CN106414985A

CN106414985A - Internal combustion engine and method of direct fuel injection

Info

Publication number: CN106414985A
Application number: CN201380080799.3A
Authority: CN
Inventors: W.布尔默; M.J.弗里克; L.勒曼
Original assignee: Ai Kemote Co
Current assignee: Ai Kemote Co
Priority date: 2013-11-07
Filing date: 2013-11-07
Publication date: 2017-02-15
Also published as: JP2016539272A; EP3066331A1; EP3066331A4; WO2015069265A1

Abstract

A direct fuel injection method and an internal combustion engine provided with appropriate sensors and data input lines to an Engine Control Unit (ECU) for performing this method. The method includes inputting at least data inputs representing a piston position, a rotational speed of the internal combustion engine, and a torque demand into an ECU, calculating in the ECU a calculated start of injection (SOI) for the direct fuel injection that is next based on the data inputs, calculating based on the data inputs and the calculated SOI a desired fuel temperature prior to the direct fuel injection that is next, heating fuel with a system delay not to exceed 5 seconds to the desired heated fuel temperature prior to a direct fuel injection, injecting the heated fuel, and repeating the aforementioned method steps for subsequent direct fuel injections.

Description

Internal combustion engine and the method for direct fuel injection

Technical field

The invention mainly relates to internal combustion engine, and relate more specifically to Combustion System and the fuel efficiency improved and the discharge performance of the internal combustion engine by controlling fuel temperature before ejecting.

Background technology

How completely to depend primarily on burning from the Particulate Emission of internal combustion engine has, because imperfect combustion especially leads to solid carbon particulate.The completeness of burning further relates to fuel efficiency and the minimum of hazardous gas discharge.The complete parameter of impact burning may include engine geometry (B/S), compression ratio, charge motion adjust (trip whirlpool and drum turn), combustion-chamber geometry, the The fuel stream of air guiding, the The fuel stream of wall guided, the stream of fuel guiding, time for spraying, injection pressure, repeatedly project injection, injector nozzle geometry etc..How uniform multiple these parameters impact fuel be mixed with before ignition in a combustion chamber with air.Despite multiple Available Variables, but the final design of combustion system frequently results in performance impairment.This can limit possible fuel efficiency, exhaust emissions, combustion noise and other factorses.

Solid particle discharge from internal combustion engine is identified as possible health risk.Diesel engine is equipped with particulate filter to reduce these discharges.Those of petrol engine, the especially direct-injection (DI) of enforcement gasoline, are limited by the regulation limiting the granule amount that every operating range can discharge now.In order to meet the requirement of regulation in the case of not using particulate filter as possible, auto-maker is studying advanced fuel injection conception, and advanced combustion system.

Particulate Emission is caused by the incomplete mixing of the indoor fuel of the burning of electromotor and air filling.On DI electromotor, the fuel conveying complete quality in finite time window is needed to mean to be usually present very intensive fuel particle group near the top of fuel injector.These granules and then must gasify or from liquid, state is changed into gas, and then fuel vapo(u)r must uniformly be mixed with air in a combustion chamber.The many methods improving this mixing are for example had adverse effect to the efficiency of electromotor by increasing air movement.The method such as drum filling air that energy is given entrance turns or swims the effect that whirlpool has the air total amount that minimizing sucks during induction stroke.

DI petrol engine now uses multiple fuel jets and high-caliber air movement, to be intended to improve the mixing of air and fuel.Engine manufacturer studies the means fuel (＞ 200bar) of very high pressure being used as the particle size reducing in fuel jet now.These granules are less, then the surface area with regard to the volume of granule is bigger.The surface area of this increase allows granule to be easier to evaporate.Granule evaporation is faster, then it is more long to be used for time of mixing with air of fuel vapo(u)r, and therefore fuel vapo(u)r is filling being more evenly distributed in air.

Reach certain pressure, the pressure being increased means that granule is advanced further from fuel injector tip.In some cases, they are advanced enough far so that they clash into the surface of combustor, the referred to as effect of " wall and/or piston soak ".When fuel droplets clash into locular wall, it unlikely evaporates, because wall is generally colder.This fuel will not active combustion, and as through partially combusted hydrocarbon discharge, lead to smoke particle.

Reach 500bar and the means of the even size as the fuel particle reducing in jet for the fuel pressure of 1000bar propose.Enough energy are given fuel so that it almost gasifies immediately when leaving fuel injector by the pressure increasing, and process is referred to as " flash distillation ".This flash distillation has the effect generating the vapor slugs that can mix with filling air quickly.It also limits the distance that fuel is advanced from injector tip, so that the probability that wall gets wet is minimized.However, by gasoline be compressed to these energy very needed for high pressure more significant thereby increases and it is possible to need to be up to about the power of 15-20kW or even more high.Because for providing the high torque (HT) needed for this power, it must pass through alternating current generator directly from electromotor or in the case of electric drive pump.In either case, demand fuel being compressed to this much higher fuel pressure reduces the efficiency of electromotor due to the supplementary loss increasing.

