Systems and methods for estimating hydrogen in an exhaust gas stream

Abstract

A system includes a controller that is configured to perform operations. The operations include receiving sensor data including information regarding a first water content in an intake gas stream flowing through an intake conduit to an engine and a second water content in an exhaust gas stream flowing through an exhaust conduit from the engine. The operations also include receiving information regarding an air to fuel ratio for the engine. The operations also include estimating, based on the first water content, the second water content, and the air to fuel ratio, a hydrogen content in the exhaust gas stream. The operations also include one of increasing an air to fuel ratio responsive to determining that the hydrogen content is greater than a first threshold; or decreasing the air to fuel ratio responsive to determining that the hydrogen content is less than a second threshold, different than the first threshold.

Description

SYSTEMS AND METHODS FOR ESTIMATING HYDROGENIN AN EXHAUST GAS STREAMCROSS-REFERENCE TO RELATED APPLICATION

[0001] The present application claims the benefit of and priority to U.S. App. No. 63 / 594,770, filed October 31, 2023, which is incorporated herein by reference in its entirety and for all purposes.TECHNICAL FIELD

[0002] The present disclosure relates to systems and methods for estimating hydrogen concentration in an exhaust gas stream of a hydrogen internal combustion engine.BACKGROUND

[0003] It may be desirable to treat exhaust gas produced by a combustion of hydrogen fuel by a hydrogen internal combustion engine (ICE). Unlike internal combustions engines that bum carbonaceous fuel, such as diesel fuel or gasoline, the exhaust produced by a hydrogen internal combustion engine may not include hydrocarbons or carbon oxides (e.g., carbon monoxide or carbon dioxide). Rather, the exhaust gas may include sulfur oxides (SOx) originating from burning lubricants and / or nitrogen oxides (NOx) originating from burning the hydrogen fuel in the presence of air, which may be desirable to be converted to less environmentally harmful elements before emission to the environment.SUMMARY

[0004] One embodiment relates to a system including a controller comprising 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 operations. The operations include receiving information regarding a first water content in an intake gas stream flowing to anengine; receiving information regarding a second water content in an exhaust gas stream flowing from the engine; receiving information regarding an air to fuel ratio for the engine; estimating, based on the first water content, the second water content, and the air to fuel ratio, a hydrogen content in the exhaust gas stream; and one of increasing the air to fuel ratio responsive to determining that the hydrogen content is at or above a first threshold; or decreasing the air to fuel ratio responsive to determining that the hydrogen content is at or below a second threshold, different than the first threshold.

[0005] Another embodiment relates to a method including receiving, by a controller, information regarding an ambient humidity proximate to a system; receiving, by the controller, sensor data comprising information regarding a water content in an exhaust gas stream flowing from an engine of the system; receiving system operational data comprising information regarding an air to fuel ratio; and determining, based on the ambient humidity, the water content, and the air to fuel ratio, a hydrogen content in the exhaust gas stream.

[0006] Yet another embodiment relates to a non-transitory computer readable medium storing instructions that, when executed by one or more processors of a computing system, cause the computing system to perform operations. The operations include receiving information regarding a first water content in an intake gas stream flowing to an engine; receiving information regarding a second water content in an exhaust gas stream flowing from the engine; receiving information regarding an air to fuel ratio for the engine; estimating, based on the first water content, the second water content, and the air to fuel ratio, a hydrogen content in the exhaust gas stream; and adjusting operation of the engine based on comparing the hydrogen content to one or more thresholds.

[0007] Numerous specific details are provided to impart a thorough understanding of embodiments of the subject matter of the present disclosure. The described features of the subject matter of the present disclosure may be combined in any suitable manner in one or more embodiments and / or implementations. In this regard, one or more features of an aspect of the invention may be combined with one or more features of a different aspect of theinvention. Moreover, additional features may be recognized in certain embodiments and / or implementations that may not be present in all embodiments or implementations.BRIEF DESCRIPTION OF THE FIGURES

[0008] FIG. 1 is a block diagram of an engine system, according to an example embodiment.

[0009] FIG. 2 is a block diagram of a controller of the system of FIG. 1, according to an example embodiment.

[0010] FIG. 3 is a flow diagram of a method of estimating hydrogen content in exhaust gas from the engine of the system of FIG. 1, according to an example embodiment.

[0011] FIG. 4 is a graph depicting a relationship between hydrogen content and water content, according to an example embodiment.DETAILED DESCRIPTION

[0012] Following below are more detailed descriptions of various concepts related to, and implementations of, methods, apparatuses, and systems for estimating or otherwise determining hydrogen content in an exhaust gas stream from a hydrogen internal combustion engine. Before turning to the Figures, which illustrate certain exemplary embodiments in detail, it should be understood that the present disclosure is not limited to the details or methodology set forth in the description or illustrated in the Figures. It should also be understood that the terminology used herein is for the purpose of description only and should not be regarded as limiting.

[0013] As utilized herein, the term “content” and like terms are used to refer to an amount of a substance within a mixture. The amount may be expressed as a value, such as a mass value (e.g., measured in grams, kilograms, etc.), a weight value (e.g., measured in ounces, pounds, etc.), or another suitable value, such as a molar value. In some embodiments, the amount may be expressed as a concentration (e.g., an amount of a substance divided by the total amount of a mixture), such as parts per million, percent weight, percent mass, molar concentration,volumetric concentration, and so on. For example, a hydrogen content in a gas stream may be a mass of the hydrogen, a concentration of hydrogen relative to the gas stream, a percentage of hydrogen by weight relative to the weight of the gas stream, etc. In another example, a water content in a gas stream may be a mass of the water, a concentration of water relative to the gas stream, a percentage of water by weight relative to the gas stream, etc.

[0014] As utilized herein, the term “estimating” and like terms are used to refer to determining a current or past value that is not a measured value, such as measurements from a real sensor (e.g., a temperature measured by a temperature sensor). In other words, estimation refers to an approximation of a value(s) that may differ from an actual or measured value. Estimating a current or past value may be based on information from a real sensor (e.g., sensor data, historical sensor data, real-time sensor data, etc.) or information from another source. In some embodiments, estimating the current or past value can be performed using one or more models (e.g., statistical models, artificial intelligence models, machine learning models, etc.). For example, estimating a hydrogen content can include using data, such as sensor data, with a model to determine the hydrogen content.

[0015] As utilized herein, the term “operational data” and like terms are used to refer to data regarding the operation of a system, such as an engine system. In some embodiments, operational data may include settings, values, or other information regarding the operation of a system. For example, operational data of an engine system may include a ratio of an amount of air relative to an amount of fuel provided to the engine for combustion (referred to herein as an “air to fuel ratio”). In some embodiments, the operational data may be measured (e.g., by one or more real sensors) or estimated (e.g., by one or more virtual sensors or by a computer device or processing circuit).

[0016] According to the various embodiments described herein, a gas stream may be an intake gas stream, an exhaust gas stream, or both. An intake gas stream is a gas stream that enters an engine system (e.g., via an inlet). An exhaust gas stream is a gas stream that is output by an engine and / or received at an inlet of the aftertreatment system.

[0017] As described herein, an engine system may include an engine and an exhaust aftertreatment system in exhaust gas receiving communication with the engine. The exhaust aftertreatment system may include one or more components, such as a particulate filter configured to remove particulate matter, such as soot, from exhaust gas flowing in the exhaust gas conduit system, a dosing module (e.g., a doser) configured to supply a dosing fluid to the exhaust gas flowing in the aftertreatment system, and one or more catalyst devices configured to facilitate conversion of the exhaust gas constituents (e.g., nitrogen oxides, NOx, sulfur oxides, SOX, etc.) to less harmful elements (e.g., water, nitrogen, N2, etc.), such as an oxidation catalyst, a selectively catalytic reduction (SCR) system, a three-way catalyst, and so on. A control system or controller may monitor one or more parameters of the components of the engine system using one or more sensors (e.g., actual sensors and / or virtual sensors) to collect and / or determine sensor data. In particular, the sensor data may include a water content within an exhaust gas stream. The control system may use the sensor data with one or more models, lookup tables, etc. to determine estimated data. In particular, the control system may use the sensor data with one or more models, lookup tables, etc. to determine a hydrogen content within the exhaust gas stream.

