Method and system for controlling fuel injection

Abstract

Systems and methods are provided for controlling a fuel system associated with a propulsion system of a vehicle. The method includes receiving, by a processor, an ethanol concentration in a fuel in a fuel system. The fuel system includes at least two fuel injection systems. The method includes determining, by a processor, that a change in ethanol concentration in the fuel exceeds a fuel concentration threshold, and determining, by the processor, that the fuel having the change in ethanol concentration has reached a bifurcation defined between at least two fuel injection systems. The method includes determining, by the processor, a volume ratio between the at least two fuel injection systems, and outputting, by the processor, one or more control signals to command the at least two fuel injection systems based on the volume ratio.

Description

[0001] TECHNICAL FIELD The present invention relates generally to methods and systems for controlling fuel injection associated with an engine of a vehicle, and more particularly to methods and systems for controlling fuel injection of an internal combustion engine associated with a flex-fuel vehicle. Background Art

[0002] Certain vehicles are powered by internal combustion engines that burn fuel and air within cylinders to produce torque. Some of these vehicles are capable of burning fuels containing different concentrations of ethanol, and may generally be considered "flex-fuel" vehicles. For example, as the ethanol concentration in the fuel changes, a fuel system associated with the vehicle may contain fuels with two different ethanol concentrations due to refilling the vehicle with fuels having different ethanol concentrations. In some cases, the internal combustion engine may be controlled differently based on the ethanol concentration to ensure, for example, optimal fuel economy. When a fuel system contains different concentrations of ethanol, it may be difficult to determine which ethanol concentration is delivered to the cylinders.

[0003] Therefore, it is desirable to provide a method and system for controlling fuel injection of an internal combustion engine associated with a vehicle that improves the fuel economy of the vehicle. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background. Summary of the invention

[0004] According to various embodiments, a method for controlling a fuel system associated with a propulsion system of a vehicle is provided. The method includes receiving, by a processor, an ethanol concentration in a fuel in the fuel system. The fuel system includes at least two fuel injection systems. The method includes determining, by the processor, that a change in the ethanol concentration in the fuel exceeds a fuel concentration threshold, and determining, by the processor, that the fuel having the change in ethanol concentration has reached a bifurcation defined between the at least two fuel injection systems. The method includes determining, by the processor, a volume ratio between the at least two fuel injection systems, and outputting, by the processor, one or more control signals to command the at least two fuel injection systems based on the volume ratio.

[0005] The fuel concentration threshold is 20%, and determining that the change in ethanol concentration in the fuel exceeds the fuel concentration threshold also includes comparing the last known value of the ethanol concentration in the fuel with the ethanol concentration received from the fuel concentration sensor. Determining that the fuel has reached the bifurcation is based on a pump flow rate of the fuel pump, a location of the fuel concentration sensor, and a volume of a main fuel line associated with the vehicle. At least two fuel injection systems include an intake port fuel injection system and a spark ignition direct injection system, and determining a volume ratio between the intake port fuel injection system and the spark ignition direct injection system is based on a volume of the intake port fuel injection system from the bifurcation to the tip of at least one intake port fuel injector and a volume of the spark ignition direct injection system from the bifurcation to the tip of at least one direct fuel injector. The spark ignition direct injection system includes a high pressure fuel pump, and the volume of the spark ignition direct injection system includes the volume of the high pressure fuel pump. The method includes determining, by a processor, that fuel having a change in ethanol concentration has reached at least one cylinder associated with a propulsion system. The at least two fuel injection systems include a port fuel injection system and a spark ignition direct injection system, and the method includes outputting, by a processor, one or more control signals to command the port fuel injection system and the spark ignition direct injection system to disable control based on a volume ratio based on determining that fuel having a change in ethanol concentration has reached at least one cylinder. The at least two fuel injection systems include a port fuel injection system and a spark ignition direct injection system, and determining that fuel having a change in ethanol concentration has reached at least one cylinder is based on a pump flow rate of a fuel pump associated with the vehicle, a volume of the port fuel injection system from a fork to a tip of at least one port fuel injector, and a volume of the spark ignition direct injection system from a fork to a tip of at least one direct fuel injector.

[0006] A vehicle is also provided. The vehicle includes a propulsion system. The propulsion system includes a fuel system having a fuel tank configured to receive fuel, a fuel pump fluidly connected to the fuel tank and configured to guide the fuel to a main fuel line, and the main fuel line is fluidly connected to at least two fuel injection systems at a fork. The vehicle includes a fuel concentration sensor, which is connected to the main fuel line and configured to observe the ethanol concentration in the fuel. The vehicle includes a controller with a processor, which is configured to: determine whether the ethanol concentration in the fuel has a change greater than a fuel concentration threshold based on the ethanol concentration in the fuel; determine whether the fuel with a change in ethanol concentration has reached the fork based on the change in ethanol concentration being greater than the fuel concentration threshold; determine a volume ratio between the at least two fuel injection systems based on the fuel with a change in ethanol concentration reaching the fork; and output one or more control signals to command the at least two fuel injection systems based on the volume ratio.