In terms of structure design viewpoint, the pump that can convey with regard to the high-power such high fuel pressure needed for pump is provided both to challenge for pump design with to IC Engine Design.In terms of pump viewpoint, gasoline has the ability of limited lubrication moving parts.Accordingly, it would be desirable to gasoline is reliably increased to these pressure by the special material of petrolift or somewhat complex design, because the moveable part in pump also is subjected to higher power due to high power.In terms of internal combustion engine viewpoint, the petrolift needing such high power and being directly driven by combustion engine is generally connected directly on bent axle by chain or band, this makes the whole design of internal combustion engine complicate, because bent axle is generally difficult to close to connecting any auxiliary body such as petrolift in internal combustion engine.Alternative is to be connected to pump to be usually easier on close camshaft, but this may require that more rigid camshaft design to maintain this high torque (HT) needed for pump that can convey power demand.Because camshaft is mainly designed for actuating valve (it only needs the torque of appropriateness), therefore camshaft generally has ratio and will be used in the much smaller diameter conveying needed for desired pump running torque.Therefore, either type, no matter pump is to be directly driven or directly driven by camshaft by bent axle, and it is made the design of internal combustion engine complicate for various reasons.

It is to determine one of parameter of position of fuel group by fuel injection temperature known to U.S. Patent Application Publication under publication number US 2013/0081592 A1.U.S. Patent Application Publication No. 2013/0081592 A1 proposes to control the position of fuel group via the fuel temperature in layering filling combustion process, and both are used for spark ignition (SI) and compression ignition (CI).Although the prior art generally recognizes that fuel temperature has some impacts to combustion process, that is, pass through to affect the position of fuel group, it fails to instruct any dynamic control of fuel temperature." dynamic " herein the meaning is that it may depend on engine operation state to change.Temperature is affected by fixing point in the prior art application, does not depend dynamically upon real engine mode of operation, e.g., in real time or with become any relation in real time.

Content of the invention

It is an object of the invention to improving efficiency of combustion and therefore reducing particulate emission, but keep fuel pressure to be in suitable level before ejecting simultaneously.

This purpose of the present invention and other purpose are passed through a kind of direct fuel spurt method in the cylinder of internal combustion engine according to the first aspect of the invention and are realized, and the method includes：

A) at least would indicate that the data input of piston position, the rotating speed of internal combustion engine and torque-demand is input in control unit of engine (ECU)；

B) calculated based on data input in control unit of engine (ECU) and start (SOI) for the calculated injection of ensuing direct fuel injection；

C) (SOI) is started based on data input and the injection calculating and calculate the expectation fuel temperature before the injection of ensuing direct fuel；

D) with the system delay less than 5 seconds, fuel is heated to the temperature of desired heated fuel before direct fuel injection；

E) it is injected in the fuel of heating in step d)；

F) repeat step a) is to e) coming for subsequent direct fuel injection.

Above and other objects of the present invention are realized by the following internal combustion engine of inclusion according to the second aspect of the invention：

At least one has the cylinder-piston combination executing linearly moving piston in cylinder, and cylinder-piston combination limits the cylinder volume being connected on fuel injector；

Bent axle；

Heat the fuel heater of fuel in ejector；

Connect the piston to the connecting rod on bent axle；

The sensor of performance piston position；

The sensor of the rotating speed of performance bent axle；

Sense the fuel injector temperature sensor of the temperature of fuel to be sprayed；

Torque-demand sensor；And

Control unit of engine (ECU), it at least includes for the data-in port from the sensor showing piston position, the data wire of the rotating speed, the sensor of fuel injector temperature and torque-demand sensor that show bent axle, and there is the data-out port that at least one is connected to the data wire of fuel heater, wherein, ECU calculates the data output via DOL Data Output Line at least based on the data input from data-in port.

Method and apparatus according to the invention controls fuel temperature, to realize possible maximum homogenizing, therefore reduces the number of the smoke particle of generation.Present invention recognizes that more complete burning can raise preferably to realize by temperature.Additionally, at the design of electromotor and aspects both consuming, fuel heating is than the easily realization of increase fuel pressure.Present invention recognizes that gasifying for more preferable, depending on power operation various variable dynamic controlling fuel temperature can be beneficial.For example, these variables are：I) injection calculating as depended on data input in ECU starts (SOI), ii) torque-demand, iii) rotating speed (can record at the various rotating member parts in motor), and iv) compression ratio (CR), and v) piston position, it can be determined by the position of rotation of bent axle or camshaft.For this purpose, can be using the sensor of the anglec of rotation of any rotating part in the directly sensor of measurement piston position or measurement motor, as, the crank sensor of the anglec of rotation of measurement bent axle, or in alternative, any other rotating part such as camshaft or any actuating device or clutch part, as long as the gear ratio of this rotating part is known and it is not with respect to any sliding of bent axle.

Although compression ratio is constant in many electromotors, newer development program provides change compression ratio, thus this also can consider as variable according to preferred embodiment.

The alternative of higher fuel pressure is to improve fuel temperature.In this case, the energy needed for the temperature of fuel provides vaporising fuel.If the fuel temperature of injection is warm enough, fuel can leave ejector with supercriticality (that is, fine and close steam).Depending on the indoor state of burning during injection, this fuel is positively retained at vapor state, or the very undersized granule of condensable one-tenth, typically smaller than 7 micron diameters.In either case, with mixing in room for the air because the Quick-gasifying of fuel is strengthened.When it is in induction stroke, if the pressure in combustor is relatively low, flash distillation also can occur.Gasification and the mechanism mixing with filling air are identical with the mechanism of the injection of very high pressure, but can be using traditional fuel pressure (about 150bar).The energy adding fuel is in the form of heat.This heat by the used heat supply in exhaust stream, or can electrically can be supplied, or can be supplied by a combination of both.When using electric heating, there is loss in efficiency due to alternator load, but these losses are pumped to, less than with by fuel, those that high pressure phase associates.

