Adjusting heat management mode entry and exit temperature thresholds based on post-processing system aging

Abstract

A system includes an exhaust aftertreatment system coupled to an engine and a controller including at least one processor coupled to at least one memory device storing instructions that, when executed by the at least one processor, cause the controller to perform certain operations. The operations include estimating an age of the exhaust aftertreatment system and adjusting at least one of an entry temperature threshold or an exit temperature threshold for a thermal management mode of the exhaust aftertreatment system based on the age of the exhaust aftertreatment system.

Description

[0001] Cross-reference of related applications

[0002] This application claims the benefit and priority of U.S. Provisional Patent Application No. 63 / 123151, filed December 9, 2020, which is incorporated herein by reference in its entirety. Technical Field

[0003] This disclosure relates to controlling the thermal management mode for an engine exhaust aftertreatment system by actively adjusting the entry and exit temperature thresholds of the thermal management mode based on the aging of the aftertreatment system.

[0004] background

[0005] Many engines are coupled to exhaust aftertreatment systems that reduce harmful emissions such as nitrogen oxides (NOx), sulfur oxides, particulate matter, etc. For example, a reducing agent can be injected into the exhaust stream to chemically bind with particles in the exhaust. This mixture interacts with a selective catalytic reduction (SCR) catalyst, which initiates a reaction in the mixture at a certain temperature, converting harmful NOx particles into pure nitrogen and water. Over time, aftertreatment systems age, which can cause the system to lose its effectiveness (e.g., a reduced ability to convert NOx into less harmful elements).

[0006] Overview

[0007] One embodiment relates to a system. The system includes an exhaust aftertreatment system coupled to an engine and a controller including at least one processor coupled to at least one memory device storing instructions that, when executed by the at least one processor, cause the controller to perform certain operations. The operations include: estimating the aging of the exhaust aftertreatment system, and adjusting at least one of an entry temperature threshold or an exit temperature threshold for a thermal management mode of the exhaust aftertreatment system based on the aging of the exhaust aftertreatment system.

[0008] In some embodiments, the operation further includes: determining the airspeed through the exhaust aftertreatment system, wherein at least one of the entry temperature threshold or the exit temperature threshold of the thermal management mode of the exhaust aftertreatment system is adjusted based on the airspeed and the aging of the exhaust aftertreatment system.

[0009] In some embodiments, the operation further includes: adjusting at least one of the entry temperature threshold or the exit temperature threshold using a lookup table based on a predefined amount, based on the determined airspeed and the aging of the exhaust aftertreatment system.

[0010] In some embodiments, the airspeed is determined using the exhaust flow rate and the dimensions of the exhaust aftertreatment system.

[0011] In some embodiments, the operation further includes: determining the system output NOx amount; comparing the system output NOx amount with a desired system output NOx amount; and adjusting at least one of the entry temperature threshold or the exit temperature threshold based on the comparison.

[0012] In some embodiments, the thermal management mode includes commands for at least one of the following: cylinder deactivation mode, increased fuel supply, post-injection, change of injection timing, activation of the electric heater in the exhaust aftertreatment system, increase of power output from the engine, actuation of the turbocharger, or change of the position of the intake throttle valve.

[0013] In some embodiments, estimating the aging of the exhaust aftertreatment system includes:

[0014] The aging of the selective catalytic reduction catalyst in a selective catalytic reduction system is estimated based on at least one of the following: (i) time equivalent at a reference temperature, (ii) sulfur content determination, or (iii) the ratio of ammonia to nitrogen oxides.

[0015] The aging condition of the diesel engine oxidation catalyst is estimated based on at least one of (i) the time equivalent at the reference temperature or (ii) the sulfur content determination; and

[0016] The aging of the exhaust aftertreatment system is estimated based on at least one of the aging of the selective catalytic reduction catalyst or the aging of the diesel engine oxidation catalyst.

[0017] Another embodiment relates to a system. The system includes a controller comprising at least one processor and at least one memory device coupled to the at least one processor, the at least one memory device storing instructions therein that, when executed by the at least one processor, cause the controller to perform operations. The operations include: estimating the aging of an exhaust aftertreatment system coupled to an engine; and adjusting at least one of an entry temperature threshold or an exit temperature threshold for a thermal management mode of the exhaust aftertreatment system based on the estimated aging of the exhaust aftertreatment system.

[0018] In some embodiments, the operation further includes: determining the airspeed through the exhaust aftertreatment system, wherein at least one of the entry temperature threshold or the exit temperature threshold of the thermal management mode of the exhaust aftertreatment system is adjusted based on the airspeed and the aging status of the exhaust aftertreatment system.

[0019] In some embodiments, the operation further includes: adjusting at least one of the entry temperature threshold or the exit temperature threshold using a lookup table based on a predefined amount, based on the determined airspeed and the aging status of the exhaust aftertreatment system.

[0020] In some embodiments, the airspeed is determined using the exhaust flow rate and the dimensions of the exhaust aftertreatment system.

[0021] In some embodiments, the operation further includes: determining the system output NOx conversion amount; comparing the system output NOx conversion amount with a desired system output NOx conversion amount; and adjusting at least one of the entry temperature threshold or the exit temperature threshold based on the comparison.

[0022] In some embodiments, the thermal management mode includes commands for at least one of the following: cylinder deactivation mode, increased fuel supply, post-injection, change of injection timing, activation of the electric heater in the exhaust aftertreatment system, increase of power output from the engine, actuation of the turbocharger, actuation of the intake bypass valve, actuation of the exhaust bypass valve, actuation of the EGR bypass valve, or change of the position of the intake throttle valve.

[0023] In some embodiments, estimating the aging of the exhaust aftertreatment system includes:

[0024] The selective catalytic reduction catalyst aging condition of the selective catalytic reduction system is estimated based on at least one of the following: (i) time equivalent at a reference temperature, (ii) sulfur content determination, (iii) ammonia to nitrogen oxide ratio, (iv) duty cycle, or (v) count and duration of active and passive regeneration events.

[0025] The aging condition of the diesel engine oxidation catalyst is estimated based on at least one of (i) the time equivalent at the reference temperature or (ii) the sulfur content determination; and

[0026] The aging of the exhaust aftertreatment system is estimated based on at least one of the aging of the selective catalytic reduction catalyst or the aging of the diesel engine oxidation catalyst.

[0027] Another embodiment relates to a method. The method includes: estimating the aging of an exhaust aftertreatment system coupled to an engine, and adjusting at least one of an entry temperature threshold or an exit temperature threshold for a thermal management mode of the exhaust aftertreatment system based on the aging of the exhaust aftertreatment system.

[0028] In some embodiments, the method further includes: determining the airspeed through the exhaust aftertreatment system; and, based on the determined airspeed and the aging status of the exhaust aftertreatment system, using a lookup table to adjust at least one of the entry temperature threshold or the exit temperature threshold based on a predefined amount.

[0029] In some embodiments, the airspeed is determined using the exhaust flow rate and the dimensions of the exhaust aftertreatment system.

[0030] In some embodiments, the method further includes: determining the system output NOx conversion amount; comparing the system output NOx conversion amount with a desired system output NOx conversion amount; and adjusting at least one of the entry temperature threshold or the exit temperature threshold based on the comparison.

[0031] In some embodiments, the thermal management mode includes commands for at least one of the following: cylinder deactivation mode, increased fuel supply, post-injection, change of injection timing, activation of the electric heater in the exhaust aftertreatment system, increase of power output from the engine, actuation of the turbocharger, actuation of the intake bypass valve, actuation of the exhaust bypass valve, actuation of the EGR bypass valve, or change of the position of the intake throttle valve.

[0032] In some embodiments, estimating the aging status of the exhaust aftertreatment system includes:

[0033] The selective catalytic reduction catalyst aging condition of the selective catalytic reduction system is estimated based on at least one of the following: (i) time equivalent at a reference temperature, (ii) sulfur content determination, (iii) ammonia to nitrogen oxide ratio, (iv) duty cycle determination based on at least one of driving distance, fuel burned, average speed over time, or load, or (v) count and duration of active or passive regeneration events.

[0034] The aging condition of a diesel engine oxidation catalyst is estimated based on at least one of the following: (i) the time equivalent at the reference temperature, (ii) the sulfur content determination, (iii) the ammonia to nitrogen oxide ratio, (iv) the duty cycle, or (v) the count and duration of active or passive regeneration events; and

[0035] The aging of the exhaust aftertreatment system is estimated based on at least one of the aging of the selective catalytic reduction catalyst or the aging of the diesel engine oxidation catalyst.

