configured to keep the target position fixed during a fifth period of the reset operation while the orifice is open, wherein the fifth period is after the fourth period.

[0021] In another feature, the target position module is configured to adjust the target position at a fifth rate during a sixth period of the reset operation, based on the predetermined position profile, during the closing of the orifice, wherein the sixth period is after the fifth period.

[0022] In another feature, the clutch control module is configured to prevent the clutch from shifting during the reset operation.

[0023] In another feature, the target position module is configured to adjust the target position at a first rate when the piston of the clutch actuator is not adjacent to the orifice, and at a second rate when the piston is adjacent to the orifice, wherein the second rate is slower than the first rate.

[0024] In one feature, a clutch control method for a vehicle includes: selectively engaging a clutch actuator of a clutch that engages an electric propulsion motor with and disengages the electric propulsion motor from the gear set; performing the reset operation by setting a target position of the clutch actuator to follow a predetermined position profile of the reset operation, the reset operation including (a) opening an orifice between a hydraulic fluid reservoir and a pressure chamber of the clutch actuator and (b) closing the orifice after the opening; and actuating the clutch actuator based on the target position, thereby performing the reset operation.

[0025] Further areas of applicability of this disclosure will become clear from the detailed description, claims, and drawings. The detailed description and specific examples are intended for illustrative purposes only and are not intended to limit the scope of this disclosure. Attached Figure Description

[0026] This disclosure will become more fully understood through detailed description and accompanying drawings, in which:

[0027] Figure 1 This is a functional block diagram of an exemplary vehicle system;

[0028] Figure 2 This is a functional block diagram of an exemplary propulsion control system;

[0029] Figure 3 and 4 This is a cross-sectional view of an exemplary implementation of a clutch actuator;

[0030] Figure 5 This is a functional block diagram of an exemplary implementation of the clutch control module;

[0031] Figure 6 This is a time series of exemplary positions of a predetermined position profile used for the reset operation; and

[0032] Figure 7 This is a flowchart depicting an exemplary method for performing a reset operation.

[0033] In the accompanying drawings, reference numerals may be reused to identify similar and / or identical elements. Detailed Implementation

[0034] The vehicle may include one or more electric motors, such as those for propulsion. The transmission may include two or more different gear sets. Clutches are used to couple the electric motors to the gear sets for vehicle propulsion and to decouple the electric motors from the gear sets for vehicle propulsion. Clutch actuators actuate the clutches individually.

[0035] The pressure in the clutch actuator can drift over time. A reset operation can be performed periodically to open the pressure chamber of the clutch actuator for the reservoir, thereby resetting the pressure inside the chamber to the baseline pressure.

[0036] According to this application, the clutch control module controls the actuation of the clutch actuator used for reset operation to minimize pressure fluctuations when the pressure chamber is opened for the reservoir and closed for the reservoir.

[0037] Now refer to Figure 1 A functional block diagram of an exemplary vehicle system is presented. Although a vehicle system for a hybrid vehicle is shown and will be described, this disclosure is also applicable to electric vehicles (including pure electric vehicles) that do not include an internal combustion engine, fuel cell vehicles, autonomous vehicles, and other types of vehicles. Furthermore, although vehicle examples are provided, this application is also applicable to non-vehicle implementations.

[0038] Engine 102 combusts an air / fuel mixture to generate drive torque. Engine control module (ECM) 114 controls engine 102. For example, ECM 114 controls the actuation of engine actuators such as throttle valves, one or more spark plugs, one or more fuel injectors, valve actuators, camshaft phasers, exhaust gas recirculation (EGR) valves, one or more turbochargers, and other suitable engine actuators. In some types of vehicles (e.g., electric vehicles), engine 102 may be omitted.

[0039] Engine 102 can output torque to transmission 195. Transmission control module (TCM) 194 controls the operation of transmission 195. For example, TCM 194 can control gear selection in transmission 195 and one or more torque transmission devices (e.g., torque converters, one or more clutches, etc.).