The present invention describes based on engine operation state, the method optimizing air and the mixing of fuel by the control of fuel temperature.Main input for this control is piston position and engine loading and speed, and has the compression ratio in the electromotor of variable compression ratio.Engine loading for example can be input to the torque-demand of ECU by it via gas pedal position and rotating speed determines.Gas pedal position is the primary index of the mode of operation for determining electromotor.Although the preferred embodiments of the present invention have envisioned the electromotor of gasoline spark ignition, the present invention same works fine in compression ignition engine.

The particulate emission carrying out on spark ignition engine and the measurement of fuel consumption illustrate the optimum temperature that there is spray fuel, and it is based on engine speed with quantity of power change of generating.Although fuel temperature is unique to the relation of engine speed and load for each electromotor, this relation can be easily determined as a part for engine calibration process.Can be stored in control unit of engine (ECU) as form in the value of the optimum temperature at each point, or as equation, its medium velocity and load are as independent variable.

In DI electromotor, deposit the optimum of spray fuel in the circulating cycle.This most preferably controls determination by mixing rate, Ulva Pertusa strategy and fuel infiltration.Can be used for the time change in the moment change that injection starts mixing.When fuel relatively early injection in the intake stroke, for example, the suitable minimizing of Particulate Emission can be realized with the less heat input to fuel compared to when fuel sprays in compression stroke.In fact, the temperature of fuel occurs injection to raise when starting afterwards in air inlet or compression stroke.Temperature reduces when compression ratio increases, so as to prevent from lighting in advance or pinking generation.Therefore, in test engine, the expectation fuel temperature before injection can be described as with minor function：

T_f=f (SOI, BMEP, rpm, CR),

Wherein T_fFor fuel temperature, SOI is the startup of injection, BMEP is brake mean effective pressure or engine loading, rpm is engine speed, and CR is real engine compression ratio, it is variable in the case of the electromotor of adjustable compression ratio, but is constant in the case of the electromotor with nonadjustable compression ratio.

It should be appreciated that the startup SOI of not direct measurement injection, but depend on various inputs in ECU to calculate, for example, the input of piston position, because it can be determined by the Angle Position of bent axle or camshaft.Sensor due to determining bent axle or camshaft location substantially measures the anglec of rotation, therefore it can also be used for measuring the rotating speed rpm of electromotor.

The preferred implementation of the hardware of this system is made up of fuel preheater, and fuel preheater takes fuel to certain minimum temperature, usually the minimum needed for electromotor.This preheater can heat fuel using discharging gas via heat exchanger, or can use resistance electric heater.Fuel injector comprises electric heater, its temperature needed for being used for carrying to current operation point fuel temperature from its minimum.Heater in fuel injector has low thermal mass, so that fuel temperature can follow the change in engine loading exactly.The preferred temperature of the fuel to be sprayed in particular cycle can be realized by very short delay, for example, only delayed 1-3 circulation, and and this delay can calculate (lookahead by fuel injection cycle certainly in advance Calculation) to consider further.Although a circulation under the engine speed of thousand of turns (rpm) generally per minute is only the fraction of a second in advance, but significant performance raising is possible with length (such as reaches 5 seconds a lot of time delay, preferably 1 to 2 seconds) obtaining, and this is easily achieved for the fuel in fuel injector.Depending on the type of vehicle, for example, by distance using provided truck, the even greater than more high delay time of 5 seconds can be beneficial.For example, for generally, in the vehicle (truck during e.g., commercial long-haul uses) of nearly constant engine operation state downward driving a few hours, the time delay more than 5 seconds still can substantially realize the purpose of the present invention.Although heater is generally arranged in fuel injector and therefore has the quality of very little, it is to be appreciated that even little quality causes some little delays so that fuel temperature will not make an immediate response in the signal of transmission to fuel injector heats device.However, the response time being reduced between 1 with 3 circulations in the response accepting the signal lower heater being derived from ECU can be realized using corresponding design effort.

Heater in ejector is controlled by the electric current controlling to heater by ECU.This electric current is determined by above equation.Ejector heter temperature is realized to the temperature sensor feding back through at using ejector of ECU.In an alternative embodiment, this feedback can be realized by the resistance of HEATER FOR MEASURING by heater is itself functioned as temperature sensor.In another embodiment, feedback can occur by using the model in the ECU of ejector, is the input to model by this The fuel stream and heater current and fuel temperature is output.

In a calibration process, generate arteries and veins spectrogram (map), wherein independent variable is preferential.For example, if reaching the limit of detonability of electromotor, independent variable is better than other variables and is used for optimizing temperature.The startup (SOI) that may be injection better than next variable of other variables.Empirically rule, the time sprayed more after, then be used for the fuel temperature realized needed for evaporating completely higher.Supercritical injection is also to select.The rising further exceeding the temperature of supercriticality point does not significantly further improve evaporation.Next two variables of priority rating are torque-demand and rotating speed, and wherein torque-demand specific speed is more important.Arteries and veins spectrogram can be by needing model tuned in a calibration process to replace.Model can send as an envoy to variable to fuel temperature impact be prioritized decision process.Model can be by empirically determined data genaration, and it to be converted into formula by known mathematic(al) manipulation method such as Fourier or Laplace transform.Once being stored in ECU, then the desired fuel temperature for injection can calculate in the input based on this formula and variable as described above.Under the such calculating based on formula or arteries and veins spectrogram, ECU now has to generate the command output for heater wattage output based on the difference between preferred temperature and actual temperature.