[0018] Technically and beneficially, the systems, methods, and apparatuses described herein provide an improved control system that uses sensor data to estimate a hydrogen content within an exhaust gas stream. Measuring hydrogen content directly (e.g., via a hydrogen sensor) downstream of a hydrogen internal combustion engine poses technical problems. For example, a typical hydrogen sensor may be designed for relatively lower temperature environments, such as ambient conditions or hydrogen fuel cell applications. Therefore, typical hydrogen sensors may be not suited for positioning downstream of a hydrogen internal combustion engine due to the elevated temperatures. Furthermore, typical hydrogen sensors may be expensive to implement and maintain. Due to the conditions downstream of a hydrogen internal combustion engine, sensors downstream of the hydrogen internal combustion engine may require relatively high durability requirements (compared to ambient condition applications) to aid with complying with various emissions standards, which may increase upfront costs and / or operating costs. The systems, computer-readable media, and methods described herein advantageously estimate thehydrogen content without directly measuring the hydrogen content (e.g., via a sensor). The systems, computer-readable media, and methods described herein provide a relatively accurate, low-cost, reliable, and durable process of estimating the hydrogen content in the exhaust gas stream. That is, the systems, computer-readable media, and methods described herein provide a technical solution to the technical problem of estimating a hydrogen content within an exhaust gas stream without measuring the hydrogen content directly via a sensor.

[0019] It may be desirable to acquire an accurate estimation of the unbumed hydrogen (H2) gas in an exhaust gas stream of a hydrogen fueled internal combustion engine. In some embodiments, an estimation of unburned H2 (e.g., a hydrogen content in the exhaust gas stream) may be used to understand the combustion, performance, and / or emissions (CPE) status of the engine. In some embodiments, the estimation of the hydrogen content in the exhaust gas stream may be used for aftertreatment thermal management optimization. In some embodiments, the estimation of the hydrogen content in the exhaust gas stream may be used to calibrate one or more sensors in the aftertreatment system.

[0020] In an example embodiment, the engine system includes a hydrogen fueled internal combustion engine. The system includes a humidity sensor disposed in the exhaust manifold, where condensation is not expected to accumulate (e.g., upstream of a turbo device, such as a turbocharger). The system includes a controller configured to measure and / or monitor an air to fuel ratio (AFR) via one or more sensors (e.g., oxygen sensors) that are disposed in one or more of the intake and / or exhaust manifolds. For example, the system may include an oxygen sensor (e.g., a narrow-band oxygen sensor, a wide-band oxygen sensor, and / or other suitable sensor) positioned at or near the exhaust manifold. The controller is configured to estimate the AFR based on an oxygen content detected by the oxygen sensor. For example, the controller may estimate the AFR based on the oxygen content and a known or expected combustion efficiency of the engine. More specifically, the controller may estimate the AFR using one or more models (e.g., mathematical or physics-based models) that correlate the oxygen content and a known or expected combustion efficiency of the engine with the AFR. In another example embodiment, a method of estimating hydrogen content in the exhaust gas stream may include receiving dataregarding an AFR and sensor data regarding a water content in the exhaust gas stream (e.g., an exhaust humidity reading) and estimating the hydrogen content in the exhaust gas stream based on a relationship (e.g., correlation) between the AFR, the water content in the exhaust gas stream, and the hydrogen content in the exhaust gas stream.

[0021] In an example scenario, a control system (e.g., a controller, a vehicle controller, etc.) utilizes one or more sensors (e.g., real sensors and / or virtual sensors) to acquire sensor data regarding a water content in a gas stream. As briefly described above, a gas stream may be an intake gas stream that enters the engine system via an inlet, an exhaust gas stream that is output by the engine or received at an inlet of the aftertreatment system, or both an intake gas stream and an exhaust gas stream. The intake gas stream may include air, water (e.g., vapor), and other gases present in the ambient surroundings of the engine system. The exhaust gas stream may include air, water (e.g., vapor), hydrogen, nitrogen oxides, sulfur oxides, and / or other gases output by the engine. The control system may estimate a hydrogen content in the exhaust gas stream based on the sensor data (e.g., the water content in the intake gas stream and / or the water content in the exhaust gas stream). In some embodiments, the control system may estimate the hydrogen content based on the sensor data and one or more models (e.g., machine learning models, statistical models, etc.). In some embodiments, the control system may estimate the hydrogen content based on a known air to fuel ratio (e.g., an amount of air relative to an amount of fuel provided to the combustion cylinders of the engine, also referred to herein as “AFR”). Using this estimate, the control system may implement one or more actions with the system. For example, the control system may control (e.g., increase, decrease or maintain) the AFR based on the estimated hydrogen content. Beneficially, this may result in a controlled amount of hydrogen in the aftertreatment system, such that the hydrogen content in the aftertreatment system is within a desired range (e.g., above a minimum threshold and / or below a maximum threshold). These and other features and benefits are described herein below.

[0022] Referring now to FIG. 1, a schematic view of a block diagram of an engine system 100 is shown, according to an example embodiment. The engine system 100 includes an engine 102 and an aftertreatment system 120 in exhaust gas receiving communication with the engine 102.The system 100 may also include a controller 140 (as shown in FIG. 2) and an operator input / output (I / O) device 130, where the controller 140 is communicably coupled to each of the aforementioned components. In some embodiments, the engine system 100 also includes a turbo device 122 disposed between the engine 102 and the aftertreatment system 120, such that the turbo device 122 is in exhaust gas receiving communication with the engine 102 and exhaust gas providing communication with the aftertreatment system 120. In these embodiments, the aftertreatment system 120 is in exhaust gas receiving communication with the engine 102 (e.g., via the turbo device 122).

[0023] In the configuration of FIG. 1, the engine system 100 is included in a vehicle. The vehicle may be any type of on-road or off-road vehicle including, but not limited to, wheel-loaders, forklift trucks, line-haul trucks, mid-range trucks (e.g., pick-up truck, etc.), sedans, coupes, tanks, airplanes, boats, and any other type of vehicle. In another embodiment, the engine system 100 may be embodied in a stationary piece of equipment, such as a power generator or genset. All such variations are intended to fall within the scope of the present disclosure.

[0024] In the configuration shown in FIG. 1, the engine 102 is a hydrogen internal combustion engine (ICE). The hydrogen ICE may consume hydrogen fuel to generate power. In other embodiments, the engine 102 may be part of a hybrid engine system having a combination of an internal combustion engine and at least one electric motor coupled to at least one battery. In some embodiments, the hybrid engine system may be configured as a mild-hybrid powertrain, a parallel hybrid powertrain, a series hybrid powertrain, or a series-parallel powertrain.

[0025] The engine 102 includes one or more cylinders 104 (e.g., combustion cylinder). Each cylinder 104 has a corresponding igniter 106 (e.g., spark plug, glow plug, etc.). The igniter 106 is configured to ignite fuel (e.g., hydrogen) within a corresponding cylinder 104. As shown in FIG. 1, the engine 102 includes six cylinders 104. However, it should be understood that the engine 102 may include more or fewer cylinders 104 (e.g., at least one) than as shown in FIG. 1. Furthermore, the cylinders 104 may be provided in varying arrangements, (e.g., in-line, horizontal, V, or other suitable cylinder arrangement).

[0026] The engine system 100 includes an intake conduit 110 and an intake manifold 112. The intake conduit 110 is configured to route an intake gas stream, including air (e.g., ambient air), to the intake manifold 112. The intake manifold 112 is configured to route the intake gas stream from an intake conduit 110 into the engine 102. More specifically, the intake manifold 112 is configured to route air from the intake conduit 110 into each of the cylinders 104.

