CN105358817B - For calculating the System and method for of fuel injector working time using fuel system pressure prediction - Google Patents

Abstract

The disclosure provides the System and method for for the running time for calculating fuel injector.The system can include one or more module being located in control system.The control system provides the pressure distribution in the fuel system of fuel under high pressure using fuel injector described in the information modeling and pre- direction finding that can be obtained before fuel injection signal is transferred to the fuel injector, and calculates the running time of the fuel injector using the information together with addition fuel command.

Description

System for calculating fuel injector operating hours using fuel system pressure prediction with method

Cross-references to related applications

This application requires the title of "SYSTEM AND METHOD FOR FUEL INJECTORON-TIME CALCULATION USING FUEL SYSTEM PRESSURE PREDICTION (used to use fuel system pressure prediction to calculate fuel injector working time system and method)" submitted in July 2013, U.S. provisional patent The priority of application Serial No. 61/864,384, the entire disclosure of which application is expressly incorporated herein by reference.

technical field

The present disclosure relates to fuel injectors for internal combustion engines and systems and methods for calculating actual injection times (referred to as operating times) using fuel system pressure predictions.

Background technique

The amount of fuel injected into the combustion chamber by the fuel injector is a function of the fuel system supply or rail pressure, the cylinder pressure or combustion chamber pressure, and the interval the fuel injector remains open (referred to as the on-time). The conventional approach to determining fuel injector on time given a desired fuel quantity and fuel system pressure is to use fuel system, fuel rail or common rail pressure and desired fuel quantity as independent variables or parameters and fuel as dependent variable. A predetermined two-dimensional lookup table of injector operating times.

A challenge with conventional approaches is that the pressure distribution in the fuel system can vary relative to a look-up table calibration or reference, thereby changing the actual volume, actual total amount or amount of fuel delivered. Factors that may change the pressure profile include pressure waves in the fuel system, fuel rail or common rail, engine speed, start of injection (SOI) designed as a function of input rather than fuel system pressure and desired fuel quantity, and fuel system pressure settings. Fixed value changes.

Contents of the invention

In one embodiment of the present disclosure, a fuel assembly for an engine includes a fuel reservoir and at least one fuel injector fluidly coupled with the fuel reservoir. The fuel injector is configured to move between an open position allowing fuel flow from the fuel injector and a closed position prohibiting fuel flow from the injector. The fuel assembly further includes a control system including a controller operatively coupled to the fuel injector. The controller is configured to receive at least one parameter of the fuel assembly. During operation of the engine, the controller is configured to adjust an amount of time the fuel injector remains in the open position in response to the parameter.

According to another embodiment of the present disclosure, a fuel assembly for an engine includes: at least one fuel injector; and a control system for the fuel assembly. The control system includes: a controller configured to receive at least one parameter of the fuel assembly; means for determining when fuel is flowing from the fuel injector; means for pressure distribution of the fuel assembly; and means for adjusting the timing of fuel flow from the fuel injector during operation of the engine in response to the fuel distribution predicted for the fuel assembly.

In another exemplary embodiment of the present disclosure, a method of operating a fuel assembly of an engine includes: providing at least one fuel injector that receives a parameter of the fuel assembly during operation of the engine; And during operation of the engine, predicting a pressure profile of the fuel assembly based on the parameter of the fuel assembly. The method also includes: calculating an amount of time during operation of the engine that fuel flows from the fuel injector; and delivering to the fuel injector during operation of the engine a The signal for the amount of time the fuel injector is flowing.

The advantages and features of the embodiments of the present disclosure will be more apparent when viewing the detailed description according to the following exemplary embodiments in conjunction with the accompanying drawings.

Description of drawings

FIG. 1 is a schematic diagram of an internal combustion engine incorporating a first exemplary embodiment of the present disclosure.