Although the present disclosure additionally applies for jet ignition internal combustion engine, the preferred embodiment of this patent is the fuel system for spark ignition (SI) gasoline engine.The heating of fuel is executed under control of the ecu by means of the electric heater in fuel injector.This fuel injector being capable of spray fuel in the supercritical state.

Alternative minimizes the energy expenditure in ejector using fuel preheater.The system of global optimization can carry out pre-heating fuel using useless aerofluxuss.

Preferred embodiment can be by following enforcement：The fuel temperature of the fuel of heating in sensing step d), and would indicate that and to provide the closed loop control of this fuel temperature in the data input control unit of engine (ECU) of fuel temperature.It is also possible to can be to control ejector heater by opened loop control in alternative, because the property of fuel injector itself is not variable but constant, and fuel temperature be the result of the heater power that can be controlled by opened loop control.

Preferred embodiment can be implemented by the piston position of the sensor sensing internal combustion engine by least one of the bent axle being located at internal combustion engine and camshaft and rotating speed.Although bent axle or camshaft angle position and their both rotating speeds can be utilized same sensor sensing, but being also possible to can be using different sensing sources and means at different elements, for example, by combining the rotating speed measured by known gear ratio at the rotate element of actuating device.

Preferred embodiment can be by following enforcement：The data input being based in step a) in control unit of engine (ECU) is that the calculating of the internal combustion engine with variable compression ratio is used for the desired compression ratio that ensuing direct fuel sprays；Expectation fuel temperature before the injection of ensuing direct fuel is calculated based on injection startup (SOI) calculating in data input, step b) and the compression ratio calculating；And step d) is started to f) based on this desired fuel temperature.Ensuing fuel injection is determined by ECU, and ECU can calculate the ideal data of fuel injection cycle immediately.However, system, of course similar to all systems in real world, has the little time delay of the response to control signal.Furthermore, it is not necessary that the real-time adjustment carrying out 100% to fuel temperature to realize the major part of desired effectss.Additionally, according to preferred embodiment, can be calculated in advance, some in time delay can be taken into account by it.

Preferred embodiment can be by following enforcement：By compression guiding mechanism adjustment variable compressive；Sensing actual compression ratio and would indicate that the data input of actual compression ratio to provide the closed loop control of actual compression ratio in control unit of engine (ECU)；Input represents the data of the actual compression ratio in step a) as additional data input；And represent actual compression ratio data additional data input additional consideration under execution step b) to f).To change compression ratio possibly through the length or position (it can determine that how far piston can advance in cylinder) changing various different elements.Furthermore, it is not necessary that closed loop feedback control is used for controlling the variable compressive of fuel temperature before spraying the control and consideration to implement variable compressive.

Preferred embodiment can be by be implemented by following at least one heat fuel in step a)：I) only electricity consumption in fuel injector；Ii) the electrically heated combination discharged in gas preheating and fuel injector of fuel injector upstream；And iii) fuel injector upstream electric preheating and fuel injector in electrically heated combination.For counter structure, below at least one：I) provide the electric heater as unique heater, the fuel in its heating fuel injector；Ii) it is located at the combination of the electric heater of fuel discharged in gas preheater and heating fuel injector of fuel injector upstream；And the combination of the electric heater of fuel being located in the anticipatory electric heater and heating fuel injector of fuel injector upstream.Despite optional, but preheating has the advantages that to make system have more response, because the amount of the fuel injector heats needed for pre- thermal limit.It is using the another advantage discharging gas preheating, such used heat can be utilized, and therefore can reduce the energy expenditure for fuel heating.

Preferred embodiment can be by following enforcement：The fuel of fuel injector upstream was preheated to before direct fuel injection the pre-heating fuel temperature less than heated fuel temperature；Sense actual pre-heating fuel temperature；Enter data in input control unit of engine (ECU) to represent actual pre-heating fuel temperature；And controlled fuel preheating to desired pre-heating fuel temperature by control unit of engine (ECU).Depending on the level of response and effectiveness, such control of pre-heating fuel temperature can be implemented by considering the actual operating state of electromotor.Compared to ejector heater, the longer time delay of pre-heating fuel temperature can be accepted.In the case of some, the mode of operation of electromotor only negligibly changes, for example, when being travelled on level road with constant speed under cruise control state.In such a state, for example, it is possible to only implement preferable fuel temperature by preheater, thus ejector heater can static with these constant engine operation state continue equally long.In such a state, it may also be advantageous to, the energy expenditure for fuel heating can be provided by the used heat from gas extraction system completely.