[0036] This overview is illustrative only and is not intended to be limiting in any way. Other aspects, features, and advantages of the apparatus or process described herein will become apparent from the detailed description set forth herein in conjunction with the accompanying drawings, wherein like reference numerals refer to like elements.

[0037] Numerous specific details are provided to give a thorough understanding of embodiments of the subject matter of this disclosure. In one or more embodiments and / or implementations, the described features of the subject matter of this disclosure may be combined in any suitable manner. In this respect, one or more features of one aspect of the invention may be combined with one or more features of different aspects of the invention. Furthermore, additional features that may not be present in all embodiments or implementations may be recognized in some embodiments and / or implementations. Brief description of the attached diagram

[0039] Figure 1 This is a schematic diagram of a transportation system according to an exemplary embodiment.

[0040] Figure 2 This is according to an exemplary embodiment. Figure 1 Block diagram of the controller.

[0041] Figure 3 According to the exemplary embodiments, for Figures 1-2 The flowchart of the controller logic.

[0042] Figure 4 According to the exemplary embodiments, for Figures 1-2 The flowchart of the controller logic.

[0043] Figure 5 According to the exemplary embodiments, for Figures 1-2 The flowchart of the controller logic.

[0044] Detailed description

[0045] The following is a more detailed description of various concepts and implementations related to methods, apparatuses, and systems for actively adjusting entry and exit thresholds for thermal management based on post-processing system aging. Before turning to the accompanying drawings, which illustrate certain exemplary embodiments in detail, it should be understood that this disclosure is not limited to the details or methods set forth in the specification or shown in the drawings. It should also be understood that the terminology used herein is for descriptive purposes only and should not be considered limiting.

[0046] Exhaust aftertreatment systems can utilize thermal management operating modes. A “thermal management mode” refers to operating a system, such as an engine, exhaust aftertreatment system, or its components, to actively increase the temperature of the exhaust aftertreatment system. During a thermal management mode, the controller can change from a set of operating parameters primarily optimized for fuel economy (e.g., parameters controlling engine operation, which may include, for example, a fuel curve) to a set primarily optimized for providing higher temperatures for the aftertreatment. As an example, and during a thermal management mode, the controller can provide commands to increase exhaust temperature to raise the temperature of one or more components in the exhaust aftertreatment system (e.g., by increasing engine power output, implementing cylinder deactivation mode, etc.). Cylinder deactivation (CDA) mode is a broad term encompassing various related but distinct cylinder deactivation operating modes. The first type of CDA operating mode is called “fixed cylinder CDA.” In a fixed cylinder CDA operating mode, the same cylinder is in an active / inactive state for each engine cycle during the fixed cylinder CDA operating mode. The second type of CDA operating mode is called “skip ignition” or “dynamic skip ignition” operating mode. In a skip-ignition CDA mode, one or more cylinders are deactivated / inactive (e.g., no combustion occurs) on a cycle-by-cycle basis. Thus, a cylinder may be inactive in a first engine cycle and active in a second engine cycle. An "active" cylinder means that combustion is permitted in that cylinder. An "inactive" or "deactivated" cylinder means that combustion is not permitted in that cylinder. This disclosure applies to every type of CDA operating mode, and the term CDA mode means to include all such operating modes unless otherwise indicated. Additionally, as another example, a thermal management mode may include increasing the temperature via a controller command specifying a feature (e.g., an electric heater activated to heat components of the exhaust or aftertreatment system).

[0047] As described herein, various embodiments disclose systems, methods, and apparatuses for actively adjusting and applying thermal management modes to an engine aftertreatment system based on exhaust aftertreatment system aging, including entry and exit temperature thresholds. The entry and exit thresholds determine when the system enters and exits a thermal management mode, respectively. The entry and exit thresholds refer to entry and exit temperatures. In this respect, a thermal management mode can be implemented / activated to raise the aftertreatment system temperature when the temperature is below a predefined threshold (entry threshold), and then deactivated to facilitate normal operation once the temperature exceeds the predefined threshold (exit threshold). These thresholds are typically static and unadjusted. In this respect, these temperature thresholds are typically set at the manufacturing date or at the beginning of the product's market launch and remain unchanged throughout the product's lifespan. However, without adjusting the thresholds, the SCR ages over time, and the conversion efficiency of nitrogen oxides (NOx) decreases. Therefore, over time (e.g., as the vehicle travels more mileage), the system's NOx output may begin to increase. The performance at the end of the lifespan may match a much higher system NOx output compared to the beginning of the lifespan. This performance degradation may further lead to non-compliance with various regulations (e.g., CARB, EPA, or other environmental regulations). According to this disclosure, the controller estimates the aging condition of the aftertreatment system or its components based on one or more parameters and adjusts the entry and exit thresholds of the thermal management mode temperature based on the determined aging condition. The determination or estimation of the aging condition (also referred to as aging status or aging condition) can be based on several factors, such as system start-up time, mileage, duty cycle value, the amount of time spent exceeding the temperature threshold, and the number of active regeneration events. After determining the aftertreatment aging condition, the entry and exit thresholds of the aftertreatment thermal management mode are adjusted to manage system output emissions (e.g., NOx emissions, such as system output NOx conversion values) and contribute to the efficiency of the aftertreatment system and to maintain the lifespan of the aftertreatment system.

[0048] Now for reference Figure 1The diagram illustrates a system 100 according to an exemplary embodiment. System 100 includes an engine 101, an aftertreatment system 120 coupled to the engine 101, an operator I / O device 130, a controller 140, and a telematics unit 150, wherein the controller 140 is communicatively coupled to each of the foregoing components. The telematics unit 150 facilitates the acquisition and transmission of data acquired regarding the operation of system 100. According to one embodiment, system 100 is embodied in a vehicle. In various alternative embodiments, system 100 may be implemented in a non-vehicle application (e.g., a generator or generator set). In the illustrated example, system 100 is embodied in a vehicle. The vehicle may be an on-road or off-road vehicle, including but not limited to long-haul trucks, medium-haul trucks (e.g., pickup trucks), cars, sports cars, tanks, aircraft, boats, and any other type of vehicle utilizing an exhaust aftertreatment system.

[0049] In the illustrated example, engine 101 is configured as a compression ignition internal combustion engine utilizing diesel fuel. However, in various alternative embodiments, engine 101 may be configured as another type of engine (e.g., spark ignition) utilizing another type of fuel (e.g., gasoline, natural gas, biodiesel). In other exemplary embodiments, engine 101 may be or include an electric motor (e.g., a hybrid powertrain). Engine 101 includes one or more cylinders and associated pistons. Atmospheric air combines with fuel and burns to power engine 101. Combustion of fuel and air in the compression chamber of engine 101 produces exhaust gas, which is operatively discharged to an exhaust manifold and aftertreatment system 120. Engine 101 may be coupled to a turbocharger (not shown). A turbocharger (e.g., a variable geometry turbocharger) includes a compressor coupled to an exhaust turbine via a connector shaft. Typically, hot exhaust gas rotates the turbine, which in turn rotates the shaft, which in turn rotates the compressor, which draws in air. By compressing the air, more air can enter the cylinders or combustion chamber, thereby burning more fuel and increasing power and efficiency. A heat exchanger (such as a turbocharger air cooler) can be used to cool the compressed air before it enters the cylinder. In some embodiments, the turbocharger is omitted.

[0050] According to an exemplary embodiment, a post-processing system 120 is shown. It should be understood that... Figure 1 The schematic diagram depicted is merely one implementation of the exhaust gas aftertreatment system. Many different configurations can be achieved using the systems and methods described herein.

[0051] Aftertreatment system 120 is configured to treat exhaust gas from engine 101, which enters the aftertreatment system 120 via an exhaust pipe, in order to reduce emissions of harmful or potentially harmful elements (e.g., NOx emissions, particulate matter, SOx, greenhouse gases, CO, etc.). Aftertreatment system 120 may include various components and systems such as a diesel engine oxidation catalyst (DOC) 121, a diesel engine particulate filter (DPF) 122, and a selective catalytic reduction (SCR) system 123. SCR system 123 converts nitrogen oxides present in the exhaust gas produced by engine 101 into diatomic nitrogen and water through oxidation within the catalyst. DPF 122 is configured to remove particulate matter, such as soot, from the exhaust gas flowing in the exhaust duct system. In some embodiments, DPF 122 may be omitted. Furthermore, the spatial order of the catalyst elements may differ.