[0040] The vehicle system includes one or more electric motors, such as motor 198. The electric motor can function as either a generator or a motor at a given time. When used as a generator, the motor converts mechanical energy into electrical energy. This electrical energy can be used, for example, to charge battery 199. When used as a motor, the motor generates torque, which can be used, for example, to propel the vehicle. Although an example of one electric motor is provided, a vehicle may include more than one electric motor. In various implementations, motor 198 may be used, for example, to start engine 102 via a belt.

[0041] The motor control module 196 controls the power flow from the battery 199 to the electric motor 198 and from the electric motor 198 to the battery 199. The motor control module 196 applies electrical power from the battery 199 to the electric motor 198 to cause the electric motor 198 to output positive torque, such as for vehicle propulsion or for starting the engine 102. The battery 199 may include, for example, one or more battery modules. Each battery module may include multiple battery cells.

[0042] The electric motor 198 can output torque, for example, to the input shaft of the transmission 195, or to the output shaft of the transmission 195, or to the wheels of the vehicle. Two or more clutches (such as clutch 200) can be engaged to couple the electric motor 198 to the transmission 195, and disengaged to decouple the electric motor 198 from different gear sets of the transmission 195. The gear sets can be implemented between the output of clutch 200 and the input of the transmission 195 to provide two or more predetermined ratios between the rotation of the electric motor 198 and the rotation of the input of the transmission 195. The transmission 195 may also be referred to as a gearbox.

[0043] The motor control module 196 can also selectively control the electric motor 198 to convert the vehicle's mechanical energy into electrical energy. More specifically, when the electric motor 198 is driven by the transmission 195 and the motor control module 196 is not applying power from the battery 199 to the electric motor 198, the electric motor 198 generates and outputs power. The motor control module 196 can charge the battery 199 using the power output from the electric motor 198.

[0044] The vehicle may include a charging port 190. A power source (such as a charging station, another vehicle, or another suitable power source) may be connected to and charge the battery 199 via the charging port 190. The battery 199 may also be used to power other devices (e.g., other vehicles) via the charging port 190.

[0045] Now refer to Figure 2 A functional block diagram of an exemplary propulsion control system is presented. The driver torque module 204 determines a driver torque request 208 based on driver input 212. Driver input 212 may include, for example, accelerator pedal position (APP), brake pedal position (BPP), cruise control input, and / or autonomous input. In various implementations, the cruise control input may be provided by an adaptive cruise control system that attempts to maintain at least a predetermined distance between the vehicle and objects in its path. Autonomous input may be provided by an autonomous driving system that controls the movement of the vehicle from one location to another while avoiding objects and other vehicles. The driver torque module 204 determines the driver torque request 208 based on one or more lookup tables that correlate driver input with the driver torque request. APP and BPP can be measured using one or more APP sensors and BPP sensors, respectively.

[0046] Driver torque request 208 may be an axle torque request. Axle torque (including axle torque request) refers to the torque at the wheels. As discussed further below, propulsion torque (including propulsion torque request) differs from axle torque because propulsion torque can refer to the torque at the transmission input shaft.

[0047] The axle torque arbitration module 216 arbitrates between the driver torque request 208 and other axle torque requests 220. Axle torque (torque at the wheels) can be generated by various sources, including engine 102 and / or one or more electric motors, such as electric motor 198. Examples of the other axle torque requests 220 include, but are not limited to, torque reduction requests requested by the traction control system when positive wheel slip is detected, torque increase requests to counteract negative wheel slip, brake management requests to reduce axle torque to ensure that the axle torque does not exceed the brakes' ability to hold the vehicle when it is stopped, and vehicle overspeed torque requests to reduce axle torque to prevent the vehicle from exceeding a predetermined speed. Based on the result of the arbitration between the received axle torque requests 208 and 220, the axle torque arbitration module 216 outputs one or more axle torque requests 224.

[0048] In a hybrid vehicle, the hybrid module 228 determines how much of the one or more axle torque requests 224 should be generated by the engine 102 and how much of the one or more axle torque requests 224 should be generated by the electric motor 198. For simplicity, this will be combined with... Figure 2 The example continues with the example of electric motor 198, but multiple electric motors may be included. Hybrid module 228 outputs one or more engine torque requests 232 to propulsion torque arbitration module 236. Engine torque request 232 indicates the requested torque output of engine 102.