Preferred embodiment can be by implementing the fuel preheating of fuel injector upstream to constant pre-heating fuel temperature, and constant pre-heating fuel temperature is less than the heated fuel temperature before direct fuel injection.Although controlling preheating temperature to be preferred for previous reasons, the solution of economy can be by realizing fuel preheating to steady temperature.Preferably, this temperature is less than the expectation fuel temperature before injection, to be provided as reaching the remaining heat of this desired fuel temperature by ejector heater.Alternately, also can accept to be preheated to the temperature higher than desired fuel injection temperature in some limit.Although fuel is cooled to expectation fuel injection temperature in theory possibly as another alternative from preheating temperature, heating is more feasible than cooling.Cooling can electrically be realized, but the air stream also by surrounding air is realized, and it generally has the temperature less than pre-heating fuel temperature.

Preferred embodiment at least one in the mathematical model based on the arteries and veins spectrogram in ECU and physical system can be passed through to execute method and step c) and implement.For corresponding structure, according to preferred embodiment, ECU stores the mathematical model of the physical system of internal combustion engine, mathematical model calculates the data output being sent in DOL Data Output Line via data-out port, or in alternative, ECU stores arteries and veins spectrogram, and arteries and veins spectrogram calculates the data output being sent in DOL Data Output Line via data-out port.This allows substantially to consider unlimited number of variable and mode of operation and substantially consider operational state data and these are stored in arteries and veins spectrogram by rule of thumb measuring the impact of various variables.In order to easily implement the suitable calculating in ECU, it is also possible to by these empirically determined data genaration formula, for example, by Fourier transformation or Laplace transform, or by arbitrary alternate manner of formula is generated based on the discretely or continuously measurand function described to the impact of result.

According to preferred embodiment, the sensor of the sensor and sensing speed of crankshaft that represent piston position is attached in a sensor, the anglec of rotation of at least one of the bent axle of its sensing internal combustion engine and camshaft.Although being more difficult to realize, it is also possible to directly measuring piston position.

According to preferred embodiment, internal combustion engine is additionally provided with the mechanism for changing compression ratio, and control unit of engine (ECU) includes another data-in port, and it is connected on the data wire of the sensor of self-inductance measurement actual compression ratio.The variable of compression ratio is calculated by ECU it means that some modes of operation for electromotor are it is desirable to the specific compression ratio that calculated by ECU, and and then correspondingly adjusts compression ratio.Therefore, measurement compression ratio not required that they be so, but the preferred feature improving accuracy and closed loop feedback control being provided.

Brief description

Describe the present invention according to one or more various embodiments with reference to the following drawings in detail.Accompanying drawing provides merely for illustrative purpose, and depict only typical case or the exemplary embodiment of the present invention.These accompanying drawings provide to be used to promote reader's the understanding of the present invention, and should not be considered as limiting width, scope or the suitability of the present invention.It should be noted that clear and easy in order to illustrate, these accompanying drawings are not necessarily drawn to scale.

Fig. 1 shows example vehicle, can use embodiments of the invention wherein.

Fig. 2 is shown in which to use the example of embodiments of the invention.

Fig. 3 is shown in which to implement the exemplary environments of pumping system according to one embodiment of the invention.

Fig. 4 shows the exemplary pump system according to one embodiment of the invention.

Fig. 5 is shown in which to implement the environment of embodiments of the invention.

Fig. 6 is to show the block diagram generating fuel vapo(u)r and the mixture of air in the cylinder.

Fig. 7 shows the preferred embodiment of the ECU of combustion engine and the various inputs including ECU and output.

Fig. 8 shows the chart illustrating the numbers of particles of transmitting with regard to the dependency between fuel temperature.

List of numerals

1 vehicle

2 fuel supply sources

3 electromotors

4 burning lines

5 cylinders

6 pistons

7 fuel injectors

8 bent axles

9 fuel

10 engine systems

11 fuel filters

12 petrolifts

13 pressure regulators

14 computers

15 fuel injectors

16 fuel system

17 control unit of engine

18 common fuel tracks

19 pumping systems

20 tachometers

21 pressure transducers

22 distribution sensors

23 assignment channels

24 outlets

25 cam sensors

26 crank sensors

27 volume injecting steps

28 microdroplet forming step

29 gasification step

30 fuel vapour blend steps

31 pedal sensors

32 preheaters

33 ejector heaters

34 preheater data wires

35 preheater temperature sensors

36 injector temperature sensor

37 connecting rods

38 pre-heater inlet

39 preheater outlets

40 fuel injectors

41 common fuel rail pressure sensor

42 accelerator pedals

43 injected fuel sprays

44 compression ratio sensors

45 fuel injector heats device data wires.

Specific embodiment

Before describing the present invention in detail, it is useful for describing several exemplary environments (can implement the present invention wherein).One such example is by the vehicle of internal combustion engine energy supply.Fig. 1 shows such vehicle 1.Fuel supply source 2 is arranged in vehicle, and is connected on electromotor 3 by burning line 4.Being used for running engine 3 from the fuel of fuel supply source 2 provides motive power to vehicle 1.

More specifically example is the internal combustion engine as shown in regard to Fig. 2.Electromotor 3 includes multiple cylinders 5 with the piston 6 being arranged therein.Multiple fuel injectors 7 are configured to supply fuel to electromotor 3, and are connected in fuels sources 2 by burning line 4.Piston 6 and cylinder 5 define and for fuel 9 to be metered into cylinder volume therein from fuel injector 7.When fuel 9 is mixed with air and lights, remove piston 6, thus tuning bent axle 8 and providing power.