[0052] The operation of an SCR catalyst can be affected by several factors. For example, the effectiveness of an SCR catalyst in reducing NOx in exhaust gases is affected by operating temperature. If the SCR catalyst temperature is below a threshold or range, its effectiveness in reducing NOx may decrease below the desired threshold level, increasing the risk of high NOx emissions into the environment. SCR catalyst temperatures may fall below the threshold temperature under several conditions, such as during and immediately after engine start-up, and during cold ambient conditions. In operation, typically higher combustion temperatures promote the production of engine output NOx (EONOx). This is due to rapid flame expansion within the cylinder, which leads to NOx release. Increasing exhaust gas recirculation (EGR) lowers the combustion temperature, thus reducing EONOx. However, EGR promotes particulate emissions due to incomplete combustion of particulate matter. Additionally, higher loads and power demands tend to increase combustion temperatures, thereby increasing EONOx. Higher power output corresponds to higher fuel pressure and quantity (increased fuel rail pressure). Therefore, increasing fuel pressure and quantity also tends to promote EONOx production. The effectiveness of SCR catalysts can also be affected by malfunctions in the SCR system, such as a lack of reductant, build-up on the SCR catalyst, and consistently low conversion efficiencies (e.g., NOx conversion efficiency).

[0053] The aftertreatment system 120 may also include a reducing agent delivery system, which may include a decomposition chamber (e.g., a decomposition reactor, reaction tube, decomposition pipeline, reaction conduit, etc.) to deliver a reducing agent (e.g., urea, diesel exhaust fluid (DEF)). Urea aqueous solution (UWS), aqueous urea solution, etc., are converted into ammonia. Diesel exhaust fluid (DEF) 124 is added to the exhaust stream to aid catalytic reduction. The reducing agent can be injected via an injector upstream of the SCR catalytic converter component, allowing the SCR catalytic converter component to receive the mixture of reducing agent and exhaust gas. The reducing agent droplets undergo evaporation, pyrolysis, and hydrolysis processes to generate non-NOx compounds within the decomposition chamber, SCR catalytic converter component, and / or exhaust duct system. x Emissions (such as gaseous ammonia), non-NO x Emissions exit aftertreatment system 120. Aftertreatment system 120 may also include an oxidation catalyst (e.g., DOC 121) fluidly coupled to an exhaust duct system to oxidize hydrocarbons and carbon monoxide in the exhaust. To properly aid this reduction, DOC 121 may need to be at a specific operating temperature. In some embodiments, this specific operating temperature is between 200°C and 500°C. In other embodiments, this specific operating temperature is the temperature at which the conversion efficiency of DOC 121 (e.g., the conversion of NOx to less harmful compounds, referred to as NOx conversion efficiency) exceeds a predefined threshold.

[0054] As shown, multiple sensors 125 are included in the aftertreatment system 120. The number, placement, and type of sensors included in the aftertreatment system 120 are shown for illustrative purposes only. In other configurations, the number, placement, and type of sensors may differ. Sensors 125 may be NOx sensors, temperature sensors, particulate matter (PM) sensors, flow rate sensors, other emission component sensors, pressure sensors, some combination thereof, etc. NOx sensors are configured to acquire data (e.g., concentration, such as parts per million) indicating the amount of NOx at each location where the NOx sensor is located. Temperature sensors are configured to acquire data indicating the temperature at their location. PM sensors are configured to monitor particulate matter flowing through the aftertreatment system 120.

[0055] Sensor 125 can be positioned after engine 101 and before after-treatment system 120, and between after-treatment system components as shown (e.g., coupled to DPF and / or DOC, coupled to SCR, etc.). It should be understood that the sensor's position can vary. In one embodiment, sensor 125 can be placed both before and after after-treatment system 120. In one embodiment, at least one of the sensors is configured as an exhaust component sensor (e.g., a sensor for CO, NOx, PM, SOx, etc.). In another embodiment, at least one of the sensors 125 is configured as a non-exhaust component sensor for estimating exhaust emissions (e.g., temperature, flow rate, etc.). Additional sensors may also be included with system 100. Sensors may include engine-related sensors (e.g., torque sensors, speed sensors, pressure sensors, flow rate sensors, temperature sensors, etc.). Sensors may also include sensors associated with other components of the vehicle (e.g., turbocharger speed sensors, fuel quantity and injection rate sensors, fuel rail pressure sensors, etc.).

[0056] Sensors can be real or virtual (i.e., non-physical sensors configured to make various estimates or determinations within the controller's program logic). For example, an engine speed sensor can be a real or virtual sensor arranged to measure or otherwise acquire data, values, or information indicating the speed of engine 101 (typically expressed in revolutions per minute). When configured as a real sensor, the sensor is coupled to the engine and configured to send a signal indicating the speed of engine 101 to controller 140. When configured as a virtual sensor, controller 140 can use at least one input in an algorithm, model, lookup table, etc., to determine or estimate engine parameters (e.g., power output, etc.). Other sensors can also be real or virtual.

[0057] The controller 140 is communicatively coupled to the sensor 125. Therefore, the controller 140 is configured to receive data from one or more of the sensors 125. The received data can be used by the controller 140 for one or more components of the control system 100 and / or for monitoring and diagnostic purposes.

[0058] Still refer to Figure 1 Operator input / output (I / O) device 130 is also shown. Operator I / O device 130 can be communicatively coupled to controller 140, allowing information to be exchanged between controller 140 and I / O device 130, wherein the information may involve... Figure 1 The determination of one or more components or controllers 140 (described below). Operator I / O device 130 enables the operator of system 100 to communicate with controller 140 and... Figure 1The system 100 communicates with one or more components. For example, operator input / output device 130 may include, but is not limited to, an interactive display, a touchscreen device, one or more buttons and switches, a voice command receiver, etc. In various alternative embodiments, the controller 140 and components described herein may be implemented with non-vehicle applications (e.g., generators). Therefore, the I / O device may be application-specific. For example, in these cases, the I / O device may include a laptop computer, tablet computer, desktop computer, telephone, watch, personal digital assistant, etc. Via the operator I / O device, the controller 140 may provide diagnostic information, fault, or service notifications based on one or more measurements. For example, in some embodiments, the controller 140 may display the temperature of DOC 121, the temperature of engine 101 and exhaust gas, and various other information via the operator I / O device.

[0059] Controller 140 is configured to at least partially control the operation of system 100 and associated subsystems such as post-processing system 120 (and various components of each system) and operator input / output (I / O) devices 130. Communication between and within components can be via any number of wired or wireless connections. For example, wired connections may include serial cables, fiber optic cables, CAT5 cables, or any other form of wired connection. In contrast, wireless connections may include the Internet, Wi-Fi, cellular, radio, etc. In one embodiment, a controller local area network (CAN) bus provides the exchange of signals, information, and / or data. The CAN bus includes any number of wired and wireless connections. Because controller 140 can communicatively connect to... Figure 1 The system and components, so the controller 140 is configured to receive from Figure 1 Data for one or more components shown. Regarding... Figure 2 The structure and function of controller 140 are further described.

[0060] The telematics unit 150 may include, but is not limited to, one or more memory devices for storing tracking data, one or more electronic processing units for processing tracking data, and a communication interface for facilitating data exchange between the telematics unit 150 and one or more remote devices (e.g., providers / manufacturers of telematics devices, etc.). In this regard, the communication interface can be configured as any type of mobile communication interface or protocol, including but not limited to Wi-Fi, WiMax, the Internet, radio, Bluetooth, Zigbee, satellite, radio, cellular, GSM, GPRS, LTE, etc. The telematics unit 150 may also include a communication interface for communicating with the controller 140 of the system 100. The communication interface for communicating with the controller 140 may include any type and number of wired and wireless protocols (e.g., any standard conforming to IEEE 802, etc.). For example, wired connections may include serial cables, fiber optic cables, SAE J1939 buses, CAT5 cables, or any other form of wired connection. In contrast, wireless connections may include the Internet, Wi-Fi, Bluetooth, Zigbee, cellular, radio, etc. In one embodiment, a controller local area network (CAN) bus comprising any number of wired and wireless connections provides the exchange of signals, information, and / or data between controller 140 and telematics unit 150. In other embodiments, a local area network (LAN), wide area network (WAN), or external computer (e.g., via the Internet through an Internet service provider) can provide, facilitate, and support communication between telematics unit 150 and controller 140. In yet another embodiment, communication between telematics unit 150 and controller 140 is implemented via the Unified Diagnostic Services (UDS) protocol. All such variations are intended to fall within the spirit and scope of this disclosure.