[0049] Hybrid module 228 also outputs motor torque request 234 to motor control module 196. Motor torque request 234 indicates the requested torque output (positive or negative) of motor 198. In vehicles where engine 102 is omitted (e.g., electric vehicles) or not connected to output propulsion torque for the vehicle, axle torque arbitration module 216 may output an axle torque request, and motor torque request 234 may be equal to that axle torque request. In the example of an electric vehicle, ECM 114 may be omitted, and driver torque module 204 and axle torque arbitration module 216 may be implemented within motor control module 196.

[0050] In an electric vehicle, the driver torque module 204 can input the driver torque request 208 to the motor control module 196, and components related to controlling the engine actuator can be omitted. In an example with multiple electric motors, the motor control module 196 can determine how much torque should be generated by each of the electric motors. The electric motors can be controlled to achieve the same or different amounts of torque.

[0051] The propulsion torque arbitration module 236 converts the engine torque request 232 from the axle torque domain (torque at the wheels) to the propulsion torque domain (e.g., torque at the input shaft of the transmission). The propulsion torque arbitration module 236 arbitrates the converted torque request with other propulsion torque requests 240. Examples of these other propulsion torque requests 240 include, but are not limited to, torque reduction requests for engine overspeed protection and torque increases requests for stall prevention. The propulsion torque arbitration module 236 may output one or more propulsion torque requests 244 as the result of the arbitration.

[0052] Based on the thrust torque request 244, the actuator control module 248 controls the actuators 252 of the engine 102. For example, based on the thrust torque request 244, the actuator control module 248 may control the opening of the throttle valve, the timing of the spark provided by the spark plug, the timing and amount of fuel injected by the fuel injector, cylinder actuation / deactivation, intake and exhaust valve phasing, the output of one or more boosting devices (e.g., turbochargers, superchargers, etc.), the opening of the EGR valve, and / or one or more other engine actuators. In various implementations, the thrust torque request 244 may be adjusted or modified, such as to create a torque reserve, before being used by the actuator control module 248.

[0053] Based on the motor torque request 234, the motor control module 196 controls the switching of the inverter module 256. The switching of the inverter module 256 controls the power flow from the battery 199 to the motor 198. Thus, the switching of the inverter module 256 controls the torque output of the motor 198. The inverter module 256 also converts the power generated by the motor 198 and outputs the power to the battery 199 for example, to charge the battery 199.

[0054] For example, based on using a closed-loop control module to adjust the torque 260 output of motor 198 toward motor torque request 234 or to adjust the torque 260 output of motor 198 to motor torque request 234, motor control module 196 can control the switching of inverter module 256. For example, the closed-loop control module may include a proportional-integral (PI) control module or another suitable type of closed-loop control module. The torque 260 of motor 198 can be measured using a torque sensor, or estimated (e.g., by motor control module 196) based on one or more operating parameters, such as using one or more equations and / or lookup tables.

[0055] Inverter module 256 includes the plurality of switches. Motor control module 196 switches to convert DC power from battery 199 into alternating current (AC) power and apply the AC power to motor 198 to drive motor 198. For example, inverter module 256 may convert DC power from battery 199 into n-phase AC power and apply the n-phase AC power to n stator windings of motor 198 (e.g., a, b, and c or u, v, and w). In various implementations, n equals 3. The magnetic flux generated by the current flowing through the stator windings drives the rotor of motor 198. The rotor is connected to the output shaft of motor 198 and drives the rotation of the output shaft of motor 198.

[0056] In various implementations, one or more filters may be electrically connected between inverter module 256 and battery 199. These filters may be implemented to, for example, filter power flow to and from battery 199. As an example, a filter comprising one or more capacitors and resistors may be electrically connected in parallel with inverter module 256 and battery 199.

[0057] Although battery 199 has been discussed in conjunction with a vehicle, this application is also applicable to the use of battery 199 in other types of devices (including non-vehicle applications).

[0058] As discussed above, clutch 200 is used to engage and disengage motor 198 from different gear sets 280, respectively. For example, a first clutch can be actuated to engage and disengage motor 198 from a first gear set. A second clutch can be actuated to engage and disengage motor 198 from a second gear set. Although an example of two clutches and two gear sets is provided, this application applies to N clutches and N corresponding gear sets, where N is an integer greater than or equal to 2.

