Regeneration of a gas particulate filter with retarded fuel cut implementation

Abstract

Systems and methods provide for deceleration fuel cut regenerations of a gas particulate filter. A powertrain system includes an exhaust system including a gas particulate filter configured to collect particulate matter from an exhaust stream of the powertrain system. A temperature sensor is configured to monitor a temperature of the gas particulate filter. A load monitor, such as a sensor and / or a model, is configured to provide a load input of a particulate load of the gas particulate filter. At least one controller is configured to: determine whether the gas particulate filter requires regeneration by comparing the load input to a stored value; effect a warm-up of the gas particulate filter when the determination indicates that the gas particulate filter requires the regeneration; and initiate the regeneration when a value received from the temperature sensor satisfies a minimum threshold level.

Description

Regeneration achieved by decelerating fuel cut-off for particulate filters Technical Field

[0001] This disclosure generally relates to the regeneration of a gas particulate filter (GPF) in the exhaust system of a gasoline engine, and more specifically to regeneration via decelerated fuel cutoff (DFCO). Background Technology

[0002] Gasoline engines can be equipped with an exhaust system that includes a gas permeable powder (GPPF) to remove particulate matter from the exhaust stream. One type of engine of this type is a gasoline direct injection engine. The GPF may include a housing containing a multi-channel substrate / medium that captures particles as exhaust gas passes through. One such substrate may include a honeycomb structure through which exhaust gas passes. Accumulated particles can be removed, for example, by subjecting the cells to conditions including temperature and gas composition to burn off the particles.

[0003] GPF regeneration can be achieved passively, where particulate capture and cell regeneration occur continuously during the operation of the associated vehicle / engine in a normal driving cycle. When a gasoline engine is paired with one or more electric traction motors, such as in a hybrid arrangement, the gasoline engine can operate intermittently and can be shut off when regeneration can be achieved in other ways. Therefore, purely passive regeneration may not be sufficient to provide the preferred regeneration level / timing.

[0004] For example, active regeneration cycles might be required when passive regeneration is initiated abruptly. Active regeneration cycles may require operating the vehicle's powertrain in an intrusive and controlled manner outside of normal driving cycles, which is undesirable. When active regeneration is initiated under certain circumstances, such as during the first mileage of operation of an associated vehicle, an upsizing (Ki) factor can be added to the vehicle's certification. The Ki factor represents the ratio of emissions from the cycle with regeneration to emissions from all cycles and may involve a multiplier that adjusts the vehicle's measured emissions upwards for certification purposes. Therefore, the application of the Ki factor is to be avoided.

[0005] Therefore, it is desirable to provide improved methods and systems that enable passive GPF regeneration in hybrid propulsion arrangements while avoiding the need to apply the Ki factor. Furthermore, other desirable features and characteristics of the invention will become apparent from the following detailed description and appended claims, taken in conjunction with the accompanying drawings and the foregoing technical and background information. Summary of the Invention

[0006] Systems and methods for decelerating fuel cut-off regeneration of a gas particulate filter are disclosed. In several embodiments, a powertrain system enables the regeneration of the gas particulate filter and includes an exhaust system comprising the gas particulate filter, the exhaust system being configured to collect particulate matter from the exhaust flow of the powertrain system. A temperature sensor is configured to monitor the temperature of the gas particulate filter. A load monitor (such as a sensor and / or model) is configured to provide a load indication input of the particulate load of the gas particulate filter. At least one controller is configured to: determine whether the gas particulate filter needs regeneration by comparing the load input with a stored value; preheat the gas particulate filter when the determination indicates that the gas particulate filter needs regeneration; and enable regeneration when the value received from the temperature sensor meets a minimum threshold level.

[0007] In another embodiment, the powertrain system includes a gasoline engine, wherein the gasoline engine is configured to operate as a fuel-free air pump under deceleration fuel cut-off conditions when regeneration is enabled.

[0008] In another embodiment, before regeneration begins, the controller is configured to: determine whether any sensor malfunctions are active, including for the temperature sensor and for the load monitor; and determine whether the temperature of the gas particulate filter is above the calibration temperature, at which regeneration of the gas particulate filter is feasible.

[0009] In another implementation, before regeneration begins, the controller is configured to determine whether the speed of the vehicle in which the powertrain system is located is higher than a calibration speed, where the calibration speed is the minimum speed at which deceleration of the vehicle would feasiblely cause regeneration of the gas particulate filter.

[0010] In another embodiment, the powertrain system includes an engine having a throttle valve for controlling the air supplied to the engine and at least one injector for controlling the fuel supplied to the engine. The controller is configured to initiate engine operation to accelerate the preheating of the particulate filter by changing the air / fuel ratio supplied to the engine via the operation of the throttle valve and at least one injector.

[0011] In another embodiment, the injector is used to control the fuel supplied to the engine, wherein the controller is configured to initiate engine operation by supplying fuel via the injector in stages to accelerate the preheating of the gas particulate filter.

[0012] In another embodiment, at least one spark plug controls the initiation of combustion in the engine, wherein the controller is configured to initiate engine operation by altering the timing of combustion via at least one spark plug to accelerate the preheating of the gas particulate filter.