[0027] The engine system 100 includes an intake air throttle (IAT) valve 114. The IAT valve 114 is disposed at the intake conduit 110 and upstream of the intake manifold 112. The IAT valve 114 is structured to control an amount of air supplied to the engine 102. The IAT valve 114 may be actuated (e.g., by an actuator controlled by the controller 140) between an open position and a closed position. In the open position, the IAT valve 114 allows a maximum amount of air to flow from the air intake to the engine 102. In the closed position, the IAT valve 114 allows a minimum amount of air to flow from the air intake to the engine 102. The controller 140 may selectively actuate the IAT valve 114 (e.g., by controlling the actuator) in a plurality of positions between and / or including the open position and the closed position to adjust the amount of air received by the engine 102. In some embodiments, the IAT valve 114 is operable to control an amount and / or timing of air provided to the engine 102 to achieve a target air to fuel ratio (AFR). For example, the controller 140 may control the IAT valve 114 to adjust an amount of air provided to the engine 102 relative to an amount of fuel provided to the engine 102.

[0028] The engine system 100 includes an exhaust manifold 116 and an exhaust conduit 118. The exhaust manifold 116 is configured to route an exhaust gas stream from the engine to the exhaust conduit 118. More specifically, the exhaust manifold 116 is configured to route an exhaust gas stream from each of the cylinders 104 to the exhaust conduit 118. The exhaust conduit 118 is configured to route the exhaust gas stream from the exhaust manifold 116 to a downstream component, such as the aftertreatment system 120 and / or the turbo device 122. In some embodiments, a first portion of the exhaust conduit 118 is disposed between the exhaust manifold 116 and turbo device 122. The first portion of the exhaust conduit 118 is configured to route the exhaust gas stream from the exhaust manifold 116 to turbo device 122. In some embodiments, a second portion of the exhaust conduit 118 is disposed between the turbo device122. The second portion of the exhaust conduit 118 is configured to route the exhaust gas stream from the turbo device 122 to the aftertreatment system 120.

[0029] The aftertreatment system 120 is in exhaust gas receiving communication with the engine 102. The aftertreatment 120 system includes components used to reduce exhaust emissions, such as a selective catalytic reduction (SCR) catalyst, an oxidation catalyst (DOC), a particulate filter (DPF), an exhaust fluid doser with a supply of exhaust fluid, a plurality of sensors for monitoring the aftertreatment system (e.g., a nitrogen oxide (NOx) sensor, temperature sensors, etc.), and / or still other components.

[0030] The turbo device 122 may be any type of turbo machinery, such as a turbocharger, a supercharger, a variable geometry turbocharger, a power turbine, etc. The turbo device 122 may be operatively coupled to the engine 102 and / or another component of the engine system 100, such as a drivetrain, a battery, an electric machine, or other suitable component.

[0031] The engine system 100 also includes a fuel system 124. The fuel system 124 is configured to provide fuel (e.g., hydrogen) to the engine 102. More specifically, the fuel system 124 is configured to provide fuel to each of the one or more cylinders 104. The fuel system 124 may include one or more components for providing the fuel to the engine 102, such as a storage tank for storing the fuel, one or more regulators (e.g., valves, solenoids, etc.) for controlling an amount or a timing of fuel provided to the engine 102, and / or a fuel injector. In some embodiments, the fuel injector is provided at the intake manifold 112. In other embodiments, the fuel system 124 includes a separate fuel injector for each cylinder 104 such that the fuel system 124 directly injects the fuel into each of the cylinders 104.

[0032] In some embodiments, the controller 140 is operatively coupled to the fuel system 124 such that the controller 140 may control the operation of the fuel system 124. More specifically, the controller 140 may control the fuel system 124 to control an amount and / or a timing of fuel provided to the engine 102. In some embodiments, the fuel system 124 is operable to control an amount and / or timing of fuel provided to the engine 102 to achieve a target AFR. For example,the controller 140 may control the fuel system 124 to adjust an amount of fuel provided to the engine 102 relative to an amount of air provided to the engine 102.

[0033] As shown, a plurality of sensors 125 are included in the engine system 100. The number, placement, and type of sensors included in the engine system 100 is shown for example purposes only. That is, in other configurations, the number, placement, and type of sensors may differ. The sensors 125 may be gas constituent sensors (e.g., NOx sensors, oxygen sensors, H2O / humidity sensors, etc.), temperature sensors, particulate matter (PM) sensors, flow rate sensors (e.g., mass flow rate sensors, volumetric flow rate sensors, etc.), other exhaust gas emissions constituent sensors, pressure sensors, some combination thereof, and so on. The gas constituent sensors may include an FhO / humidity sensor that is structured to acquire data indicative of the presence of water in a gas stream (e.g., a water content). The data from the H2O / humidity sensor may be used to estimate a hydrogen content in the exhaust gas stream.

[0034] As shown in FIG. 1, the sensors 125 may be located at or proximate the intake conduit 110, the intake manifold 112, the exhaust manifold 116, and the exhaust conduit 118. It should be understood that the location of the sensors may vary, and the engine system 100 may include more or fewer sensors than as shown in FIG. 1. In one embodiment, the engine system 100 may include sensors 125 located both before and after the aftertreatment system 120.

[0035] Additional sensors may be also included with the system 100. The sensors may include engine-related sensors (e.g., torque sensors, speed sensors, pressure sensors, flowrate sensors, temperature sensors, etc.). The sensors may further include sensors associated with other components of the vehicle, such as the aftertreatment system 120, the turbo device 122, or the fuel system 124. For example, the sensor may include speed sensor of the turbo device 122, a fuel quantity and injection rate sensor, fuel rail pressure sensor, etc.).

[0036] The sensors 125 may be real or virtual (i.e., a non-physical sensor that is structured as program logic in the controller 140 that makes various estimations or determinations). For example, an engine speed sensor may be a real or virtual sensor arranged to measure orotherwise acquire data, values, or information indicative of a speed of the engine 102 (typically expressed in revolutions-per-minute). The sensor is coupled to the engine 102 (when structured as a real sensor) and is structured to send a signal to the controller 140 indicative of the speed of the engine 102. When structured as a virtual sensor, at least one input may be used by the controller 140 in an algorithm, model, lookup table, etc. to determine or estimate a parameter of the engine (e.g., power output, etc.). Any of the sensors 125 described herein may be real or virtual.

[0037] The controller 140 is coupled, and particularly communicably coupled, to the sensors 125. Accordingly, the controller 140 is structured to receive data from one more of the sensors 125 and provide instructions / information to the one or more sensors 125. The controller 140 may use the received data to control one more components in the system 100 and / or for monitoring and / or hydrogen content estimating purposes.

[0038] The operator input / output (I / O) 130 device may be coupled to the controller 140, such that information may be exchanged between the controller 140 and the I / O device 130, where the information may relate to one or more components of FIG. 1 or determinations (described below) of the controller 140. The operator i / o device 130 enables an operator of the system 100 to communicate with the controller 140 and one or more components of the system 100 of FIG.1. For example, the operator input / output device 130 may include, but is not limited to, an interactive display, a touchscreen device, one or more buttons and switches, voice command receivers, etc. In this way, the operator input / output device 130 may provide one or more indications or notifications to an operator, such as a malfunction indicator lamp (MIL), etc. Additionally, the vehicle may include a port that enables the controller 140 to connect or couple to a scan tool so that fault codes and other information regarding the vehicle may be obtained.

[0039] The controller 140 is structured to control, at least partly, the operation of the system 100 and associated sub-systems, such as the engine 102 and the operator I / O device 130. Communication between and among the components may be via any number of wired or wireless connections. For example, a wired connection may include a serial cable, a fiber opticcable, a CAT5 cable, or any other form of wired connection. In comparison, a wireless connection may include the Internet, Wi-Fi, cellular, radio, etc. In one embodiment, a controller 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 the controller 140 is communicably coupled to the systems and components of FIG. 1, the controller 140 is structured to receive data from one or more of the components shown in FIG. 1. The structure and function of the controller 140 is further described in regard to FIG. 2.