[0059] Clutch actuator 284 actuates the corresponding clutch 200. Clutch actuator 284 may include, for example, an electric motor or another suitable type of actuator.

[0060] The clutch control module 288 controls the actuation of the clutch actuator 284, and thus controls the clutch 200. The clutch control module 288 can control the clutch 200 such that only one clutch is engaged at any given time. However, in some cases, both clutches can be disengaged simultaneously.

[0061] Figure 3 and 4This is a cross-sectional view of an exemplary implementation of one of the clutch actuators 284. The clutch actuator 284 may be the same or similar and may operate in the same manner.

[0062] Hydraulic fluid is stored in reservoir 304. The body 308 of clutch actuator 284 includes an orifice 312 in fluid communication with reservoir 304. Actuator 316 (such as an electric motor) moves piston 320 linearly. Plunger 324 is connected to piston 320 and moves with piston 320. Actuator 316 moves piston 320 and plunger 324 to adjust the pressure within pressure chamber 328 and to block or open orifice 312 for reservoir 304. Figure 3 The plunger 324 is positioned to block the orifice 312, preventing fluid coupling between the reservoir 304 and the pressure chamber 328. Figure 4 The plunger 324 is positioned such that the orifice 304 is not blocked and the reservoir 304 and pressure chamber 328 are in fluid communication. When the orifice 304 is open for a period of time, the pressure in the reservoir 304 and the pressure in the pressure chamber 328 will become the same.

[0063] The movement of plunger 324 controls the movement of the second piston 332. More specifically, actuator 316... Figure 3 and 4 Moving the plunger 324 to the right causes the second piston 332 to move to the right, while simultaneously blocking the orifice 312. Moving the plunger 324 to the left causes the second piston 332 to move to the left.

[0064] A biasing device (such as one or more springs) biases the second piston 332 to the left. An arm 340 is coupled to the second piston 332 and moves with it in a linear manner. One or more flexible devices 344 (such as one or more spacers and / or waveplates) may be positioned between the arm 340 and a portion of the second piston 332.

[0065] Arm 348 engages the load cell 348 on the back plate of clutch 200. Rightward movement of the second piston 332 moves arm 340 to the right into load cell 348, engaging clutch 200 and thereby coupling motor 198 to gear set. Leftward movement of the second piston 332 causes leftward movement of arm 340, disengaging clutch 200 and thus decoupling motor 198 from gear set. When coupled, motor 198 transmits torque to gear set, and rotation of motor 198 causes rotation of gear set. When decoupled, motor 198 does not transmit torque to gear set, and rotation of motor 198 does not cause rotation of gear set.

[0066] Temperature sensor 352 measures the temperature of the fluid within pressure chamber 328. Pressure sensor 356 measures the pressure of the fluid within pressure chamber 328. One or more position sensors 360, such as optically, measure the position of the second piston 332 and / or arm 340.

[0067] When orifice 312 is closed, the pressure within pressure chamber 328 can naturally drift over time. A reset operation can be performed by clutch control module 288 in some cases to open orifice 312 and equalize the pressure within pressure chamber 328 with the pressure within reservoir 304. However, pressure fluctuations may occur when plunger 324 begins to open orifice 312, and when plunger 324 transitions orifice 312 from partially open to fully closed.

[0068] The clutch control module 288 controls the position of the clutch actuator 284 (e.g., the position of the second piston 332 or the position of the arm 340) according to a predetermined profile for each reset operation. This minimizes pressure fluctuations associated with the opening and closing of the orifice 312.

[0069] Figure 5 This is a functional block diagram of an exemplary implementation of the clutch control module 288. Based on one or more operating parameters 512 and / or requests, the target pressure module 504 determines a target pressure 508 within the pressure chamber 328. For example, the target pressure module 504 can determine the target pressure 508 by using one or more lookup tables and / or equations that are input in relation to the target pressure.