[0007] The fuel concentration threshold is 20%. The controller is configured to determine that the fuel has reached the fork based on a pump flow rate of the fuel pump, a location of a fuel concentration sensor, and a volume of a main fuel line associated with the vehicle. The at least two fuel injection systems include an intake port fuel injection system and a spark ignition direct injection system, and the controller is configured to determine a volume ratio between the intake port fuel injection system and the spark ignition direct injection system based on a volume of the intake port fuel injection system from the fork to the tip of at least one intake port fuel injector and a volume of the spark ignition direct injection system from the fork to the tip of at least one direct fuel injector. The spark ignition direct injection system includes a high pressure fuel pump, and the volume of the spark ignition direct injection system includes the volume of the high pressure fuel pump. The controller is also configured to determine that fuel with a change in ethanol concentration has reached at least one cylinder associated with the propulsion system. The at least two fuel injection systems include a port fuel injection system and a spark ignition direct injection system, and based on determining that fuel with a change in ethanol concentration has reached at least one cylinder, the controller is further configured to output one or more control signals to command the port fuel injection system and the spark ignition direct injection system to disable control based on the volume ratio. The at least two fuel injection systems include a port fuel injection system and a spark ignition direct injection system, and the controller is configured to determine that fuel with a change in ethanol concentration has reached at least one cylinder based on a pump flow rate of a fuel pump, a volume of the port fuel injection system from a fork to a tip of at least one port fuel injector, and a volume of the spark ignition direct injection system from a fork to a tip of at least one direct fuel injector.

[0008] A method for controlling a fuel system associated with a propulsion system of a vehicle is also provided. The method includes receiving, by a processor, an ethanol concentration in fuel in the fuel system. The fuel system includes an intake port fuel injection system and a spark ignition direct injection system. The method includes determining, by the processor, that a change in ethanol concentration in the fuel exceeds a fuel concentration threshold, and determining, by the processor, that the fuel having the change in ethanol concentration has reached a bifurcation defined between the intake port fuel injection system and the spark ignition direct injection system. The method includes determining, by the processor, a volume ratio between the intake port fuel injection system and the spark ignition direct injection system, and outputting, by the processor, one or more control signals to command the intake port fuel injection system and the spark ignition direct injection system based on the volume ratio. The method includes determining, by the processor, that the fuel having the change in ethanol concentration has reached at least one cylinder associated with the propulsion system, and based on determining that the fuel having the change in ethanol concentration has reached at least one cylinder, outputting, by the processor, one or more control signals to command the intake port fuel injection system and the spark ignition direct injection system to disable control based on the volume ratio.

[0009] Determining that fuel has reached the bifurcation is based on a pump flow rate of a fuel pump and a volume of a main fuel line associated with the vehicle. Determining a volume ratio between a port fuel injection system and a spark ignition direct injection system is based on a volume of the port fuel injection system from the bifurcation to a tip of at least one port fuel injector and a volume of the spark ignition direct injection system from the bifurcation to a tip of at least one direct fuel injector. Determining that fuel having a variation in ethanol concentration has reached at least one cylinder is based on a pump flow rate of a fuel pump associated with the vehicle, a volume of the port fuel injection system from the bifurcation to a tip of at least one port fuel injector, and a volume of the spark ignition direct injection system from the bifurcation to a tip of at least one direct fuel injector. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Exemplary embodiments will be described below with reference to the following drawings, wherein like reference numerals represent like elements, and wherein:

[0011] Figure 1 is a functional block diagram illustrating a vehicle including a fuel injection control system according to various embodiments;

[0012] Figure 2 According to various embodiments, Figure 1 Schematic diagram of the propulsion system of a vehicle, Figure 1 The vehicle includes a fuel injection control system;

[0013] Figure 3 is a data flow diagram illustrating control modules associated with a fuel injection control system of a vehicle according to various embodiments; and

[0014] Figure 4 is a flowchart illustrating a control method performed by a fuel injection control system of a vehicle according to various embodiments. DETAILED DESCRIPTION

[0015] The following detailed description is merely exemplary in nature and is not intended to limit application and use. In addition, it is not intended to be bound by any express or implied theory presented in the preceding introduction, the invention summary, or the following detailed description. As used herein, the term module refers to any hardware, software, firmware, electronic control component, processing logic and / or processor device, alone or in any combination, including but not limited to: application-specific integrated circuits (ASICs), electronic circuits, processors (shared, dedicated or groups) and memories that execute one or more software or firmware programs, combinational logic circuits, and / or other suitable components that provide the described functions.

[0016] Embodiments of the present disclosure may be described herein in terms of functional and / or logical block components and various processing steps. It should be understood that such block components may be implemented by any number of hardware, software, and / or firmware components configured to perform a specified function. For example, embodiments of the present disclosure may employ various integrated circuit components, such as memory elements, digital signal processing elements, logic elements, lookup tables, etc., which may perform various functions under the control of one or more microprocessors or other control devices. In addition, those skilled in the art will appreciate that embodiments of the present disclosure may be practiced in conjunction with any number of systems, and the systems described herein are merely exemplary embodiments of the present disclosure.

[0017] For the sake of brevity, conventional techniques related to signal processing, data transmission, signaling, control, machine learning models, and other functional aspects of the system (and the individual operating components of the system) may not be described in detail herein. In addition, the connecting lines shown in the various figures contained herein are intended to represent exemplary functional relationships and / or physical connections between the various elements. It should be noted that there may be many alternative or additional functional relationships or physical connections in the embodiments of the present disclosure. As used herein, the term "approximately" means within 10%, and the term "substantially" means within 10%.