Fig. 3 shows engine system 10, and it includes electromotor 3, fuel tank 2, fuel filter 11, pump 12, pressure regulator or accumulator 13, computer 14 and fuel injector 15.These components not including electromotor 3 include fuel system 16.Computer 14 may include control unit of engine (ECU) 17, and it receives the input for torque-demand sensor, e.g., from the throttling input of the gas pedal sensor 31 of also referred to as accelerator pedal sensor.Suitable fuel pressure and transfer volume requirements are exported the motor of pump 12 by ECU.Ejector is actuated request output to multiple fuel injectors of electromotor by ECU simultaneously.

Pump 12 absorbs fuel from fuel tank 2, and fuel is pushed to pressure regulator 13, and it controls the fuel pressure in the fuel injector 15 entering electromotor 3.Pressure regulator 13 helps to maintain the certain pressure level in the input of each fuel injector 15.Pressure regulator 13 can be used for when desired by computer 14 control unit of engine from system release pressure.One such example can be when vehicle stops and dallies and needs lower pressure.

Fuel filter 11 is typically mounted between pump 12 and pressure regulator 13.Fuel filter 11 is responsible for filtering the microgranule in the fuel that may be present in fuel tank 2 and impurity.In like fashion, electromotor 3 is from the microgranule that electromotor 3 can be damaged.

Fuel system 16 can implement, e.g., petrol engine and Diesel engine on various types of electromotors, and it may be designed as spark ignition engine (SI) or compression ignition engine (CI).As shown in Figure 3, the fuel injector 15 of electromotor 3 is electronically controlled fuel injector.In the embodiment shown, each fuel injector 15 is electric solenoid valve fuel injector.In one embodiment, pump 12 supplies heated fuel to fuel injector 15, to improve power and the efficiency of electromotor 3.In order to open electromagnetic valve and allow fuel to enter electromotor 3, electric current is sent the magnetic anchor to fuel injector 15 by computer 14.Once armature charges, then form electric field and attract solenoid, to produce the path in the combustor entering electromotor 3.The moment of current discharge is adjusted by computer 14.This can be completed using the feedback of the sensor in electromotor 3.One example of such sensor is the crankshaft position sensor 26 of electromotor as shown in figures 5 and 7.By determining the position of engine crankshaft, computer 14 can calculate the position of piston and determine the moment of current discharge.

In fuel system 16, pump 12 keeps the fuel pressure in common-rail 18 together with pressure regulator 13, and this feeds fuel to each fuel injector 15.As discussed, the solenoid of fuel injector 15 is opened when whenever current discharge.The piston based on electromotor 3 for the moment of current discharge or the position of bent axle.Therefore, in order to keep the less constant pressure in common-rail 18 when electromotor 3 is with high speed operation, the revolution of operation swing offset or petrolift 12 also must increase the pressure to compensate fuel due to being discharged in each fuel injector 15 and pressure and to lose.In other embodiments, such fuel pressure and engine rotation displacement relation can keep in systems, and this system substitutes electronic fuel injection using machine fuel ejector.

Having under the background of the vehicle of the internal combustion engine of and description shown with reference to Fig. 1 to 3, present invention is generally directed to for depending at least parameter of engine loading, the rotating speed of electromotor with spray the combination of the starting time system and method to control fuel temperature.For the internal combustion engine with variable compression ratio, actual compression ratio is also the parameter that will consider.

Fig. 4 schematically shows internal combustion engine, particularly fuel system, some heaters and preheater and various sensor.Pumping system 19 includes fuel tank 2, fuel filter 11, petrolift 12, tachometer 20, pressure regulator or accumulator 13, pressure transducer 21, distribution sensor 22, assignment channel 23, and has the computer 14 of electronic control unit 17.On high level, petrolift 12 absorbs the fuel through fuel filter 11, and fuel is supplied to electromotor (or needing other devices of pressure fluid) via assignment channel 23.In one embodiment, assignment channel 23 is common-rail 18, and it is configured to supply fuel to multiple fuel injectors 15.Also common-rail 18 can be replaced using other types of assignment channel 23.

In pumping system 19, pump 12 can be positive-dispacement pump.Pump 12 is preferably radial piston pump, and it has high efficiency together with the most as little as not having fluid to leak out piston pumping chamber.The motor being attached on pump 12 makes axle rotate, and axle makes pump operate.Each rotation of motor reel is corresponding to the set volume of the fluid being pumped by pump piston.

Tachometer 20 may be configured to the swing offset of motor sensor axle, because it is related to the volume of the fluid of pumping, and by swing offset data is activation to computer 14.Tachometer 20 can be Hall element, and it has 1-3 pole depending on user's request.

Pressure transducer 21 may be configured to monitor the pressure of the fluid at the outlet 24 of pump 12, and pressure data is sent to computer 14., at outlet 24, there is corresponding fluid pressure value in each the swing offset value for the motor of pump 12 or rotational speed counting.Computer 14 by under pressure and motor swing offset data record and tabular, to produce the motor swing offset of pump 12 curve chart to pressure.Swing offset and pressure data can usage record device be collected to be used for storing the data in memorizer, and/or send data to teledata stocking system.Pressure data can be analog or digital data.