[0040] As the components of FIG. 1 are shown to be embodied in the system 100, the controller 140 may be structured as one or more electronic control units (ECUs), such as one or more microcontrollers. The controller 140 may be separate from or included with at least one of a transmission control unit, an exhaust aftertreatment control unit, a powertrain control module, an engine control unit, an engine control module, etc.

[0041] Now referring to FIG. 2, a schematic diagram of the controller 140 of the system 100 of FIG. 1 is shown, according to an example embodiment. As shown, the controller 140 includes at least one processing circuit 202 having at least one processor 204 and at least one memory device 206, a hydrogen estimation circuit 210, and a communications interface 216. The controller 140 is structured to determine, and particularly estimate, a hydrogen content in an exhaust gas stream. The estimated hydrogen content may be based on an air to fuel ratio, a water content of an intake gas stream, and / or a water content of the exhaust gas stream. Specific processes for estimating the hydrogen content in the exhaust gas stream are described herein below.

[0042] In one configuration, the hydrogen estimation circuit 210 is embodied as instructions that are executable by a processor, such as processor 204. As described herein and amongst other uses, the instructions facilitate performance of certain operations to enable reception and transmission of data. For example, the machine-readable media may provide an instruction (e.g., command, etc.) to, e.g., acquire data. In this regard, the machine-readable media may include programmable logic that defines the frequency of acquisition of the data (or, transmission of thedata). The computer readable media instructions may include code, which may be written in any programming language including, but not limited to, Java or the like and any conventional procedural programming languages, such as the "C" programming language or similar programming languages. The computer readable program code may be executed on one processor or multiple remote processors. In the latter scenario, the remote processors may be connected to each other through any type of network (e.g., CAN bus, etc.).

[0043] In another configuration, the hydrogen estimation circuit 210 is embodied as a hardware unit, such as one or more electronic control units. As such, the hydrogen estimation circuit 210 may be embodied as one or more circuitry components including, but not limited to, processing circuitry, network interfaces, peripheral devices, input devices, output devices, etc. In some embodiments, the hydrogen estimation circuit 210 may take the form of one or more analog circuits, electronic circuits (e.g., integrated circuits (IC), discrete circuits, system on a chip (SOCs) circuit, microcontrollers, etc.), telecommunication circuits, hybrid circuits, and any other type of “circuit.” In this regard, the hydrogen estimation circuit 210 may include any type of component for accomplishing or facilitating achievement of the operations described herein. For example, a circuit as 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, and so on. The hydrogen estimation circuit 210 may also include or be programmable hardware devices such as field programmable gate arrays, programmable array logic, programmable logic devices or the like. The hydrogen estimation circuit 210 may include one or more memory devices for storing instructions that are executable by the processor(s) of the hydrogen estimation circuit 210. The one or more memory devices and processor(s) may have the same definition as provided below with respect to the memory device 206 and processor 204. In some hardware unit configurations, the hydrogen estimation circuit 210 may be geographically dispersed throughout separate locations in the vehicle. Alternatively, and as shown, hydrogen estimation circuit 210 may be embodied in or within a single unit / housing, which is shown as the controller 140.

[0044] In the example shown, the controller 140 includes the processing circuit 202 having the processor 204 and the memory device 206. The processing circuit 202 may be structured or configured to execute or implement the instructions, commands, and / or control processes described herein with respect to the hydrogen estimation circuit 210. The depicted configuration represents the hydrogen estimation circuit 210 as being embodied as machine or computer- readable media. In some embodiments, the instructions may be included with the memory device 206. However, as mentioned above, this illustration is not meant to be limiting as the present disclosure contemplates other embodiments where the hydrogen estimation circuit 210, is configured as a hardware unit. All such combinations and variations are intended to fall within the scope of the present disclosure.

[0045] The processor 204 may be implemented as one or more single- or multi-chip processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), and / or suitable processors (e.g., other programmable logic devices, discrete hardware components, etc. to perform the functions described herein). A processor may be a microprocessor, a group of processors, etc. A processor also may be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. In some embodiments, the one or more processors may be shared by multiple circuits (e.g., the hydrogen estimation circuit 210 may comprise or otherwise share the same processor which, in some example embodiments, may execute instructions stored, or otherwise accessed, via different areas of memory). Alternatively or additionally, the one or more processors may be structured to perform or otherwise execute certain operations independent of one or more co-processors. In other example embodiments, two or more processors may be coupled via a bus to enable independent, parallel, pipelined, or multi -threaded instruction execution. All such variations are intended to fall within the scope of the present disclosure.

[0046] The memory device 206 (e.g., memory, memory unit, storage device) may include one or more devices (e.g., RAM, ROM, Flash memory, hard disk storage) for storing data and / orcomputer code for completing or facilitating the various processes, layers and modules described in the present disclosure. For example, the memory device 206 may include dynamic randomaccess memory (DRAM). The memory device 206 may be communicably connected to the processor 204 to provide computer code or instructions to the processor 204 for executing at least some of the processes described herein. Moreover, the memory device 206 may be or include tangible, non-transient volatile memory or non-volatile memory. Accordingly, the memory device 206 may include database components, object code components, script components, or any other type of information structure for supporting the various activities and information structures described herein.

[0047] The communications interface 216 may include any combination of wired and / or wireless interfaces (e.g., jacks, antennas, transmitters, receivers, transceivers, wire terminals) for conducting data communications with various systems, devices, or networks structured to enable in-vehicle communications (e.g., between and among the components of the vehicle) and out-of- vehicle communications (e.g., with a remote server). For example, and regarding out-of- vehicle / system communications, the communications interface 216 may include an Ethernet card and port for sending and receiving data via an Ethernet-based communications network and / or a Wi-Fi transceiver for communicating via a wireless communications network.The communications interface 216 may be structured to communicate via local area networks or wide area networks (e.g., the Internet) and may use a variety of communications protocols (e.g., IP, LON, Bluetooth, ZigBee, radio, cellular, near field communication).

[0048] As shown in FIG. 2, the communications interface 216 may enable communication with the engine 102, the aftertreatment system 120 (and / or a component thereof), the one or more sensors 125, the IAT valve 114, and / or the fuel system 124.

[0049] The hydrogen estimation circuit 210 is structured to estimate a hydrogen content of an exhaust gas stream. In some embodiments, the hydrogen estimation circuit 210 is structured to receive sensor data (e.g., from the sensors 125).

[0050] The sensor data may include a water content in an intake gas stream. In some embodiments, the water content in the intake gas stream may be measured by a sensor 125 (e.g., a water sensor, a humidity sensor, etc.) positioned at the intake conduit 110, the intake manifold 112, or another location upstream of the engine 102. In some embodiments, the water content in the intake gas stream may be estimated (e.g., by the controller 140 and / or by a virtual humidity sensor 125). For example, the water content in the intake gas stream may be equivalent to and / or estimated based on an ambient humidity (e.g., via a lookup table that correlates ambient humidity to water content in particular locations, which may be based on experimental data for various ambient humidities at various operating conditions of the engine 102, such as temperature zones). In some embodiments, the ambient humidity may be measured by an ambient humidity sensor. In other embodiments, the ambient humidity may be received (e.g., by the controller 140, via the communications interface 216) from an external computing system (e.g., from a weather reporting service, etc.).

[0051] In some embodiments, the hydrogen estimation circuit 210 is structured to receive information regarding the ambient humidity proximate the system 100 from a remote computing system (e.g., a computing system that is located remotely from the system 100). The information regarding the ambient humidity may include a water content value, a relative humidity value, an ambient temperature value, and / or other information regarding the ambient humidity proximate the system 100. In this way, the water content in the intake gas stream may include or be based on the information regarding the ambient humidity.

[0052] The sensor data may include a water content in an exhaust gas stream. In some embodiments, the hydrogen estimation circuit 210 may determine the water content in the exhaust gas stream based on one or more sensor readings. In some embodiments, the water content in the exhaust gas stream may be measured by a sensor (e.g., a water sensor, a humidity sensor, etc.) positioned at the exhaust manifold 116, the exhaust conduit 118, or another location downstream of the engine 102. In these embodiments, the sensor may be positioned upstream of the aftertreatment system 120 and, in particular, upstream of the turbo device 122.