[0018] refer to Figure 1 According to various embodiments, a fuel injection control system, generally shown as 100, is associated with a vehicle 10. Generally, the fuel injection control system (or simply "system") 100 generates one or more control signals for controlling the volume of fuel provided to a propulsion system 20 of the vehicle 10. In various embodiments, the propulsion system 20 includes a fuel injection system 150, which is a dual fuel injection system having at least two injection systems, each of which provides fuel to the propulsion system 20 according to controlled timing and controlled amounts. As will be discussed, in one example, the fuel injection system 150 includes a port fuel injection (PFI) system 152 and a spark ignition direct injection (SIDI) system 154 associated with the propulsion system 20 of the vehicle 10. Figure 2 ). It will be appreciated that other fuel injection systems may be implemented in various embodiments, as the present disclosure is not limited to this example.

[0019] In various embodiments, the fuel injection control system 100 generates one or more control signals based on information obtained from the sensor system 28 of the vehicle 10 and / or from one or more modules associated with the vehicle 10. By controlling the volume of fuel supplied to the propulsion system 20, the fuel injection control system 100 ensures that each of the at least two fuel injection systems operates with the same or similar fuel after a fuel change occurs, such as due to refueling. Such control improves fuel economy, drivability, and can reduce emissions associated with the vehicle 10.

[0020] like Figure 1 As shown, the vehicle 10 generally includes a chassis 12, a body 14, front wheels 16, and rear wheels 18. The body 14 is disposed on the chassis 12 and substantially surrounds the components of the vehicle 10. The body 14 and the chassis 12 may together form a frame. The vehicle wheels 16-18 are each rotatably coupled to the chassis 12 near a corresponding corner of the body 14.

[0021] In various embodiments, the vehicle 10 is an autonomous vehicle or a semi-autonomous vehicle. It is understood that the fuel injection control system 100 can be implemented in other non-autonomous systems and is not limited to this embodiment. The vehicle 10 is depicted as a passenger car in the illustrated embodiment, but it should be understood that any other vehicle may be used, including motorcycles, trucks, sports utility vehicles (SUVs), recreational vehicles (RVs), marine vessels, aircraft, etc.

[0022] As shown, vehicle 10 generally includes a propulsion system 20, a transmission system 22, a steering system 24, a braking system 26, a sensor system 28, an actuator system 30, and at least one controller 34. In various embodiments, propulsion system 20 may include portions of an internal combustion engine and a fuel injection control system 100, as described with respect to FIG. Figure 2 discussed.

[0023] Drivetrain 22 is configured to transmit power from propulsion system 20 to vehicle wheels 16 and 18 according to a selectable speed ratio. According to various embodiments, drivetrain 22 may include a stepped ratio automatic transmission, a continuously variable transmission, or other suitable transmission.

[0024] Braking system 26 is configured to provide braking torque to vehicle wheels 16 and 18. In various embodiments, braking system 26 may include friction brakes, brake-by-wire brakes, regenerative braking systems such as electric motors, and / or other suitable braking systems. Steering system 24 affects the position of vehicle wheels 16 and / or 18. Although depicted as including steering wheel 25 for illustrative purposes, in some embodiments contemplated within the scope of the present disclosure, steering system 24 may not include a steering wheel.

[0025] The sensor system 28 includes one or more sensing devices 40a-40n that sense observable conditions of the external environment and / or the internal environment of the vehicle 10. In various embodiments, the sensing devices 40a-40n include, but are not limited to, a fuel concentration sensor 40a. Typically, the fuel concentration sensor 40a observes the percentage concentration of ethanol contained in the fuel flowing through the fuel injection system 150 and generates a sensor signal based on the observation. In one example, the fuel concentration sensor 40a is an ethanol sensor that observes the percentage concentration of ethanol in the fuel flowing through the fuel injection system 150. The sensor system 28 including the fuel concentration sensor 40a is connected to the controller 34 via a suitable medium (including but not limited to a bus) that enables the transmission of data, power, commands, etc.

[0026] The actuator system 30 includes one or more actuator devices 42a-42n that control one or more vehicle features, such as, but not limited to, the propulsion system 20, the transmission system 22, the steering system 24, and the braking system 26. In various embodiments, the vehicle 10 may also include Figure 1 , such as various doors, trunks, and cabin features such as air, music, lighting, touch screen display components (such as those used in conjunction with a navigation system), active safety seats or haptic seats, etc. The actuator system 30, including one or more actuator devices 42a-42n, communicates with the controller 34 via a suitable medium (including but not limited to a bus) that enables the transmission of data, power, commands, etc.