[0013] In another embodiment, the valve controls the air supplied to and from the engine, wherein the controller is configured to initiate engine operation by changing the phase angle of the valve to accelerate the preheating of the gas particulate filter.

[0014] In another embodiment, the powertrain system includes an internal combustion engine and an electric motor. A transmission system connects and disconnects the internal combustion engine from the drivetrain. The controller is configured to connect the internal combustion engine to the drivetrain via the transmission system during the regeneration of the gas particulate filter.

[0015] In another embodiment, the powertrain system includes an internal combustion engine and an electric motor, wherein the controller is configured to regenerate the gas particulate filter by decelerating the fuel cut-off of the internal combustion engine.

[0016] In several other embodiments, a method enables the regeneration of a powertrain system's particulate filter by decelerating fuel cutoff. The particulate filter collects particulate matter from the powertrain system's exhaust flow. A temperature sensor monitors the temperature of the particulate filter. A load monitor (such as a pressure sensor and / or a model) provides a load input of the particulate load on the particulate filter. A controller determines whether the particulate filter needs regeneration by comparing the load input with stored values. When it is determined that the particulate filter needs regeneration, the controller preheats the particulate filter. When the value received from the temperature sensor meets a minimum threshold level, the controller enables regeneration.

[0017] In another embodiment, when regeneration is performed, the controller operates the gasoline engine as an air pump without fuel under deceleration fuel cut-off conditions.

[0018] In another embodiment, the controller determines whether any sensor malfunctions are active before regeneration begins, including for the temperature sensor and the load monitor. Additionally, the controller determines whether the temperature of the gas particulate filter is higher than the calibrated temperature at which regeneration of the gas particulate filter is feasible.

[0019] In another implementation, the controller determines whether the speed of the vehicle in which the powertrain system is located is higher than a calibration speed before regeneration begins. The calibration speed is the minimum speed at which vehicle deceleration will practically cause the gas particulate filter to regenerate.

[0020] In another embodiment, the engine in the powertrain system has a throttle valve that controls the air supplied to the engine and an injector that controls the fuel supplied to the engine. The controller initiates engine operation to accelerate the preheating of the particulate filter by changing the air / fuel ratio supplied to the engine via the operation of the throttle valve and the injector.

[0021] In another embodiment, the engine is located in a powertrain system with injectors. The injectors control the fuel supply to the engine. The controller operates the engine to accelerate the preheating of the gas particulate filter by supplying fuel in stages via the injectors.

[0022] In another embodiment, the powertrain system provides an engine having at least one spark plug. A controller controls the initiation of combustion in the engine via the at least one spark plug. The controller initiates engine operation to accelerate the preheating of the particulate filter by altering the timing of combustion via the at least one spark plug.

[0023] In another embodiment, an engine is provided in the powertrain system, the engine having valves that control the air supplied to and from the engine. The controller initiates engine operation to accelerate the preheating of the gas particulate filter.

[0024] In another embodiment, an internal combustion engine is provided in the powertrain system. An electric motor is provided in the powertrain system. A transmission system is provided in the powertrain system for connecting and disconnecting the internal combustion engine from the drivetrain. During the regeneration of the gas particulate filter, the controller connects the internal combustion engine to the drivetrain via the transmission system.

[0025] In several other embodiments, the vehicle includes a hybrid powertrain having an internal combustion engine, an electric motor, and an exhaust system extending from the internal combustion engine. A particulate filter is disposed in the exhaust system to collect particulate matter. A temperature sensor is configured to monitor the temperature of the particulate filter. A load monitor is configured to provide a load input of the particulate load of the particulate filter. A controller is configured to: determine whether the particulate filter needs regeneration by comparing the load input with a stored value; preheat the particulate filter when the determination indicates that the particulate filter needs regeneration; enable the regeneration when the value received from the temperature sensor meets a minimum threshold level; and initiate the regeneration of the particulate filter by decelerating fuel cutoff, wherein the internal combustion engine operates as an air pump to supply oxygen to the particulate filter. Attached Figure Description

[0026] Exemplary embodiments will be described below in conjunction with the accompanying drawings, wherein the same reference numerals denote the same elements, and wherein:

[0027] Figure 1 is a functional diagram of a vehicle according to an exemplary embodiment, the vehicle including a hybrid powertrain and a control system for starting and executing a DFCO for GPF regeneration;

[0028] Figure 2 is a diagram of a DFCO model for the vehicle and hybrid powertrain of Figure 1 according to an exemplary embodiment;

[0029] Figure 3 is a data flow diagram of the DFCO model of Figure 2 in the case of the control system of Figure 1, according to an exemplary embodiment; and

[0030] Figure 4 is a flowchart of a process for initiating a DFCO request according to an exemplary embodiment, which can be used in conjunction with the vehicle and control system of Figure 1. Detailed Implementation

[0031] The detailed description below is merely exemplary in nature and is not intended to limit application or use. Furthermore, it is not intended to be bound by any express or implied theory presented in the foregoing technical field, background art, summary of the invention, or the following detailed description. As used herein, the term "module" refers individually or in any combination of any hardware, software, firmware, electronic control components, processing logic, and / or processor devices, including but not limited to: application-specific integrated circuits, electronic circuits, processors (shared, dedicated, or grouped) and memories executing one or more software or firmware programs, combinational logic circuits, and / or other suitable components that provide the described functionality.