[0053] In some embodiments, the hydrogen estimation circuit 210 is structured to receive system operational data. The system operational data may include information regarding the operation of the system 100. For example, the system operational data may include an air to fuel ratio. In some embodiments, the AFR is a target AFR (e.g., an AFR commanded by the controller 140). In other embodiments, the AFR is a measured AFR (e.g., an AFR measured and / or estimated by one or more sensors 125, such as a lambda sensor). For example, one or more sensors 125, such as an oxygen sensor, may be disposed at or in the intake manifold 112 and / or the exhaust manifold 116. The oxygen sensor may acquire data regarding an oxygen content in the intake gas stream and / or in the exhaust gas stream. The controller 140 and / or one or more components thereof (e.g., the hydrogen estimation circuit 210) is structured to determine the AFR value based on the oxygen content in the intake gas stream and / or in the exhaust gas stream. For example, the controller 140 may use one or more of a lookup table or a model that correlates the oxygen content in the intake gas stream and / or in the exhaust gas stream to the AFR value, which may be based on experimental data for various oxygen content values at various operating conditions of the engine 102, such as temperature zones, fuel injection amount, fuel injection timing, and so on.

[0054] In some embodiments, the hydrogen estimation circuit 210 is structured to estimate the hydrogen content in the exhaust gas stream based on one or more of the water content in the intake gas stream, the water content in the exhaust gas stream, and / or the AFR. For example, the hydrogen estimation circuit 210 may use one or more models (e.g., a statistical model, a mathematical model, a machine learning model, etc.) or a look-up table to estimate to estimate the hydrogen content in the exhaust gas stream. More specifically, the one or more models and / or the look-up tables may corelate an exhaust gas stream water content with an exhaust gas stream hydrogen content. The one or more models and / or the look-up table(s) may be based on experimental data for various hydrogen content values at various operating conditions of the engine 102, such various AFR values and / or various water content values regarding the intake gas stream or the exhaust gas stream. In some embodiments, the correlation between the water content of the exhaust gas stream and the hydrogen content of the exhaust gas stream is based ona predetermined or known ambient humidity (e.g., the water content of the intake gas stream) and a known AFR. In this way, the hydrogen estimation circuit 210 may estimate the hydrogen content in the exhaust gas stream based on a water content in the exhaust gas stream, the water content in an intake gas stream (e.g., an ambient humidity), and an AFR.

[0055] In an example embodiment, the hydrogen estimation circuit 210 is structured to estimate the hydrogen content in the exhaust gas stream based on an expected amount of water in the exhaust gas stream. The expected water content in the exhaust gas stream may be based on the combustion of hydrogen, as shown in Equation 1 below, the AFR, and the ambient humidity. As shown in Equation 1, the ratio of hydrogen input to the engine 102 to water output by the engine 102 is one to one (1 : 1). Accordingly, the expected water content in the exhaust gas stream may be determined based on a summation of the hydrogen input to the engine 102 (e.g., based on the AFR), which is equivalent or assumed to be equivalent to the water output by the engine 102 due to combustion of the hydrogen fuel, and a water content in the intake gas stream (e.g., an ambient humidity).

[0056] 2H2+ O2+ 3.77N2-> 2HZO + 3.77N2(1)

[0057] The hydrogen estimation circuit 210 is structured estimate the hydrogen content in the exhaust gas stream based on an expected water content in the exhaust gas stream compared to a measured water content in the exhaust gas stream. More specifically, a difference between the expected water content in the exhaust gas stream and the measured water content in the exhaust gas stream is equal or assumed to be equal to the hydrogen content in the exhaust gas stream.

[0058] In some embodiments, the controller 140 is structured to adjust the operation of the engine 102 (or other components of the system 100) based on the hydrogen content in the exhaust gas stream. For example, the controller 140 may be structured to adjust the AFR based on the hydrogen content in the exhaust gas stream. In some embodiments, the controller 140 may increase the AFR by increasing an amount of air provided to the engine 102 by operating the IAT valve 114. For example, the controller 140 may cause the IAT valve 114 to actuate to aposition closer to or at a fully open position and / or to remain in the open position for a relatively longer duration to allow more air to flow into the engine 102. In some embodiments, the controller 140 may increase the AFR by decreasing an amount of fuel provided to the engine 102 by controlling the fuel system 124. For example, the controller 140 may cause one or more components of the fuel system 124, such as a fuel valve and / or a fuel injector, to reduce an amount of fuel to provide to the engine 102.

[0059] In some embodiments, the controller 140 may decrease the AFR by decreasing an amount of air provided to the engine 102 by operating the IAT valve 114. For example, the controller 140 may cause the IAT valve 114 to actuate to a position closer to or at a fully closed position and / or to remain in the closed position for a relatively longer duration to allow less air to flow into the engine 102. In some embodiments, the controller 140 may decrease the AFR by increasing an amount of fuel provided to the engine 102 by controlling the fuel system 124. For example, the controller 140 may cause one or more components of the fuel system 124, such as a fuel valve and / or a fuel injector, to increase an amount of fuel provided to the engine 102.

[0060] In some embodiments, the controller 140 may increase the AFR responsive to determining that the hydrogen content in the exhaust gas stream is greater than a first threshold. Increasing the AFR may result in, for example, a decrease in the concentration of hydrogen (e.g., relative to the concentration of air) in the engine 102, which, in turn, may result in a decrease in the concentration of hydrogen in the exhaust gas stream. In some embodiments, the controller 140 may decrease the AFR responsive to determining that the hydrogen content in the exhaust gas stream is less than a second threshold, different than the first threshold. Decreasing the AFR may result in, for example, an increase in the concentration of hydrogen (e.g., relative to the concentration of air) in the engine 102, which, in turn, may results in an increase in the concentration of hydrogen in the exhaust gas stream.

[0061] In some embodiments, the controller 140 may determine a “state of health” of one or more components of the engine system 100, based on the hydrogen content in the exhaust gas stream. As used herein a “state of health” of a component refers to a measurement of acomponent’s performance. For example, the state of health of a component may include a hydrogen content of an exhaust gas stream that corresponds to the component relative to a hydrogen content threshold. More specifically, the state of health of the engine 102 (or a component thereof) may include a hydrogen content of the exhaust gas stream at an outlet of the engine relative to an engine exhaust hydrogen content threshold. In one example, the controller 140 may determine that a component of the engine 102, such as a cylinder(s) 104 or an igniter(s) 106 has failed based on the hydrogen content in the exhaust gas stream exceeding a predetermined threshold. More specifically, the controller 140 may determine that the cylinder 104 is leaking fuel and / or that the igniter 106 is not properly igniting the fuel based on the hydrogen content value exceeding the predetermined threshold. In an example embodiment, determining the state of health of the engine 102 includes comparing the hydrogen content to an engine exhaust hydrogen content threshold. The controller 140 may determine that a component of the engine 102 has failed or has likely failed based on the hydrogen content exceeding a predetermined threshold.

[0062] In another example, the state of health of the fuel system 124 may include a hydrogen content at or proximate an outlet of the fuel system 124, or at or proximate an inlet of the engine 102 relative to an engine inlet hydrogen content threshold. In some embodiments, the controller 140 may determine that a component has failed or has likely failed based on a hydrogen content value (e.g., a hydrogen content at proximate the engine in the exhaust gas stream, etc.) exceeding a predetermined threshold. For example, the controller 140 may determine that a fuel injector of the fuel system 124 has failed based on the hydrogen content at or proximate an outlet of the fuel system 124, at or proximate an inlet of the engine 102, in the exhaust gas stream exceeding a predetermined threshold. More specifically, the controller 140 may determine that the fuel injector of the fuel system 124 is leaking hydrogen based on the hydrogen content value exceeding the predetermined threshold. In an example embodiment, determining the state of health of the fuel system includes receiving information regarding a hydrogen content value proximate an inlet of the engine 102 (e.g., a second hydrogen content value). The controller 140 then compares the second hydrogen content value to an engine inlet hydrogen content threshold.The controller 140 may determine that a component of the fuel system has failed or has likely failed based on the second hydrogen content value exceeding a predetermined threshold.