[0027] The controller 34 includes at least one processor 44 and a computer readable storage device or medium 46. The processor 44 can be any custom or commercially available processor, a central processing unit (CPU), a graphics processing unit (GPU), an application specific integrated circuit (ASIC) (e.g., a custom ASIC that implements a neural network), a field programmable gate array (FPGA), a secondary processor in a number of processors associated with the controller 34, a semiconductor-based microprocessor (in the form of a microchip or chipset), any combination thereof, or any device generally used to execute instructions. For example, the computer readable storage device or medium 46 can include volatile and non-volatile storage in read-only memory (ROM), random access memory (RAM), and keep-alive memory (KAM). KAM is a persistent or non-volatile memory that can be used to store various operating variables when the processor 44 loses power. The computer readable storage device or medium 46 may be implemented using any of a number of known memory devices, such as a PROM (programmable read only memory), an EPROM (electrical PROM), an EEPROM (electrically erasable PROM), flash memory, or any other electrical, magnetic, optical, or combination memory device capable of storing data, some of which represents executable instructions used by the controller 34 to control the vehicle 10. In various embodiments, the controller 34 is configured to implement instructions for the fuel injection control system 100. In various embodiments, when executed by the processor 44, the instructions receive and process sensor data from the sensor system 28 of the vehicle 10 and data received from other modules associated with the vehicle 10 to determine a change in the ethanol concentration in the fuel of the vehicle 10, and in response, determine whether and how to proportionally control the fuel injection system 150 based on the change in the ethanol concentration. In other words, based on the determination of the change in the percentage of ethanol in the fuel, the instructions generate control signals to control the PFI system 152 ( Figure 2 ) and SIDI system 154( Figure 2 ), so that the current fuel is discharged from the fuel injection system 150 through the operation of the propulsion system 20, so that the fuels with different ethanol concentrations reach the PFI system 152 and the SIDI system 154 substantially at the same time to ensure driving performance while improving the fuel economy and emissions associated with the vehicle 10. In general, the chemical formula of ethanol is CH3CH2OH, and it is also called alcohol, grain alcohol, and EtOH.

[0028] refer to Figure 2, an exemplary propulsion system 20 is shown in more detail. In this example, the propulsion system 20 is an internal combustion engine 112 having an engine block 114, which defines at least one cylinder 116, and the cylinder 116 has a piston 118 coupled to rotate a crankshaft. The cylinder head cooperates with the piston 118 to define a combustion chamber 124. A mixture of fuel and air is injected into the combustion chamber 124 and ignited, resulting in thermal expansion of exhaust gas, thereby causing reciprocating motion of the piston 118. The fuel may include gasoline, ethanol, a mixture of gasoline and ethanol, etc., and the internal combustion engine 112 may include at least one spark plug, etc. In this example, the internal combustion engine 112 includes eight cylinders 116, however, it should be understood that the internal combustion engine 112 may include any number of cylinders 116. The fuel injection system 150 includes a PFI system 152 and a SIDI system 154, a fuel source 160, a main fuel line 162, and a fork 164. The PFI system 152 includes a first PFI fuel rail 166 and a second PFI fuel rail 168, each of which is associated with a respective group of cylinders 116. Each of the first PFI fuel rail 166 and the second PFI fuel rail 168 is in fluid communication with the main fuel line 162 to receive fuel via a PFI fuel line 169. The PFI fuel line 169 is fluidly coupled to the main fuel line 162 at a fork 164. Each of the first PFI fuel rail 166 and the second PFI fuel rail 168 includes a plurality of port fuel injectors 170. Based on one or more control signals from the controller 34, the port fuel injectors 170 are controlled to inject fuel into the intake port 126 associated with a respective one of the cylinders 116. Each port fuel injector 170 includes any suitable port fuel injector, and each port fuel injector 170 defines an internal volume extending to a tip 170a of each port fuel injector 170.

[0029] The SIDI system 154 includes a first SIDI fuel rail 172, a second SIDI fuel rail 174, and a high-pressure fuel pump 176. The first SIDI fuel rail 172 and the second SIDI fuel rail 174 are each associated with a corresponding group of cylinders 116. Each of the first SIDI fuel rail 172 and the second SIDI fuel rail 174 includes a plurality of direct fuel injectors 178. Based on one or more control signals from the controller 34, the direct fuel injectors 178 are controlled to inject fuel directly into the corresponding cylinders 116. Each direct fuel injector 178 includes any suitable direct fuel injector, and each direct fuel injector 178 defines an internal volume extending to a tip 178a of each direct fuel injector 178. The high-pressure fuel pump 176 is in fluid communication with one or both of the first SIDI fuel rail 172 and the second SIDI fuel rail 174. In one example, the first SIDI fuel rail 172 and the second SIDI fuel rail 174 are interconnected by a fuel conduit 180, and the high-pressure fuel pump 176 is fluidly coupled to the first SIDI fuel rail 172. High pressure fuel pump 176 increases the pressure of fuel received from main fuel line 162 for injection into cylinders via direct fuel injectors 178. In this example, high pressure fuel pump 176 is in fluid communication with main fuel line 162 via SIDI fuel line 182. SIDI fuel line 182 is fluidly coupled to main fuel line 162 at bifurcation 164.

[0030] The fuel source 160 provides fuel to the fuel injection system 150. In one example, the fuel source 160 includes at least one fuel tank 186 and a fuel pump 188. The fuel tank 186 is configured to receive and hold fuel, for example, the fuel may be provided from an external source via an inlet pipe. The fuel pump 188 may be disposed within the fuel tank 186 and fluidly coupled to the fuel tank 186 and the main fuel line 162 to supply fuel from the fuel tank 186 at a predetermined or predefined flow rate. The main fuel line 162 is fluidly coupled to the fuel source 160 and guides the fuel from the fuel source 160 to the fork 164. In one example, the fuel concentration sensor 40a is fluidly coupled to the fuel injection system 150 via the main fuel line 162 and is fluidly coupled to the main fuel line 162 near or at the outlet of the fuel tank 186 to observe the fuel as it flows from the fuel tank 186 into the main fuel line 162. The fork 164 is a downstream location of the fuel source 160 where the fuel from the fuel source 160 is transferred or directed to both the PFI system 152 and the SIDI system 154. The fork 164 may include a Y-shaped pipe connector, a T-shaped pipe connector, etc. Typically, the main fuel line 162 is coupled to the fork 164 without a valve so that the fuel from the main fuel line 162 is equally supplied to the PFI fuel line 169 and the SIDI fuel line 182. It should be noted that the arrangement of the fuel source 160, the main fuel line 162, the fork 164, the PFI fuel line 169, and the SIDI fuel line 182 is merely exemplary, as the arrangement of these components may vary from vehicle to vehicle.