[0032] This document describes embodiments of the present disclosure in terms of functional and / or logical block components and various processing steps. It should be understood that such block components can be implemented by any number of hardware, software, and / or firmware components configured to perform specified functions. For example, embodiments of the present disclosure may employ various integrated circuit components, such as memory elements, digital signal processing elements, logic elements, lookup tables, etc., which can perform various functions under the control of one or more microprocessors or other control devices. Furthermore, those skilled in the art will understand that embodiments of the present disclosure can be practiced in conjunction with any number of mobility systems, and the vehicle system described herein is merely one exemplary embodiment of the present disclosure.

[0033] For the sake of brevity, this document may not describe in detail conventional techniques related to signal processing, data transmission, signaling, control, and other functional aspects of the system (and its various operating components). Furthermore, the connecting lines shown in the various figures included herein are intended to illustrate exemplary functional relationships and / or physical couplings between various elements. It should be noted that many alternative or additional functional relationships or physical connections may exist in the embodiments of this disclosure.

[0034] Generally, this disclosure describes systems and methods for initiating a DFCO request to achieve passive GPF regeneration. A preheating cycle is initiated to raise the temperature of the engine and GPF when certain criteria are met. Operating engine conditions (e.g., those that change engine operation) may be activated to aid preheating. As the temperature rises, it is determined whether preheating is complete. For example, preheating is considered complete when the GPF temperature is at a level sufficient to support effective passive regeneration. When the preheating is complete, a DFCO request is initiated to achieve passive regeneration. The GPF temperature is monitored to ensure it remains at a sufficiently high level for regeneration. When the particulate load of the GPF drops below a predetermined level, the DFCO request is terminated and passive regeneration is complete. To achieve regeneration, a DFCO request can be supplied to the engine controller and / or the hybrid system controller, which determines the timing and initiation of the DFCO cycle. Thus, the GPF is passively regenerated during normal driving cycles, which may include selecting engine operation but does not require active regeneration.

[0035] This disclosure provides a system and method for passively regenerating the GPF during normal driving cycles of a hybrid vehicle, thereby avoiding the need for active regeneration, at least for the first 4,000 km of vehicle operation and potentially for a much longer period. Vehicle coasting may be the desired time for passive regeneration. When the gasoline engine is the sole power unit in a non-hybrid arrangement, the engine remains connected to the drivetrain via the transmission during driving. In this arrangement, the engine's injectors can be shut off during coasting, where the engine operates as an air pump without fuel. During these DFCO conditions, the engine pumps air through the exhaust system, which passively burns off accumulated particulate matter along with the high temperatures in the GPF. With a hybrid arrangement, the gasoline engine can be disconnected from the drivetrain / transmission when not needed. For example, when the hybrid vehicle is coasting, the gasoline engine can be shut off, and the vehicle's momentum can be used to charge the hybrid system's battery. Because the gasoline engine is shut off, it cannot operate as an air pump. As a result, there may not be enough oxygen delivered to the GPF for regeneration. Therefore, in hybrid vehicles with a GPF, this disclosure provides a method and system for achieving passive regeneration during normal driving cycles, when the engine may otherwise be shut down and disconnected from the drivetrain.

[0036] Referring to FIG1, a vehicle 22 having a hybrid powertrain 24 according to an exemplary embodiment is shown. As described in more detail below, the vehicle 22 includes a control method for initiating passive GPF regeneration in response to parameters of the hybrid powertrain 24. In various embodiments, the vehicle 22 typically includes a body 26 having a plurality of wheels 28. The body 26 substantially surrounds other components of the vehicle 22. Each wheel 28 is rotatably coupled to the body 26 near a respective corner. The vehicle 22 can be any of a variety of different types of automobiles, such as a sedan, four-wheeled vehicle, truck, or sport utility vehicle (SUV), and can be two-wheel drive (i.e., rear-wheel drive or front-wheel drive), four-wheel drive, or all-wheel drive.

[0037] Vehicle 22 includes a control system 30, which may include any number of controllers for various systems and functions. The controllers may be independent, separate and communicatively coupled together, or integrated together. For the purposes of this disclosure, control system 30 includes a DFCO module 32, an engine control module 34, and a hybrid system control module 36. DFCO module 32, engine control module 34, and hybrid system control module 36 may be embodied in any number of individual controllers that cooperate to initiate and execute DFCP requests. For efficiency, DFCO module 32, engine control module 34, and hybrid system control module 36 will be described as part of a control system 30 embodied in a controller 40, which should be understood to embody one or more controllers.

[0038] In an exemplary embodiment, vehicle 22 is a hybrid electric vehicle, and hybrid powertrain 24 typically includes an engine system 42 (such as a gasoline direct injection engine system), at least one electric motor 44, an energy source (such as a battery pack 46), and a transmission system 48, all configured to drive wheels 28. As those skilled in the art will understand, the electric motor 44 may be associated with the transmission system 48 as an integral or separate coupling component. The transmission system 48 enables the engine system 42 and / or the electric motor 44 to be coupled to the wheels 28 individually or jointly via the drivetrain 50 of vehicle 22.