FIG. 2 is a schematic illustration of a portion of the engine of FIG. 1 .

detailed description

Referring to FIG. 1 , a portion of an internal combustion engine according to a first exemplary embodiment of the present disclosure is shown as a simplified schematic diagram and generally indicated at 10 . The engine 10 includes a control system that generates a fuel injection signal that is communicated to an electric drive where the fuel injection signal is amplified. The fuel injection signal is then delivered to the fuel injector, which opens the nozzle or needle valve element to allow fuel to flow through the fuel injector into the combustion chamber. To calculate the actual operating time of the fuel injector, the control system models and predicts the pressure distribution in the fuel system providing high pressure fuel to the fuel injector using information available before the fuel injection signal is delivered to the fuel injector. The control system uses the pressure model and the fueling command to calculate the fuel injector operating time. Information useful for modeling pressure in the fuel system may include pumping commands, fuel system setpoint or target fuel system pressure, pressure measurement signals from the fuel system, dimensions of the common fuel rail or reservoir, and fuel properties.

The engine 10 includes an engine block 12 including an engine block 14 and a cylinder head 16 attached to the engine block 14 ; a fuel system 18 and a control system 20 . Control system 20 receives signals from sensors located on engine 10 and communicates control signals to devices located on engine 10 to control the function of these devices. The engine block 12 includes a crankshaft 22 , a plurality of pistons 24 and a plurality of connecting rods 26 . Pistons 24 are positioned to reciprocate within a plurality of engine cylinders 28 , one piston 24 positioned within one engine cylinder 28 . A connecting rod 26 connects a piston 24 to the crankshaft 22 . As will be seen, movement of piston 24 under the action of the combustion process in engine 10 causes connecting rod 26 to move crankshaft 22 .

A plurality of fuel injectors 30 are located within the cylinder head 16 . Each fuel injector 30 is fluidly connected to a combustion chamber 32 each formed by a piston 24 , the cylinder head 16 , and the portion of the engine cylinder 28 extending between the respective piston 24 and the cylinder head 16 .

Fuel system 18 provides fuel to injector 30 , which is then injected into combustion chamber 32 via action of fuel injector 30 , resulting in one or more injection events. Fuel system 18 includes a fuel circuit 34 , a fuel tank 36 containing fuel, a high pressure fuel pump 38 positioned along fuel circuit 34 downstream of fuel tank 36 , and a fuel reservoir or rail 40 positioned along fuel circuit 34 downstream of high pressure fuel pump 38 . Although fuel reservoir or rail 40 is shown as a single unit or element, reservoir 40 may be distributed over multiple elements that deliver or receive high pressure fuel, such as fuel injectors 30, high pressure fuel pump 38, and connections of high pressure fuel to multiple Any lines, channels, pipes, hoses, etc. of a component. Injector 30 receives fuel from fuel reservoir 40 . Fuel system 18 may also include an inlet metering valve 44 positioned along fuel circuit 34 upstream of high pressure fuel pump 38 and one or more outlet check valves 46 positioned along fuel circuit 34 downstream of high pressure fuel pump 38 to allow One-way fuel flow from fuel pump 38 to fuel reservoir 40 . Although not shown, other components may be positioned along fuel circuit 34 . For example, an inlet check valve may be positioned downstream of inlet metering valve 44 and upstream of high pressure fuel pump 38 , or may be incorporated into high pressure fuel pump 38 . Inlet metering valve 44 has the ability to alter or shut off fuel flow to high pressure fuel pump 38 and fuel flow to fuel reservoir 40 is thus shut off. Fuel circuit 34 connects fuel reservoir 40 to fuel injector 30 , thereby providing a controlled amount of fuel to combustion chamber 32 . Fuel system 18 may also include a low pressure fuel pump 48 positioned along fuel circuit 34 between fuel tank 36 and high pressure fuel pump 38 . Low pressure fuel pump 48 increases fuel pressure to a first pressure level before fuel flows into high pressure fuel pump 38 .