Preheater 32 is arranged in assignment channel 23.Other other positions for arranging preheater are also possible, for example, in the common-rail 18 supplying fuel to fuel injector.The temperature of preheating is typically set at the value less than fuel injector heats device 33.It is usually provided with multiple fuel injector heats devices, each ejector is all to should have one.However, it is also possible to can be setting one public ejector heater, the fuel in its heated injectors.Temperature in preheater by ECU control or can be positively retained under steady temperature.One reason of setting preheater is to make system have more response, i.e. by reducing the heating amount needing to be provided by ejector heater 33.In order to control preheater 32, preheater data wire 34 can be set to preheater 32 is connected on ECU 17, or is only generally connected on computer CPU 14.Preheater temperature sensor 35 may be provided at common-rail or other positions, for example, assignment channel 23.Injector temperature sensor 36 may be provided at ejector or interior, or close to for fuel to be sprayed outlet port.Setting fuel injector heats device data wire 45 is to receive the control signal from CPU or ECU, to control fuel heating.

Fig. 5 schematically shows the data input data output of ECU.For example, electromotor 3 may include the internal combustion engine of gasoline direct injection engine, Diesel engine or any other spray fuel.Sensor such as cam sensor 25 or crank sensor 26 or both power operation data is provided to control unit of engine (ECU) 17.Cam sensor 25 is that ambiguity is minimum for determining next fuel recycle, and crank sensor is that ambiguity is minimum for the piston position determining given any time point.Additional input is derived from injector temperature sensor 36 and preheater temperature sensor 35, and the torque demand signal from gas pedal sensor 31.For simplicity, do not show that all outputs, for example, export preheater 32 and ejector heater 33 as being shown as fuel injector heats device data wire 45 and preheater data wire 34 in the diagram.

ECU 17 determine using this data electromotor operates at present on which operation planar.As described herein, using the predetermined ejector pin profile of this information and leap power operation plane, ECU determines the ejector pin profile of the fuel injector of electromotor 3 at operating point.Fuel injector 15 is for example connected with ECU 17 via fuel injector driver and causes the ejector pin profile being determined according to current operation point to inject fuel in electromotor 3.

Fig. 6 show fuel injection, microdroplet formed, the process of gasification and mixed vapour in the cylinder.A certain amount of fuel at step 27 with spray injection in combustion volume.Then, injected fuel spray is configured to microdroplet at step 28.Then fuel droplets gasify at step 29, and fuel vapo(u)r is mixed with the air being present in combustion volume (being the cylinder of internal combustion engine 3 here) at step 30.Fuel is finally lighted under the heat of compression and possibly under the injection of igniting charge, or to be lighted by spark.

Fig. 7 schematically shows internal combustion engine 3, and it includes driving the bent axle 8 of multiple pistons 6 via connecting rod 37.Compression ratio can be determined by compression ratio sensor 44 and feed back in ECU 17.The rotating speed of bent axle is measured by crank sensor 26, and crank sensor 26 is designed as the sensor combining according to this embodiment, and it measures the rotating speed of the spin angular position of bent axle and bent axle simultaneously.Bent axle 8 also drives high pressure fuel pump 12.Pump 12 obtains low-pressure fuel 9 from fuel supply source 2 such as fuel tank, and compresses it to the required high pressure of operation.This fuel under high pressure is delivered to fuel preheater 32 via assignment channel 23 such as connecting tube.In this embodiment, fuel preheater 32 heats fuel using carrying out self-purging used heat.Discharge gas from exhaust manifold enters preheater 32 at pre-heater inlet 38, transfers heat to pressurized fuel, and and then leaves preheater 32 at preheater outlet 39.Control signal is sent to preheater via preheater data wire 34 by the heating power of preheater by ECU control, ECU.Heated fuel is delivered to common fuel track 18 via continuous assignment channel 23 such as second pipe.Common fuel track 18 is used as distributing manifold, to provide fuel into fuel injector 40.The pressure of the fuel in common fuel track 18 is measured by common fuel rail pressure sensor 41.Each fuel injector 40 comprises fuel heater 33, and alternatively fuel temperature sensor 36, and it is connected on ECU by data wire.Under send the control of control unit of engine (ECU) 17 of control signal via fuel injector heats device data wire 45, injected fuel spray 43 is directly supplied in the cylinder of internal combustion engine 3 fuel injector, and depend on time for spraying, especially it is fed in the combustor of internal combustion engine 3.The torque being provided by electromotor is controlled via the input of gas pedal sensor 31 by accelerator pedal 42 based on driver by ECU.

In operation, ECU 17 obtains input from crankshaft speed sensor 26, compression ratio sensor 44, fuel pressure sensor 41, fuel temperature sensor 36 and gas pedal sensor 31.Based on these inputs, ECU7 calculates desired fuel temperature, and via fuel injector heats device data wire 45 output control signal, control signal drives fuel heater 33, so that the fuel in fuel injector is heated to preferred temperature.

As beginning discussed like that it is desirable to fuel temperature be also the injection startup SOI time function.However, this SOI is mode of operation based on electromotor calculating as preferable injection starting time.While it may be possible to sensing this injection starting time and providing ECU as parameter by closed loop feedback control, because ECU controls this SOI, but it also is used as directly being calculated by ECU, and this makes SOI sensor is redundancy.