[0061] Now refer to Figure 2 This illustrates an exemplary embodiment. Figure 1 A schematic diagram 200 of the controller 140 is provided. The controller 140 may be configured as one or more electronic control units (ECUs). The controller 140 may be separate from or included in at least one of a transmission control unit, an exhaust aftertreatment control unit, a powertrain control module, an engine control module, etc. In one embodiment, the components of the controller 140 are combined into a single unit. In another embodiment, one or more components may be geographically distributed throughout the system. All such variations are intended to fall within the scope of this disclosure. The controller 140 is shown as including a processing circuit 202 having a processor 204 and a memory device 206, a thermal management circuit 210, an aging circuit 212, and a communication interface 216.

[0062] In one configuration, thermal management circuitry 210 and aging circuitry 212 are embodied as a machine- or computer-readable medium storing instructions executable by a processor (e.g., processor 204). As described herein and in other uses, a machine-readable medium facilitates the performance of certain operations to achieve the reception and transmission of data. For example, a machine-readable medium can provide instructions (e.g., commands, etc.) to, for example, acquire data. In this regard, a machine-readable medium may include programmable logic defining the frequency of data acquisition (or data transmission) and other functions. A computer-readable medium may include code that can be written in any programming language, including but not limited to Java and any conventional procedural programming language, such as the "C" programming language or similar programming languages. The computer-readable program code can be executed on one processor or multiple remote processors. In the latter case, the remote processors can be interconnected via any type of network (e.g., CAN bus, etc.).

[0063] In another configuration, thermal management circuitry 210 and aging circuitry 212 are embodied as hardware units. Therefore, thermal management circuitry 210 and aging circuitry 212 may include one or more circuit components, including but not limited to processing circuitry, network interfaces, peripheral devices, input devices, output devices, sensors, etc. In some embodiments, thermal management circuitry 210 and aging circuitry 212 may take the form of one or more analog circuits, electronic circuits (e.g., integrated circuits (ICs), discrete circuits, system-on-a-chip (SOC) circuits, microcontrollers, etc.), telecommunications circuits, hybrid circuits, and any other type of "circuit". In this respect, thermal management circuitry 210 and aging circuitry 212 may include any type of components for performing or facilitating the implementation of the operations described herein. For example, the circuitry described herein may include one or more transistors, logic gates (e.g., NAND, AND, NOR, OR, XOR, NOT, XNOR, etc.), resistors, multiplexers, registers, capacitors, inductors, diodes, wiring, etc. Thermal management circuitry 210 and aging circuitry 212 may also include programmable hardware devices, such as field-programmable gate arrays, programmable array logic, programmable logic devices, etc. The thermal management circuit 210 and aging circuit 212 may include one or more memory devices for storing instructions executable by the processor of the thermal management circuit 210 and aging circuit 212. The one or more memory devices and the processor may have the same definitions provided below regarding memory device 206 and processor 204. In some hardware unit configurations and as described above, the thermal management circuit 210 and aging circuit 212 may be geographically distributed across various locations within the system. Alternatively, and as shown, the thermal management circuit 210 and aging circuit 212 may be embodied in or within a single unit / housing, shown as controller 140.

[0064] In the illustrated example, controller 140 includes processing circuitry 202 having processor 204 and memory device 206. Processing circuitry 202 may be constructed or configured to execute or implement the instructions, commands, and / or control processes described herein with respect to thermal management circuitry 210 and aging circuitry 212. The depicted configuration represents thermal management circuitry 210 and aging circuitry 212 as a machine- or computer-readable medium. However, as noted above, this illustration is not intended to be limiting, as this disclosure contemplates other embodiments of thermal management circuitry 210 and aging circuitry 212, or at least one of a plurality of circuits of thermal management circuitry 210 and aging circuitry 212, configured as hardware units. All such combinations and variations are intended to fall within the scope of this disclosure.

[0065] Processor 204 may be implemented as one or more processors, application-specific integrated circuits (ASICs), one or more field-programmable gate arrays (FPGAs), digital signal processors (DSPs), a set of processing units, or other suitable electronic processing units. In some embodiments, one or more processors may be shared by multiple circuits (e.g., thermal management circuitry 210 and aging circuitry 212 may include or otherwise share the same processor, which in some exemplary embodiments may execute instructions stored or otherwise accessed via different regions of memory). Alternatively or additionally, one or more processors may be configured to perform or otherwise perform certain operations independently of one or more coprocessors. In other exemplary embodiments, two or more processors may be interconnected via a bus to enable independent, parallel, pipelined, or multithreaded instruction execution. All such variations are intended to fall within the scope of this disclosure.

[0066] Memory device 206 (e.g., memory, memory cell, storage device) may include one or more means or components (e.g., RAM, ROM, flash memory, hard disk storage) for storing data and / or computer code to perform or facilitate the various processes, layers, and modules described herein. Memory device 206 may be communicatively connected to processor 204 to provide processor 204 with computer code or instructions for performing at least some of the processes described herein. Furthermore, memory device 206 may be or include tangible, non-transient volatile memory or non-volatile memory. Therefore, memory device 206 may include database components, object code components, scripting components, or any other type of information structure for supporting the various activities and information described herein.

[0067] Communication interface 216 may include any combination of wired and / or wireless interfaces (e.g., jacks, antennas, transmitters, receivers, transceivers, wired terminals) for data communication with various systems, devices, or networks configured to enable in-vehicle communication (e.g., between and within components of the vehicle) and, in some embodiments, out-of-vehicle communication (e.g., communication with a remote server via a telematics unit). For example, regarding out-of-vehicle / system communication, communication interface 216 may include Ethernet cards and ports for sending and receiving data via an Ethernet-based communication network and / or Wi-Fi transceivers for communication via a wireless communication network. Communication interface 216 may be configured to communicate via a local area network or a wide area network (e.g., the Internet) and may use various communication protocols (e.g., IP, LON, Bluetooth, ZigBee, radio, cellular, near-field communication).

[0068] Communication interface 216 can facilitate communication between controller 140 and one or more components of system 100 (e.g., engine 101, aftertreatment system 120, sensor 125, etc.). Communication between or among the components of controller 140 and system 100 can be via any number of wired or wireless connections (e.g., any IEEE standard). For example, wired connections can include serial cables, fiber optic cables, CAT5 cables, or any other form of wired connection. In one embodiment, a controller local area network (CAN) bus provides the exchange of signals, information, and / or data. The CAN bus can include any number of wired and wireless connections providing the exchange of signals, information, and / or data. The CAN bus can include a local area network (LAN) or a wide area network (WAN), or can be connected to an external computer (e.g., via the Internet through an Internet service provider).

[0069] Thermal management circuit 210 is configured to activate and deactivate thermal management modes of control system 100. Specifically, thermal management circuit 210 controls the activation and deactivation of thermal management modes based on dynamically controlling and adjusting entry and exit temperature thresholds. Specifically, and as described herein, thermal management circuit 210 adjusts the entry and exit temperature thresholds of the aftertreatment system based on airspeed and the aging of the aftertreatment system or its components. Thermal management circuit 210 can activate thermal management modes to increase aftertreatment temperatures to, for example, reduce NOx emissions (e.g., by lowering the entry temperature threshold of the thermal management mode to result in more frequent implementation of the thermal management mode). As described above, there are entry and exit temperature thresholds for thermal management modes. When the temperature is at or below the entry temperature threshold, thermal management circuit 210 activates the thermal management mode. When the temperature reaches or exceeds the exit temperature threshold, the thermal management mode is deactivated to facilitate normal operation of the vehicle / system. As described herein, the entry and exit temperature thresholds are dynamically adjusted based on the aging of the aftertreatment system. This determination can be based on the aging of the aftertreatment system and airspeed, as referenced herein. Figures 3-5 As explained. This determination can also be based on the system output NOx amount or NOx conversion value in order to continuously reduce NOx output (e.g., by comparing the system output NOx amount with the desired level and adjusting the entry and exit temperature thresholds as a response).

[0070] By adjusting the entry and exit temperature thresholds for the thermal management mode, the thermal management circuit 210 controls how frequently or infrequently the thermal management mode is triggered on / off. Advantageously, as the aftertreatment system ages or experiences a failure condition, lowering the entry temperature threshold results in the thermal management mode being triggered more frequently. Therefore, even if the aftertreatment system ages or experiences a failure condition, the controller 140 actively helps promote catalytic activity via the thermal management mode, thereby reducing or mitigating emissions (e.g., NOx). Static thermal management mode entry and exit temperature thresholds may lead to unnecessary activation / deactivation of the thermal management mode. Furthermore, with static thresholds, the thermal management mode may be unnecessarily controlled, which may result in increased wear and tear on the aftertreatment system. By dynamically adjusting the entry and exit thresholds, emissions are better controlled, while thermal management is performed at a more precisely defined time. It should be understood that multiple thermal management modes may exist, each corresponding to a different action (e.g., mode one includes post-injection, while mode two includes post-injection and activation of the electric heater). This disclosure applies to a variety of different thermal management modes.