[0039] Engine system 42 typically includes multiple components and subsystems, including engine 52, intake system 54, fuel system 56, exhaust system 58, valve system 60, and ignition system 62. In this embodiment, engine 52 is an internal combustion engine, particularly a direct-injection gasoline engine. Intake system 54 delivers air 55 via throttle valve 64 and controls the mass flow rate of air to engine 52. Fuel system 56 delivers fuel to engine 52 via multiple injectors 66 and controls the timing and amount of fuel delivery. Valve system 60 includes multiple valves 68 to control the inflow and outflow of air / gas into engine 52. Ignition system 62 includes multiple spark plugs 70 that initiate combustion in engine 52.

[0040] Exhaust system 58 delivers combustion gases from engine 52 and includes aftertreatment devices such as a three-way catalytic converter 72 and a gas permeable powder (GPPF) 74. The aftertreatment devices can be arranged in any of several different configurations. For example, the GPF 74 may be downstream of the three-way catalytic converter 72 as shown, or upstream of it in other embodiments. In some embodiments, the GPF 74 may internally include a three-way catalyst with or without a separate three-way catalytic converter 72. The catalyst in the three-way catalytic converter 72 and / or the GPF 74 is configured to convert hydrocarbons, carbon monoxide, and nitrogen oxides into harmless elements or compounds. The GPF 74 captures particulate matter and includes an internal substrate 76. Exhaust system 58 directs exhaust gas 80 through the aftertreatment devices and exits through tailpipe 78.

[0041] As shown in Figure 1, the control system 30 includes a controller 40, which, for simplicity, may be referred to as the singular and typically includes a computer system. Generally, the controller 40 is configured to receive inputs from various sensors configured to generate signals proportional to various physical input parameters associated with the vehicle 22, the hybrid powertrain 24, their subsystems, and other relevant systems. It should be understood that the operation of the vehicle 22 and the hybrid powertrain 24 is closely related and overlaps.

[0042] In the depicted embodiment, controller 40 includes at least one processor 82 and a memory device 84, and is coupled to a storage device 86. Processor 82 performs the computational and control functions of controller 40 and may include any type of processor or multiple processors, a single integrated circuit (such as a microprocessor), or any suitable number of integrated circuit devices and / or circuit boards working together to perform the functions of a processing unit. During operation, processor 82 executes one or more programs 88 and may use data 90, each of which may be contained within storage device 86, and thus, processor 82 controls the general operation of controller 40 while performing the processes described herein (such as those further described below).

[0043] Memory device 84 can be any suitable type of memory. For example, memory device 84 can include volatile and non-volatile storage in the form of read-only memory, random access memory, and keep-alive memory, including persistent or non-volatile memory that can be used to store various operational variables when processor 82 is powered off. Memory device 84 can be implemented using any of a variety of known storage devices, such as programmable read-only memory, erasable PROM, electrically erasable PROM, flash memory, or any other electrical, magnetic, optical, or combined storage device capable of storing data, some of which represents executable instructions used by controller 40. In some embodiments, memory device 84 may be located on and / or co-located on the same computer chip as processor 82. In the depicted embodiments, memory device 84 may store one or more stored values ​​of the program 88 and data 90 described above, such as for short-term data access.

[0044] Storage device 86 stores data, such as long-term data access used in the autonomous operation of vehicle 22, hybrid powertrain 24, control system 30, and related systems. Storage device 86 can be any suitable type of storage device, including direct-access storage devices such as disk drives, flash memory systems, etc. In one exemplary embodiment, storage device 86 includes a source from which memory device 84 receives a program that performs one or more embodiments of one or more processes of this disclosure, such as the steps of processes (and any subprocesses thereof) further described below. In another exemplary embodiment, program 88 may be directly stored in memory device 84 and / or otherwise accessed by memory device 84.

[0045] Program 88 represents executable instructions used by the electronic controller 40 in processing information and controlling the hybrid powertrain 24, vehicle 22, and their systems / subsystems. Instructions may include one or more separate programs, each comprising an ordered list of executable instructions for implementing logical functions. When executed by processor 82, the instructions support the reception and processing of signals from various sensors, as well as the execution of logic, calculations, methods, and / or algorithms for automatically controlling the components and systems of the hybrid powertrain 24 and vehicle 22. Processor 82 may generate control signals based on logic, calculations, methods, and / or algorithms to automatically control various components and systems.

[0046] As will be understood, data storage device 86 may be part of controller 40, separate from controller 40, part of one or more other controllers, or part of multiple systems. Memory device 84 and storage device 86 work with processor 82 to access and use program 88 and data 90. Although components of control system 30 are depicted as part of the same system, it should be understood that in some embodiments, these features may include multiple systems. Additionally, in various embodiments, control system 30 may include all or part of various other vehicle equipment and systems, and / or may be coupled to various other vehicle equipment and systems.