[0070] Based on the target position 520, the target position module 516 determines the target position 520 of the clutch actuator 284 (e.g., the position of the second piston 332 or the position of the arm 340). For example, the target position module 516 can determine the target position 520 using one of the lookup tables and equations that associate target pressure with target position.

[0071] Based on the difference (subtraction) between the pressure 532 within pressure chamber 328 and the target pressure 508, the first adjustment module 524 determines a first adjustment 528. Pressure 532 is measured by pressure sensor 356. The first adjustment 528 can be, for example, an offset value or a scalar value.

[0072] Based on the difference (subtraction) between the position 542 of the clutch actuator 284 and the target position 520, the second adjustment module 536 determines a second adjustment 540. The position 542 is measured via one or more position sensors 558. The second adjustment 540 can be, for example, an offset value or a scalar value.

[0073] Based on the target position 520, the first adjustment 528, and the second adjustment 540, the adjustment module 544 determines the target position 548 for adjustment. In the offset example, the adjustment module 544 may set the target position 548 based on the target position 520 plus the first adjustment 528 plus the second adjustment 540, or set the target position 548 to be equal to the target position 520 plus the first adjustment 528 plus the second adjustment 540. In the scalar example, the adjustment module 544 may set the target position 548 based on the target position 520 multiplied by the first adjustment 528 and then multiplied by the second adjustment 540, or set the target position 548 to be equal to the target position 520 multiplied by the first adjustment 528 and then multiplied by the second adjustment 540.

[0074] The actuator control module 552 actuates the clutch actuator 284 to the adjusted target position 548. For example, the actuator control module 552 may apply power (e.g., from the battery 199) to the actuator (e.g., the electric motor 316) to adjust the position 544 to the adjusted target position 548 in a linear manner.

[0075] The reset module 560 selectively initiates the execution of a reset operation for the clutch actuator 284. During the reset operation, the orifice 312 is opened and then closed again. The reset module 560 initiates the execution of the reset operation by generating a reset indicator 564 (e.g., setting the reset indicator 564 to a first state).

[0076] In response to the generation of the reset indicator 564, for a reset operation, the target position module 516 sets the target position 520 to a predetermined profile over time. The predetermined profile includes a time series of the target position for completing the reset operation. The predetermined profile may be stored in memory. In various implementations, the target position module 516 can scale the target position of the target profile using a scalar value, and determines the scalar value based on the temperature 570 within the pressure chamber 328 measured by the temperature sensor 352. The target position module 516 can determine the scalar value using one of a lookup table and equation that correlates temperature with the scalar value. For example, the target position module 516 can decrease the scalar value as the temperature increases, and vice versa. The adjustment module 544 can set the adjusted target position 548 to the target position 520 during the reset operation.

[0077] Figure 6 A time series of exemplary positions including the predetermined position contour. As time 608 passes, position 604 is drawn. Orifice 312 is initially closed. Following the predetermined contour 612, target position module 516 changes orifice 312 to fully open at time 616.

[0078] During the first period of the reset operation between the initial time and time 620, the target position module 612 adjusts the target position 520 to open the orifice 312 and in the first direction (in Figure 3 In the example, piston 320 is moved to the left at a first predetermined rate. During the second period of the reset operation between time 620 and time 624, target position module 612 adjusts target position 520 to open orifice 312 and moves piston 320 in a first direction at a second predetermined rate. The second predetermined rate is less than the first predetermined rate.

[0079] During the third time period of the reset operation between time 624 and time 628, the target position module 612 adjusts the target position 520 to open the orifice 312 and moves the piston 320 in the first direction at a third predetermined rate. The third predetermined rate may be greater than the second predetermined rate and may be greater than the first predetermined rate.

[0080] During the fourth period of the reset operation between time 628 and time 616, the target position module 612 adjusts the target position 520 to open the orifice 312 and moves the piston 320 in the first direction at a fourth predetermined rate. The fourth predetermined rate may be greater than the third predetermined rate, greater than the second predetermined rate, and greater than the first predetermined rate.

[0081] As discussed above, orifice 312 is fully open at time 616. The target position module 612 maintains the target position 520 fixed during the dwell (fifth) period between time 616 and time 632. This allows the pressure within the actuator and the pressure within the reservoir 304 to be equal. The first period may be the same as or greater than the second period. The third period may be less than the second period. The fourth period may be greater than the third period and less than the second period.