[0071] The “temperature” for the entry and exit temperature thresholds can be exhaust temperature, component temperature (e.g., SCR temperature), and / or a combination thereof. In the illustrated example, temperature refers to a determined or estimated SCR temperature (typically an aftertreatment system temperature). Temperature can be determined based on data from one or more of the aforementioned sensors 125 (or directly by one or more sensors). Aftertreatment temperature can be determined at various locations (e.g., system output temperature downstream of the aftertreatment system, between the engine and the aftertreatment system, such as engine output temperature, within the aftertreatment system, or some combination thereof). Aftertreatment temperature can be determined based on temperature data acquired by sensor 125 such that the aftertreatment temperature is determined at or near the sensor location (e.g., at various locations within engine 101 and / or aftertreatment system 120). For example, sensor 125 can be a DOC temperature sensor configured to determine or estimate the temperature at the DOC inlet or outlet of the aftertreatment system 120. Sensor 125 can be an SCR temperature sensor configured to determine or estimate the temperature at the SCR inlet or outlet of the aftertreatment system 120. The aftertreatment temperature can be determined based on temperature data from more than one sensor 125 located at various locations within the engine 101 and / or aftertreatment system 120 at various operating times. For example, a system output temperature sensor can be located at or near the outlet point of the engine exhaust aftertreatment system (e.g., in the tailpipe) to determine the outlet temperature at a specific time. In another embodiment, the aftertreatment temperature at that location can be determined based on the average temperature over a predetermined duration. Furthermore, the controller 140 can determine how long the aftertreatment temperature has remained above a predefined threshold and whether that duration has exceeded the predefined threshold time period. Figure 1 As shown, two or more sensors may be present, positioned throughout the aftertreatment system 120 (near the SCR, DPF, DOC, etc.), to determine the aftertreatment temperature. The thermal management circuit 210 may determine the aftertreatment temperature based on an average temperature (e.g., average, median, etc.) determined over a predefined duration, the distance traveled by the vehicle (e.g., 100,000 miles), at a specific operating time of the vehicle, or how long the aftertreatment temperature has been maintained beyond a predefined time period.

[0072] Thermal management circuit 210 is configured to selectively activate and deactivate thermal management modes of system 100. In one embodiment, activation and deactivation are automatic based on aftertreatment system temperature, and particularly on SCR temperature. As part of the thermal management modes, thermal management circuit 210 is configured to provide one or more commands to increase the temperature of the aftertreatment system to promote catalytic activity. Thermal management circuit 210 may utilize commands to increase the power output (e.g., torque and / or speed) of engine 101. Higher speed and torque promote higher exhaust temperatures, which can increase SCR catalyst temperature. Thermal management circuit 210 may utilize additional thermal management mode commands, such as controlling (e.g., shutting down or otherwise actuating) air treatment actuators, such as turbocharger position, EGR position (e.g., EGR valve), etc. Thermal management circuit 210 may also be coupled to the fuel supply system to control, for example, fuel rail pressure and other fuel supply commands of the engine (e.g., increasing and / or decreasing the quantity and amount of injected fuel). Higher load and power demands tend to increase combustion temperatures. Higher power output corresponds to higher fuel pressure and quantity (increased fuel rail pressure). Furthermore, increasing fuel supply pressure and quantity often contributes to higher exhaust temperatures. Additional commands may include, but are not limited to, post-injection commands (injecting fuel after combustion, which is used to induce higher exhaust temperatures), cylinder deactivation commands (e.g., shutting down some cylinders of the engine, causing the cylinders in use to work harder to maintain the desired power output that leads to higher exhaust temperatures), activating electric heaters located in the aftertreatment system, changing injection timing (e.g., delaying injection), changing the position of the intake throttle valve (e.g., closing the intake throttle valve), and controlling (e.g., closing or otherwise actuating) other air treatment actuators, such as intake bypass valves (e.g., selectively closing / opening / partially opening the intake bypass valve to bypass intake air), exhaust bypass valves (e.g., selectively opening / closing / partially opening the exhaust bypass valve to bypass the exhaust duct), exhaust gas recirculation (EGR) valves (e.g., selectively opening / closing / partially opening the EGR valve to provide EGR to the engine bypass), etc. The commands used may be based on various factors, such as whether the vehicle is stationary or moving, a given NOx conversion efficiency, etc. Therefore, not all commands can be used every time. The thermal management circuit 210 can selectively utilize one or more of the aforementioned commands (or other commands) in the active thermal management mode.

[0073] Aging circuit 212 is configured to determine or estimate the aging of the aftertreatment system or its components. As described herein, aging condition refers to the condition of the aftertreatment system or its components based on the use of system 100. As the system ages, its operational efficiency may decrease due to factors such as buildup, reduced catalytic activity, etc. Aging circuit 212 is configured to communicate with thermal management circuit 210, so that thermal management circuit 210 can operate based on the determinations made by aging circuit 212.

[0074] Now refer to Figure 3 The logic of an aging circuit 212 according to an exemplary embodiment is shown. Specifically, an exemplary flowchart for determining the aging condition of a system is depicted. Method 300 includes a process 302 for determining the equivalent time at a reference temperature for the SCR. In this regard, at process 302, time and SCR temperature are received by the aging circuit 212. The aging circuit 212 can utilize a model or lookup table to determine the time equivalent at the reference temperature. For example, temperatures at different times can be recorded over a period of time. These data points can be grouped into equivalent times at various temperatures; in this way, temperature fluctuations do not result in a large number of data points (e.g., 101°C at 5 minutes, 103°C at 15 minutes, and 109°C at 35 minutes can be determined by the aging circuit 212 as 110°C for 30 minutes). Therefore, the aging circuit 212 can determine and utilize various groups.

[0075] At process 304, the fuel sulfur concentration is determined by aging circuit 212 using the fuel ratio and sulfur content. In this regard, aging circuit 212 can use the following formula: (fuel ratio) x (sulfur content). This formula estimates the amount of fuel sulfur concentration. At process 306, aging circuit 212 calculates the sulfur content in the aftertreatment system (specifically the SCR) based on the determined amount of fuel sulfur concentration, SCR temperature, the temperature threshold for desulfurization, and time. Since sulfur-induced degradation is largely reversible, aftertreatment system regeneration events can be used to reverse sulfur-induced degradation. When the SCR is exposed to sulfur, typically from the fuel, sulfur begins to deactivate some active sites on the SCR catalyst. Sulfur reduces the overall SCR conversion efficiency. The temperature threshold for desulfurization indicates the aftertreatment system temperature at which a sulfur regeneration event occurs. The time above this temperature threshold is used to determine the sulfur content; specifically, this value is tracked after a minimum time has been reached. Increasing the time the determined fuel sulfur concentration remains above the desulfurization temperature can increase wear on the aftertreatment system (e.g., the SCR catalyst).

[0076] At process 308, the aging circuit 212 estimates or determines the aging condition of the SCR. The time equivalent at a reference temperature (process 302), sulfur content determination (process 306), and ammonia-NOx ratio (ANR) are used as inputs to estimate the SCR aging condition. In the example shown, the SCR aging condition is estimated when the ANR is above 1 (indicating a relatively high ammonia content). These inputs can be fed into a table, such as a lookup table, in which the aging circuit 212 then determines the aging condition or status of the SCR (e.g., healthy, deteriorated, operable but requiring servicing, etc.).

[0077] At process 310, the aging condition of the DOC is estimated by aging circuit 212. Aging circuit 212 uses the time equivalent at a reference temperature (process 302) and the sulfur content measurement on the catalyst (process 306) as inputs. Similar to process 308, aging circuit 212 can use a table such as a lookup table to determine the aging condition or status of the DOC (e.g., healthy, deteriorated, operable but may require servicing, etc.).

[0078] At process 312, aging circuit 212 determines or estimates the aging condition of the post-processing system based on the estimated SCR and DOC aging conditions (processes 308 and 310). In other embodiments, the determined SCR or DOC aging condition can be used alone to represent the aging condition of the post-processing system. In this respect, and as shown, Figure 3 The upper part is an aging estimate based on temperature, as high temperatures affect SCR and DOC aging. The lower part is the effect of sulfur on SCR and DOC aging. These two parts are calculated and combined to determine the aging estimate for the post-treatment system 120. Higher temperatures can improve conversion efficiency but also increase aging. Similarly, the higher the sulfur content over time, the greater the adverse effect on aging. Advantageously, method 300 takes these factors into account when determining aging conditions.