[0047] The control system 30 controls the operation of the hybrid powertrain 24 to deliver the desired operational performance. Typically, the controller 40 uses available inputs to the control system 30, which contain parametric data (including inputs from various sensors, actuators, and systems identified herein), to efficiently manage various functions of the hybrid powertrain 24 and the vehicle 22. For example, based on data inputs, the controller 40 precisely calculates and controls the operation of the hybrid powertrain 24.

[0048] Sensors associated with control system 30 include, but are not limited to, ambient air temperature sensor 102, vehicle speed sensor 104, GPF temperature sensor 106, GPF load (ΔP) sensor 108, pedal (throttle valve) position sensor 110, crank (engine speed) sensor 112, coolant temperature sensor 114, and oil temperature sensor 116. The vehicle speed sensor, throttle valve position sensor 110, engine speed sensor 112, coolant temperature sensor 114, and oil temperature sensor 116 are schematically shown as part of a sensor suite 100 associated with hybrid powertrain 24, wherein they vary in their respective locations within hybrid powertrain 24 or its associated systems. Ambient air temperature sensor 102 provides control system 30 with a signal indicating the temperature of the outside air and can be configured to monitor the air 55 entering intake system 54. Vehicle speed sensor 104 provides a signal indicating the speed at which vehicle 22 is traveling and can be located near drivetrain 50 at one of various positions to indicate vehicle speed. GPF temperature sensor 106 provides a signal indicating the temperature within GPF 74. ΔP sensor 108 provides a signal representing the particulate load of GPF 74, such as by monitoring the pressure drop through it. Pedal position sensor 110 provides a signal representing the torque request on hybrid powertrain 24 and may monitor the position of the operator-controlled throttle pedal or another part of the throttle system. Engine speed sensor 112 provides a signal representing the rotational speed of engine 52, for example by monitoring the RPMs of its crankshaft. Coolant temperature sensor 114 provides a signal representing the temperature of engine 52 and may be located in its coolant system. Oil temperature sensor 116 may also be included to monitor the temperature of the oil in the crankcase of engine 52. It should be understood that the operation of hybrid powertrain 24 and vehicle 22 may involve many other sensors not described or shown herein. The various sensors provide signals and / or information related to parameter measurements to controller 40 for processing and for controlling hybrid powertrain 24 and / or vehicle 22 through its various actuators.

[0049] Actuators associated with control system 30 include, but are not limited to, a throttle valve 64, a fuel system 56 including injectors 66, a valve system 60 including valves 68, an ignition system 62 including spark plugs 70, and a motor 44. Throttle valve 64 controls the flow rate of mass air supplied to engine 52 through intake system 54. Injectors 66 control the fuel flow to engine 52 and may provide one injector for each cylinder of engine 52. Valve 68 controls the intake of air 55 into each cylinder of engine 52 and the exhaust from each cylinder of engine 52, wherein each cylinder of engine 52 has multiple valves. Spark plugs 70 control the timing of combustion initiation in the individual cylinders of engine 52. Motor 44 provides torque when propelling vehicle 22 together with or separately from engine 52. It should be understood that the operation of hybrid powertrain 24 and vehicle 22 may involve many other actuators not described or shown herein.

[0050] Referring to Figure 2, DFCO activation and GPF regeneration are depicted as a series of high-level states via DFCO model 200. DFCO model 200 typically includes GPF / DFCO evaluation 202, DFCO preheating 204, DFCO preheating completion 206, DFCO activation 208, and DFCO execution 210. Processing DFCO model 200 involves moving through the first three states (GPF / DFCO evaluation 202, DFCO preheating 204, DFCO preheating completion 206) under specific entry and exit conditions, after which GPF 74 is ready for regeneration in the fourth state. At the point of DFCO activation 208, DFCO model 200 requests DFCO, such as for execution by the hybrid system control module 36 and / or engine control module 34. DFCO model 200 uses specific calibrated engine operating conditions to achieve cyclic regeneration of GPF 74, thereby avoiding the influence of undesirable Ki factors. GPF / DFCO evaluation 202 determines whether GPF 74 is ready for regeneration and whether other parameters support DFCO. DFCO preheating prepares GPF 74 for regeneration. In the DFCO preheating completion state 206, GPF 74 is heated for regeneration. In the DFCO activation state 208, control system 30 initiates a DFCO request. In the DFCO execution state 210, control system 30 executes DFCO, such as via hybrid control module 36 and / or engine control module 34, to regenerate GPF 74 at the first available opportunity.

[0051] The sensors and actuators shown in Figure 1 are used to determine the timing and initiation of the DFCO request, and to implement the resulting DFCO when appropriate to achieve passive regeneration of the GPF 74. Referring to Figure 3 simultaneously with Figure 4, the control system 30 and its operation, or a portion thereof, may be embodied in a control structure 300, typically representing the DFCO module 32, and in process 400. Structure 300 may include multiple modules / sub-modules for executing process 400 to provide useful information to the controller 40 for controlling the hybrid powertrain 24, including the exhaust system 58, which may be accomplished as part of the control of the vehicle 22. In various embodiments, control structure 300 typically includes a GPF evaluation module 302, a DFCO evaluation module 304, a DFCO preheating module 306, a DFCO execution module 308, and a data storage 310, which may typically represent a storage device 88.