[0082] After the dwell time has passed, the target position module 612 begins to close the orifice 312 at time 632.

[0083] During the sixth time period of the reset operation between time 632 and time 636, the target position module 612 adjusts the target position 520 to close the orifice 312 and moves the piston 320 in a second direction opposite to the first direction at a fifth predetermined rate. During the seventh time period of the reset operation between time 636 and time 640, the target position module 612 adjusts the target position 520 to close the orifice 312 and moves the piston 320 in the second direction at a sixth predetermined rate. The sixth predetermined rate may be less than the fifth predetermined rate. The seventh time period may be longer than the sixth time period.

[0084] During the eighth time period of the reset operation between time 640 and time 644, the target position module 612 adjusts the target position 520 to close the orifice 312 and moves the piston 320 in the second direction at a seventh predetermined rate. The seventh predetermined rate may be less than the sixth predetermined rate and less than the fifth predetermined rate. The eighth time period may be less than the sixth time period and less than the seventh time period. The reset operation may be completed at 644, at which time the orifice 312 can be fully closed.

[0085] Figure 6 It also includes an exemplary graph of pressure 668 versus time 670. The pressure may initially be high at 674. The pressure may be reduced (e.g., in steps) to 678. The pressure may be increased at a first rate 680. The pressure may be increased at a second rate 682, which is less than the first rate 680. The pressure may be increased, for example, in steps, to 684. Generally, the piston may be rapidly restored, and its return to its original position may be staged, and in particular, it may be moved slowly through the orifice for consistency and to reduce pressure fluctuations.

[0086] Figure 7 This is a flowchart depicting an exemplary method for performing a reset operation. Control may begin at 704, where the reset module 560 determines whether the vehicle is in park or neutral. If 704 is true, control may continue to 708. If 704 is false, control may continue to 720, which is discussed further below.

[0087] At 708, the reset module 560 can determine whether at least one of (a) the time period since the last reset operation was completed is greater than a predetermined time period and (b) clutch performance degradation has been detected. If 708 is true, the reset module 560 generates a reset indicator 564, and control can continue to 712. If 708 is false, the reset operation may not be performed at that time, and control can end. Based on temperature 570, the reset module 560 can determine the predetermined time period, such as using one of an equation and lookup table that correlates temperature with time period. When the temperature increases, the reset module 560 can, for example, reduce the predetermined time period, and vice versa. For example, based on at least one of (a) pressure 532 and (b) vehicle vibration, the reset module 560 can detect clutch performance degradation. For example, when pressure 532 meets one or more predetermined conditions and / or vibration meets one or more predetermined conditions, the reset module 560 can determine that clutch performance degradation has occurred.

[0088] At 712, the target position module 516 determines the predetermined contour of the target position 520 for the reset operation, as discussed above. At 716, the target position module 516 adjusts the target position 520 to conform to the predetermined contour of the reset operation. The actuator control module 552 actuates the clutch actuator 284 to conform to the target position 520, thereby performing the reset operation.

[0089] At 720, reset module 560 can determine whether the clutch is currently disengaged and whether at least one of (a) the time since the last reset operation was completed is greater than a predetermined time period and (b) clutch performance degradation has been detected. If 720 is true, reset module 560 generates reset indicator 564, and control can continue to 724. If 720 is false, the reset operation may not be performed at that time, and control may terminate. Based on temperature 570, reset module 560 can determine the predetermined time period, such as using one of an equation and lookup table that correlates temperature with time period. When the temperature increases, reset module 560 can, for example, reduce the predetermined time period, and vice versa. For example, reset module 560 can detect clutch performance degradation based on at least one of (a) pressure 532 and (b) vehicle vibration. For example, when pressure 532 meets one or more predetermined conditions and / or vibration meets one or more predetermined conditions, reset module 560 can determine that clutch performance degradation has occurred.