[0079] Based on the foregoing, Figure 4 and Figure 5 An example process / logic for a controller 140 used to dynamically adjust thermal management entry and exit temperature thresholds is described. Figure 4 The first embodiment is shown in the figure. Figure 5 The second embodiment is shown. In each embodiment, the aging circuit 212 estimates the aging condition of the post-processing system (e.g., based on...). Figure 3 Furthermore, the thermal management circuit 210, in conjunction with other processes, utilizes this determination to adjust the thermal management mode entry and exit temperature thresholds. Figure 4 The incremental adjustment of thermal management entry and exit temperature thresholds is shown, while Figure 5 The diagram shows the temperature thresholds for entering and exiting the thermal management mode, which are adjusted according to predefined values.

[0080] First refer to Figure 4At process 402, the controller uses the exhaust flow rate and the dimensions of the aftertreatment system 120 to determine the space velocity through the aftertreatment system 120. In operation, the aftertreatment system model can be recorded and known dimensions referenced to determine the dimensions (e.g., volume) of the aftertreatment system or its components (SCR reactor chamber). For example, the aftertreatment system identifier can be sent to a remote system via telematics unit 150 to identify / determine the dimensions of the aftertreatment system or its components. Alternatively, known dimensions can be programmed into memory device 206. Thermal management circuitry 210 determines the space velocity by measuring or estimating the exhaust flow rate (particularly through the SCR) and dividing that flow rate by the space volume (particularly the SCR). In operation, for a given temperature condition, as the space velocity decreases, more time is spent in the catalyst for conversion, thus generally increasing the conversion efficiency (e.g., NOx conversion). Conversely, if the space velocity increases, the conversion efficiency (particularly NOx conversion) decreases (i.e., the exhaust moves through the catalyst faster, meaning the SCR catalyst has less time to act on that exhaust to reduce NOx emissions). Therefore, space velocity becomes an important input for understanding SCR conversion efficiency.

[0081] At process 404, aging circuit 212 is determined as follows: Figure 3 The aging condition of the post-processing system. As described herein, aging condition can be a value indicating the amount of degradation of the post-processing system (particularly specific components, such as SCR and / or DOC). This value can be expressed as a numerical value (e.g., one to one hundred), alphanumeric characters (e.g., A for minimum degradation and D for basic degradation), code, etc. Figure 3The inputs shown are combined, and various parameters can be used to determine the estimated aging condition of the aftertreatment system. Aftertreatment aging has a significant impact on SCR conversion efficiency, and multiple factors can lead to system aging. For example, aging may be caused by prolonged exposure to high temperatures or exposure to sulfur in the fuel. Parameters used in the aftertreatment aging estimator may include time (i.e., system on-time), mileage, duty cycle value, fuel rate, aftertreatment temperature for DOC, DPF, and / or SCR, the amount of time the aftertreatment temperature is maintained above a predefined temperature threshold, and / or the number of active regeneration events. In some embodiments, the duty cycle includes at least one of mileage, fuel consumption per unit time and / or distance, average speed over time, and / or average load over time. At least one or more of these factors may be used. Aging circuit 212 may utilize one or more lookup tables containing these factors to determine the aging condition value of the system. For example, if high oil consumption in the engine is due to a defect in the lubrication system, more oil may flow through the aftertreatment system, which may adversely affect the operation of the aftertreatment system. During the initial installation of the aftertreatment system, oil consumption is very low, but with wear and tear, higher oil consumption occurs, becoming another source of sulfur in the exhaust stream. Furthermore, if the SCR is upstream of the DOC, phosphorus and other oil-based contaminants can affect aging. Since the DOC precedes the SCR, the aging of both the SCR and DOC can be determined. For example, the feed gas enters the SCR from the DOC, and therefore the health condition of the exhaust feed gas in the SCR is determined by the health condition of the DOC. Therefore, the SCR and DOC are interrelated; as the DOC ages, the feed gas quality changes, which is important because if the feed gas estimate is known, then the acidity can be known. However, either the SCR or the DOC can be used in the estimate.

[0082] The aging circuit 212 can also track the number of active regeneration events to estimate the aging condition of the aftertreatment system. Regeneration refers to burning off deposits in the aftertreatment system to restore or improve system operation. Regeneration can occur actively or passively. Active regeneration originates from a specific command designed to regenerate the aftertreatment system or its components (e.g., commanding high power output plus activation of the electric heater). Passive regeneration refers to regeneration events that occur naturally during system operation (e.g., under high load conditions, the aftertreatment system temperature can rise to induce regeneration), where the exhaust temperature and / or the temperature of the aftertreatment system components reach a predefined range or threshold (or, alternatively, certain conditions occur, such as an increase in flow rate through the DPF, indicating that deposits are being burned off from the filter). The controller 140 can track the number and duration of commanded active regeneration events. The aging circuit 212 can also count the number and duration of passive regeneration events. Based on the increased number and duration of active and / or passive regeneration events, the aging circuit 212 can determine the increased “aging condition” of the aftertreatment system. In other words, as an example, this condition promotes the aging of the SCR when it is exposed to high temperatures during a regeneration event.

[0083] At process 406, controller 140 (specifically thermal management circuit 210) adjusts the entry temperature threshold and / or exit temperature threshold of the thermal management mode based on a determined airspeed (process 402) and a determined aging condition (process 404). Based on these data points (two data points—a determined airspeed and a determined aging condition), thermal management circuit 210 determines at least one of the entry temperature threshold or exit temperature threshold for at least one thermal management mode. The thermal management mode may have preset thermal management entry temperature thresholds and exit temperature thresholds (stored in memory device 206). At process 406, incremental adjustment of these stored entry temperature thresholds and exit temperature thresholds is performed by controller 140 (specifically thermal management circuit 210). Specifically, the thermal management mode entry temperature threshold and / or exit temperature threshold are adjusted incrementally upward or downward based on a feedback loop (process 408).

[0084] Therefore, referring more specifically to process 408, the thermal management circuit 210 is configured to determine the error in the SCR conversion efficiency based on the desired system output NOx and the determined system output NOx (i.e., the actual system output NOx). A system output NOx sensor can acquire data indicating the system output NOx. This value is then compared to the desired system output NOx, which can be based on emission regulations or another predefined value (e.g., determined by the manufacturer, operator, etc.). The difference between the desired system output NOx and the system output NOx is the "error". If the error is less than a predefined threshold, no further adjustment is made to at least one of the inlet temperature threshold or the outlet temperature threshold. However, if the error is greater than the predefined threshold, the thermal management circuit 210 adjusts at least one of the inlet temperature threshold or the outlet temperature threshold incrementally (e.g., up or down less than 10 degrees Celsius). The predefined threshold can be a predefined value from the manufacturer (or operator). The predefined threshold can be a static value or a dynamic value that changes over time (e.g., updated as vehicles age, etc.).

[0085] The incremental adjustment can be predefined or a function of comparing a determined error value with a predefined threshold. Regarding the predefined amount, the incremental adjustment can be a predefined upward or downward adjustment (e.g., 10 degrees Celsius), or a predefined amount specific to the entry and exit temperature thresholds (e.g., a change of 10 degrees Celsius for the entry temperature threshold and a change of 15 degrees Celsius for the exit temperature threshold). Regarding the function of the comparison, a larger error relative to the threshold can correspond to a larger incremental adjustment (e.g., if the error is X greater than the threshold, the adjustment is X; and if the error is X+Y greater than the threshold, the adjustment is X+Y).

[0086] The controller 140 can continuously execute process 408 until the error is less than or equal to the threshold. At this point, emissions have been controlled so that the determined SCR conversion efficiency meets the target or desired SCR conversion efficiency.

[0087] Conversion efficiency, quantity, or value can also be determined relative to the entire aftertreatment system and / or the entire system. Treating the system as a whole, the system output NOx conversion efficiency can be determined as: (Engine output NOx - System output NOx) / (Engine output NOx). A similar method can be used for the aftertreatment system: (Aftertreatment system NOx feed rate - Aftertreatment system NOx emissions) / (Aftertreatment system NOx feed rate). Therefore, conversion efficiency can be determined across various components. Furthermore, the inlet and outlet temperature thresholds can be adjusted based on NOx values ​​(e.g., system output NOx conversion value).