[0052] Control structure 300 may include any number of additional modules to control aspects of the hybrid powertrain 24, vehicle 22, and / or other systems independently of or in coordination with modules of control structure 300. For example, a module (not shown) that determines whether to operate engine 52 or motor 44 can use calculations and outputs of control structure 300 at any given time to determine the appropriate torque input device. During operation of vehicle 22, GPF evaluation module 302 determines, after start 401 of process 400, whether the particulate load of substrate 76 in GPF 74 is above a threshold. For example, condition determination 402 is met when ΔP sensor 108 delivers a signal 312 to GPF evaluation module 302 that the pressure drop on GPF 74 is above a threshold pressure, where the threshold pressure can be obtained from data storage 310 and indicates that GPF 74 needs to be regenerated. When determination 402 is negative and GPF 74 does not need to be regenerated, process 400 returns to start 401.

[0053] The particulate load of the GPF 74 can be determined by a load monitor 402, for example, by using data from the ΔP sensor 108, such as by comparing input data with data in a data storage 310, which can be stored in a retrievable format, such as in a lookup table with various values ​​associated with various conditions. In other embodiments, a particulate load model can be developed and stored in the data storage 310 as at least part of the load monitor, to supplement determination 402, or for independent determination 402. This model can be an algorithm, such as one developed using characteristic testing and / or computational modeling software, to indicate the current particulate load of the GPF 74 based on past operation of the hybrid powertrain 24. This model can use inputs from the coolant temperature sensor 114, engine speed sensor 112, ambient temperature sensor 102, and / or oil temperature sensor 116. In embodiments where the model is used solely as a load monitor to indicate particulate load, the ΔP sensor 108 can be omitted. The model can be executed by the GPF evaluation module 302 using inputs from the coolant temperature sensor 114, engine speed sensor 112, ambient temperature sensor 102, and / or oil temperature sensor 116, along with algorithms and other data such as from the data storage 310, to predict the particulate load of the GPF 74. In summary, a determination 402 can be made using a load monitor based on data from the ΔP sensor 108, and in some embodiments, this determination can be confirmed or replaced by the model's results.

[0054] After confirming 402, the GPF evaluation module 302 signals the DFCO evaluation module 304, and process 400 continues, such as by the DFCO evaluation module 304 determining 403 whether there is any active fault in the GPF temperature sensor 106 or ΔP sensor 108. Any active fault may be indicated by data stored in the data storage 310, or otherwise received from other parts of the controller 40 via signal 314. An active fault indicates that the sensor reading may be unreliable, and process 400 will return and not continue until all active faults are no longer present, cleared, or corrected. When no active fault is present, process 400 continues, such as by the DFCO evaluation module 304 using signal 316 from the vehicle speed sensor 104 to determine 404 whether the speed of vehicle 22 is higher than the calibration speed, which can be retrieved from the data storage 310. The calibration speed is the minimum speed at which the deceleration of vehicle 22 will effectively / feasibly regenerate the GPF 74 during fuel cut-off and deceleration. When the speed of vehicle 22 is not higher than the calibration speed, it means that determination 404 is negative, process 400 returns and will only continue when the speed of vehicle 22 is higher than the calibration speed.

[0055] When the vehicle 22's speed exceeds the calibration speed, process 400 continues to determine 410 whether the temperature of GPF 74 is above the calibration temperature. For example, DFCO evaluation module 304 uses signal 318 from GPF temperature sensor 106 to determine whether GPF 74 is at the lowest temperature that can be retrieved from data storage 310, enabling GPF 74 to be regenerated after a preheating period. In other words, considering the additional preheating phase to be performed by process 400, the lowest temperature is a temperature above which GPF 75 regeneration is feasible. When the temperature of GPF 74 is not above the calibration temperature, meaning determination 410 is negative, process 400 returns and will only proceed if the temperature of GPF 74 is above the calibration temperature. For example, when the temperature of GPF 74 is at or near ambient temperature, process 400 does not proceed.

[0056] When the temperature of GPF 74 is higher than the calibration temperature, process 400 continues into DFCO preheating routines 406-410. For example, DFCO preheating module 306 can initiate DFCO preheating of engine 52, and thus DFCO preheating of GPF 74. Typically, DFCO preheating routines 406-410, such as those executed by DFCO preheating module 306, monitor the temperature of GPF 74 via signal 318 from GPF temperature sensor 106, deliver an output to engine 52 / engine control module 34 via signal 320, and reference inputs from data storage 310.