[0063] In some embodiments, the controller 140 may determine a state of health of one or more components of the system 100, such as at least one of the engine 102 or the fuel system 124. The controller 140 may provide an engine status notification to the operator input / output device 130, where the engine status notification includes the state of health (e.g., in text format, such as a value, a description, or other text and / or as an image, graph, or other depiction).

[0064] In some embodiments, responsive to determining that the hydrogen content in the exhaust gas stream exceeds the predetermined threshold, the controller 140 may activate a fault code (e.g., malfunction indicator lamp, light / lamp on a display device, etc.). The fault code may indicate that the hydrogen content in the exhaust gas stream exceeds the predetermined threshold. Additionally and / or alternatively, the controller 140 may perform one or more corrective actions responsive to determining that the hydrogen content in the exhaust gas stream exceeds the predetermined threshold. In some embodiments, the corrective actions may include adjusting an AFR (e.g., by increasing or decreasing a fueling amount and / or by increasing or decreasing an amount of air provided to the engine 102). In some embodiments, the corrective actions may include adjusting an ignition event by adjusting the operation of the igniter 106 (e.g., increasing an ignition energy, decreasing an ignition energy, adjusting an ignition timing, etc.).

[0065] In some embodiments, the controller 140 may calibrate one or more sensors 125 based on the hydrogen content in the exhaust gas stream. In these embodiments, the sensors 125 may include an oxygen sensor (e.g., a sensor configured to acquire data regarding an oxygen content in a gas stream), a nitrogen oxide sensor (e.g., a sensor configured to acquire data regarding a nitrogen oxide content in a gas stream), and / or or other sensor configured to acquire data regarding a content of a gas constituent in a gas stream. The sensors 125 may be disposed downstream of the engine 102 (e.g., at or in the exhaust conduit 118 or the aftertreatment system 120). The sensors 125 may be cross-sensitive to hydrogen. That is, the sensors 125 can acquire data regarding the hydrogen content in a gas stream. The controller 140 may calibrate one ormore sensors 125 based on the hydrogen content in the exhaust gas stream. For example, if the estimated hydrogen content in the exhaust gas stream is greater than a measured hydrogen content in the exhaust gas stream, the controller 140 may cause the sensors 125 to report greater values based on acquired data regarding the hydrogen content in the exhaust gas stream. Similarly, if the estimated hydrogen content in the exhaust gas stream is less than a measured hydrogen content in the exhaust gas stream, the controller 140 may cause the sensors 125 to report smaller values based on acquired data regarding the hydrogen content in the exhaust gas stream.

[0066] FIG. 3 is a flow diagram of a method 300 of estimating a hydrogen content in an exhaust gas stream, according to an example embodiment. In particular, the controller 140 is structured to estimate the hydrogen content in an exhaust gas stream based on one or more inputs and using one or more of a lookup table or a statistical model (e.g., a regression model, a machine learning model such as artificial intelligence including neural networks, etc.).

[0067] At process 302, the controller 140 receives sensor data. In some embodiments, the sensor data includes data regarding a water content of the exhaust gas stream. For example, the information regarding the water content of the exhaust gas stream may be received from a water sensor positioned downstream of the engine 102 and upstream of the turbo device 122.

[0068] In some embodiments, the sensor data includes data regarding a water content of an intake gas stream and / or an ambient humidity. In some embodiments, the controller 140 receives data regarding the ambient humidity (e.g., from a remote computing system). As described above, the data regarding the ambient humidity may include a water content value, a relative humidity value, an ambient temperature value, and / or other information regarding the ambient humidity. In these embodiments, the water content of the intake gas stream is equal to or is based on the data regarding the ambient humidity. In some embodiments, the information regarding the water content in the intake gas stream includes the ambient humidity value received from at least one of a remote computing system or an ambient humidity sensor. In these embodiments, the water content is or is based on the ambient humidity value.

[0069] In some embodiments, the sensor data is detected by a real sensor 125. In other embodiments, the first parameter value is a determined value that is estimated by a virtual sensor 125. In some embodiments, when the sensor data includes an ambient humidity, at least a portion of the sensor data (e.g., the ambient humidity) may be received from a remote computing system, such as a server, a third-party computing system, a weather reporting service, etc.

[0070] At process 304, the controller 140 receives system operational data. The system operational data may include information regarding the operation of the system 100. For example, the controller 140 may receive information regarding an amount of air relative to an amount of fuel provided to the engine for combustion (e.g., the AFR). In some embodiments, the AFR is or is based on a target AFR (e.g., an AFR commanded by the controller 140). In other embodiments, the AFR is a measured AFR (e.g., an AFR measured and / or estimated by one or more sensors 125).

[0071] At process 306, the controller 140 estimates a hydrogen content in the exhaust gas stream. As described above, the controller 140 may estimate the hydrogen content in the exhaust gas stream using one or more models (e.g., a statistical model, a mathematical model, a machine learning model, etc.) and / or a look-up table that correlates water content in the exhaust gas stream to hydrogen content in the exhaust gas stream for a known AFR and ambient humidity. In an example embodiment, determining the hydrogen content in the exhaust gas stream may be based on a model that correlates the water content with the hydrogen content at the AFR. In some embodiments, the controller 140 may estimate the hydrogen content in the exhaust gas stream using the correlation shown in FIG. 4.

[0072] In another example embodiment, the controller 140 may estimate or determine the hydrogen content in the exhaust gas stream. For example, the controller 140 may determine a hydrogen input to the engine 102 based on the air to fuel ratio. The controller 140 then determines, based on at least the hydrogen input, an expected water content in the exhaust gas stream. The controller 140 the determines the hydrogen content in the exhaust gas stream basedon a difference between the expected water content and the measured water content (e.g., the water content value from process 302).

[0073] At process 308, the controller 140 adjusts the operation of the engine system 100. In some embodiments, the controller 140 may increase an AFR responsive to determining that the hydrogen content in the exhaust gas stream is greater than a first threshold. Increasing the AFR may include causing the fuel system 124 to provide less fuel to the engine 102 and / or causing the IAT valve 114 to provide more air to the engine 102. In some embodiments, increasing the AFR may further include adjusting an exhaust gas recirculation system (not shown) to provide more air to the engine 102. In some embodiments, increasing the AFR may include adjusting the operation of the turbo device 122, such as a variable geometry turbocharger, to provide more air to the engine 102. In some embodiments, the controller 140 may decrease an AFR responsive to determining that the hydrogen content in the exhaust gas stream is less than a second threshold, different than a first threshold. Decreasing the AFR may include causing the fuel system 124 to provide more fuel to the engine 102 and / or causing the IAT valve 114 to provide less air to the engine 102. In some embodiments, decreasing the AFR may further include adjusting an exhaust gas recirculation system (not shown) to provide less air to the engine 102. In some embodiments, decreasing the AFR may include adjusting the operation of the turbo device 122, such as a variable geometry turbocharger, to provide less air to the engine 102.

[0074] In some embodiments, adjusting the operation of the engine system 100 may include adjusting an ignition event by adjusting the operation of the igniter 106. For example, the controller 140 may increase an ignition energy, decrease an ignition energy, adjust an ignition timing, and / or otherwise adjust the operation of the igniter 106.