[0088] Now refer to Figure 5This illustrates a process 500 for adjusting the entry and exit temperature thresholds of a thermal management mode according to an exemplary embodiment. Processes 502 and 504 correspond to processes 402 and 404 of process 400. However, process 506 depicts adjusting the entry and exit temperature thresholds of the thermal management mode according to predefined values. Specifically, adjustment is performed according to a lookup table that can be stored in memory 206 or stored in the thermal management circuit 210. In operation, airspeed and determined aging (processes 502 and 504) represent two data points, which are then used in a lookup table accessed by the thermal management circuit 210 to determine an adjustment value for at least one of the thermal management entry or exit temperature thresholds. The adjustment of the thermal management entry and exit temperature thresholds can be an adjustment value (e.g., adding 5 degrees Celsius to the entry temperature threshold) or a specific setpoint for the entry and / or exit temperature thresholds (e.g., 150 degrees Celsius for the entry temperature threshold). Figure 4 Instead of executing an active control loop that adjusts the temperature threshold and compares it to the SCR conversion efficiency, the controller at process 506 utilizes a pre-defined lookup table. The lookup table can be developed based on experimental testing. Therefore, SCR conversion efficiency or error is not used when adjusting the inlet and outlet temperature thresholds. Figure 4 In comparison, this process may be advantageous in terms of saving processing power.

[0089] Similar to Figure 4 The thermal management circuit 210 is configured to communicate with and at least partially control the post-processing system 120. For example, based on determinations made by the aging circuit 212, commands are sent to adjust the post-processing system temperature thresholds. When SCR conversion efficiency decreases, the entry and exit temperature thresholds can be adjusted due to more aging or higher space velocity.

[0090] Based on the foregoing, the following provides information on what can be used... Figure 4 or Figure 5 Examples of adjustments performed. The determined airspeed and aging conditions (processes 402, 502 and processes 404, 504) can indicate that the aftertreatment system (e.g., SCR) has deteriorated (e.g., reached a predefined level or some other metric) by a greater than expected amount. For example, in Figure 4 and Figure 5In this configuration, two data points indicate a change in at least one of the entry temperature threshold or the exit temperature threshold for thermal management mode. Alternatively, the data points may indicate that no change is needed (the current entry and / or exit thresholds are consistent with the determined adjustment setpoints, therefore no change is implemented). In this respect, if the entry temperature threshold is set too low, the SCR may be exposed to contaminants, and thermal management circuit 210 is configured to increase the entry temperature threshold. Conversely, if the entry temperature threshold is set too high, the system may age undesirably rapidly, and emissions may be affected. Therefore, thermal management circuit 210 is configured to decrease the entry temperature threshold for thermal management mode.

[0091] In a specific example, based on the determination that the aftertreatment system has deteriorated and requires adjustment, controller 140 can adjust the inlet temperature threshold for thermal management to a lower level (i.e., lower the inlet thermal management temperature threshold), resulting in the triggering of a thermal management mode at a lower temperature. This, in turn, triggers the thermal management mode more frequently to help raise the treatment system temperature, thereby aiding the operation of the aftertreatment system (e.g., NOx conversion). Additionally, the exit temperature threshold can be raised / increased to prolong the thermal management mode. Therefore, compared to existing thermal management modes, the thermal management mode can be controlled at a lower temperature and last for a relatively longer period. Advantageously, this can alleviate stress on the aftertreatment system to effectively reduce harmful emissions (e.g., NOx).

[0092] As another specific example, controller 140 can determine, based on determined aging conditions and airspeed, that the aftertreatment system is performing as desired or better (processes 402, 502 and processes 404, 504). Furthermore, controller 140 can raise the thermal management mode entry temperature threshold, causing controller 140 to issue commands for thermal management modes less frequently. Some thermal management commands may cause stress or other potentially undesirable conditions on one or more components of the aftertreatment system (e.g., post-injection may lead to decreased fuel economy due to the fuel used in post-injection). Therefore, by reducing the frequency of commanded thermal management modes, the occurrence of potential undesirable conditions can be reduced.

[0093] By dynamically adjusting the inlet and outlet temperature thresholds based on aging conditions, additional losses and damage caused by elevated temperatures can be reduced. In this respect, adjusting the inlet and outlet thresholds can provide a robust system that proactively addresses emissions (e.g., NOx emissions) from aging components (e.g., SCRs). Therefore, this disclosure can advantageously extend the health of, for example, SCR catalysts and ensure compliance with emission regulations as SCR catalysts age over time.

[0094] As used herein, the terms “about,” “approximately,” “substantially,” and similar terms are intended to have a broad meaning consistent with common and acceptable usage by one of ordinary skill in the art to which the subject matter of this disclosure pertains. Those skilled in the art who consult this disclosure will understand that these terms are intended to allow for the description of certain features described and claimed, without limiting the scope of these features to the precise numerical ranges provided. Therefore, these terms should be interpreted as indicating that non-substantial or irrelevant modifications or alterations to the described and claimed subject matter are considered to be within the scope of the disclosure set forth in the appended claims.

[0095] It should be noted that the term "exemplary" and its variations, as used herein to describe various embodiments, are intended to indicate that these embodiments are possible examples, representations, and / or illustrations of possible embodiments (and the term is not intended to imply that such embodiments are necessarily extraordinary or the best examples).

[0096] As used herein, the term "connection" and its variations refer to the direct or indirect linking of two components to each other. This connection can be fixed (e.g., permanent or immutable) or movable (e.g., removable or releasable). Such a connection can be achieved by directly linking two components to each other, by linking two components to each other using one or more separate intermediate components, or by linking two components to each other using an intermediate component that forms a single whole with one of the two components. If "connection" or its variations are modified by an appended term (e.g., direct connection), the general definition of "connection" provided above is modified by the simple linguistic meaning of the appended term (e.g., "direct connection" means a connection of two components without any separate intermediate components), resulting in a narrower definition than the general definition of "connection" provided above. Such a connection can be mechanical, electrical, or fluid. For example, circuit A being "connected" to circuit B can mean that circuit A communicates directly with circuit B (i.e., without an intermediary) or indirectly with circuit B (e.g., through one or more intermediaries).

[0097] Despite Figure 2 Various circuits with specific functions are illustrated herein; however, it should be understood that controller 140 may include any number of circuits for performing the functions described herein. For example, the activities and functions of thermal management circuit 210 and aging circuit 212 may be combined into multiple circuits or a single circuit. Additional circuits with additional functions may also be included. Furthermore, controller 140 may further control other activities beyond the scope of this disclosure.

[0098] As described above, and in one configuration, the "circuit" can be implemented in a machine-readable medium for execution by various types of processors, such as... Figure 2The processor 204. The identified circuitry of the executable code may, for example, comprise one or more physical or logical blocks of computer instructions, which may be organized, for example, into objects, processes, or functions. However, the executable of the identified circuitry does not need to be physically located together, but may include different instructions stored in different locations that, when logically connected, comprise the circuitry and implement the circuitry's stated purpose. In practice, the circuitry of computer-readable program code may be a single instruction or multiple instructions, and may even be distributed across several different code segments, between different programs, and across several memory devices. Similarly, operational data may be identified and represented herein within the circuitry, and may be embodied in any suitable form and organized within any suitable type of data structure. Operational data may be collected as a single dataset, or may be distributed across different locations, including different storage devices, and may exist at least in part simply as electronic signals within a system or network.

[0099] Although the term "processor" has been briefly defined above, the terms "processor" and "processing circuit" are intended to be interpreted broadly. In this respect, and as stated above, a "processor" can be implemented as one or more general-purpose processors, application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), digital signal processors (DSPs), or other suitable electronic data processing components configured to execute instructions provided by memory. One or more processors can take the form of a single-core processor, a multi-core processor (e.g., a dual-core processor, a triple-core processor, a quad-core processor, etc.), a microprocessor, etc. In some embodiments, one or more processors can be external to an organization; for example, one or more processors can be remote processors (e.g., cloud-based processors). Alternatively or additionally, one or more processors can be internal to a device and / or local. In this regard, a given circuit or its components can be located locally (e.g., as part of a local server, a local computing system, etc.) or remotely (e.g., as part of a remote server such as a cloud-based server). Therefore, the term "circuit" as used herein can include components distributed in one or more locations.

[0100] Although the accompanying drawings and descriptions may show a specific order of method steps, this order may differ from the order depicted and described unless otherwise specified above. Furthermore, two or more steps may be performed simultaneously or partially simultaneously unless otherwise specified above. For example, such variations may depend on the chosen software and hardware system and the designer's choices. All such variations are within the scope of this disclosure.