[0031] Typically, each cylinder 116 has at least two valves, an intake valve and an exhaust valve, each valve being actuated by a camshaft that rotates synchronously with the crankshaft. The intake valve selectively allows air to enter the combustion chamber 124 from the intake port 126, and the exhaust valve alternately allows exhaust gas to be discharged through one or more exhaust ports. In some examples, the cam phaser can selectively change the timing between the camshaft and the crankshaft. Air can be distributed to one or more air intake ports through the intake manifold. The intake duct can provide air from the ambient environment to the intake manifold, and a throttle body can be provided to regulate the air flow into the intake manifold. At least the fuel pump 188, the intake port fuel injector 170, the direct fuel injector 178, the high pressure fuel pump 176, and the throttle body can be communicated with the controller 34 through a suitable medium (including but not limited to a bus) that enables the transmission of data, power, commands, etc.

[0032] As about Figure 3 More details are shown and reference is made to Figure 1 and Figure 2, the data flow diagram illustrates an embodiment of a control module 200 of the fuel injection control system 100, which may be implemented by or incorporated into the controller 34 and / or the processor 44. In various embodiments, the control module 200 may be implemented as one or more sub-modules. Various embodiments of the control module 200 according to the present disclosure may include any number of sub-modules embedded within the controller 34. As may be appreciated, Figure 3 The submodules shown may be combined and / or further divided to generate control signals to the fuel injection system 150. The data input to the control module 200 may be from the sensor system 28 ( Figure 1 and Figure 2 ), received from other control modules (not shown) associated with the vehicle 10, and / or determined / modeled by other submodules (not shown) within the controller 34. In various embodiments, the control module 200 includes a fuel data repository 202, a fuel concentration monitoring module 204, a fuel system data repository 206, a fuel system monitoring module 208, a timer module 209, and a fuel injector control module 210.

[0033] The fuel data repository 202 stores data for a fuel concentration threshold 212 and a last known value 214. The fuel concentration threshold 212 is a predefined or predetermined value of the percentage change in the concentration of ethanol in the fuel. In one example, the fuel concentration threshold 212 is approximately 20%. The last known value 214 is the value of the percentage concentration of ethanol in the fuel that was last observed by the fuel concentration sensor 40a and stored in the fuel data repository 202 by the fuel concentration monitoring module 204.

[0034] The fuel concentration monitoring module 204 receives concentration data 216 as input. The concentration data 216 is data received from the fuel concentration sensor 40a and / or data modeled by other means, which includes the observed percentage of ethanol in the fuel. Based on the reception of the concentration data 216, the fuel concentration monitoring module 204 queries the fuel data repository 202 and retrieves the last known value 214 of the percentage concentration of ethanol in the fuel. The fuel concentration monitoring module 204 compares the last known value 214 of the ethanol concentration with the concentration data 216 and determines the percentage change of the ethanol concentration. The fuel concentration monitoring module 204 queries the fuel data repository 202 and retrieves the fuel concentration threshold 212. The fuel concentration monitoring module 204 determines whether the percentage change of the ethanol concentration is greater than the fuel concentration threshold 212, or whether the percentage change of the ethanol concentration is greater than about 20%. If the percentage change of the ethanol concentration is greater than about 20%, the fuel concentration monitoring module 204 sets the fuel change data 218 for the fuel system monitoring module 208. The fuel change data 218 is data indicating that the ethanol concentration in the fuel has changed by at least the value of the fuel concentration threshold 212, such that the fuel injection system 150 should be purged to enable the fuel change to reach each of the port fuel injectors 170 and the direct fuel injectors 178 substantially simultaneously. The fuel concentration monitoring module 204 stores the ethanol concentration from the observed concentration data 216 of the fuel concentration sensor 40a as the last known value 214 in the fuel data repository 202.