[0057] At entry 406 of the DFCO preheating routine, it is determined that 402-405 all lead to positive results and their conditions have been met. Entry 406 initiates or continues the operation of engine 52, such as via signal 320 to engine 52 / engine control module 34. As prompted by signal 320 via DFCO preheating module 306, engine 52 undergoes preheating control 407 to operate in an accelerated preheating mode / state. For example, signal 320 may cause a change in the air / fuel ratio (equivalent ratio, EQR) of operating engine 52 to increase the heat generated during combustion. For example, the position of throttle valve 64 and / or the fuel supplied by injector 66 may be set such that the engine operates under non-stoichiometric conditions to accelerate preheating. In another example, fuel system 56 may be operated to deliver fractional injections of fuel via injector 66. In the case of fractional injection, instead of using a single injection profile of injector 66, two or more injection pulses are delivered with a delayed pause between pulses. In another example, the timing of the spark delivered by spark plug 70 can be targeted to increase the combustion temperature. In another example, the phase angle can be changed to alter the opening and closing of valve 68, thereby increasing the exhaust temperature. The DFCO preheating module 306 can employ any combination of EQR, fractional injection, spark timing, and / or phase angle modification to achieve the desired preheating of GPF 74 during preheating control 407. Feedback is monitored from GPF temperature sensor 106, and it is determined 408 whether GPF 74 is at or above a threshold temperature sufficient to achieve regeneration. When the determination 408 is negative, preheating control 407 continues. When the determination is positive, meaning the temperature of GPF 74 is above the threshold, process 400 continues to 409 DFCO preheating completion mode / state. At DFCO preheating completion entry 409, the temperature of GPF 74 is high enough to feasiblely achieve GPF 74 regeneration under DFCO.

[0058] Process 400 continues to monitor the temperature of GPF 74 and again determines 410 whether GPF 74 is at or above a threshold temperature sufficient to achieve regeneration. When determination 408 is negative, preheating control 407 continues. When determination is positive, meaning the temperature of GPF 74 is above the threshold, process 400 proceeds to DFCO activation 411. For example, DFCO preheating module 306 signals DFCO execution module 308 (such as a submodule of DFCO module 32), DFCO execution module 308 sends a DFCO request signal 322 to engine control module 34 and / or a signal 324 to hybrid control module 36 indicating that DFCO is enabled and can be initiated at the first available opportunity. For example, when the driver of vehicle 22 lifts their foot off the accelerator (e.g., sensed by pedal position sensor 110) and DFCO execution module 308 has already enabled DFCO via signals 322, 324, signal 324 to engine control module 34 and / or to hybrid control module 36 can initiate DFCO.

[0059] DFCO can be implemented based on the parameters described above, and the engine control module 34 can shut off the injector 66, thereby stopping the flow of fuel to the cylinders of engine 52. As a result, engine 52 rotates without ignition and operates as an air pump. Pumping air 55 into the high-temperature GPF 74 (as warmed in this context) spontaneously causes the burning of particulate matter accumulated in GPF 74 and delivers passive regeneration during normal driving cycles of vehicle 22, such as when vehicle 22 coasts and decelerates, where engine 52 is connected to drivetrain 50 via transmission system 48.

[0060] Pedal position sensor 110 sends a signal indicating a torque request on hybrid powertrain 24. While engine 52 can prepare for DFCO after warm-up, hybrid control module 36 assesses torque control and ultimately determines whether to maintain engine 52 operation and whether the torque request supports DFCO initiation. When the torque command is sufficiently low and vehicle 22 operation supports DFCO, such as during coasting, DFCO is initiated, and process 400 continues to regenerate GPF 74. Process 400 determines 412 whether the particulate load on GPF 74 has dropped below the regeneration level (meaning GPF 74 is being regenerated) and whether GPF 74 is below a threshold temperature (indicating burnout completion). DFCO execution module 308 monitors ΔP sensor 108 and GPF temperature sensor 106, and is therefore also supplied with signals 312 and 318. DFCO execution module 308 compares the received values ​​in signals 312 and 318 with thresholds retrieved from data storage 310 to make determination 412. When at least one of determinations 412 is negative, process 400 continues in DFC0 enable 411. When both determinations 412 are positive, regeneration is complete, and process 400 ends and prepares for restart / start 401.

[0061] Therefore, the systems and methods provide a mechanism for passively regenerating the GPF without requiring an active regeneration cycle, at least during the first 4000 km of vehicle operation, and when passive regeneration opportunities may otherwise be unavailable due to the hybrid powertrain arrangement. One example involves a strong hybrid application where deceleration fuel cutoff during the cycle may not otherwise occur, and is initiated, as described herein, for example, by operating the engine while the hybrid controller would otherwise only operate the vehicle's electric motor. The state of the GPF (i.e., particulate load) determines the need to initiate a DFCO (Deceleration-Driven Operation). Executing a DFCO means rotating the engine as an air pump without fuel to supply oxygen to the GPF to burn off soot / particulate matter. The described systems and methods create opportunities under specific calibrated engine operating conditions, allowing for cyclic regeneration of the GPF to avoid potential Ki-factor vehicle certification impacts.

[0062] While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be understood that numerous variations exist. It should also be understood that the one or more exemplary embodiments are merely examples and are not intended to limit the scope, applicability, or configuration of this disclosure in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient roadmap for implementing one or more exemplary embodiments. It should be understood that various changes can be made to the function and arrangement of the elements without departing from the scope of this disclosure as set forth in the appended claims and their legal equivalents.