Control system 20 may include a controller or control module 50 and a wiring harness 52 . Some aspects of the disclosure are described in terms of sequences of actions to be performed by elements of a computer system or other hardware capable of executing programmed instructions (eg, a general purpose computer, special purpose computer, workstation, or other programmable data processing device). It is to be appreciated that in each of the embodiments, special purpose circuitry (e.g., discrete logic gates interconnected to perform specialized functions), one or more processors (e.g., one or more microprocessors, central processing units ( CPU) and or an application specific integrated circuit) or a combination of both to perform various actions. For example, the implementations may be implemented in hardware, software, firmware, middleware, microcode, or any combination of these. The commands may be program code or code segments to perform the necessary tasks and may be stored in a machine-readable medium such as a storage medium or other memory. A code segment may represent a process, function, subroutine, program, routine, subroutine, module, software package, class, or any combination of commands, data structures, or program statements. A code segment can be coupled to another code segment or a hardware circuit by passing and/or receiving information, data, arguments, parameters, or stored contents.

In addition, non-transitory machine-readable media can be considered to be any storage medium such as solid-state memory, magnetic disks, and optical disks that contain an appropriate set of computer instructions (such as program modules and data structures that enable a processor to perform the techniques described herein). embodied in a tangible form of a computer readable carrier. The computer readable medium may take the form of: an electrical connection having one or more wires; disk storage, magnetic tape cartridge, magnetic tape or other magnetic storage device, portable computer floppy disk, random access memory (RAM), read only memory (ROM) , Erasable Programmable Read-Only Memory (eg, EPROM, EEPROM, or flash memory), or any other tangible medium capable of storing information.

It should be noted that the systems of the present disclosure are shown and described herein as having various modules and units that perform specific functions. It should be understood that these modules and units are only schematically shown based on their functions for an express purpose, and thus these modules and units do not necessarily represent dedicated hardware or software. In this regard, these modules, units and other components may be hardware and/or software implemented to actually perform their specific functions explained herein. The various functions of different components may be combined or separated into hardware and/or software modules in any way, and the separation or combination of these components may be useful. Input/output devices or I/O devices or user interfaces including without limitation keyboards, displays, pointing devices, etc. can be coupled to the system either directly or through intervening I/O controllers. Accordingly, aspects of the disclosure may be embodied in many different forms, and all such forms are intended to be within the scope of the disclosure.

The control system 20 may also include a reservoir pressure sensor 54 and a crank angle sensor. Although sensor 54 is described as a pressure sensor, sensor 54 may be another device calibrated to provide a pressure signal indicative of fuel pressure, such as a load cell, strain gauge, or other device. The crank angle sensor may be a gear sensor 56 , a rotary Hall sensor 58 , or another type of device capable of measuring the angle of rotation of the crankshaft 22 . The control system 20 uses the received signals from the accumulator pressure sensor 54 and the crank angle sensor to determine that the combustion chamber is receiving fuel, and then uses the determined combustion chamber receiving fuel to analyze the signal received from the accumulator pressure sensor 54 .

The control module 50 may be an electronic control unit or electronic control module (ECM) capable of monitoring the condition of the engine 10 or an associated vehicle in which the engine 10 may be located. Control module 50 may be a single processor, a distributed processor, an electronic equivalent of a processor, or any combination of the foregoing as well as software, electronic memory, fixed look-up tables, and the like. The control module 50 may include digital circuits or analog circuits. The control module 50 may be connected to certain components of the engine 10 via a wiring harness 52, but such connection may also be accomplished by other means including wireless systems. For example, control module 50 may be coupled to inlet metering valve 44 and fuel injector 30 and provide control signals to inlet metering valve 44 and fuel injector 30 .

When engine 10 is running, combustion in combustion chamber 32 causes piston 24 to move. Movement of the piston 24 moves a connecting rod 26 drivingly connected to the crankshaft 22 , which movement causes the crankshaft 22 to move rotationally. To aid in timing of combustion events in engine 10 , among other purposes, engine 10 measures the angle of rotation of crankshaft 22 . The angle of rotation of crankshaft 22 may be measured at a number of locations including a primary crankshaft pulley (not shown), an engine flywheel (not shown), an engine camshaft (not shown), or the camshaft itself. The angle of rotation of the crankshaft 22 may be measured with a gear sensor 56 , a rotary Hall sensor 58 , and by other techniques. A signal representing the angle of rotation of the crankshaft 22 (also referred to as the crank angle) is communicated to the control system 20 from a gear sensor 56 , a rotational Hall sensor 58 , or other device.