[0035] The fuel system data repository 206 stores data for a bifurcation time value 220, PFI volume data 222, SIDI volume data 224, and cylinder time value 226. The bifurcation time value 220 is a predefined or predetermined value for the amount of time in seconds it takes for fuel to flow from the fuel concentration sensor 40a through the main fuel line 162 to the bifurcation 164. Generally, since the flow rate of the fuel is a known or predefined pump flow rate of the fuel pump 188, such as in liters per second (L / s), and the volume of the main fuel line 162 is also a known or predefined value, such as in liters (L), the bifurcation time value 220 can be determined based on the pump flow rate of the fuel pump 188 and the volume of the main fuel line 162 from the fuel concentration sensor 40a to the bifurcation 164. In one example, the pump flow rate is about 200 liters per hour (Lph) to about 400 liters per hour (Lph), the volume of the main fuel line 162 is about 1 liter (L) to about 3 liters (L), and the bifurcation time value 220 is about 2 seconds (s) to about 5 seconds (s). It should be noted that the pump flow rate, the volume of the main fuel line 162, and the bifurcation time value 220 may vary depending on the arrangement of the fuel injection system 150 within the vehicle 10. The PFI volume data 222 is a predefined or predetermined value of the volume of the PFI system 152. Generally, the PFI volume data 222 is the sum of the volume of the PFI fuel line 169 (from the bifurcation 164 to the first PFI fuel rail 166), the volume of the first PFI fuel rail 166, the volume of the second PFI fuel rail 168, and the volume of each intake port fuel injector 170 to the tip 170a of each intake port fuel injector 170. In one example, the PFI volume data 222 is approximately 0.1 liters (L). It should be noted that although the fuel system data repository 206 is described herein as storing predefined values ​​of the bifurcation time value 220, the PFI volume data 222, the SIDI volume data 224, and the cylinder timing value 226, in other embodiments, a control module for the fuel injection control system 100 may include a fuel system module that determines each of the bifurcation time value 220, the PFI volume data 222, the SIDI volume data 224, and the cylinder timing value 226 in real time during operation of the vehicle 10.

[0036] The SIDI volume data 224 is a predefined or predetermined value of the volume of the SIDI volume data 224. Typically, the SIDI volume data 224 is the sum of the volume of the SIDI fuel line 182 (from the fork 164 to the first SIDI fuel rail 172), the volume of the high pressure fuel pump 176, the volume of the first SIDI fuel rail 172, the volume of the second SIDI fuel rail 174, and the volume of each direct fuel injector 178 to the tip 178a of each direct fuel injector 178. In one example, the SIDI volume data 224 is approximately 0.3 liters (L). The cylinder time value 226 is a predefined or predetermined value of the amount of time in seconds it takes for fuel to flow from the fork 164 through each of the PFI system 152 and the SIDI system 154 to the cylinder 116, respectively. In general, since the flow rate of the fuel is a known or predefined pump flow rate of the fuel pump 188, such as in liters per second (L / s), and the volume of each of the PFI system 152 and the SIDI system 154 is also a known or predefined value, such as in liters (L), the cylinder time value 226 can be determined based on the pump flow rate of the fuel pump 188 and the volume of the PFI system 152 and the SIDI system 154. In one example, the cylinder time value 226 is about 0.5 seconds (s) to about 2.5 seconds (s). It should be noted that the volume of each of the PFI system 152 and the SIDI system 154 and the cylinder time value 226 may vary depending on the arrangement of the fuel injection system 150 within the vehicle 10.

[0037] The fuel system monitoring module 208 receives the fuel change data 218 as input. Based on the receipt of the fuel change data 218, the fuel system monitoring module 208 sets the enablement data 228 for the timer module 209. The fuel system monitoring module 208 queries the fuel system data repository 206 and retrieves the bifurcation time value 220. The fuel system monitoring module 208 receives the time data 230 from the timer module 209 as input. The time data 230 is the time value of the timer that is set based on the receipt of the enablement data 228. In other words, the time data 230 is the amount of time that has elapsed since it was determined that the change in ethanol concentration exceeded the fuel concentration threshold 212. The fuel system monitoring module 208 determines whether the time value of the time data 230 is equal to the bifurcation time value 220, so that the fuel with the change in ethanol concentration has reached the bifurcation portion 164. Based on the time of the timer being equal to the bifurcation time value 220, the fuel system monitoring module 208 sets the bifurcation data 232 for the fuel injector control module 210. The branching data 232 is data indicating that the fuel from the fuel concentration sensor 40 a has reached the branching portion 164 .

[0038] The timer module 209 receives as input the enable data 228 from the fuel system monitoring module 208. Based on the enable data 228, the timer module 209 sets the timer equal to zero and starts the timer. The timer module 209 sets the time data 230 for the fuel system monitoring module 208 and the fuel injector control module 210, which includes the time value of the timer. It should be noted that the timer module 209 is merely exemplary, as the timer module 209 may include, for example, a clock associated with the controller 34.

[0039] The fuel injector control module 210 receives the bifurcated data 232 as input. Based on receipt of the bifurcated data 232, the fuel injector control module 210 queries the fuel system data repository 206 and retrieves the PFI volume data 222 and the SIDI volume data 224. The fuel injector control module 210 determines a volume ratio of the SIDI system 154 to the PFI system 152 based on the SIDI volume data 224 and the PFI volume data 222. The fuel injector control module 210 outputs ratio control data 234 to the fuel injection system 150 to control the port fuel injectors 170 and the direct fuel injectors 178. The ratio control data 234 is one or more control signals for commanding the port fuel injectors 170 and the direct fuel injectors 178 to operate based on the determined volume ratio between the SIDI system 154 and the PFI system 152 so that fuel is uniformly discharged from the fuel injection system 150 by combustion of the internal combustion engine 112 during a normal combustion process. This ensures that the fuel in the SIDI system 154 and the PFI system 152 are purged at the same time, so that fuels with different ethanol concentrations arrive at the tip 170a of the port fuel injector 170 and the tip 178a of the direct fuel injector 178 at the same time. In this example, the SIDI volume data 224 is 0.3 liters (L) and the PFI volume data 222 is 0.1 liters (L). The determined volume ratio is 3 (SIDI) to 1 (PFI), and the ratio control data 234 is one or more control signals sent to the fuel injection system 150 to operate the direct fuel injector 178 at 75% and the port fuel injector 170 at 25%. Generally, one or more control signals to operate the direct fuel injector 178 at 100% will command the fuel injection system 150 to operate the direct fuel injector 178 and not operate the port fuel injector 170. Similarly, one or more control signals to operate direct fuel injector 178 at 0% will command fuel injection system 150 to operate port fuel injector 170 without operating direct fuel injector 178 .