[0101] For purposes of illustration and description, the foregoing description of embodiments has been presented. It is not intended to be exhaustive or to limit the present disclosure to the precise forms disclosed, and modifications and variations are possible or available from the present disclosure in accordance with the foregoing teachings. The embodiments were chosen and described to explain the principles of the present disclosure and its practical application, enabling those skilled in the art to utilize the various embodiments and make various modifications suitable for the particular purpose intended. Other substitutions, modifications, alterations, and omissions may be made in the design, operating conditions, and arrangement of the embodiments without departing from the scope of the present disclosure as set forth in the appended claims.

[0102] Therefore, this disclosure may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered illustrative in all respects only, and not restrictive. Therefore, the scope of this disclosure is indicated by the appended claims rather than by the foregoing description. All variations within the equivalent meaning and scope of the claims should be included within their scope.

Claims

1. A system for controlling thermal management modes, comprising: An exhaust aftertreatment system, which is connected to the engine; as well as A controller, comprising at least one processor coupled to at least one memory device storing instructions, which, when executed by the at least one processor, cause the controller to perform operations including: Estimate the aging of the exhaust aftertreatment system; Receive the airspeed passing through the exhaust aftertreatment system; as well as The entry temperature threshold and exit temperature threshold for the thermal management mode of the exhaust aftertreatment system are adjusted based on the airspeed and the aging of the exhaust aftertreatment system, wherein the exit temperature threshold is greater than the entry temperature threshold, and wherein the thermal management mode is activated when the exhaust temperature is at or below the entry temperature threshold, and deactivated when the exhaust temperature is at or above the exit temperature threshold.

2. The system for controlling thermal management modes according to claim 1, wherein, The operation also includes: Based on the airspeed and the aging of the exhaust aftertreatment system, a lookup table is used to adjust at least one of the entry temperature threshold or the exit temperature threshold based on a predefined amount.

3. The system for controlling thermal management modes according to claim 1, wherein, The airspeed is determined using the exhaust flow rate and the dimensions of the exhaust aftertreatment system.

4. The system for controlling thermal management modes according to any one of claims 1-3, wherein, The operation also includes: Determine the amount of NOx output by the system; Compare the system output NOx level with the expected system output NOx level; and The entry temperature threshold or the exit temperature threshold is adjusted based on the comparison.

5. The system for controlling thermal management modes according to any one of claims 1-3, wherein, The thermal management mode includes commands for at least one of the following: cylinder deactivation mode, increased fuel supply, post-injection, change of injection timing, activation of the electric heater in the exhaust aftertreatment system, increase of power output from the engine, actuation of the turbocharger, or change of the position of the intake throttle valve.

6. The system for controlling thermal management modes according to any one of claims 1-3, wherein, Estimating the aging of the exhaust aftertreatment system includes: The aging of the selective catalytic reduction catalyst in a selective catalytic reduction system is estimated based on at least one of the following: (i) time equivalent at a reference temperature, (ii) sulfur content determination, or (iii) the ratio of ammonia to nitrogen oxides. The aging condition of the diesel engine oxidation catalyst is estimated based on at least one of (i) the time equivalent at the reference temperature or (ii) the sulfur content determination; and The aging of the exhaust aftertreatment system is estimated based on at least one of the aging of the selective catalytic reduction catalyst or the aging of the diesel engine oxidation catalyst.

7. A system for controlling a thermal management mode, comprising: A controller includes at least one processor and at least one memory device coupled to the at least one processor, the at least one memory device storing instructions therein, the instructions causing the controller to perform operations including the following when executed by the at least one processor: The estimated cause is the aging of the exhaust aftertreatment system connected to the engine; Receive the airspeed passing through the exhaust aftertreatment system; as well as The entry temperature threshold and exit temperature threshold for the thermal management mode of the exhaust aftertreatment system are adjusted based on the airspeed and the estimated aging of the exhaust aftertreatment system, wherein the thermal management mode is activated when the exhaust temperature is at or below the entry temperature threshold and deactivated when the exhaust temperature is at or above the exit temperature threshold.

8. The system for controlling thermal management modes according to claim 7, wherein, The operation also includes: Based on the airspeed and the aging status of the exhaust aftertreatment system, a lookup table is used to adjust at least one of the entry temperature threshold or the exit temperature threshold based on a predefined amount.

9. The system for controlling thermal management modes according to claim 7, wherein, The airspeed is determined using the exhaust flow rate and the dimensions of the exhaust aftertreatment system.

10. The system for controlling a thermal management mode according to any one of claims 7-9, wherein, The operation also includes: Determine the NOx conversion rate at system output; Compare the system output NOx conversion rate with the expected system output NOx conversion rate; and The entry temperature threshold or the exit temperature threshold is adjusted based on the comparison.

11. The system for controlling a thermal management mode according to any one of claims 7-9, wherein, The thermal management mode includes commands for at least one of the following: cylinder deactivation mode, increased fuel supply, post-injection, change of injection timing, activation of the electric heater in the exhaust aftertreatment system, increase of power output from the engine, actuation of the turbocharger, actuation of the intake bypass valve, actuation of the exhaust bypass valve, actuation of the EGR bypass valve, or change of the position of the intake throttle valve.

12. The system for controlling a thermal management mode according to any one of claims 7-9, wherein, Estimating the aging of the exhaust aftertreatment system includes: The selective catalytic reduction catalyst aging condition of the selective catalytic reduction system is estimated based on at least one of the following: (i) time equivalent at a reference temperature, (ii) sulfur content determination, (iii) ammonia to nitrogen oxide ratio, (iv) duty cycle, or (v) count and duration of active and passive regeneration events. The aging condition of the diesel engine oxidation catalyst is estimated based on at least one of (i) the time equivalent at the reference temperature or (ii) the sulfur content determination; and The aging of the exhaust aftertreatment system is estimated based on at least one of the aging of the selective catalytic reduction catalyst or the aging of the diesel engine oxidation catalyst.

13. A method for controlling a thermal management mode, the method comprising: The estimated cause is the aging of the exhaust aftertreatment system connected to the engine; Receive the airspeed passing through the exhaust aftertreatment system; as well as The entry temperature threshold and exit temperature threshold for the thermal management mode of the exhaust aftertreatment system are adjusted based on the airspeed and the aging of the exhaust aftertreatment system, wherein the thermal management mode is activated when the exhaust temperature is at or below the entry temperature threshold and deactivated when the exhaust temperature is at or above the exit temperature threshold.

14. The method for controlling the thermal management mode according to claim 13, further comprising: Based on the airspeed and the aging status of the exhaust aftertreatment system, a lookup table is used to adjust at least one of the entry temperature threshold or the exit temperature threshold based on a predefined amount.

15. The method for controlling the thermal management mode according to claim 14, wherein, The airspeed is determined using the exhaust flow rate and the dimensions of the exhaust aftertreatment system.

16. The method for controlling the thermal management mode according to any one of claims 13-15, further comprising: Determine the NOx conversion rate at system output; Compare the NOx conversion rate of the system output with the expected NOx conversion rate of the system output; as well as The entry temperature threshold or the exit temperature threshold is adjusted based on the comparison.

17. The method for controlling the thermal management mode according to any one of claims 13-15, wherein, The thermal management mode includes commands for at least one of the following: cylinder deactivation mode, increased fuel supply, post-injection, change of injection timing, activation of the electric heater in the exhaust aftertreatment system, increase of power output from the engine, actuation of the turbocharger, actuation of the intake bypass valve, actuation of the exhaust bypass valve, actuation of the EGR bypass valve, or change of the position of the intake throttle valve.

18. The method for controlling the thermal management mode according to any one of claims 13-15, wherein, Estimating the aging condition of the exhaust aftertreatment system includes: The selective catalytic reduction catalyst aging condition of the selective catalytic reduction system is estimated based on at least one of the following: (i) time equivalent at a reference temperature; (ii) sulfur content determination; (iii) ammonia to nitrogen oxide ratio; (iv) duty cycle determination based on at least one of driving distance, fuel burned, average speed over time, or load; or (v) count and duration of active or passive regeneration events. The aging condition of a diesel engine oxidation catalyst is estimated based on at least one of the following: (i) the time equivalent at the reference temperature, (ii) the sulfur content determination, (iii) the ammonia to nitrogen oxide ratio, (iv) the duty cycle, or (v) the count and duration of active or passive regeneration events; and The aging of the exhaust aftertreatment system is estimated based on at least one of the aging of the selective catalytic reduction catalyst or the aging of the diesel engine oxidation catalyst.

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