Crankshaft 22 drives high pressure fuel pump 38 and low pressure fuel pump 48 . Action of the low pressure fuel pump 48 pushes fuel from the fuel tank 36 and moves the fuel along the fuel circuit 34 toward the inlet metering valve 44 . Fuel flows downstream from inlet metering valve 44 along fuel circuit 34 through an inlet check valve (not shown) to high pressure fuel pump 38 . A high pressure fuel pump 38 moves fuel downstream along the fuel circuit 34 through an outlet check valve 46 toward a fuel reservoir or rail 40 . Inlet metering valve 44 receives a signal from control system 20 and is operable to prevent fuel flow to high pressure fuel pump 38 . Inlet metering valve 44 may be a proportional valve, or may be an on-off valve that can be rapidly modulated between an open position and a closed position to regulate the amount of fuel flowing through the valve.

The fuel pressure sensor 54 is connected to the fuel storage 40 so as to be able to detect or measure the fuel pressure in the fuel storage 40 . Fuel pressure sensor 54 sends a signal to controller 50 indicative of fuel pressure in fuel reservoir 40 . A fuel reservoir 40 is connected to each fuel injector 30 . The control system 20 provides control signals to the fuel injectors 30 that determine, for each fuel injector 30 , such as how long the fuel injector 30 is on (operating time) and the number of fueling pulses per cycle of a combustion or injection event. class of operating parameters, which determine the amount of fuel delivered by each fuel injector 30 .

Turning to FIG. 2 , a portion of engine 10 is shown. The control system 20 includes a fuel injector pulse generation module 60 . Pulse generation module 60 receives various inputs and utilizes those inputs to generate fuel injector pulses or signals that are passed to driver 62, which is a part of engine 10, in which the fuel injector pulses are amplified to enable actuation of the fuel injectors. 30 actuators. Such amplification can be voltage, current, or both. An amplified fuel injector pulse is then provided to fuel injector 30 to command fuel injector 30 to open to provide fuel to combustion chamber 32 .

The fuel injector pulse generation module 60 includes an injector on-time module 64 that utilizes various inputs to generate a pulse width or on-time for a fuel injection event, the pulse width or on-time being defined as a period or interval such that The period or interval extends from the moment the nozzle or needle valve element (not shown) moves away from one or more injector holes (not shown) to allow fuel to flow from the fuel injector into the combustion chamber 32 to the nozzle or needle valve The moment the element moves to close the flow of fuel through the injector hole. The fuel injector pulse generation module 60 receives an execution clock signal 66 that is used to time events in the fuel injector pulse generation module 60 . The fuel injector pulse generating module 60 also receives: a fuel pump command signal F _Cmd ; a fuel system pressure signal P, which may be provided by the reservoir pressure sensor 54 ; a pressure setpoint signal P _Sp , which is The signal represents the target pressure in the fuel rail or reservoir 40; and the start of injection command SOI _Cmd which initiates the fuel injection event or the moment of opening of the nozzle or needle valve element, which can also be described as the fuel injector 30 The moment to start opening. Each of these signals may be provided by other modules in the control system 20 , but the fuel system pressure signal may be provided directly by the reservoir pressure sensor 54 . Although the reservoir pressure sensor 54 is shown as being located on the fuel reservoir or rail 40 , it may be located at any high pressure point in the fuel circuit 34 and anywhere between the high pressure fuel pump 38 and the fuel injector 30 . The pressure sensor receives a fuel system pressure signal from the fuel circuit including the high pressure side of the high pressure fuel pump 38 to the high pressure point in the fuel injector 30 .