[0040] The fuel injector control module 210 queries the fuel system data repository 206 and retrieves the cylinder timing value 226. The fuel injector control module 210 receives as input the timing data 230 from the timer module 209. The fuel injector control module 210 compares the cylinder timing value 226 to the timing data 230 and determines whether the timing data 230 is equal to the cylinder timing value 226. Based on the timing data 230 being equal to the cylinder timing value 226, the fuel injector control module 210 outputs normal control data 236. The normal control data 236 is one or more control signals that command the port fuel injectors 170 and the direct fuel injectors 178 to resume normal operation or to disable proportional control.

[0041] Reference now Figure 4 , and continue to refer to Figure 1-Figure 3 , the flow chart shows that according to the present disclosure, Figure 1 The method 300 is executed by the fuel injection control system 100 of the embodiment of the present invention. In one example, the method 300 is executed by the processor 44 of the controller 34. As can be understood from the present disclosure, the order of operations within the method 300 is not limited to the following. Figure 4 The method 300 is not performed in the order shown, but may be performed in one or more different orders where applicable and in accordance with the present disclosure. In various embodiments, the method 300 may be scheduled to run based on one or more predetermined events, and / or may run continuously during operation of the vehicle 10.

[0042] The method starts at 302. At 304, the method 300 receives the percentage concentration of ethanol in the fuel from the fuel concentration sensor 40a and / or a module that models the value. At 306, the method 300 queries the fuel data repository 202 and retrieves the last known value 214 of the percentage concentration of ethanol. At 308, the method 300 compares the percentage concentration of ethanol observed by the fuel concentration sensor 40a with the last known value 214 to determine a change in the percentage concentration of ethanol. The method 300 queries the fuel data repository 202 and retrieves the fuel concentration threshold 212. The method 300 determines whether the change in the percentage concentration of ethanol is greater than the fuel concentration threshold 212. If true, the method 300 proceeds to 310. Otherwise, the method 300 ends at 312.

[0043] At 310, the method 300 sets the timer equal to zero. At 314, the method 300 determines the bifurcation time value 220. The method 300 compares the time value of the timer to the bifurcation time value 220 and determines whether the time value is equal to the bifurcation time value 220, such that fuels with different ethanol percentages have reached the bifurcation 164. If the fuel has reached the bifurcation 164, the method 300 proceeds to 316. Otherwise, the method 300 loops until the time value of the timer is equal to the bifurcation time value 220.

[0044] At 316, method 300 determines a volume ratio of SIDI system 154 to PFI system 152 based on SIDI volume data 224 and PFI volume data 222. At 318, method 300 outputs one or more control signals to command port fuel injector 170 and direct fuel injector 178 to operate based on the determined volume ratio between SIDI system 154 and PFI system 152 so that fuel is uniformly discharged from fuel injection system 150. At 320, method 300 determines whether fuel with a change in ethanol concentration has reached cylinder 116. In one example, method 300 retrieves cylinder time value 226 and compares the time value of the timer to cylinder time value 226. If the time value of the timer is equal to cylinder time value 226, method 300 determines that fuel with a change in ethanol concentration has reached cylinder 116 and proceeds to 320. Otherwise, method 300 loops.

[0045] At 322, method 300 outputs one or more control signals to command port fuel injector 170 and direct fuel injector 178 to resume normal operation or to disable ratio control. At 324, method 300 sets the percentage concentration of ethanol observed by fuel concentration sensor 40a to the last known value 214 of the percentage concentration of ethanol in the fuel. Method 300 ends at 312.

[0046] Thus, the fuel injection control system 100 enables the vehicle 10 to operate more efficiently when the ethanol concentration in the fuel changes, for example, which may occur during refueling of the vehicle 10. Generally, by controlling the intake port fuel injectors 170 and the direct fuel injectors 178 of the fuel injection system 150 in proportion or based on the determined volume ratio, the fuel in the fuel injection system 150 (before adding the fuel with the change in ethanol concentration) is substantially uniformly discharged from the fuel injection system 150, so that the new fuel (the fuel with the change in ethanol concentration) is received at the tips 170a, 178a of each intake port fuel injector 170 and the direct fuel injector 178, respectively, at substantially the same time. This enables the controller 34 to control the fuel injection system 150 based on the same fuel, which improves fuel economy and emissions while ensuring drivability. The fuel injection control system 100 also reduces the complexity of the instructions associated with the control of the fuel injection system 150.