[0090] At 728, the target position module 516 determines the predetermined contour of the target position 520 for the reset operation, as discussed above. At 732, the target position module 516 adjusts the target position 520 to conform to the predetermined contour of the reset operation. The actuator control module 552 actuates the clutch actuator 284 to conform to the target position 520, thereby performing the reset operation. During the execution of the reset operation at 732, the reset module 560 also prohibits clutch shifting (e.g., engagement). For example, the reset module 560 may delay the scheduled shifting involving the clutch until the reset procedure is completed.

[0091] The foregoing description is illustrative in nature and is in no way intended to limit this disclosure, its application, or use. The broad teachings of this disclosure can be implemented in various forms. Therefore, although this disclosure includes specific examples, its true scope should not be limited thereto, as other modifications will become apparent upon studying the accompanying drawings, specification, and the following claims. It should be understood that one or more steps within the method may be performed in a different order (or simultaneously) without altering the principles of this disclosure. Furthermore, while each embodiment in the examples has been described above as having certain features, any one or more of those features described for any embodiment of this disclosure can be implemented in any embodiment of other embodiments, and / or combined with features of any embodiment of other embodiments, even if such combination is not explicitly described. In other words, the described embodiments are not mutually exclusive, and the arrangement of one or more embodiments with each other remains within the scope of this disclosure.

[0092] Various terms are used to describe spatial and functional relationships between elements (e.g., between modules, circuit elements, semiconductor layers, etc.), including “connection,” “engagement,” “coupling,” “adjacent,” “next to,” “on top of,” “above,” “below,” and “placed.” Unless explicitly described as “direct,” when describing the relationship between the first and second elements in the above disclosure, the relationship can be a direct relationship where no other intermediary element is present between the first and second elements, but it can also be an indirect relationship where one or more intermediary elements are present (spatially or functionally) between the first and second elements. As used herein, the phrases A, B, and C at least one should be interpreted as referring to the logic (A OR B OR C) using non-exclusive logic OR, and should not be interpreted as referring to “at least one of A, at least one of B, and at least one of C.”

[0093] In the accompanying drawings, as indicated by the arrow tips, the direction of the arrows generally shows the flow of information of interest to the illustration (such as data or instructions). For example, when components A and B exchange various information, but the information transmitted from component A to component B is relevant to the illustration, the arrow may point from component A to component B. This unidirectional arrow does not imply that no other information is transmitted from component B to component A. Furthermore, for information sent from component A to component B, component B may send a request for said information or an acknowledgment of receipt of said information to component A.

[0094] In this application, which includes the following definitions, the term "module" or "controller" may be replaced by the term "circuit". The term "module" may refer to, be part of, or include the following: application-specific integrated circuit (ASIC); digital, analog, or mixed-signal analog / digital discrete circuit; digital, analog, or mixed-signal analog / digital integrated circuit; combinational logic circuit; field-programmable gate array (FPGA); processor circuit (shared, dedicated, or group) that executes code; memory circuit (shared, dedicated, or group) that stores code executed by the processor circuit; other suitable hardware components that provide the described functionality; or combinations of some or all of the above, such as in a system-on-a-chip.

[0095] A module may include one or more interface circuits. In some examples, the interface circuits may include wired or wireless interfaces connected to a local area network (LAN), the Internet, a wide area network (WAN), or a combination thereof. The functionality of any given module in this disclosure may be distributed among multiple modules connected via interface circuits. For example, multiple modules may allow for load balancing. In another example, a server (also referred to as a remote or cloud) module may perform some functions on behalf of a client module.

[0096] As used above, the term "code" can include software, firmware, and / or microcode, and can refer to programs, routines, functions, classes, data structures, and / or objects. The term "shared processor circuit" covers a single processor circuit that executes some or all of the code from multiple modules. The term "group processor circuit" covers a processor circuit that, in conjunction with additional processor circuitry, executes some or all of the code from one or more modules. References to multiple processor circuits cover multiple processor circuits on a discrete die, multiple processor circuits on a single die, multiple cores of a single processor circuit, multiple threads of a single processor circuit, or a combination of the above. The term "shared memory circuit" covers a single memory circuit that stores some or all of the code from multiple modules. The term "group memory circuit" covers a memory circuit that, in conjunction with additional memory, stores some or all of the code from one or more modules.