Each of the signals F _Cmd , P, P _Sp , and SOI _Cmd are received by the injector on-time module 64 . These signals are used by the injector on time module 64 to calculate or determine fuel injector on time. The injector on-time module 64 includes a pressure prediction model module 68 , an injector model module 70 , a summation module 72 , an integration module 74 , and a comparison module 76 . The integration module 74 utilizes F _Cmd to define the initial fuel injector on-time T _On , and the initial fuel injector on-time T _On is provided as input to the pressure prediction model module 68 along with the signals F _Cmd , P, P _Sp and SOI _Cmd , An estimated pressure vector _Pe is determined from a pressure prediction model located in block 68 . The estimated pressure vector P _e is input into the injector model module 70 along with the associated time vector t _e , which utilizes the predicted fuel consumption from t _e (i) to t _e (i-1) seconds at P _e The delta fuel quantity dF injected by the injector produces a vector where _i =1 to the length of te. The Δ fuel amount dF can be expressed in the form of equation (1).

dF=f(P _e , t _e ) Equation (1)

The delta fuel amount dF is provided to summation module 72 .

The summation module 72 adds the input vector or delta fuel amount dF to the interval representing T _On to calculate the estimated amount of fuel F _Est that will be delivered _taking into account T _On . The estimated amount of fuel F _Est is provided to a comparison module 76 where equations (2) and (3) are implemented, where tol is a predetermined tolerance level defining an acceptable deviation between F _Est and F _Cmd , so as to determine whether the calculated value of T _On is acceptable.

F _Est -F _Cmd >tol Equation (2)

F _Est -F _Cmd <-tol Equation (3)

The result of the comparison performed in equation (2) and equation (3) is sent to the integration module 74 . In the integration block 74, T _On is decreased if the condition of equation (2) is satisfied. If the condition of equation (3) is satisfied, T _On is increased. If the value of T _On changes, the processes performed in the pressure prediction model module 68, injector model module 70, summation module 72, and comparison module 76 are performed again until the conditions of equations (2) and (3) are no longer satisfied . If T _On does not satisfy the conditions of Equation (2) and Equation (3), then the value of T _On is considered to have converged to a stable value.

Once the value of T _On converges to a stable value, T _On and SOI _Cmd are received by the TTL pulse generation module 78 which is part of the fuel injector pulse generation module 60 . The TTL pulse generation module 78 generates signals that are communicated to the fuel injectors 30 to control fuel injection events. The fuel injector pulses are then delivered to driver 62 . Driver 62 amplifies the fuel injector pulse and the amplified fuel injector pulse is delivered to fuel injector 30 .

While various embodiments of the present disclosure have been shown and described, it is to be understood that these embodiments are not limited thereto. Those skilled in the art can change, modify and further apply these embodiments. Therefore, these embodiments are not limited to the details previously shown and described, but also include all such changes and modifications.

Claims (15)