Fig. 8 represents the characteristic curve to fuel temperature for the amount of the Particulate Emission of generation.Each bar line on figure represents that unique injection starts (SOI) time.Line is before the top dead-centre of compression stroke with number of rotation labelling.Similar curve will be in progress for the unique value of required torque and the unique value of compression ratio (CR).ECU 17 shown in Fig. 1 will determine the correct fuel temperature of each mode of operation being used for electromotor using these characteristic curves.

Claims

1. the direct fuel injection method in a kind of cylinder making fuel enter internal combustion engine, methods described includes：

B) calculated based on described data input in described control unit of engine (ECU) and spray calculated injection startup (SOI) for ensuing described direct fuel；

C) (SOI) is started based on described data input and the injection calculating and calculate the expectation fuel temperature before ensuing described direct fuel injection；

D) with the system delay heating fuel extremely described desired heated fuel temperature less than 5 seconds before direct fuel injection；

E) it is injected in the described fuel of heating in step d)；

F) repeat step a) is to e) for subsequent direct fuel injection.

2. method according to claim 1, it further includes to sense the fuel temperature of the described fuel of heating in step d), and would indicate that in the control unit of engine described in data input (ECU) of described fuel temperature for providing the closed loop control of described fuel temperature.

3. method according to claim 1, it further includes to be sensed piston position and the rotating speed of described internal combustion engine by the sensor of at least one of the bent axle being arranged on described internal combustion engine and camshaft.

4. method according to claim 1, it further includes：The data input being based in step a) in described control unit of engine (ECU) is that the internal combustion engine with variable compression ratio calculates the desired compression ratio spraying for ensuing described direct fuel；Expectation fuel temperature before ensuing direct fuel injection is calculated based on described data input, described injection startup (SOI) calculating in step b) and the compression ratio calculating；And step d) is started to f) based on this desired fuel temperature.

5. method according to claim 4, it further includes：Described variable compression ratio is adjusted by compression ratio adjustment mechanism；Sensing actual compression ratio and would indicate that the data input of described actual compression ratio to control unit of engine (ECU) in for providing described compression ratio and the closed loop control of therefore described actual compression ratio；Input represents that the data of the described actual compression ratio in step a) inputs as additional data；And additionally consider the data representing described actual compression ratio additional data input under execution step b) to f).

6. method according to claim 1, it further includes to heat described fuel in step a) by following at least one：I) only electricity consumption in described fuel injector；Ii) the electrically heated combination discharged in gas preheating and described fuel injector of described fuel injector upstream；And iii) described fuel injector upstream electric preheating and described fuel injector in electrically heated combination.

7. method according to claim 1, it further includes：The fuel of described fuel injector upstream was preheated to before direct fuel injection the pre-heating fuel temperature less than described heated fuel temperature；Sense described actual pre-heating fuel temperature；Enter data into and be input in described control unit of engine (ECU) to represent described actual pre-heating fuel temperature；And controlled fuel preheating to described desired pre-heating fuel temperature by described control unit of engine (ECU).

8. method according to claim 1, it further includes that, by the fuel preheating of described fuel injector upstream to constant pre-heating fuel temperature, described constant pre-heating fuel temperature is less than the heated fuel temperature before direct fuel injection.

9. method according to claim 1, it further includes at least one of mathematical model based on the arteries and veins spectrogram in described ECU and physical system execution method and step c).

10. a kind of internal combustion engine, it includes：

At least one has the cylinder-piston combination executing linearly moving piston in cylinder, and described cylinder-piston combination limits the cylinder volume being connected on fuel injector；

Bent axle；

Heat the fuel heater of fuel in described ejector；

Described piston is connected to the connecting rod on described bent axle；

The sensor of performance piston position；

Show the sensor of the rotating speed of described bent axle；

Torque-demand sensor；

Control unit of engine (ECU), its at least include for from described performance piston position sensor, the data wire of the rotating speed of the described bent axle of described performance, the sensor of described fuel injector temperature and described torque-demand sensor data-in port, and there is the data-out port that at least one is connected to the data wire of described fuel heater, wherein, described ECU calculates the data output via described DOL Data Output Line at least based on the data input from described data-in port.

11. internal combustion engines according to claim 1, wherein, the sensor combinations of the rotating speed of the described performance sensor of piston position and described performance bent axle in a sensor, to sense the anglec of rotation of at least one of bent axle and the camshaft of described internal combustion engine.

12. internal combustion engines according to claim 10, wherein, described internal combustion engine is further provided with the mechanism for changing described compression ratio, and described control unit of engine (ECU) includes another data-in port, it is connected on the data wire of the sensor of actual compression ratio described in self-inductance measurement.

13. internal combustion engines according to claim 10, it further includes following at least one：I) as the electric heater of unique heater, its heating fuel in described fuel injector；Ii) it is located at the discharge gas preheater of described fuel injector upstream and combining of the electric heater of the fuel heating in described fuel injector；And it is located at the anticipatory electric heater of described fuel injector upstream and combining of the electric heater of the fuel heating in described fuel injector.

14. internal combustion engines according to claim 10, wherein, described ECU storage calculates the arteries and veins spectrogram of described data output, and described data output is sent in described DOL Data Output Line via described data-out port.

15. internal combustion engines according to claim 10, wherein, ECU stores the mathematical model of the physical system of described internal combustion engine, and described mathematical model calculates described data output, and described data output is sent in described DOL Data Output Line via described data-out port.