[0047] Although at least one exemplary embodiment has been presented in the foregoing detailed description, it should be understood that there are a large number of variations. It should also be understood that the exemplary embodiment or multiple exemplary embodiments are only examples and are not intended to limit the scope, applicability or configuration of the present disclosure in any way. On the contrary, the foregoing detailed description will provide a convenient roadmap for implementing the exemplary embodiment or multiple exemplary embodiments for those skilled in the art. It should be understood that various changes may be made to the functions and arrangements of the elements without departing from the scope of the present disclosure as set forth in the attached claims and their legal equivalents.

Claims

1. A method for controlling a fuel system associated with a propulsion system of a vehicle, the method comprising: receiving, by a processor, an ethanol concentration in a fuel in the fuel system, the fuel system comprising at least two fuel injection systems; determining, by the processor, that a change in the ethanol concentration in the fuel exceeds a fuel concentration threshold; determining, by the processor, that the fuel having the change in ethanol concentration has reached a bifurcation defined between the at least two fuel injection systems; determining, by the processor, a volume ratio between the at least two fuel injection systems; as well as One or more control signals are output by the processor to command the at least two fuel injection systems based on the volume ratio.

2. The method of claim 1 , wherein the fuel concentration threshold is 20%, determining that the change in the ethanol concentration in the fuel exceeds the fuel concentration threshold further comprises comparing a last known value of the ethanol concentration in the fuel with the ethanol concentration received from a fuel concentration sensor, and determining that the fuel has reached the bifurcation is based on a pump flow rate of a fuel pump, a location of the fuel concentration sensor, and a volume of a main fuel line associated with the vehicle.

3. The method according to claim 1, wherein the at least two fuel injection systems include an intake manifold fuel injection system and a spark ignition direct injection system, determining the volume ratio between the intake manifold fuel injection system and the spark ignition direct injection system is based on the volume of the intake manifold fuel injection system from the fork portion to the tip of at least one intake manifold fuel injector and the volume of the spark ignition direct injection system from the fork portion to the tip of at least one direct fuel injector, the spark ignition direct injection system includes a high-pressure fuel pump, and the volume of the spark ignition direct injection system includes the volume of the high-pressure fuel pump.

4. The method according to claim 1, further comprising: A determination is made, by the processor, that the fuel having the change in ethanol concentration has reached at least one cylinder associated with the propulsion system.

5. The method of claim 4, wherein the at least two fuel injection systems include a port fuel injection system and a spark ignition direct injection system, and the method further comprises: Based on determining that the fuel having the change in the ethanol concentration has reached the at least one cylinder, one or more control signals are output by the processor to command disabling control of the port fuel injection system and the spark-ignition direct injection system based on the volume ratio.

6. The method of claim 4 wherein the at least two fuel injection systems include a port fuel injection system and a spark ignition direct injection system, and determining that the fuel having the change in ethanol concentration has reached the at least one cylinder is based on a pump flow rate of a fuel pump associated with the vehicle, a volume of the port fuel injection system from the bifurcation to a tip of at least one port fuel injector, and a volume of the spark ignition direct injection system from the bifurcation to a tip of at least one direct fuel injector.

7. A means of transport, comprising: a propulsion system including a fuel system having a fuel tank configured to receive fuel, a fuel pump fluidly coupled to the fuel tank and configured to direct the fuel to a main fuel line, the main fuel line fluidly coupled to at least two fuel injection systems at a bifurcation; a fuel concentration sensor coupled to the main fuel line and configured to observe an ethanol concentration in the fuel; A controller having a processor configured to: determining, based on the ethanol concentration in the fuel, whether the ethanol concentration in the fuel has a change that is greater than a fuel concentration threshold; determining whether the fuel having the change in ethanol concentration has reached the bifurcated portion based on the change in ethanol concentration being greater than the fuel concentration threshold; determining a volume ratio between the at least two fuel injection systems based on the fuel having the change in ethanol concentration arriving at the bifurcated portion; as well as One or more control signals are output to command the at least two fuel injection systems based on the volume ratio.

8. The vehicle of claim 7, wherein the fuel concentration threshold is 20%, and the controller is configured to determine that the fuel has reached the bifurcation based on a pump flow rate of the fuel pump, a location of the fuel concentration sensor, and a volume of the main fuel line associated with the vehicle.

9. A vehicle according to claim 7, wherein the at least two fuel injection systems include an intake manifold fuel injection system and a spark ignition direct injection system, and the controller is configured to determine a volume ratio between the intake manifold fuel injection system and the spark ignition direct injection system based on the volume of the intake manifold fuel injection system from the fork portion to the tip of at least one intake manifold fuel injector and the volume of the spark ignition direct injection system from the fork portion to the tip of at least one direct fuel injector, the spark ignition direct injection system includes a high-pressure fuel pump, and the volume of the spark ignition direct injection system includes the volume of the high-pressure fuel pump.

10. A vehicle according to claim 7, wherein the at least two fuel injection systems include an intake manifold fuel injection system and a spark ignition direct injection system, and the controller is configured to determine that the fuel with the change in ethanol concentration has reached at least one cylinder based on a pump flow rate of the fuel pump, a volume of the intake manifold fuel injection system from the fork portion to the tip of at least one intake manifold fuel injector, and a volume of the spark ignition direct injection system from the fork portion to the tip of at least one direct fuel injector, and based on determining that the fuel with the change in ethanol concentration has reached the at least one cylinder, the controller is also configured to output one or more control signals to command the intake manifold fuel injection system and the spark ignition direct injection system to disable control based on the volume ratio.

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