[0097] The term memory circuit is a subset of the term computer-readable medium. As used herein, the term computer-readable medium does not cover transient electrical or electromagnetic signals propagating through a medium (such as on a carrier wave); the term computer-readable medium can therefore be considered tangible and non-transient. Non-limiting examples of non-transient tangible computer-readable media are non-volatile memory circuits (such as flash memory circuits, erasable programmable read-only memory circuits, or mask read-only memory circuits), volatile memory circuits (such as static random access memory circuits or dynamic random access memory circuits), magnetic storage media (such as analog or digital magnetic tape or hard disk drives), and optical storage media (such as CDs, DVDs, or Blu-ray discs).

[0098] The apparatus and methods described in this application can be implemented, in part or in whole, by a dedicated computer created by configuring a general-purpose computer to perform one or more specific functions embodied in a computer program. The functional blocks, flowchart components, and other elements described above serve as software specifications that can be converted into computer programs through routine work by those skilled in the art or programmers.

[0099] A computer program includes processor-executable instructions stored on at least one non-transitory tangible computer-readable medium. A computer program may also include or depend on stored data. A computer program may encompass a basic input / output system (BIOS) for interacting with the hardware of a special-purpose computer, device drivers for interacting with specific devices of the special-purpose computer, one or more operating systems, user applications, background services, background applications, etc.

[0100] Computer programs may include: (i) descriptive text to be parsed, such as HTML (Hypertext Markup Language), XML (Extensible Markup Language), or JSON (JavaScript Object Notation); (ii) assembly code; (iii) object code generated from source code by a compiler; (iv) source code for execution by an interpreter; and (v) source code for compilation and execution by a just-in-time (JIT) compiler, etc. As an example only, source code may be written using syntax from languages ​​including C, C++, C#, Objective-C, Swift, Haskell, Go, SQL, R, Lisp, etc. Fortran, Perl, Pascal, Curl, OCaml, HTML5 (Hypertext Markup Language, Fifth Revision), Ada, ASP (Dynamic Server Pages), PHP (PHP: Hypertext Preprocessor), Scala, Eiffel, Smalltalk, Erlang, Ruby, Lua, MATLAB, SIMULINK and

Claims

1. A clutch control system for a vehicle, comprising: The reset module is configured to selectively engage the reset operation of the clutch actuator of the vehicle's clutch, the clutch engaging the vehicle's electric propulsion motor with the vehicle's gear set and disengaging the vehicle's electric propulsion motor from the vehicle's gear set; The target position module is configured to perform the reset operation by setting a target position for the clutch actuator to follow a predetermined position profile of the reset operation. The reset operation includes (a) opening an orifice between the hydraulic fluid reservoir and the pressure chamber of the clutch actuator, and (b) closing the orifice after the opening. and The clutch control module is configured to actuate the clutch actuator based on the target position, thereby performing the reset operation.

2. The clutch control system of claim 1, wherein when the vehicle is in either park or neutral, the reset module is configured to selectively initiate the reset operation.

3. The clutch control system of claim 2, wherein the reset module is configured to initiate the reset operation when the time period since the last reset operation is greater than a predetermined time period.

4. The clutch control system of claim 3, wherein the reset module is configured to set the predetermined time period based on the temperature of the clutch actuator.

5. The clutch control system of claim 2, wherein when clutch performance degradation is detected, the reset module is configured to initiate the reset operation.

6. The clutch control system of claim 5, wherein the reset module is configured to detect clutch performance degradation based on at least one of (a) the pressure of the hydraulic fluid of the clutch actuator and (b) the vibration of the vehicle.

7. The clutch control system of claim 1, wherein when the clutch is disengaged to decouple the electric propulsion motor from the gear set, the reset module is configured to selectively initiate the reset operation.

8. The clutch control system of claim 7, wherein the reset module is configured to initiate the reset operation when the time period since the last reset operation is greater than a predetermined time period.

9. The clutch control system of claim 8, wherein the reset module is configured to set the predetermined time period based on the temperature of the clutch actuator.

10. The clutch control system of claim 7, wherein when clutch performance degradation is detected, the reset module is configured to initiate the reset operation.

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