[0075] At process 310, the controller 140 provides an engine status notification. In some embodiments, the engine status notification includes an indication of the hydrogen content in the exhaust gas stream, such as a value for the hydrogen content, an indication that the hydrogen content is at or above a threshold, an indication that the hydrogen content is at or below the threshold, etc. In some embodiments, the engine status notification includes a state of health ofone or more components of the engine system 100. As described above, the controller 140 may determine a state of health of one or more components of the engine system 100 based on the hydrogen content of the exhaust gas stream. The controller 140 may selectively provide an engine status notification that includes an indication of the hydrogen content in the exhaust gas stream and / or an indication of the state of health of the one or more components of the engine system 100. In some embodiments, the controller 140 may cause the operator I / O device 130 to display the engine status notification (e.g., by providing a graphical user interface on a display, illuminating one or more status lights, etc.). In other embodiments, the controller 140 may provide the engine status notification to a user device (e g., a smartphone, a computer, etc.).

[0076] According to an example embodiment, the controller 140 is configured to perform the method 300. The controller 140 receives information regarding a first water content in an intake gas stream flowing to the engine 102 (e.g., at process 302). The controller 140 receives information regarding a second water content in an exhaust gas stream flowing from the engine 102 (e.g., at process 302). The controller 140 receives information regarding an air to fuel ratio for the engine 102 (e.g., at process 304). The controller 140 estimates, based on the first water content, the second water content, and the air to fuel ratio, a hydrogen content in the exhaust gas stream (e.g., at process 306). Furthermore, the controller 140 may perform one or more optional operations (e.g., at process 308 and / or at process 310). For example, the controller 140 may increase the air to fuel ratio responsive to determining that the hydrogen content is at or above a first threshold (e g., at process 308). In another example, the controller 140 may decrease the air to fuel ratio responsive to determining that the hydrogen content is at or below a second threshold, different than the first threshold.

[0077] According to another example embodiment, performing the method 300 includes receiving information regarding a first water content in an intake gas stream flowing to the engine 102 (e.g., at process 302). The method 300 also includes receiving information regarding a second water content in an exhaust gas stream flowing from the engine 102 (e.g., at process 302). The method 300 also includes receiving information regarding an air to fuel ratio for the engine 102 (e.g., at process 304). The method 300 also includes estimating, based on the firstwater content, the second water content, and the air to fuel ratio, a hydrogen content in the exhaust gas stream (e.g., at process 306). The method 300 may optionally include, for example, adjusting operation of the engine 102 based on comparing the hydrogen content to one or more thresholds.

[0078] According to yet another example embodiment, performing the method 300 includes receiving information regarding an ambient humidity proximate to the system 100 (e.g., at process 302). The method 300 also includes receiving sensor data including information regarding a water content in an exhaust gas stream flowing from the engine 102 of the system 100 (e.g., at process 302). The method 300 also includes receiving system operational data including information regarding an air to fuel ratio (e.g., at process 304). The method 300 also includes determining, based on the ambient humidity, the water content, and the air to fuel ratio, a hydrogen content in the exhaust gas stream (e g., at process 306).

[0079] Now referring to FIG. 4, a graph 400 depicting a relationship between water content in the exhaust gas stream (e.g., shown along the horizontal axis 402) and hydrogen content in the exhaust gas stream (e.g., shown along the vertical axis 404) is shown, according to an example embodiment. A first curve 406 depicts an estimated hydrogen content in the exhaust gas stream relative to a water content in the exhaust gas stream for a known or fixed (e.g., unchanging) ambient humidity and AFR. Although not shown, it should be understood that the graph 400 may include additional curves that correlate an estimated hydrogen content in the exhaust gas stream relative to a water content in the exhaust gas stream for different values of ambient humidity and AFR.

[0080] As utilized herein, the terms “approximately,” “about,” “substantially”, and similar terms are intended to have a broad meaning in harmony with the common and accepted usage by those of ordinary skill in the art to which the subject matter of this disclosure pertains. It should be understood by those of skill in the art who review this disclosure that these terms are intended to allow a description of certain features described and claimed without restricting the scope of these features to the precise numerical ranges provided. Accordingly, these terms should beinterpreted as indicating that insubstantial or inconsequential modifications or alterations of the subject matter described and claimed are considered to be within the scope of the disclosure as recited in the appended claims.

[0081] It should be noted that the term “exemplary” and variations thereof, as used herein to describe various embodiments, are intended to indicate that such embodiments are possible examples, representations, or illustrations of possible embodiments (and such terms are not intended to connote that such embodiments are necessarily extraordinary or superlative examples).

[0082] The term “coupled” and variations thereof, as used herein, means the joining of two members directly or indirectly to one another. Such joining may be stationary (e.g., permanent or fixed) or moveable (e.g., removable or releasable). Such joining may be achieved with the two members coupled directly to each other, with the two members coupled to each other using one or more separate intervening members, or with the two members coupled to each other using an intervening member that is integrally formed as a single unitary body with one of the two members. If “coupled” or variations thereof are modified by an additional term (e.g., directly coupled), the generic definition of “coupled” provided above is modified by the plain language meaning of the additional term (e.g., “directly coupled” means the joining of two members without any separate intervening member), resulting in a narrower definition than the generic definition of “coupled” provided above. Such coupling may be mechanical, electrical, or fluidic. For example, circuit A communicably “coupled” to circuit B may signify that the circuit A communicates directly with circuit B (i.e., no intermediary) or communicates indirectly with circuit B (e.g., through one or more intermediaries).

[0083] References herein to the positions of elements (e.g., “top,” “bottom,” “above,” “below”) are merely used to describe the orientation of various elements in the FIGURES. It should be noted that the orientation of various elements may differ according to other exemplary embodiments, and that such variations are intended to be encompassed by the present disclosure.

[0084] While various circuits with particular functionality are shown in FIG. 2, it should be understood that the controller 140 may include any number of circuits for completing the functions described herein. For example, the activities and functionalities of the hydrogen estimation circuit 210 may be combined in multiple circuits or as a single circuit. Additional circuits with additional functionality may also be included. Further, the controller 140 may further control other activity beyond the scope of the present disclosure.

[0085] As mentioned above and in one configuration, the “circuits” may be implemented in machine-readable medium for execution by various types of processors, such as the processor 204 of FIG. 2. Executable code may, for instance, comprise one or more physical or logical blocks of computer instructions, which may, for instance, be organized as an object, procedure, or function. Nevertheless, the executables need not be physically located together, but may comprise disparate instructions stored in different locations which, when joined logically together, comprise the circuit and achieve the stated purpose for the circuit. Indeed, a circuit of computer readable program code may be a single instruction, or many instructions, and may even be distributed over several different code segments, among different programs, and across several memory devices. Similarly, operational data may be identified and illustrated herein within circuits, and may be embodied in any suitable form and organized within any suitable type of data structure. The operational data may be collected as a single data set, or may be distributed over different locations including over different storage devices, and may exist, at least partially, merely as electronic signals on a system or network.

[0086] While the term “processor” is briefly defined above, the term “processor” and “processing circuit” are meant to be broadly interpreted. In this regard and as mentioned above, the “processor” may be implemented as one or more processors, application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), digital signal processors (DSPs), or other suitable electronic data processing components structured to execute instructions provided by memory. The one or more processors may take the form of a single core processor, multi-core processor (e.g., a dual core processor, triple core processor, quad core processor, etc.), microprocessor, etc. In some embodiments, the one or more processors may be external to theapparatus, for example the one or more processors may be a remote processor (e.g., a cloud based processor). Alternatively or additionally, the one or more processors may be internal and / or local to the apparatus. In this regard, a given circuit or components thereof may be disposed 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). To that end, a “circuit” as described herein may include components that are distributed across one or more locations.

[0087] Embodiments within the scope of the present disclosure include program products comprising computer or machine-readable media for carrying or having computer or machineexecutable instructions or data structures stored thereon. Such machine-readable media can be any available media that can be accessed by a computer. The computer readable medium may be a tangible computer readable storage medium storing the computer readable program code. The computer readable storage medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, holographic, micromechanical, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the computer readable medium may include but are not limited to a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), a portable compact disc read-only memory (CD-ROM), a digital versatile disc (DVD), an optical storage device, a magnetic storage device, a holographic storage medium, a micromechanical storage device, or any suitable combination of the foregoing. In the context of this document, a computer readable storage medium may be any tangible medium that can contain, and / or store computer readable program code for use by and / or in connection with an instruction execution system, apparatus, or device. Machine-executable instructions include, for example, instructions and data which cause a computer or processing machine to perform a certain function or group of functions.