Claims

1. A powertrain system for regenerating a gas particulate filter, the powertrain system comprising: An exhaust system, the exhaust system including the gas particulate filter, the gas particulate filter being configured to collect particulate matter from the exhaust flow of the powertrain system; A temperature sensor configured to monitor the temperature of the gas particulate filter; A load monitor configured to provide a load input indicating the particulate load of the gas particulate filter; and at least one controller configured to: determine whether the gas particulate filter needs regeneration by comparing the load input with a stored, predetermined value indicating that the gas particulate filter needs regeneration; determine whether the temperature of the gas particulate filter is higher than a calibration temperature; preheat the gas particulate filter when the gas particulate filter needs regeneration based on the comparison of the load input with the stored value, and when the temperature of the gas particulate filter is higher than the calibration temperature, wherein after preheating, the calibration temperature is above a level at which regeneration of the gas particulate filter is effective; and after preheating, initiate the regeneration when a value received from the temperature sensor meets a minimum threshold level, wherein the minimum threshold level is a level at which regeneration of the gas particulate filter is effective after preheating.

2. The powertrain system of claim 1, further comprising a gasoline engine, wherein the at least one controller is configured to stop fuel flow to the gasoline engine via at least one actuator, wherein the gasoline engine is configured to operate as a fuel-free air pump under deceleration fuel cut-off conditions during the regeneration process.

3. The powertrain system according to claim 1, wherein, Before initiating the regeneration, the at least one controller is configured to: determine whether a sensor fault is active, including for the temperature sensor and for the load monitor; and determine whether the temperature of the gas particulate filter is higher than the calibration temperature, at which regeneration of the gas particulate filter is feasible.

4. The powertrain system according to claim 1, wherein, Before initiating the regeneration, the at least one controller is configured to determine whether the speed of the vehicle equipped with the powertrain system is higher than the minimum speed at which the deceleration of the vehicle would cause the gas particulate filter to regenerate.

5. The powertrain system of claim 1, further comprising an engine in the powertrain system, a throttle valve for controlling air supplied to the engine, and at least one injector for controlling fuel supplied to the engine, wherein the at least one controller is configured to initiate operation of the engine to accelerate preheating of the particulate filter by changing the air / fuel ratio supplied to the engine through operation of the throttle valve and operation of the at least one injector, wherein the at least one controller is configured to stop fuel flow to the engine via at least one actuator after preheating, and the engine is configured to operate as a fuelless air pump under deceleration fuel cut-off conditions when regeneration is performed.

6. The powertrain system of claim 1, further comprising an engine in the powertrain system, and at least one injector for controlling the supply of fuel to the engine, wherein the at least one controller is configured to initiate operation of the engine to accelerate the preheating of the gas particulate filter by supplying fractional injections via the at least one injector.

7. The powertrain system according to claim 1, further comprising: The internal combustion engine in the powertrain system; The electric motor in the powertrain system; And a transmission system in the powertrain system for connecting and disconnecting the internal combustion engine from the drivetrain, wherein the at least one controller is configured to connect the internal combustion engine to the drivetrain via the transmission system during the regeneration of the gas particulate filter.

8. A method for regenerating a gas particulate filter in a powertrain system by decelerating fuel cut-off, the method comprising: Particulate matter is collected from the exhaust flow of the powertrain system via a gas particulate filter; the temperature of the gas particulate filter is monitored by a temperature sensor; A load input of the particulate load of the gas particulate filter is provided by a load monitor; at least one controller determines whether the gas particulate filter needs regeneration by comparing the load input with a stored value, wherein the stored value is predetermined and indicates that regeneration of the gas particulate filter is required; it is determined whether the temperature of the gas particulate filter is higher than a calibration temperature; when the determination based on the comparison of the load input and the stored value indicates that the gas particulate filter needs regeneration, and when the temperature of the gas particulate filter is higher than the calibration temperature, the at least one controller performs preheating of the gas particulate filter, wherein after preheating, the calibration temperature is above a level at which regeneration of the gas particulate filter is effective; and after preheating, when the value received from the temperature sensor meets a minimum threshold level, the at least one controller initiates the regeneration, wherein the minimum threshold level is a level at which regeneration of the gas particulate filter is effective after preheating.

9. The method according to claim 8, further comprising: The flow of fuel to the gasoline engine is stopped by the at least one controller via at least one actuator; When the regeneration is performed, under deceleration fuel cut-off conditions, the gasoline engine is operated as a fuelless air pump by the at least one controller.

10. The method of claim 8, further comprising: An internal combustion engine is provided in the powertrain system; An electric motor is provided in the powertrain system; The powertrain system provides a transmission system for engaging and disengaging the internal combustion engine from the drivetrain; and during regeneration of the gas particulate filter, the internal combustion engine is engaged with the drivetrain via the transmission system by the at least one controller; during regeneration, the fuel supply to the internal combustion engine is cut off by at least one actuator; And determine whether the speed of the vehicle in which the powertrain system is installed is higher than the calibration speed, wherein the calibration speed is the minimum speed at which the deceleration of the vehicle during the period of cutting off the fuel supply to the internal combustion engine and during the deceleration of the vehicle while the internal combustion engine is running will cause the gas particulate filter to regenerate.

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