1. A fuel assembly for an engine comprising: fuel storage; at least one fuel injector fluidly coupled to the fuel reservoir, the fuel injector configured between an open position allowing fuel flow from the fuel injector and a closed position prohibiting fuel flow from the fuel injector each movement between the open position and the closed position defines a fuel injection cycle, and the fuel injector is configured for a plurality of fuel injection cycles; and a control system having a controller operatively coupled to the fuel injector, the controller configured to receive at least one parameter of the fuel assembly, wherein prior to each of the fuel injection cycles, the The control system is configured to predict the pressure profile of the fuel assembly based on the at least one parameter by determining an estimated pressure of the fuel assembly, calculating a plurality of fuel quantities based on the estimated pressure, calculating an estimated fuel quantity based on the plurality of fuel quantities and comparing the estimated fuel quantity with a predetermined tolerance amount, and adjusting the amount of time the fuel injector remains in the open position during each of the fuel injection cycles in response to the pressure profile . 2. The fuel assembly of claim 1, further comprising a fuel pump, a fuel pump sensor operatively coupled to the fuel pump, and a fuel reservoir sensor operatively coupled to the fuel reservoir, and the The control system is configured to receive signals from the fuel pump sensor and the fuel reservoir sensor to predict the pressure profile of the fuel assembly. 3. The fuel assembly of claim 1, wherein the at least one parameter includes at least one of a fuel pump signal, a fuel assembly pressure signal, a pressure setpoint signal, and a start injection signal. 4. The fuel assembly of claim 1, wherein the control system further comprises: a module configured to determine the estimated pressure of the fuel assembly; and A module configured to calculate the plurality of fuel quantities for the fuel assembly. 5. The fuel assembly of claim 4, wherein the control system includes a device configured to calculate the estimated fuel amount from the plurality of fuel amounts and compare the estimated fuel amount to a predetermined fuel amount module. 6. The fuel assembly of claim 1, wherein the control system includes a module configured to send a signal to the fuel injector and adjust an amount of time the fuel injector remains in the open position. 7. A fuel assembly for an engine, the fuel assembly comprising: at least one fuel injector; and A control system for said fuel assembly, the control system comprising: a controller configured to receive at least one parameter of the fuel assembly; a first module for determining when fuel is flowing from the fuel injector; A second module for predicting a pressure profile of the fuel assembly during injection of fuel, the second module being configured to determine an estimated pressure of the fuel assembly, calculate a plurality of fuel quantities based on the estimated pressure, calculating an estimated fuel amount from the plurality of fuel amounts and comparing the estimated fuel amount to a predetermined tolerance amount; and A third module for adjusting timing of fuel flow from the fuel injector during operation of the engine in response to the predicted pressure profile for the fuel assembly. 8. The fuel assembly of claim 7, further comprising a fuel pump operatively coupled to the fuel injector and a fuel pump sensor operatively coupled to the fuel pump, wherein the first module is configured to receive a signal from the fuel pump sensor. 9. The fuel assembly of claim 7, wherein the fuel injector is configured to move between an open position allowing fuel flow from the fuel injector and a closed position prohibiting fuel flow from the injector, and the control system includes a fourth module configured to receive an adjusted time of fuel flow from the fuel injector and move the fuel injector to the open position. 10. A method of operating a fuel injector in a fuel assembly of an engine, the method comprising: receiving parameters of the fuel assembly during fuel injection; During fuel injection, the pressure distribution of the fuel assembly is predicted based on the parameters of the fuel assembly by determining an estimated pressure of the fuel assembly, calculating a plurality of fuel quantities based on the estimated pressure, calculating a plurality of fuel quantities according to the plurality of calculating an estimated fuel amount for each fuel amount, and comparing the estimated fuel amount with a predetermined tolerance amount; calculating an amount of time for fuel to flow from the fuel injector in response to the predicted pressure profile; and The fuel injector is operated for the amount of time. 11. The method of claim 10, wherein the step of predicting the pressure profile of the fuel assembly occurs after the step of receiving parameters of the fuel assembly. 12. The method of claim 10, further comprising adjusting the amount of time fuel flows from the fuel injector based on the parameter of the fuel assembly. 13. The method of claim 10, wherein receiving a parameter of the fuel assembly includes receiving at least one of a fuel pump signal, a fuel assembly pressure signal, a pressure set point signal, and a start injection signal. 14. The method of claim 10, further comprising: analyzing said estimated fuel quantity against said predetermined tolerance quantity; determining a second estimated pressure of the fuel assembly when the estimated fuel quantity is outside the predetermined tolerance amount; calculating a plurality of second fuel quantities based on the second estimated pressure; calculating a second estimated fuel quantity based on the plurality of second fuel quantities; comparing the second estimated amount of fuel to the predetermined tolerance amount; and A signal for fuel flow is sent to the fuel injector when the second estimated fuel amount corresponds to the predetermined tolerance amount. 15. The method of claim 10, further comprising: initiating a first fuel injection cycle of the fuel injector; adjusting an amount of time fuel flows from the fuel injector after the first fuel injection period; and A second fuel injection cycle of the fuel injector is initiated after an adjusted amount of time fuel flows from the fuel injector.