[0088] The computer readable medium may also be a computer readable signal medium. A computer readable signal medium may include a propagated data signal with computer readable program code embodied therein, for example, in baseband or as part of a carrier wave. Such a propagated signal may take any of a variety of forms, including, but not limited to, electrical,electro-magnetic, magnetic, optical, or any suitable combination thereof. A computer readable signal medium may be any computer readable medium that is not a computer readable storage medium and that can communicate, propagate, or transport computer readable program code for use by or in connection with an instruction execution system, apparatus, or device. Computer readable program code embodied on a computer readable signal medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, Radio Frequency (RF), or the like, or any suitable combination of the foregoing.

[0089] In one embodiment, the computer readable medium may comprise a combination of one or more computer readable storage mediums and one or more computer readable signal mediums. For example, computer readable program code may be both propagated as an electromagnetic signal through a fiber optic cable for execution by a processor and stored on RAM storage device for execution by the processor.

[0090] Computer readable program code for carrying out operations for aspects of the present disclosure may be written in any combination of one or more other programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The computer readable program code may execute entirely on the user's computer, partly on the user's computer, as a stand-alone computer-readable package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider).

[0091] The program code may also be stored in a computer readable medium that can direct a computer, other programmable data processing apparatus, or other devices to function in a particular manner, such that the instructions stored in the computer readable medium produce anarticle of manufacture including instructions which implement the function / act specified in the schematic flowchart diagrams and / or schematic block diagrams block or blocks.

[0092] Although the figures and description may illustrate a specific order of method steps, the order of such steps may differ from what is depicted and described, unless specified differently above. Also, two or more steps may be performed concurrently or with partial concurrence, unless specified differently above. Such variation may depend, for example, on the software and hardware systems chosen and on designer choice. All such variations are within the scope of the disclosure. Likewise, software implementations of the described methods could be accomplished with standard programming techniques with rule-based logic and other logic to accomplish the various connection steps, processing steps, comparison steps, and decision steps.

[0093] It is important to note that the construction and arrangement of the apparatus and system as shown in the various exemplary embodiments is illustrative only. Additionally, any element disclosed in one embodiment may be incorporated or utilized with any other embodiment disclosed herein.

Claims

WHAT IS CLAIMED IS:

1. A system comprising: a controller comprising 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 operations comprising: receiving information regarding a first water content in an intake gas stream flowing to an engine; receiving information regarding a second water content in an exhaust gas stream flowing from the engine; receiving information regarding an air to fuel ratio for the engine; estimating, based on the first water content, the second water content, and the air to fuel ratio, a hydrogen content in the exhaust gas stream; and one of: increasing the air to fuel ratio responsive to determining that the hydrogen content is at or above a first threshold; or decreasing the air to fuel ratio responsive to determining that the hydrogen content is at or below a second threshold, different than the first threshold.

2. The system of claim 1, further comprising a fuel system; wherein the instructions, when executed by the at least one processor, cause the controller to perform further operations comprising: determining a state of health of at least one of the engine or the fuel system; and providing an engine status notification to an operator input / output device, the engine status notification comprising the state of health.

3. The system of claim 2, wherein determining the state of health of the engine includes operations comprising: comparing the hydrogen content to an engine exhaust hydrogen content threshold; anddetermining that a component of the engine has failed or has likely failed based on the hydrogen content exceeding a predetermined threshold.

4. The system of claim 2, wherein: the hydrogen content in the exhaust gas stream is a first hydrogen content value; and determining the state of health of the fuel system includes operations comprising: receiving information regarding a second hydrogen content value proximate an inlet of the engine; comparing the second hydrogen content value to an engine inlet hydrogen content threshold; and determining that a component of the fuel system has failed or has likely failed based on the second hydrogen content value exceeding a predetermined threshold.

5. The system of claim 1, wherein decreasing the air to fuel ratio includes causing a fuel system to provide more fuel to the engine.

6. The system of claim 1, wherein: the system comprises a turbocharger; and decreasing the air to fuel ratio comprises adjusting operation of the turbocharger to provide less air to the engine.

7. The system of claim 1, wherein: the system comprises an intake air valve; and decreasing the air to fuel ratio comprises adjusting operation of the intake air valve to provide less air to the engine.

8. The system of claim 1, wherein the instructions, when executed by the at least one processor, cause the controller to perform further operations comprising providing an engine status notification including at least one of a first indication of the hydrogen content in theexhaust gas stream or a second indication that the hydrogen content is at or above the first threshold.

9. The system of claim 8, wherein the engine status notification is provided on an operator input / output device via a graphical user interface.

10. A non-transitory computer readable medium storing instructions that, when executed by one or more processors of a computing system, cause the computing system to perform operations comprising: receiving information regarding a first water content in an intake gas stream flowing to an engine; receiving information regarding a second water content in an exhaust gas stream flowing from the engine; receiving information regarding an air to fuel ratio for the engine; estimating, based on the first water content, the second water content, and the air to fuel ratio, a hydrogen content in the exhaust gas stream; and adjusting operation of the engine based on comparing the hydrogen content to one or more thresholds.

11. The non-transitory computer readable medium of claim 10, wherein adjusting operation of the engine comprises one of: increasing the air to fuel ratio responsive to determining that the hydrogen content is at or above a first threshold of the one or more thresholds; or decreasing the air to fuel ratio responsive to determining that the hydrogen content is at or below a second threshold of the one or more thresholds, different than the first threshold.

12. The non-transitory computer readable medium of claim 10, wherein adjusting operation of the engine comprises adjusting operation of an igniter coupled to the engine responsive to the hydrogen content being at or above a first threshold of the one or more thresholds, and whereinadjusting operation of the igniter comprises at least one of increasing an ignition energy, decreasing the ignition energy, or adjusting an ignition timing.

13. The non-transitory computer readable medium of claim 10, wherein the information regarding the air to fuel ratio includes an oxygen content in the intake gas stream received from an oxygen sensor positioned at or proximate an intake manifold coupled to the engine, and the air to fuel ratio is based on the oxygen content in the intake gas stream.

14. The non-transitory computer readable medium of claim 10, wherein the information regarding the air to fuel ratio includes a target air to fuel ratio value, and the air to fuel ratio is based on the target air to fuel ratio value.

15. The non-transitory computer readable medium of claim 10, wherein the information regarding the first water content in the intake gas stream comprises an ambient humidity value received from at least one of a remote computing system or an ambient humidity sensor, and the first water content is based on the ambient humidity value.

16. The non-transitory computer readable medium of claim 10, wherein the information regarding the second water content in the exhaust gas stream is received from a water sensor positioned downstream of the engine and upstream of a turbo device.

17. A method comprising: receiving, by a controller, information regarding an ambient humidity proximate to a system; receiving, by the controller, sensor data comprising information regarding a water content in an exhaust gas stream flowing from an engine of the system; receiving system operational data comprising information regarding an air to fuel ratio; anddetermining, based on the ambient humidity, the water content, and the air to fuel ratio, a hydrogen content in the exhaust gas stream.

18. The method of claim 17, wherein determining the hydrogen content in the exhaust gas stream is based on a model that correlates the water content with the hydrogen content at the air to fuel ratio.

19. The method of claim 17, wherein the water content is a measured water content in the exhaust gas stream; and wherein determining the hydrogen content in the exhaust gas stream comprises: determining a hydrogen input to the engine based on the air to fuel ratio; determining, based on at least the hydrogen input, an expected water content in the exhaust gas stream; and determining the hydrogen content in the exhaust gas stream based on a difference between the expected water content and the measured water content.

20. The method of claim 17, further comprising one of: increasing the air to fuel ratio responsive to determining that the hydrogen content is at or above a first threshold; or decreasing the air to fuel ratio responsive to determining that the hydrogen content is at or below a second threshold, different than the first threshold.

Images